老年人心臟性猝死是指急性癥狀發作后1小時內發生的以意識突然喪失為特征的由心臟原因引起的(de)自然死(si)亡(wang)(wang)(wang)。1979年國(guo)際心(xin)臟病學會(hui)、美國(guo)心(xin)臟學會(hui)以及1970年世界(jie)衛生組織定(ding)義的(de)猝死(si)為:急(ji)性(xing)癥狀發生后(hou)即刻或(huo)(huo)者(zhe)(zhe)情況24小(xiao)時(shi)內發生的(de)意外死(si)亡(wang)(wang)(wang)。目前大(da)多數學者(zhe)(zhe)傾向(xiang)于將猝死(si)的(de)時(shi)間限定(ding)在(zai)發病1小(xiao)時(shi)內。其特點有三,①死(si)亡(wang)(wang)(wang)急(ji)驟,②死(si)亡(wang)(wang)(wang)出人意料,③自然死(si)亡(wang)(wang)(wang)或(huo)(huo)非暴(bao)力死(si)亡(wang)(wang)(wang)。
(1)冠心病
冠心(xin)病(bing)(急性(xing)(xing)(xing)缺(que)血事(shi)件,慢(man)性(xing)(xing)(xing)缺(que)血性(xing)(xing)(xing)心(xin)臟(zang)病(bing))是心(xin)臟(zang)性(xing)(xing)(xing)猝死(si)的(de)最常(chang)見的(de)原因。對心(xin)臟(zang)性(xing)(xing)(xing)猝死(si)的(de)尸檢(jian)發(fa)現,大約80%的(de)患者(zhe)具有不同程(cheng)度的(de)冠狀動脈病(bing)變,大約2/3以上(shang)的(de)患者(zhe)為2支或(huo)3支以上(shang)的(de)病(bing)變。心(xin)肌梗死(si)后伴有左心(xin)功能下降或(huo)嚴重室(shi)性(xing)(xing)(xing)心(xin)律失常(chang)的(de)患者(zhe),心(xin)臟(zang)性(xing)(xing)(xing)猝死(si)的(de)發(fa)生率顯著增加。
(2)心肌病
擴張型心(xin)肌(ji)病(bing)的(de)(de)心(xin)臟性(xing)(xing)(xing)猝死(si)(si)率(lv)為2%,在伴有(you)室(shi)性(xing)(xing)(xing)心(xin)律失常時心(xin)臟性(xing)(xing)(xing)猝死(si)(si)率(lv)可明顯增加。而肥厚(hou)性(xing)(xing)(xing)心(xin)肌(ji)病(bing)患(huan)者(zhe)中心(xin)臟性(xing)(xing)(xing)猝死(si)(si)更常見。大多(duo)(duo)數(shu)學者(zhe)報道,肥厚(hou)性(xing)(xing)(xing)心(xin)肌(ji)病(bing)的(de)(de)年病(bing)死(si)(si)率(lv)為3%~4%,其中大多(duo)(duo)數(shu)為心(xin)臟性(xing)(xing)(xing)猝死(si)(si)。在肥厚(hou)性(xing)(xing)(xing)心(xin)肌(ji)病(bing)患(huan)者(zhe),下列情形(xing)為發生(sheng)心(xin)臟性(xing)(xing)(xing)猝死(si)(si)的(de)(de)高(gao)危因(yin)素:①年齡較輕,在30歲以下。②曾有(you)暈(yun)厥病(bing)史。③既(ji)往有(you)心(xin)臟性(xing)(xing)(xing)猝死(si)(si)的(de)(de)家族史。此外(wai),各種原因(yin)產生(sheng)的(de)(de)心(xin)肌(ji)病(bing)和致(zhi)心(xin)律失常性(xing)(xing)(xing)心(xin)肌(ji)病(bing)也容易發生(sheng)心(xin)臟性(xing)(xing)(xing)猝死(si)(si)。
(3)心臟瓣膜炎癥浸潤
現已公(gong)認,二尖(jian)瓣脫垂(chui)綜合征可發(fa)生心(xin)臟性(xing)猝死,但(dan)發(fa)生率不高。據(ju)Jersaty報道,二尖(jian)瓣脫垂(chui)患者伴(ban)有(you)下列情形者易發(fa)生心(xin)臟性(xing)猝死:①40歲(sui)左右的女性(xing)患者。②有(you)暈厥病史。③心(xin)電圖上有(you)ST段改變或有(you)頻發(fa)室(shi)性(xing)期(qi)前收縮(suo)等(deng)室(shi)性(xing)心(xin)律失(shi)常。④有(you)“喀(ka)啦”音和收縮(suo)晚期(qi)或全收縮(suo)期(qi)雜音。
(4)心律失常
一般不易發生心(xin)(xin)臟(zang)性(xing)猝(cu)死,但在老年(nian)患者,常可并發嚴重(zhong)的冠狀(zhuang)動脈(mo)狹窄或(huo)高(gao)血壓致(zhi)嚴重(zhong)左心(xin)(xin)室(shi)肥厚型心(xin)(xin)肌病(bing)的左心(xin)(xin)室(shi)流(liu)出道梗阻時,快速(su)性(xing)室(shi)上性(xing)心(xin)(xin)律失常發作時也易發生心(xin)(xin)臟(zang)性(xing)猝(cu)死。
多數(shu)學(xue)(xue)者認為,嚴重(zhong)的(de)(de)(de)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)可發(fa)(fa)生(sheng)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si),尤其(qi)(qi)在(zai)患有嚴重(zhong)器質性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)病(bing)(bing)(bing)的(de)(de)(de)老年患者。目前(qian),室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)在(zai)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)中的(de)(de)(de)意(yi)(yi)義尚存爭議(yi)。有些學(xue)(xue)者發(fa)(fa)現(xian),室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)并不能(neng)(neng)增加(jia)(jia)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)發(fa)(fa)生(sheng)率,尤其(qi)(qi)是(shi)(shi)無(wu)(wu)明顯器質性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)病(bing)(bing)(bing)基礎(chu)的(de)(de)(de)單(dan)純性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)。但也有一些研究(jiu)提示,室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)本(ben)身即是(shi)(shi)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)危險(xian)因(yin)(yin)素,特別(bie)是(shi)(shi)嚴重(zhong)的(de)(de)(de)冠狀動(dong)脈病(bing)(bing)(bing)變(bian)或心(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗死(si)(si)(si)(si)(si)(si)后的(de)(de)(de)患者,頻發(fa)(fa)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)對心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)發(fa)(fa)生(sheng)具有一定的(de)(de)(de)意(yi)(yi)義,特別(bie)是(shi)(shi)合(he)并有左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)肥厚、室(shi)(shi)(shi)(shi)內傳導(dao)阻(zu)滯(zhi)和(he)(he)(he)ST-T改變(bian)者。而室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過(guo)速(su)(su)(su)(su)(su)(su)(su)在(zai)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)中的(de)(de)(de)意(yi)(yi)義比室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)為大(da)。在(zai)臨(lin)床(chuang)中,我們常(chang)(chang)(chang)把室(shi)(shi)(shi)(shi)速(su)(su)(su)(su)(su)(su)(su)或成(cheng)對、多源及頻發(fa)(fa)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)稱為復雜(za)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)。Morganroth根據(ju)復雜(za)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)引起(qi)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)危險(xian)程度(du),將(jiang)復雜(za)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)分(fen)為良性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)占30%,其(qi)(qi)左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)功能(neng)(neng)和(he)(he)(he)血(xue)流動(dong)力(li)學(xue)(xue)均正(zheng)常(chang)(chang)(chang),發(fa)(fa)生(sheng)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)危險(xian)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)極(ji)小;潛在(zai)惡性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)占65%,心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)結(jie)構(gou)輕度(du)異常(chang)(chang)(chang),有心(xin)(xin)(xin)(xin)(xin)(xin)功能(neng)(neng)不全(quan)和(he)(he)(he)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)異位激動(dong),如(ru)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收(shou)(shou)縮(suo)(suo)和(he)(he)(he)(或)非(fei)持續(xu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)速(su)(su)(su)(su)(su)(su)(su),無(wu)(wu)血(xue)流動(dong)力(li)學(xue)(xue)障(zhang)礙,但心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)危險(xian)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)增加(jia)(jia);惡性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)占5%,幾乎都有血(xue)流動(dong)力(li)學(xue)(xue)表現(xian)和(he)(he)(he)體征(zheng)(zheng)(暈厥,心(xin)(xin)(xin)(xin)(xin)(xin)功能(neng)(neng)不全(quan),心(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)缺血(xue)或低血(xue)壓)其(qi)(qi)發(fa)(fa)生(sheng)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)危險(xian)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)最(zui)大(da)。臨(lin)床(chuang)上常(chang)(chang)(chang)見5種類型(xing):①心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)率≥230bpm的(de)(de)(de)持續(xu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)單(dan)形性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)速(su)(su)(su)(su)(su)(su)(su)。②心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)率逐漸加(jia)(jia)速(su)(su)(su)(su)(su)(su)(su)的(de)(de)(de)室(shi)(shi)(shi)(shi)速(su)(su)(su)(su)(su)(su)(su)或可蛻變(bian)為室(shi)(shi)(shi)(shi)撲和(he)(he)(he)(或)室(shi)(shi)(shi)(shi)顫趨勢(shi)者。③室(shi)(shi)(shi)(shi)速(su)(su)(su)(su)(su)(su)(su)伴(ban)嚴重(zhong)血(xue)流動(dong)力(li)學(xue)(xue)障(zhang)礙如(ru)暈厥,左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)功能(neng)(neng)不全(quan)和(he)(he)(he)低血(xue)壓。④多形性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(包括長Q-T綜合(he)征(zheng)(zheng)合(he)并的(de)(de)(de)尖端扭(niu)轉型(xing))室(shi)(shi)(shi)(shi)速(su)(su)(su)(su)(su)(su)(su)。⑤室(shi)(shi)(shi)(shi)撲和(he)(he)(he)(或)室(shi)(shi)(shi)(shi)顫起(qi)始心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)即為室(shi)(shi)(shi)(shi)撲和(he)(he)(he)(或)室(shi)(shi)(shi)(shi)顫(如(ru)特發(fa)(fa)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)顫,Brugada綜合(he)征(zheng)(zheng))。臨(lin)床(chuang)表現(xian)為阿-斯綜合(he)征(zheng)(zheng)發(fa)(fa)作。而由心(xin)(xin)(xin)(xin)(xin)(xin)電圖證實的(de)(de)(de)大(da)多數(shu)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)發(fa)(fa)作(65%~85%)是(shi)(shi)由心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)顫動(dong)之(zhi)類的(de)(de)(de)惡性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)所致(zhi)。但緩慢性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)也可能(neng)(neng)是(shi)(shi)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)(si)(si)(si)(si)的(de)(de)(de)潛在(zai)原因(yin)(yin),并可能(neng)(neng)在(zai)記錄到緩慢性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)之(zhi)前(qian)就已轉變(bian)為心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)顫動(dong)。
預激綜(zong)合征(zheng)患者并發房室(shi)折(zhe)返性心(xin)(xin)(xin)動(dong)過速(su)、心(xin)(xin)(xin)房顫動(dong)等快(kuai)速(su)性心(xin)(xin)(xin)律失常(chang)者占40%~80%。但發生(sheng)心(xin)(xin)(xin)臟性猝死的(de)危險性較(jiao)低,有調查在4%以下(xia),老年(nian)患者也未(wei)見心(xin)(xin)(xin)臟性猝死增(zeng)加的(de)報道。
(5)其他
糖(tang)(tang)尿(niao)病(bing)除了增(zeng)加冠心病(bing)的發(fa)生率(lv)(lv)外,本身也可損傷心肌而(er)增(zeng)加心臟性猝死的發(fa)生率(lv)(lv)。尤其女性患者的心臟性猝死發(fa)生率(lv)(lv)增(zeng)加更明顯,較同年齡組而(er)無糖(tang)(tang)尿(niao)病(bing)的患者增(zeng)加3倍。
目(mu)前已知,發(fa)生心(xin)臟性猝(cu)死的機制主要(yao)為(wei)嚴重(zhong)的室(shi)性心(xin)律失常,包括室(shi)性心(xin)動過(guo)速,心(xin)室(shi)顫動等。也(ye)有一部分人為(wei)突然發(fa)生的嚴重(zhong)血流動力學障礙,心(xin)臟破裂等。
一般(ban)認為,心(xin)(xin)室顫動是多發的(de)(de)折返小波(bo)(bo)引起的(de)(de)持續性快而不(bu)規(gui)則的(de)(de)心(xin)(xin)室激動。心(xin)(xin)室顫動的(de)(de)發生必(bi)需包括以下幾個基本條件,即異步和(he)分(fen)離的(de)(de)局部波(bo)(bo)前興奮,傳導延緩和(he)心(xin)(xin)室不(bu)應期縮短。這些變(bian)化,在缺血的(de)(de)心(xin)(xin)肌中均可出現。
(1)缺(que)血性(xing)室(shi)(shi)(shi)(shi)性(xing)心(xin)律(lv)(lv)(lv)(lv)失常(chang)(chang)(chang):包括(kuo)急性(xing)心(xin)肌(ji)(ji)缺(que)血所(suo)致的(de)室(shi)(shi)(shi)(shi)性(xing)心(xin)律(lv)(lv)(lv)(lv)失常(chang)(chang)(chang)和心(xin)肌(ji)(ji)梗死(si)(si)后陳(chen)舊性(xing)病變并發(fa)(fa)的(de)室(shi)(shi)(shi)(shi)性(xing)心(xin)律(lv)(lv)(lv)(lv)失常(chang)(chang)(chang)。如果急性(xing)心(xin)肌(ji)(ji)缺(que)血發(fa)(fa)生(sheng)在心(xin)肌(ji)(ji)梗死(si)(si)后瘢痕愈(yu)合(he)的(de)邊緣心(xin)肌(ji)(ji),則(ze)(ze)室(shi)(shi)(shi)(shi)性(xing)心(xin)律(lv)(lv)(lv)(lv)失常(chang)(chang)(chang)的(de)發(fa)(fa)生(sheng)率更高。在急性(xing)心(xin)肌(ji)(ji)缺(que)血時,局部心(xin)肌(ji)(ji)組(zu)織灌注不足,導(dao)致缺(que)血部位的(de)心(xin)肌(ji)(ji)能量(liang)代謝較正常(chang)(chang)(chang)心(xin)肌(ji)(ji)組(zu)織明顯(xian)降低,大量(liang)游離脂肪酸(suan)(suan)(FFA)堆積,細胞內(nei)乳酸(suan)(suan)含(han)量(liang)增(zeng)(zeng)加(jia),細胞內(nei)鉀、鎂離子(zi)外流,則(ze)(ze)靜息(xi)電位的(de)負值(zhi)進一步增(zeng)(zeng)加(jia),形(xing)成(cheng)舒(shu)張(zhang)期電位。同時,動(dong)作(zuo)電位的(de)振(zhen)幅下降,去極化的(de)速度減(jian)慢(man),興奮傳(chuan)導(dao)速度減(jian)慢(man),則(ze)(ze)心(xin)肌(ji)(ji)自律(lv)(lv)(lv)(lv)性(xing)增(zeng)(zeng)強(qiang),并易于(yu)形(xing)成(cheng)折返的(de)條件而發(fa)(fa)生(sheng)室(shi)(shi)(shi)(shi)性(xing)折返性(xing)心(xin)律(lv)(lv)(lv)(lv)失常(chang)(chang)(chang)及心(xin)室(shi)(shi)(shi)(shi)顫動(dong)。而同時存在左心(xin)功能不全的(de)患(huan)者,心(xin)臟(zang)性(xing)猝(cu)死(si)(si)的(de)發(fa)(fa)生(sheng)率則(ze)(ze)更高,尤其左室(shi)(shi)(shi)(shi)射血分數低于(yu)30%是心(xin)臟(zang)性(xing)猝(cu)死(si)(si)的(de)最強(qiang)的(de)預(yu)測因(yin)素。
現已知再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)是發(fa)(fa)生(sheng)(sheng)(sheng)(sheng)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝死的(de)(de)(de)(de)(de)重要機(ji)(ji)制。再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)可見(jian)于冠(guan)(guan)狀(zhuang)動(dong)(dong)(dong)(dong)(dong)(dong)脈(mo)痙攣緩(huan)解以后,也(ye)可見(jian)于急性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗死溶栓治療或(huo)機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)(xing)粉碎(sui)斑塊后使完全(quan)閉(bi)塞的(de)(de)(de)(de)(de)血(xue)管再(zai)(zai)(zai)(zai)通(tong)等情況。常(chang)在(zai)冠(guan)(guan)狀(zhuang)動(dong)(dong)(dong)(dong)(dong)(dong)脈(mo)再(zai)(zai)(zai)(zai)通(tong)后幾秒鐘而出現再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)。許多研究(jiu)表明(ming),冠(guan)(guan)狀(zhuang)動(dong)(dong)(dong)(dong)(dong)(dong)脈(mo)再(zai)(zai)(zai)(zai)通(tong)時,再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)的(de)(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)(sheng)(sheng)率(lv)高達82%。在(zai)再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)的(de)(de)(de)(de)(de)不同類型中(zhong)60%~80%為加速(su)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)自(zi)主(zhu)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)和(he)(he)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收縮,可引(yin)起(qi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝死的(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)為室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)(dong)過(guo)(guo)(guo)(guo)速(su)和(he)(he)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)顫動(dong)(dong)(dong)(dong)(dong)(dong),嚴重的(de)(de)(de)(de)(de)緩(huan)慢性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)也(ye)可引(yin)起(qi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝死。而再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)的(de)(de)(de)(de)(de)類型和(he)(he)冠(guan)(guan)狀(zhuang)動(dong)(dong)(dong)(dong)(dong)(dong)脈(mo)的(de)(de)(de)(de)(de)再(zai)(zai)(zai)(zai)通(tong)部位(wei)有(you)一(yi)(yi)定的(de)(de)(de)(de)(de)關系。左(zuo)前(qian)降支和(he)(he)左(zuo)旋(xuan)支再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)時易發(fa)(fa)生(sheng)(sheng)(sheng)(sheng)加速(su)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)自(zi)主(zhu)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv),室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)(dong)過(guo)(guo)(guo)(guo)速(su)和(he)(he)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)顫動(dong)(dong)(dong)(dong)(dong)(dong)。右(you)冠(guan)(guan)狀(zhuang)動(dong)(dong)(dong)(dong)(dong)(dong)脈(mo)阻塞再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)時易發(fa)(fa)生(sheng)(sheng)(sheng)(sheng)竇性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)(dong)過(guo)(guo)(guo)(guo)緩(huan),房室(shi)(shi)(shi)傳(chuan)導阻滯(zhi)。實驗研究(jiu)提示,再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)的(de)(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)(sheng)(sheng)機(ji)(ji)制包括觸發(fa)(fa)激(ji)動(dong)(dong)(dong)(dong)(dong)(dong)、折返激(ji)動(dong)(dong)(dong)(dong)(dong)(dong)和(he)(he)異(yi)位(wei)自(zi)律(lv)(lv)(lv)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)增高。目前(qian)多數(shu)學者認為,觸發(fa)(fa)激(ji)動(dong)(dong)(dong)(dong)(dong)(dong)在(zai)再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)的(de)(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)(sheng)(sheng)中(zhong)占(zhan)據重要位(wei)置。而折返機(ji)(ji)制的(de)(de)(de)(de)(de)產生(sheng)(sheng)(sheng)(sheng)可能與再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)后心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌細胞電(dian)生(sheng)(sheng)(sheng)(sheng)理恢復(fu)(fu)不均勻有(you)關。心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌缺(que)(que)血(xue)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)損(sun)傷使心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌細胞的(de)(de)(de)(de)(de)電(dian)生(sheng)(sheng)(sheng)(sheng)理改(gai)變不均勻,血(xue)管再(zai)(zai)(zai)(zai)通(tong)后的(de)(de)(de)(de)(de)再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)使血(xue)流恢復(fu)(fu),但恢復(fu)(fu)血(xue)流后的(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌細胞血(xue)液供應(ying)和(he)(he)代(dai)謝恢復(fu)(fu)也(ye)不均勻,結果導致缺(que)(que)血(xue)區(qu)內心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌應(ying)激(ji)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)的(de)(de)(de)(de)(de)恢復(fu)(fu)程度(du)不一(yi)(yi)致,則(ze)易于形(xing)成折返而引(yin)起(qi)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)(dong)過(guo)(guo)(guo)(guo)速(su)和(he)(he)(或(huo))心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)顫動(dong)(dong)(dong)(dong)(dong)(dong)。此(ci)外,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌缺(que)(que)血(xue)-再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)損(sun)傷也(ye)可引(yin)起(qi)異(yi)位(wei)興(xing)奮灶的(de)(de)(de)(de)(de)自(zi)律(lv)(lv)(lv)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)增加,引(yin)起(qi)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)。Pogwizd等用心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)三維(wei)標測(ce)技術研究(jiu)表明(ming),75%的(de)(de)(de)(de)(de)再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)是由(you)觸發(fa)(fa)激(ji)動(dong)(dong)(dong)(dong)(dong)(dong)引(yin)起(qi)的(de)(de)(de)(de)(de),25%的(de)(de)(de)(de)(de)再(zai)(zai)(zai)(zai)灌(guan)(guan)(guan)注(zhu)(zhu)(zhu)(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)是由(you)折返機(ji)(ji)制引(yin)起(qi)。
病(bing)因不明(ming),無明(ming)顯(xian)冠狀動脈或(huo)(huo)心(xin)肌本身的(de)病(bing)變(bian),常(chang)常(chang)突然或(huo)(huo)在某些誘(you)因的(de)作用(yong)下發(fa)(fa)(fa)生嚴重的(de)室(shi)性(xing)(xing)心(xin)律失(shi)常(chang)和(he)(或(huo)(huo))心(xin)室(shi)顫動,而發(fa)(fa)(fa)生心(xin)臟性(xing)(xing)猝死。研究表(biao)明(ming),原發(fa)(fa)(fa)性(xing)(xing)室(shi)性(xing)(xing)心(xin)律失(shi)常(chang)的(de)發(fa)(fa)(fa)生機制(zhi)多為觸發(fa)(fa)(fa)激動,也有的(de)為折返機制(zhi)。
Raizes等(deng)研(yan)究(jiu)表(biao)明,非心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)常引(yin)起的(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)猝死(si)只(zhi)占0.56%,包括(kuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)或(huo)主動(dong)脈(mo)破裂(lie),心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗死(si)擴(kuo)展,交(jiao)感神(shen)經反射性(xing)抑制(zhi),以及(ji)各種原因(yin)引(yin)起的(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)嚴重的(de)機械(xie)性(xing)梗阻等(deng)。尤其(qi)伴有(you)左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)能(neng)不(bu)(bu)全(quan)的(de)患(huan)者心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)猝死(si)的(de)發(fa)生率最(zui)高。左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)能(neng)不(bu)(bu)全(quan)又常有(you)冠狀動(dong)脈(mo)病(bing)變和彌漫的(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌病(bing)變,因(yin)而(er)可伴有(you)急(ji)性(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌缺(que)血或(huo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌瘢痕組織所(suo)誘發(fa)的(de)惡性(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)常,從而(er)導致心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)猝死(si)。在冠心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)病(bing)合并(bing)左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)功(gong)能(neng)不(bu)(bu)全(quan)致心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)猝死(si)事件中,36%表(biao)現(xian)為(wei)(wei)嚴重心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過緩或(huo)電-機械(xie)分(fen)離。心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)驟(zou)停前并(bing)未伴心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)力(li)衰(shuai)竭癥狀的(de)惡化。緩慢性(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)常或(huo)電-機械(xie)分(fen)離可能(neng)因(yin)左(zuo)室(shi)收(shou)縮(suo)功(gong)能(neng)衰(shuai)竭終(zhong)末(mo)期心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)壁應激時(shi)使(shi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)內壓力(li)和容量突然增加,而(er)周(zhou)圍血管收(shou)縮(suo)同時(shi)出現(xian)障(zhang)礙,不(bu)(bu)能(neng)維持體循(xun)環血壓,以至(zhi)虛脫和暈厥。猝死(si)則為(wei)(wei)血流動(dong)力(li)學障(zhang)礙所(suo)致,并(bing)非心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)電不(bu)(bu)穩定事件。另(ling)一部(bu)分(fen)左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)能(neng)不(bu)(bu)全(quan)的(de)患(huan)者伴有(you)室(shi)性(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過速,則可能(neng)為(wei)(wei)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)常所(suo)致。
(2)心(xin)臟性猝(cu)死后(hou)的(de)病(bing)生(sheng)理變化
原發(fa)性(xing)(xing)改變:心(xin)(xin)臟性(xing)(xing)猝(cu)(cu)死的(de)(de)心(xin)(xin)臟病(bing)(bing)(bing)理(li)改變資(zi)料(liao)主要來(lai)自(zi)尸體(ti)(ti)解剖。但不同學(xue)者(zhe)(zhe)所(suo)報道的(de)(de)尸體(ti)(ti)解剖病(bing)(bing)(bing)理(li)結(jie)果(guo)有(you)(you)很大的(de)(de)不一(yi)致,且多數學(xue)者(zhe)(zhe)研究(jiu)為冠(guan)(guan)心(xin)(xin)病(bing)(bing)(bing)猝(cu)(cu)死。從冠(guan)(guan)心(xin)(xin)病(bing)(bing)(bing)猝(cu)(cu)死的(de)(de)病(bing)(bing)(bing)理(li)資(zi)料(liao)來(lai)看,主要病(bing)(bing)(bing)理(li)結(jie)果(guo)為冠(guan)(guan)狀動(dong)(dong)脈狹窄程度(du)重(zhong),冠(guan)(guan)狀動(dong)(dong)脈內(nei)并發(fa)血栓形成,心(xin)(xin)肌出現嚴重(zhong)的(de)(de)缺血或梗死。Schwartz等發(fa)現,1/3以(yi)上的(de)(de)冠(guan)(guan)心(xin)(xin)病(bing)(bing)(bing)猝(cu)(cu)死患者(zhe)(zhe)的(de)(de)冠(guan)(guan)狀動(dong)(dong)脈內(nei)有(you)(you)血栓形成。國內(nei)外的(de)(de)一(yi)些(xie)資(zi)料(liao)提(ti)示:冠(guan)(guan)心(xin)(xin)病(bing)(bing)(bing)猝(cu)(cu)死患者(zhe)(zhe)中急(ji)性(xing)(xing)心(xin)(xin)肌梗死的(de)(de)發(fa)生(sheng)率約為40%,并且冠(guan)(guan)心(xin)(xin)病(bing)(bing)(bing)猝(cu)(cu)死患者(zhe)(zhe)的(de)(de)竇房(fang)結(jie)和傳導系統并無明顯(xian)的(de)(de)急(ji)性(xing)(xing)病(bing)(bing)(bing)變,亦證實了冠(guan)(guan)心(xin)(xin)病(bing)(bing)(bing)猝(cu)(cu)死的(de)(de)發(fa)生(sheng)機制為心(xin)(xin)電不穩定所(suo)致。心(xin)(xin)臟性(xing)(xing)猝(cu)(cu)死很少發(fa)生(sheng)在(zai)沒有(you)(you)器質性(xing)(xing)心(xin)(xin)臟病(bing)(bing)(bing)的(de)(de)患者(zhe)(zhe)。有(you)(you)些(xie)患者(zhe)(zhe)發(fa)生(sheng)心(xin)(xin)臟性(xing)(xing)猝(cu)(cu)死后,即使心(xin)(xin)臟的(de)(de)大體(ti)(ti)檢查(cha)無明顯(xian)肉(rou)眼病(bing)(bing)(bing)變,但可能其心(xin)(xin)臟的(de)(de)分(fen)子結(jie)構和功(gong)能也存(cun)在(zai)著明顯(xian)的(de)(de)異常(chang)。如離子通(tong)道、蛋白(bai)質結(jie)構異常(chang)等。
繼發性改(gai)變:正常心(xin)(xin)(xin)(xin)臟做功所需能量(liang)首先來(lai)自(zi)脂肪,約(yue)占心(xin)(xin)(xin)(xin)肌(ji)總耗氧量(liang)的(de)(de)67%,其次來(lai)自(zi)葡萄(tao)糖和乳酸(suan)(suan)(suan)(suan),分別占17.9%和16.46%,極(ji)少(shao)數來(lai)自(zi)醋酸(suan)(suan)(suan)(suan)、氨基酸(suan)(suan)(suan)(suan)、丙酮酸(suan)(suan)(suan)(suan)等。同時心(xin)(xin)(xin)(xin)臟必須依賴ATP來(lai)維持其心(xin)(xin)(xin)(xin)室壁的(de)(de)張力和收(shou)縮狀態。研究表明,心(xin)(xin)(xin)(xin)肌(ji)缺(que)(que)血(xue)(xue)缺(que)(que)氧10s即(ji)(ji)可代(dai)謝底物耗竭,心(xin)(xin)(xin)(xin)臟即(ji)(ji)完全(quan)失去收(shou)縮功能。在常溫下,如(ru)(ru)果心(xin)(xin)(xin)(xin)肌(ji)缺(que)(que)血(xue)(xue)3~4min,心(xin)(xin)(xin)(xin)肌(ji)內(nei)磷(lin)(lin)酸(suan)(suan)(suan)(suan)肌(ji)酸(suan)(suan)(suan)(suan)含量(liang)減少(shao)70%~75%,ATP減少(shao)15%。如(ru)(ru)在此(ci)期(qi)內(nei)進行有(you)效的(de)(de)心(xin)(xin)(xin)(xin)肺復(fu)蘇,心(xin)(xin)(xin)(xin)肌(ji)供血(xue)(xue)改(gai)善,則心(xin)(xin)(xin)(xin)肌(ji)張力可完全(quan)恢(hui)復(fu);缺(que)(que)血(xue)(xue)8~10min,心(xin)(xin)(xin)(xin)肌(ji)內(nei)磷(lin)(lin)酸(suan)(suan)(suan)(suan)肌(ji)酸(suan)(suan)(suan)(suan)和ATP將(jiang)全(quan)部耗盡,如(ru)(ru)在此(ci)期(qi)內(nei)進行有(you)效的(de)(de)心(xin)(xin)(xin)(xin)肺復(fu)蘇,心(xin)(xin)(xin)(xin)臟的(de)(de)收(shou)縮和舒張功能仍(reng)可恢(hui)復(fu),10min后才進行有(you)效的(de)(de)心(xin)(xin)(xin)(xin)肺復(fu)蘇者,復(fu)蘇的(de)(de)成功機會顯著減少(shao)。
腦(nao)(nao):腦(nao)(nao)的(de)(de)能量代謝(xie)主要來自葡萄(tao)糖,但腦(nao)(nao)組(zu)織(zhi)本身對(dui)葡萄(tao)糖的(de)(de)儲備很少,必須依賴(lai)(lai)于循環血(xue)(xue)(xue)液(ye)來供應。并且腦(nao)(nao)組(zu)織(zhi)的(de)(de)代謝(xie)85%~90%為(wei)有氧(yang)(yang)(yang)代謝(xie),而(er)無氧(yang)(yang)(yang)酵解只占腦(nao)(nao)組(zu)織(zhi)代謝(xie)的(de)(de)5%~15%,所(suo)以,腦(nao)(nao)組(zu)織(zhi)的(de)(de)代謝(xie)和(he)生(sheng)理功(gong)能的(de)(de)維持(chi)則完(wan)全依賴(lai)(lai)于有效的(de)(de)血(xue)(xue)(xue)液(ye)供應。血(xue)(xue)(xue)液(ye)供應障(zhang)礙引(yin)起腦(nao)(nao)細(xi)(xi)(xi)胞功(gong)能的(de)(de)改變(bian)(bian)的(de)(de)基礎是缺血(xue)(xue)(xue)缺氧(yang)(yang)(yang)引(yin)起腦(nao)(nao)組(zu)織(zhi)的(de)(de)原(yuan)(yuan)發和(he)繼(ji)發損(sun)害。原(yuan)(yuan)發損(sun)害為(wei)腦(nao)(nao)組(zu)織(zhi)缺血(xue)(xue)(xue)缺氧(yang)(yang)(yang)時,ATP不能合成(cheng),細(xi)(xi)(xi)胞鈉泵功(gong)能喪失(shi),細(xi)(xi)(xi)胞內(nei)鈉離子不能轉運到細(xi)(xi)(xi)胞外,鉀(jia)離子不能從細(xi)(xi)(xi)胞內(nei)逸出,細(xi)(xi)(xi)胞膜電(dian)位發生(sheng)改變(bian)(bian),因(yin)此不能產(chan)生(sheng)電(dian)活(huo)動(dong),細(xi)(xi)(xi)胞也失(shi)去(qu)了產(chan)生(sheng)和(he)傳導沖動(dong)的(de)(de)功(gong)能。研究表明,在完(wan)全缺氧(yang)(yang)(yang)情況(kuang)下,20s后大腦(nao)(nao)皮質的(de)(de)生(sheng)物電(dian)活(huo)動(dong)完(wan)全消(xiao)失(shi),30~90s后小腦(nao)(nao)和(he)延髓的(de)(de)生(sheng)物電(dian)活(huo)動(dong)完(wan)全消(xiao)失(shi)。而(er)缺血(xue)(xue)(xue)缺氧(yang)(yang)(yang)所(suo)致的(de)(de)繼(ji)發損(sun)害包括兩個方面:
A.細(xi)胞內電解質紊亂和(he)各種(zhong)代謝(xie)產物的堆積而使腦組織腫脹和(he)腦水腫。
B.腦(nao)(nao)(nao)(nao)組(zu)織(zhi)的局(ju)部循環功能障礙進(jin)一(yi)步加(jia)重。已有研究提示,心臟(zang)驟停(ting)引起(qi)的腦(nao)(nao)(nao)(nao)組(zu)織(zhi)缺(que)(que)血(xue)缺(que)(que)氧(yang)時,病變(bian)主(zhu)要在大(da)腦(nao)(nao)(nao)(nao)海馬回(hui)先出現,如缺(que)(que)血(xue)進(jin)一(yi)步加(jia)重,則迅(xun)速波及(ji)(ji)全腦(nao)(nao)(nao)(nao),包括腦(nao)(nao)(nao)(nao)干和延髓。而患(huan)者發生(sheng)心臟(zang)性猝死后,如果能及(ji)(ji)時、有效(xiao)地進(jin)行(xing)心肺復蘇,則腦(nao)(nao)(nao)(nao)組(zu)織(zhi)的血(xue)流有可能恢(hui)復,但腦(nao)(nao)(nao)(nao)組(zu)織(zhi)由(you)于(yu)受到完全缺(que)(que)血(xue)缺(que)(que)氧(yang)的影響,腦(nao)(nao)(nao)(nao)水腫和微(wei)循環障礙將繼續(xu)發展(zhan)。腦(nao)(nao)(nao)(nao)組(zu)織(zhi)的缺(que)(que)血(xue)缺(que)(que)氧(yang)時間長短(duan)直(zhi)接影響大(da)腦(nao)(nao)(nao)(nao)功能的恢(hui)復及(ji)(ji)患(huan)者的臨床預后。
腎:
心臟驟停時(shi)(shi),腎(shen)臟的(de)血流供應和濾過功能完全停止(zhi)。首先(xian)受累的(de)是腎(shen)小(xiao)管(guan)(guan),引起腎(shen)小(xiao)管(guan)(guan)細胞壞死,并逐步累及基底膜及整(zheng)個腎(shen)單(dan)位。如果發生(sheng)(sheng)時(shi)(shi)間短,基底膜可保持(chi)相(xiang)對(dui)完整(zheng),腎(shen)臟功能可恢復,但缺(que)血缺(que)氧(yang)的(de)時(shi)(shi)間過長,腎(shen)小(xiao)管(guan)(guan)及腎(shen)小(xiao)球(qiu)產生(sheng)(sheng)廣泛的(de)嚴重破壞,則(ze)易發生(sheng)(sheng)急(ji)性腎(shen)功能衰竭。
肺:發生心臟性猝死后(hou),肺可(ke)(ke)發生淤血(xue)(xue)(xue)、水腫(zhong)。顯(xian)微鏡下其主要特征(zheng)是肺間質(zhi)水腫(zhong),并可(ke)(ke)見微血(xue)(xue)(xue)栓(shuan)形(xing)成。長時間的肺缺(que)(que)(que)血(xue)(xue)(xue)缺(que)(que)(que)氧容易發生彌漫性血(xue)(xue)(xue)管內(nei)凝血(xue)(xue)(xue),不(bu)僅(jin)可(ke)(ke)通過(guo)機(ji)械堵塞使(shi)肺部缺(que)(que)(que)血(xue)(xue)(xue)缺(que)(que)(que)氧進一(yi)步(bu)加重,而且(qie)還可(ke)(ke)引起血(xue)(xue)(xue)小板聚集(ji),釋放5-HT等物質(zhi)產生終(zhong)末氣道痙攣,結果(guo)血(xue)(xue)(xue)液-氣體交換障礙進一(yi)步(bu)惡化。
(3)與(yu)心臟(zang)性猝死發生(sheng)的相關因素
自主神(shen)經(jing)系統在心(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)猝(cu)死的(de)(de)(de)發(fa)生(sheng)中具有重(zhong)要作(zuo)用(yong)。臨(lin)床觀察發(fa)現,冠(guan)心(xin)(xin)(xin)(xin)病(bing)患者(zhe)的(de)(de)(de)心(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)猝(cu)死常發(fa)生(sheng)在凌晨(chen)至(zhi)午間(jian)(jian)這(zhe)段(duan)時(shi)間(jian)(jian),與(yu)自主神(shen)經(jing)活(huo)(huo)動的(de)(de)(de)晝夜(ye)節律性(xing)(xing)(xing)變(bian)化相一致(zhi)。此時(shi)間(jian)(jian)段(duan),交感神(shen)經(jing)活(huo)(huo)動較高(gao),血(xue)(xue)(xue)壓與(yu)心(xin)(xin)(xin)(xin)率增(zeng)加,血(xue)(xue)(xue)小板聚(ju)集性(xing)(xing)(xing)也增(zeng)加。實(shi)驗研究表明,刺激心(xin)(xin)(xin)(xin)臟(zang)的(de)(de)(de)交感神(shen)經(jing)可(ke)降低室(shi)(shi)顫閾值(zhi),增(zeng)加室(shi)(shi)顫發(fa)生(sheng)的(de)(de)(de)危險性(xing)(xing)(xing);刺激迷走(zou)神(shen)經(jing),可(ke)降低室(shi)(shi)顫發(fa)生(sheng)的(de)(de)(de)危險性(xing)(xing)(xing)。所以交感神(shen)經(jing)的(de)(de)(de)過度(du)興(xing)奮可(ke)促進(jin)惡性(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)律失常的(de)(de)(de)發(fa)生(sheng),而(er)興(xing)奮迷走(zou)神(shen)經(jing)則具有保護(hu)心(xin)(xin)(xin)(xin)臟(zang)及抗室(shi)(shi)顫的(de)(de)(de)作(zuo)用(yong)。但是,對下后壁急性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)肌缺(que)(que)(que)血(xue)(xue)(xue)或(huo)缺(que)(que)(que)血(xue)(xue)(xue)性(xing)(xing)(xing)再(zai)灌注的(de)(de)(de)患者(zhe),因迷走(zou)神(shen)經(jing)的(de)(de)(de)傳入(ru)受體多數分布在心(xin)(xin)(xin)(xin)室(shi)(shi)的(de)(de)(de)下后壁,該部位發(fa)生(sheng)心(xin)(xin)(xin)(xin)肌缺(que)(que)(que)血(xue)(xue)(xue)或(huo)缺(que)(que)(que)血(xue)(xue)(xue)后再(zai)灌注,可(ke)觸發(fa)Bezold-Jarish反射(she),導致(zhi)或(huo)加重(zhong)緩(huan)(huan)慢性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)律失常,如嚴(yan)重(zhong)竇性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)動過緩(huan)(huan),高(gao)度(du)房室(shi)(shi)傳導阻(zu)滯,周圍血(xue)(xue)(xue)管(guan)擴張和低血(xue)(xue)(xue)壓,嚴(yan)重(zhong)者(zhe)可(ke)發(fa)生(sheng)心(xin)(xin)(xin)(xin)臟(zang)驟停。
許多心(xin)(xin)臟性猝(cu)死的患者發生(sheng)(sheng)在睡眠(mian)中。其(qi)機制主要為睡眠(mian)時迷走神經興奮,冠狀動脈(mo)痙攣,心(xin)(xin)臟傳導系(xi)統發生(sheng)(sheng)缺(que)氧,心(xin)(xin)電不穩定,發生(sheng)(sheng)室顫而(er)引(yin)起心(xin)(xin)臟性猝(cu)死。但目(mu)前尚(shang)未能提(ti)供冠狀動脈(mo)痙攣的形態(tai)學依據(ju)。
(1)心(xin)臟病(bing)發作(zuo)前,身體上例如頸、后(hou)背(bei)、頭皮(pi)、手(shou)心(xin)或者(zhe)腳掌都會大量(liang)出汗(han),此時(shi)(shi)應(ying)提(ti)高警惕,當(dang)心(xin)猝死發生(sheng),最好停止活動(dong)休(xiu)息(xi),及時(shi)(shi)服用藥物,必要時(shi)(shi)應(ying)立即撥(bo)打(da)120。
(2)在無激烈運動、缺少睡眠或者生病(bing)等誘因(yin)的(de)情況下,連續幾(ji)天、幾(ji)周(zhou)甚至幾(ji)月(yue)出(chu)現(xian)極度疲勞(lao)感,伴有焦慮、失眠、無癥狀驚醒等癥狀,此時(shi)應考慮心(xin)臟出(chu)現(xian)問題。
(3)心(xin)臟病患者經常感到肩膀、頸部、下巴、手臂疼痛(tong),這是心(xin)肌(ji)缺血的(de)信號,因為心(xin)肌(ji)缺血疼痛(tong)在傳(chuan)遞至大腦(nao)中樞神經時,會同時反映在水平相同的(de)脊髓段(duan)區域。
(4)心臟病(bing)發作前(qian)的典型癥狀(zhuang)是突然、或者(zhe)無(wu)緣由的心跳加劇(ju),一旦發生心室(shi)性心搏(bo)過速,則極有可(ke)能在短時(shi)間內突然死亡。
(5)很(hen)多心(xin)(xin)(xin)源性猝死(si)患者在死(si)亡前都(dou)反復出現胃腸(chang)道癥狀,不少(shao)人生(sheng)前并沒有胃病病史,這是(shi)心(xin)(xin)(xin)臟(zang)病發作的信號之一,腸(chang)胃不適是(shi)因(yin)為(wei)心(xin)(xin)(xin)血管出現異常。動(dong)脈由于脂肪沉積物堵塞將會(hui)減少(shao)甚至阻斷血液傳輸給(gei)心(xin)(xin)(xin)臟(zang),而這會(hui)引起心(xin)(xin)(xin)絞痛。
心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死的經(jing)過大(da)體(ti)(ti)上(shang)可分(fen)為(wei)4 個時期(qi)。即前驅(qu)期(qi),終末事件(jian)開始,心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)停(ting)(ting)和生物學死亡。不同的患(huan)(huan)者各期(qi)表現(xian)(xian)也有(you)(you)(you)明顯(xian)差異。在(zai)發(fa)生心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死的前數(shu)天到數(shu)月,有(you)(you)(you)些(xie)患(huan)(huan)者可出現(xian)(xian)心(xin)(xin)(xin)(xin)(xin)前區不適(shi)、心(xin)(xin)(xin)(xin)(xin)悸(ji)、氣短(duan)、乏力等(deng)非特異性表現(xian)(xian)。但亦可無前驅(qu)表現(xian)(xian),直接發(fa)生心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)停(ting)(ting)。而(er)有(you)(you)(you)些(xie)報道佩(pei)帶動態心(xin)(xin)(xin)(xin)(xin)電(dian)圖的猝(cu)死患(huan)(huan)者,當時心(xin)(xin)(xin)(xin)(xin)電(dian)記(ji)錄多(duo)為(wei)心(xin)(xin)(xin)(xin)(xin)室顫動,說明心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)停(ting)(ting)時多(duo)為(wei)心(xin)(xin)(xin)(xin)(xin)室顫動。部分(fen)患(huan)(huan)者先有(you)(you)(you)心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)缺(que)血或左室功(gong)能不全癥(zheng)(zheng)狀(zhuang),迅即發(fa)生心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)停(ting)(ting)。心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)停(ting)(ting)前未訴(su)有(you)(you)(you)不適(shi)感覺者,是否有(you)(you)(you)無癥(zheng)(zheng)狀(zhuang)心(xin)(xin)(xin)(xin)(xin)肌缺(que)血則不能確定。心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)停(ting)(ting)后腦血流銳減(jian),可導致意識(shi)突然喪失。下列體(ti)(ti)征有(you)(you)(you)助(zhu)于判斷(duan)(duan)是否發(fa)生心(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)停(ting)(ting):意識(shi)喪失,頸、股(gu)動脈搏動消失,呼吸斷(duan)(duan)續或停(ting)(ting)止(zhi),皮(pi)膚蒼白(bai)或明顯(xian)發(fa)紺。如聽診心(xin)(xin)(xin)(xin)(xin)音消失更可確立診斷(duan)(duan)。經(jing)檢(jian)查(cha)確立診斷(duan)(duan)后,應(ying)立即進(jin)行(xing)有(you)(you)(you)效的心(xin)(xin)(xin)(xin)(xin)肺復蘇。
(1)心電圖
目前(qian)已知(zhi),心肌肥厚是心臟性猝死(si)的(de)(de)標志(zhi)性心電圖。QRS波(bo)群高(gao)電壓和側壁導聯明顯的(de)(de)間(jian)隔部Q波(bo)的(de)(de)出(chu)(chu)現(xian)可能是猝死(si)的(de)(de)危險(xian)(xian)因素。大面積前(qian)壁心肌梗死(si)的(de)(de)患者,心電圖出(chu)(chu)現(xian)右束支(zhi)阻滯,6個(ge)月的(de)(de)猝死(si)風險(xian)(xian)約30%。
(2)動(dong)態心電圖(Holter)
動態心(xin)(xin)(xin)電圖可使39%~82%的(de)室(shi)性(xing)(xing)心(xin)(xin)(xin)律失常(chang)患(huan)者得到診斷,并能了解室(shi)性(xing)(xing)心(xin)(xin)(xin)律失常(chang)的(de)頻(pin)度(du)、復雜程度(du)、晝(zhou)夜節律等(deng)變化(hua),尤其是心(xin)(xin)(xin)肌梗死(si)和嚴(yan)重的(de)冠(guan)心(xin)(xin)(xin)病患(huan)者。動態心(xin)(xin)(xin)電圖發現的(de)室(shi)性(xing)(xing)心(xin)(xin)(xin)律失常(chang)對(dui)心(xin)(xin)(xin)臟性(xing)(xing)猝(cu)死(si)的(de)發生有明確的(de)預測價值。心(xin)(xin)(xin)臟性(xing)(xing)猝(cu)死(si)的(de)危險性(xing)(xing)隨(sui)著(zhu)室(shi)性(xing)(xing)心(xin)(xin)(xin)律失常(chang)的(de)復雜性(xing)(xing)和頻(pin)發性(xing)(xing)而增加。
(3)運動試驗
有研究表明,運動試驗(yan)對心肌梗死(si)后的患(huan)者發生(sheng)心臟性猝死(si)有一(yi)定的預測價值。
(4)心室(shi)晚電位
(ventricular late potential,VLP) 心(xin)室(shi)晚電位是體表記錄(lu)到(dao)的(de)(de)局部(bu)心(xin)室(shi)延(yan)遲碎(sui)裂(lie)電活(huo)動,一(yi)(yi)般(ban)出現(xian)在QRS終末部(bu)并可延(yan)伸到(dao)ST內,呈高頻(pin)(20~80Hz)、低幅(fu)(25V=碎(sui)裂(lie)波),持續10s以上。從目(mu)前(qian)已有的(de)(de)資料來看,心(xin)室(shi)晚電位在預測患者(zhe)發生致命(ming)性(xing)(xing)(xing)快速性(xing)(xing)(xing)心(xin)律失常方面具有一(yi)(yi)定的(de)(de)價(jia)值。Brethard等(deng)報道,冠心(xin)病(bing)患者(zhe)伴(ban)有心(xin)室(shi)晚電位陽性(xing)(xing)(xing)者(zhe),發生心(xin)臟性(xing)(xing)(xing)猝死的(de)(de)危險性(xing)(xing)(xing)比心(xin)室(shi)晚電位陰性(xing)(xing)(xing)者(zhe)高3.3倍。
臨床上(shang)須與暈厥、癔癥或癲(dian)癇相鑒別。
(1)心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死的(de)(de)(de)(de)緊急治(zhi)(zhi)療(liao):①心(xin)(xin)(xin)肺復(fu)蘇(CPR)。早(zao)期(qi)、有(you)(you)效(xiao)的(de)(de)(de)(de)措施至關(guan)重(zhong)要(具體(ti)措施請參閱心(xin)(xin)(xin)肺復(fu)蘇)。②進(jin)(jin)一步(bu)的(de)(de)(de)(de)心(xin)(xin)(xin)臟(zang)生(sheng)命(ming)支持(ACLS)。早(zao)期(qi)除顫(zhan)對改善存活至關(guan)重(zhong)要。大約(yue)40%心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死患者(zhe)在醫務人員到達時發(fa)現有(you)(you)心(xin)(xin)(xin)室顫(zhan)動。目前至少有(you)(you)兩個(ge)正在進(jin)(jin)行的(de)(de)(de)(de)前瞻性(xing)(xing)隨機臨床實驗,研究胺(an)碘酮在院外心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死患者(zhe)對電擊難治(zhi)(zhi)性(xing)(xing)心(xin)(xin)(xin)室顫(zhan)動中的(de)(de)(de)(de)作用(yong)。有(you)(you)一個(ge)實驗的(de)(de)(de)(de)初(chu)步(bu)結果提示胺(an)碘酮是(shi)這類患者(zhe)急診治(zhi)(zhi)療(liao)的(de)(de)(de)(de)有(you)(you)效(xiao)藥物。
(2)心(xin)臟性猝死的預防性治療
一級預防治療:
可聯合使用心(xin)臟性猝死的多種預測因素(su)。
鑒于大多數心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)發(fa)生(sheng)在(zai)冠心(xin)(xin)(xin)病的(de)(de)(de)患(huan)者,減(jian)輕心(xin)(xin)(xin)肌(ji)(ji)缺血(xue)(xue),預(yu)防(fang)心(xin)(xin)(xin)肌(ji)(ji)梗(geng)(geng)(geng)死(si)(si)或縮小(xiao)梗(geng)(geng)(geng)死(si)(si)范圍,改(gai)變心(xin)(xin)(xin)肌(ji)(ji)梗(geng)(geng)(geng)死(si)(si)后心(xin)(xin)(xin)室(shi)重(zhong)構的(de)(de)(de)藥(yao)物應(ying)能減(jian)少(shao)心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)的(de)(de)(de)發(fa)生(sheng)率。早期(qi)研究(jiu)顯示(shi)與藥(yao)物治療相比,外科血(xue)(xue)管(guan)(guan)重(zhong)建,使3支血(xue)(xue)管(guan)(guan)病變及左心(xin)(xin)(xin)室(shi)功能不全的(de)(de)(de)冠心(xin)(xin)(xin)病患(huan)者的(de)(de)(de)心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)下降。最近的(de)(de)(de)研究(jiu)顯示(shi),應(ying)用溶栓藥(yao)和(或)經皮(pi)介(jie)入治療可獲得心(xin)(xin)(xin)肌(ji)(ji)再(zai)灌注和血(xue)(xue)管(guan)(guan)重(zhong)建。已有研究(jiu)證(zheng)實β-阻(zu)滯劑在(zai)預(yu)防(fang)心(xin)(xin)(xin)肌(ji)(ji)梗(geng)(geng)(geng)死(si)(si)存活(huo)者心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)及降低其總(zong)死(si)(si)亡率方面(mian)是有效的(de)(de)(de)。血(xue)(xue)管(guan)(guan)緊(jin)張(zhang)素轉(zhuan)(zhuan)換(huan)酶抑制(zhi)劑(ACEI)在(zai)這方面(mian)的(de)(de)(de)證(zheng)據(ju)要少(shao)一些,但有少(shao)數研究(jiu)提示(shi),血(xue)(xue)管(guan)(guan)緊(jin)張(zhang)素轉(zhuan)(zhuan)換(huan)酶抑制(zhi)劑(ACEI)使左心(xin)(xin)(xin)室(shi)功能不全的(de)(de)(de)患(huan)者的(de)(de)(de)心(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)減(jian)少(shao)。
已有幾個隨(sui)機試驗開始實(shi)施(shi),以(yi)比(bi)較ICD和(he)藥(yao)物對心臟性猝死(si)一級預防(fang)的(de)效果。在多中心自動(dong)(dong)心臟復律(lv)除顫器植入試驗(MADIT)中,對非持續性室(shi)性心動(dong)(dong)過速、心肌梗死(si)后左室(shi)功能(neng)(neng)(neng)差以(yi)及電生(sheng)理(li)檢查時(shi)(shi)可誘發出用普魯卡(ka)因胺不能(neng)(neng)(neng)抑制的(de)室(shi)性心動(dong)(dong)過速患者,ICD比(bi)常規抗(kang)心律(lv)失常藥(yao)物更有效。但最(zui)近報道的(de)冠狀動(dong)(dong)脈旁路移植(CABG)補片試驗(patch trail)證明(ming)給伴左室(shi)功能(neng)(neng)(neng)不全和(he)信號平(ping)均心電圖異常的(de)患者做CABG時(shi)(shi),預防(fang)性植入ICD,并(bing)不能(neng)(neng)(neng)改(gai)善存活。
二級預防治療:
①抗心律失常藥(yao):
心(xin)臟(zang)性(xing)(xing)猝(cu)死的發生機(ji)制主要是(shi)心(xin)室顫動,從理論上講,使用抗心(xin)律失(shi)常(chang)藥(yao)物(wu)控制或消(xiao)除(chu)各種(zhong)室性(xing)(xing)心(xin)律失(shi)常(chang)具有(you)防治心(xin)臟(zang)性(xing)(xing)猝(cu)死的作用,但是(shi),不同(tong)抗心(xin)律失(shi)常(chang)藥(yao)物(wu)的臨床使用結果卻(que)不盡相同(tong)。
Ⅰ類抗(kang)心(xin)律(lv)失(shi)常(chang)藥物一度(du)使用十分廣泛,但到目前為(wei)止,一些大(da)規模隨(sui)機臨床試驗的結果表明,許多Ⅰ類抗(kang)心(xin)律(lv)失(shi)常(chang)藥物的使用并不能降低心(xin)臟性(xing)猝死(si)的發生率,相反卻使心(xin)臟性(xing)猝死(si)的發生率升高,其中,比較典型的是CAST。
CAST即心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)抑制實驗(Cardiac arrhythmic suppression trial,CAST),是一(yi)(yi)(yi)項由美國(guo)國(guo)立心(xin)(xin)(xin)(xin)肺血(xue)液(ye)研究(jiu)(jiu)組織(zhi)的(de)(de)隨機、雙盲對照的(de)(de)多中(zhong)(zhong)心(xin)(xin)(xin)(xin)臨床試(shi)驗。旨(zhi)在確定抗心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥(yao)(yao)物抑制心(xin)(xin)(xin)(xin)肌(ji)梗(geng)死后(hou)(hou)無癥(zheng)狀(zhuang)或伴有(you)(you)(you)輕度(du)癥(zheng)狀(zhuang)的(de)(de)室(shi)(shi)性心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang),并了解能(neng)否(fou)降(jiang)(jiang)(jiang)低(di)心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)所致的(de)(de)病死率(lv)(lv)(lv)。1989年報道的(de)(de)CASTⅠ結(jie)果發(fa)表在《新英格蘭醫院學雜志(zhi)》第321卷上(shang)。這些研究(jiu)(jiu)結(jie)果表明,Ⅰc類抗心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥(yao)(yao)物不僅(jin)不能(neng)降(jiang)(jiang)(jiang)低(di)心(xin)(xin)(xin)(xin)肌(ji)梗(geng)死后(hou)(hou)心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)的(de)(de)發(fa)生率(lv)(lv)(lv),相反卻可使患(huan)者(zhe)(zhe)的(de)(de)心(xin)(xin)(xin)(xin)臟猝(cu)死率(lv)(lv)(lv)增加。其原因可能(neng)與下列2個因素有(you)(you)(you)關,一(yi)(yi)(yi)是Ⅰ類抗心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥(yao)(yao)物本身具有(you)(you)(you)促心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)作用;二是Ⅰc類抗心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥(yao)(yao)物具有(you)(you)(you)不同程度(du)的(de)(de)心(xin)(xin)(xin)(xin)肌(ji)抑制作用,可使患(huan)者(zhe)(zhe)的(de)(de)心(xin)(xin)(xin)(xin)功能(neng)進一(yi)(yi)(yi)步(bu)減退,射血(xue)分數進一(yi)(yi)(yi)步(bu)降(jiang)(jiang)(jiang)低(di)。但(dan)是,CAST僅(jin)僅(jin)是在心(xin)(xin)(xin)(xin)肌(ji)梗(geng)死后(hou)(hou)的(de)(de)室(shi)(shi)性心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)患(huan)者(zhe)(zhe)中(zhong)(zhong)進行的(de)(de),在非心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)的(de)(de)患(huan)者(zhe)(zhe)發(fa)生的(de)(de)室(shi)(shi)性心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)中(zhong)(zhong),Ⅰc類抗心(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥(yao)(yao)物能(neng)否(fou)降(jiang)(jiang)(jiang)低(di)心(xin)(xin)(xin)(xin)臟性猝(cu)死的(de)(de)發(fa)生率(lv)(lv)(lv),目前尚不清(qing)楚。
在(zai)(zai)抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)(wu)中(zhong)(zhong),目前(qian)Ⅲ類抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)(wu)是最受推崇的(de)(de)(de)(de)(de)(de),其(qi)(qi)原因是這些藥(yao)(yao)物(wu)(wu)不僅能(neng)有(you)(you)(you)效(xiao)控制各種室(shi)(shi)(shi)性(xing)(xing)(xing)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang),而且一(yi)(yi)些多中(zhong)(zhong)心(xin)隨(sui)(sui)機(ji)臨(lin)床(chuang)試(shi)驗(yan)(yan)結(jie)(jie)果表明(ming)(ming)胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong),長期(qi)口服時(shi)能(neng)增加(jia)各種心(xin)肌(ji)(ji)(ji)(ji)組(zu)織的(de)(de)(de)(de)(de)(de)動(dong)(dong)作電(dian)位時(shi)程和(he)(he)(he)有(you)(you)(you)效(xiao)不應期(qi),對各種室(shi)(shi)(shi)上(shang)性(xing)(xing)(xing)和(he)(he)(he)室(shi)(shi)(shi)性(xing)(xing)(xing)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang),包括心(xin)房顫動(dong)(dong)、心(xin)房撲動(dong)(dong)和(he)(he)(he)室(shi)(shi)(shi)上(shang)性(xing)(xing)(xing)心(xin)動(dong)(dong)過速等都有(you)(you)(you)較好的(de)(de)(de)(de)(de)(de)效(xiao)果。口服劑量(liang)為(wei)(wei)200~800mg/d,,胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)除(chu)了Ⅲ類抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)(wu)的(de)(de)(de)(de)(de)(de)特(te)(te)性(xing)(xing)(xing)外,還有(you)(you)(you)Ⅰ類抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)(wu)作用(yong)(yong),表現為(wei)(wei)使用(yong)(yong)依賴(lai)性(xing)(xing)(xing)動(dong)(dong)力學(xue)特(te)(te)征,并具(ju)(ju)有(you)(you)(you)一(yi)(yi)定的(de)(de)(de)(de)(de)(de)阻滯(zhi)作用(yong)(yong)和(he)(he)(he)鈣通(tong)道阻滯(zhi)作用(yong)(yong),其(qi)(qi)主要代謝產物(wu)(wu)脫乙基胺(an)(an)(an)(an)腆酮(tong)(tong)(tong)仍具(ju)(ju)有(you)(you)(you)抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)作用(yong)(yong)。胺(an)(an)(an)(an)腆酮(tong)(tong)(tong)和(he)(he)(he)Ⅰc類抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)(wu)不同,除(chu)了發(fa)揮抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)作用(yong)(yong)之外,還有(you)(you)(you)冠狀動(dong)(dong)脈擴張作用(yong)(yong)、抗(kang)(kang)(kang)(kang)交感(gan)神經的(de)(de)(de)(de)(de)(de)激(ji)活作用(yong)(yong)和(he)(he)(he)抗(kang)(kang)(kang)(kang)甲狀腺作用(yong)(yong)。近年來,一(yi)(yi)些研究發(fa)現胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)還有(you)(you)(you)抗(kang)(kang)(kang)(kang)氧化作用(yong)(yong)和(he)(he)(he)拮抗(kang)(kang)(kang)(kang)鈣調節蛋(dan)白的(de)(de)(de)(de)(de)(de)作用(yong)(yong)。在(zai)(zai)心(xin)肌(ji)(ji)(ji)(ji)缺血(xue)時(shi),胺(an)(an)(an)(an)腆酮(tong)(tong)(tong)能(neng)保護線粒體的(de)(de)(de)(de)(de)(de)完整性(xing)(xing)(xing)和(he)(he)(he)高能(neng)磷酸鹽的(de)(de)(de)(de)(de)(de)功(gong)能(neng)。因此,從理論上(shang)講,胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)在(zai)(zai)室(shi)(shi)(shi)性(xing)(xing)(xing)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)的(de)(de)(de)(de)(de)(de)防治中(zhong)(zhong)具(ju)(ju)有(you)(you)(you)自己(ji)獨特(te)(te)的(de)(de)(de)(de)(de)(de)治療(liao)(liao)(liao)(liao)價值。“巴塞(sai)爾心(xin)肌(ji)(ji)(ji)(ji)梗(geng)幸存(cun)者(zhe)的(de)(de)(de)(de)(de)(de)抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)研究(Basel antiarrhythmic study of infarction survival,BASIS)”在(zai)(zai)臨(lin)床(chuang)實踐中(zhong)(zhong)提示胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)在(zai)(zai)心(xin)臟(zang)性(xing)(xing)(xing)猝(cu)死(si)(si)防治中(zhong)(zhong)的(de)(de)(de)(de)(de)(de)價值。BASIS由(you)瑞士學(xue)者(zhe)完成(cheng),入(ru)選(xuan)病(bing)例為(wei)(wei)心(xin)肌(ji)(ji)(ji)(ji)梗(geng)死(si)(si)后8~24天并伴有(you)(you)(you)室(shi)(shi)(shi)性(xing)(xing)(xing)期(qi)前(qian)收(shou)縮(suo)在(zai)(zai)Lown氏分級(ji)4~6級(ji)的(de)(de)(de)(de)(de)(de)患者(zhe)。321例患者(zhe)被隨(sui)(sui)機(ji)分為(wei)(wei)2組(zu),分別用(yong)(yong)安(an)慰劑、胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)和(he)(he)(he)其(qi)(qi)他(ta)抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)(wu)治療(liao)(liao)(liao)(liao),結(jie)(jie)果胺(an)(an)(an)(an)腆酮(tong)(tong)(tong)治療(liao)(liao)(liao)(liao)組(zu)的(de)(de)(de)(de)(de)(de)心(xin)臟(zang)性(xing)(xing)(xing)猝(cu)死(si)(si)率(lv)為(wei)(wei)5%,顯著低于安(an)慰劑治療(liao)(liao)(liao)(liao)組(zu)的(de)(de)(de)(de)(de)(de)11.4%t和(he)(he)(he)其(qi)(qi)他(ta)抗(kang)(kang)(kang)(kang)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)(wu)治療(liao)(liao)(liao)(liao)組(zu)的(de)(de)(de)(de)(de)(de)9%。此外,另外兩項大(da)規模隨(sui)(sui)機(ji)臨(lin)床(chuang)試(shi)驗(yan)(yan)“加(jia)拿大(da)胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)心(xin)肌(ji)(ji)(ji)(ji)梗(geng)死(si)(si)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)試(shi)驗(yan)(yan)(Canadian amiodarone myocardial infarction arrhythmia trial,CAMIAT)”和(he)(he)(he)歐洲心(xin)肌(ji)(ji)(ji)(ji)梗(geng)死(si)(si)胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)試(shi)驗(yan)(yan)“European myocardial infarction amiodarone trial,EMIAT)”正(zheng)在(zai)(zai)進行,最后結(jie)(jie)果尚(shang)未揭曉。CAMLAT有(you)(you)(you)21個醫學(xue)中(zhong)(zhong)心(xin)參(can)加(jia),計劃入(ru)選(xuan)心(xin)肌(ji)(ji)(ji)(ji)梗(geng)死(si)(si)后6~45天伴室(shi)(shi)(shi)性(xing)(xing)(xing)期(qi)前(qian)收(shou)縮(suo)10次/h以上(shang)或室(shi)(shi)(shi)性(xing)(xing)(xing)心(xin)動(dong)(dong)過速1次以上(shang)的(de)(de)(de)(de)(de)(de)患者(zhe),隨(sui)(sui)機(ji)分為(wei)(wei)胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)治療(liao)(liao)(liao)(liao)組(zu)和(he)(he)(he)安(an)慰劑治療(liao)(liao)(liao)(liao)組(zu),預試(shi)完成(cheng)77例,20個月(yue)的(de)(de)(de)(de)(de)(de)觀(guan)察表明(ming)(ming),胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)治療(liao)(liao)(liao)(liao)組(zu)的(de)(de)(de)(de)(de)(de)病(bing)死(si)(si)率(lv)4%而安(an)慰劑治療(liao)(liao)(liao)(liao)組(zu)的(de)(de)(de)(de)(de)(de)病(bing)死(si)(si)率(lv)14%。EMIAT由(you)61個醫學(xue)中(zhong)(zhong)心(xin)參(can)加(jia),計劃入(ru)選(xuan)心(xin)肌(ji)(ji)(ji)(ji)梗(geng)死(si)(si)后5~21天、左心(xin)室(shi)(shi)(shi)射血(xue)分數在(zai)(zai)40%以下的(de)(de)(de)(de)(de)(de)室(shi)(shi)(shi)性(xing)(xing)(xing)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)患者(zhe),隨(sui)(sui)機(ji)分為(wei)(wei)安(an)慰劑治療(liao)(liao)(liao)(liao)組(zu)和(he)(he)(he)胺(an)(an)(an)(an)碘(dian)酮(tong)(tong)(tong)治療(liao)(liao)(liao)(liao)組(zu)。中(zhong)(zhong)期(qi)結(jie)(jie)果表明(ming)(ming),胺(an)(an)(an)(an)腆酮(tong)(tong)(tong)可顯著降低心(xin)肌(ji)(ji)(ji)(ji)梗(geng)死(si)(si)后室(shi)(shi)(shi)性(xing)(xing)(xing)心(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)患者(zhe)的(de)(de)(de)(de)(de)(de)心(xin)臟(zang)性(xing)(xing)(xing)猝(cu)死(si)(si)率(lv)。
索(suo)他(ta)洛爾(er)(sotalol)與胺(an)碘酮相似,也具有混合性抗心律(lv)失(shi)常作用。許多學者(zhe)的臨床(chuang)觀察(cha)表明,索(suo)他(ta)洛爾(er)對心律(lv)失(shi)常患者(zhe)的生(sheng)存有益,但還(huan)缺乏長(chang)期多中心臨床(chuang)試驗的結果。
②β-腎(shen)上(shang)腺素(su)受(shou)體阻滯藥(yao):β-腎(shen)上(shang)腺能(neng)受(shou)體阻滯藥(yao)的(de)作(zuo)用在于競爭心臟,血管和支氣管等組織器(qi)官(guan)β腎(shen)上(shang)的(de)腺素(su)能(neng)受(shou)體,使受(shou)體不能(neng)恢復到高(gao)親(qin)和力狀態(tai)而(er)與激(ji)動劑結合(he),從而(er)抑(yi)制(zhi)β腎(shen)上(shang)腺素(su)能(neng)受(shou)體的(de)活(huo)性而(er)發揮一(yi)系列(lie)的(de)藥(yao)理作(zuo)用。
β受體阻滯藥在(zai)心臟(zang)(zang)(zang)性猝死中的(de)應用價值(zhi)仍有爭議,但多數學(xue)者(zhe)認為在(zai)一些心臟(zang)(zang)(zang)的(de)某一亞組可(ke)使心臟(zang)(zang)(zang)性猝死的(de)發(fa)生率降低。
到目前(qian)為止,已(yi)有(you)大(da)量的(de)研(yan)究提示,心(xin)肌(ji)(ji)梗死(si)(si)(si)(si)后的(de)患(huan)(huan)者接受β受體阻滯(zhi)(zhi)劑(ji)(ji)治(zhi)療非常有(you)益,特別是在(zai)降(jiang)(jiang)低(di)(di)心(xin)臟性猝(cu)死(si)(si)(si)(si)方面有(you)較顯著的(de)意義,并且還有(you)人發(fa)(fa)現,在(zai)一定范圍內(nei)心(xin)率(lv)降(jiang)(jiang)得越(yue)慢效果越(yue)明(ming)顯。已(yi)有(you)2項多中(zhong)心(xin)隨(sui)機臨床試(shi)驗-(MIAMI)和(he)(ISIS-I)觀察了(le)β受體阻滯(zhi)(zhi)劑(ji)(ji)在(zai)胸(xiong)痛發(fa)(fa)作12~24h內(nei)早(zao)期干預的(de)作用(yong)。MIAMI入(ru)選(xuan)胸(xiong)痛發(fa)(fa)作24h以內(nei)的(de)心(xin)肌(ji)(ji)梗死(si)(si)(si)(si)患(huan)(huan)者5778例(li),首(shou)先(xian)(xian)使(shi)用(yong)美托洛爾15mg靜脈(mo)注(zhu)射,然后200mg/d口(kou)服,1周病(bing)死(si)(si)(si)(si)率(lv)下降(jiang)(jiang)13%。ISIS-I入(ru)選(xuan)胸(xiong)痛發(fa)(fa)作12h內(nei)的(de)心(xin)肌(ji)(ji)梗死(si)(si)(si)(si)患(huan)(huan)者16000例(li),首(shou)先(xian)(xian)靜脈(mo)注(zhu)射阿替洛爾5~10mg,然后每(mei)周口(kou)服100mg,1周內(nei)心(xin)血管(guan)病(bing)死(si)(si)(si)(si)率(lv)下降(jiang)(jiang)15%。β-受體阻滯(zhi)(zhi)藥的(de)作用(yong)主要是降(jiang)(jiang)低(di)(di)了(le)心(xin)室顫動或心(xin)臟破裂的(de)發(fa)(fa)生率(lv)。在(zai)心(xin)肌(ji)(ji)梗死(si)(si)(si)(si)的(de)后期,使(shi)用(yong)β-受體阻滯(zhi)(zhi)藥可使(shi)心(xin)血管(guan)總病(bing)死(si)(si)(si)(si)率(lv)降(jiang)(jiang)低(di)(di)20%~25%,但對心(xin)臟性猝(cu)死(si)(si)(si)(si)發(fa)(fa)生率(lv)的(de)影響(xiang)尚不清楚。
在高血壓(ya)患者中,β-受(shou)體阻(zu)(zu)(zu)滯(zhi)(zhi)藥(yao)治(zhi)療也(ye)對心(xin)臟性(xing)猝(cu)死具有防治(zhi)作(zuo)用。但更多的(de)(de)學者認為,只有脂溶性(xing)的(de)(de)β-受(shou)體阻(zu)(zu)(zu)滯(zhi)(zhi)藥(yao)如美(mei)托洛爾(er)才能有效地(di)降低心(xin)臟性(xing)猝(cu)死的(de)(de)發(fa)生率。脂溶性(xing)β-受(shou)體阻(zu)(zu)(zu)滯(zhi)(zhi)藥(yao)在消化道易于(yu)吸收,易于(yu)通過血腦屏(ping)障,在中樞神經(jing)系統可以達到較高的(de)(de)血藥(yao)濃度。一(yi)些小樣(yang)本研究提示,選擇性(xing)β-受(shou)體阻(zu)(zu)(zu)滯(zhi)(zhi)藥(yao)美(mei)托洛爾(er)和(he)阿替爾(er)對心(xin)臟性(xing)猝(cu)死的(de)(de)防治(zhi)有效。
③正性(xing)肌力藥物:
在(zai)充(chong)血(xue)性(xing)心(xin)(xin)力(li)(li)衰竭(jie)患者(zhe)中,心(xin)(xin)臟性(xing)猝死(si)的(de)(de)(de)發生很高。1993年,Goldman等報道,冠心(xin)(xin)病引起的(de)(de)(de)充(chong)血(xue)性(xing)心(xin)(xin)力(li)(li)衰竭(jie)患者(zhe)中44%死(si)于心(xin)(xin)臟性(xing)猝死(si);非(fei)冠心(xin)(xin)病引起的(de)(de)(de)充(chong)血(xue)性(xing)心(xin)(xin)力(li)(li)衰竭(jie)患者(zhe)中,心(xin)(xin)臟性(xing)猝死(si)的(de)(de)(de)發生率為48%。因此,正性(xing)肌力(li)(li)藥物在(zai)心(xin)(xin)臟性(xing)猝死(si)防治(zhi)中的(de)(de)(de)價值受到人(ren)們的(de)(de)(de)關注。
正性肌力(li)藥物(wu)(wu)主要包括兩類,即洋地(di)黃類藥物(wu)(wu)和cAMP依賴性強心劑。
洋(yang)地(di)黃類(lei)藥(yao)物仍是(shi)(shi)目(mu)前(qian)治療心(xin)力(li)衰竭的(de)(de)(de)基本藥(yao)物。近年來(lai)的(de)(de)(de)研(yan)究(jiu)表明(ming),洋(yang)地(di)黃類(lei)藥(yao)物不(bu)(bu)僅(jin)能增強(qiang)心(xin)肌收縮力(li)、減慢心(xin)率和傳導,而且具(ju)有神(shen)經內分泌調節作用,可(ke)(ke)改善(shan)心(xin)力(li)衰竭患者(zhe)的(de)(de)(de)壓力(li)感(gan)(gan)受器(qi)功(gong)能低(di)下和交感(gan)(gan)神(shen)經系(xi)統(tong)(tong)、腎素-血管緊張素-醛固酮(tong)系(xi)統(tong)(tong)的(de)(de)(de)功(gong)能亢進,并可(ke)(ke)提高(gao)心(xin)鈉素的(de)(de)(de)分泌,降(jiang)低(di)心(xin)臟前(qian)負荷。盡管洋(yang)地(di)黃的(de)(de)(de)應用已有200多年的(de)(de)(de)歷史,但他在充血性心(xin)力(li)衰竭治療中是(shi)(shi)否(fou)能降(jiang)低(di)心(xin)臟性猝死的(de)(de)(de)發生率仍不(bu)(bu)十分清(qing)楚。1998年以(yi)來(lai),已有幾項大規模隨機(ji)臨床試驗結(jie)果可(ke)(ke)直接(jie)或間(jian)接(jie)反映(ying)地(di)高(gao)辛(xin)治療心(xin)力(li)衰竭是(shi)(shi)有效的(de)(de)(de),不(bu)(bu)僅(jin)能改善(shan)充血性心(xin)力(li)衰竭的(de)(de)(de)癥狀,而且可(ke)(ke)以(yi)提高(gao)患者(zhe)的(de)(de)(de)運動量和心(xin)功(gong)能,但均未闡明(ming)地(di)高(gao)辛(xin)對心(xin)臟性猝死的(de)(de)(de)防治作用。
CAMP依(yi)賴性(xing)(xing)強(qiang)心(xin)(xin)劑包括(kuo):受體激動劑和(he)磷(lin)酸二(er)酯酶(mei)Ⅲ抑制劑。前者主要多巴酚(fen)丁胺、沙丁胺醇等;后者包括(kuo)氨力(li)農。米力(li)農。臨床實踐的結果表明(ming),cAMP依(yi)賴性(xing)(xing)強(qiang)心(xin)(xin)劑在增強(qiang)心(xin)(xin)肌(ji)收縮力(li)和(he)改善患者的癥狀方面(mian)具有一度的療效(xiao),但口(kou)服(fu)給(gei)藥的不良反應較(jiao)多,而且可增加心(xin)(xin)臟性(xing)(xing)猝死(si)的發(fa)生(sheng)率。因此(ci),氨力(li)農和(he)米力(li)農等藥物的口(kou)服(fu)給(gei)藥已經禁止采用。
④抗血小板藥:
A.臨床(chuang)常用的抗血小(xiao)板藥物及其作(zuo)用原理:
抗血(xue)小板(ban)藥物(wu)(wu)(wu)是(shi)指能(neng)阻礙(ai)血(xue)小板(ban)黏附、聚集和釋放反應,以(yi)防止(zhi)血(xue)栓形(xing)成的(de)藥物(wu)(wu)(wu)。根據作用的(de)環節,常(chang)用的(de)抗血(xue)小板(ban)藥物(wu)(wu)(wu)包(bao)括(kuo)以(yi)下幾類:
a.環氧化酶抑制藥:
包括(kuo)阿司匹林(aspirin)、磺吡酮(苯磺唑酮)等。阿司匹林是一種非甾(zai)體抗炎藥,1971年(nian)發現它有抑(yi)制環氧化(hua)酶的作用,目前已成為最常(chang)用的抗血小板藥物。
花生(sheng)四烯酸在(zai)環(huan)氧(yang)(yang)化酶(即前(qian)列(lie)腺素(su)合(he)成酶)的作用(yong)下形成不穩(wen)定的環(huan)內過氧(yang)(yang)化物(wu),即前(qian)列(lie)腺素(su)C2(PGG2)和前(qian)列(lie)腺素(su)H2(PGH2)。環(huan)內過氧(yang)(yang)化物(wu)在(zai)血(xue)小板微粒體(ti)中血(xue)栓(shuan)烷合(he)酶的作用(yong)下生(sheng)成血(xue)栓(shuan)素(su)A2(TXA2),但TXA2不穩(wen)定,半衰期為30s,迅速轉變為穩(wen)定的TXB2。在(zai)血(xue)管壁微粒體(ti)中,環(huan)內過氧(yang)(yang)化物(wu)在(zai)6(9)-環(huan)氧(yang)(yang)化酶作用(yong)下合(he)成前(qian)列(lie)腺素(su)I2(PGl2),然后代謝為6-酮-PGFla。TAX2使血(xue)管收縮,降低血(xue)小板cAMP,促進血(xue)小板聚(ju)集和血(xue)栓(shuan)形成。
阿司(si)匹(pi)(pi)(pi)林(lin)主要抑(yi)(yi)制環(huan)氧(yang)化酶,使其活性基團乙(yi)酰化,從而(er)阻止TXA2和PGI2的(de)(de)生成。由于阿司(si)匹(pi)(pi)(pi)林(lin)在抑(yi)(yi)制TXB2的(de)(de)同時,也對PGI2造成了抑(yi)(yi)制,則阿司(si)匹(pi)(pi)(pi)林(lin)使用的(de)(de)有(you)益作(zuo)用被(bei)削弱或抵消。大量研究表明,75~325mg/d的(de)(de)阿司(si)匹(pi)(pi)(pi)林(lin)給藥對PGI2的(de)(de)影(ying)響較弱或幾乎沒有(you)影(ying)響,而(er)對TXB2的(de)(de)仍(reng)有(you)明顯的(de)(de)抑(yi)(yi)制作(zuo)用。
磺吡酮(tong)(苯磺唑酮(tong))是保太松類(lei)藥物(wu)的(de)(de)(de)衍生物(wu),1950年(nian)被用于治(zhi)療痛風,1965年(nian)發現(xian)它對血(xue)小(xiao)板功能具有明顯影響(xiang)。現(xian)已知(zhi)道,主(zhu)要抑(yi)制血(xue)小(xiao)板的(de)(de)(de)環氧化酶而抑(yi)制TXA2的(de)(de)(de)合(he)成,并(bing)可抑(yi)制血(xue)小(xiao)板的(de)(de)(de)聚集和釋(shi)放(fang)反應。對血(xue)管內皮細(xi)胞合(he)成的(de)(de)(de)PGI2影響(xiang)極小(xiao)。
b.磷酸二酯酶(mei)抑制(zhi)藥:
包括雙(shuang)嘧達莫(persantine)等(deng)(deng)。雙(shuang)嘧達莫又叫潘生丁,是一種廣(guang)泛(fan)應(ying)用于(yu)臨床的抗血小(xiao)板藥物,其(qi)機制(zhi)是抑(yi)(yi)制(zhi)血小(xiao)板的磷酸二酯酶,使血小(xiao)板的cAMP含量升高。同(tong)時(shi),雙(shuang)嘧達莫(潘生丁)還可(ke)通過增加血液的腺(xian)苷(gan)濃度而抑(yi)(yi)制(zhi)血小(xiao)板的聚集和釋放反應(ying)。潘生丁可(ke)抑(yi)(yi)制(zhi)紅(hong)細胞和心、肺(fei)等(deng)(deng)組織細胞對(dui)血中腺(xian)苷(gan)的攝取。則腺(xian)苷(gan)不能被腺(xian)苷(gan)脫胺(an)酶所破壞,血液中腺(xian)苷(gan)水平(ping)增加,一般口服給藥,每次400mg,1~2次/d。主要(yao)不良反應(ying)為胃腸(chang)道癥狀。
c.血栓合成(cheng)酶(mei)抑(yi)制藥(yao):
包括水(shui)楊酸咪唑(zuo)(咪唑(zuo))、達唑(zuo)氧苯(dazoxiben)、對乙(yi)酰氨基(ji)酚(APA)等。
d.腺苷(gan)酸環化酶(mei)激活劑:
依前列醇(前列腺(xian)素I2)和前列地(di)爾(前列腺(xian)素E1) 等(deng)。
e.其他:
噻(sai)氯(lv)匹定(噻(sai)氯(lv)吡(bi)啶)、舒洛地爾(er)(suloctidil)等。
B.抗(kang)血小板藥物防(fang)治心臟(zang)性(xing)猝死的價值(zhi):
在(zai)抗血(xue)小(xiao)板藥物的(de)研究中(zhong),較(jiao)多(duo)的(de)資料為(wei)阿(a)(a)司匹林(lin)(lin)。許多(duo)研究表明(ming),阿(a)(a)司匹林(lin)(lin)在(zai)穩定性(xing)和不穩定性(xing)心(xin)(xin)絞痛患(huan)者(zhe)中(zhong)的(de)應(ying)用(yong)后,可(ke)顯(xian)著(zhu)降(jiang)低(di)(di)致(zhi)死(si)(si)(si)(si)(si)性(xing)和非致(zhi)死(si)(si)(si)(si)(si)性(xing)心(xin)(xin)肌(ji)梗(geng)(geng)死(si)(si)(si)(si)(si)的(de)發(fa)生(sheng)率;在(zai)心(xin)(xin)肌(ji)梗(geng)(geng)死(si)(si)(si)(si)(si)患(huan)者(zhe)應(ying)用(yong)后,可(ke)顯(xian)著(zhu)降(jiang)低(di)(di)再梗(geng)(geng)死(si)(si)(si)(si)(si)的(de)發(fa)生(sheng)率。但(dan)是,有關阿(a)(a)司匹林(lin)(lin)防(fang)治(zhi)心(xin)(xin)臟(zang)(zang)病猝(cu)死(si)(si)(si)(si)(si)的(de)價值,不同學者(zhe)的(de)報(bao)道(dao)(dao)不盡(jin)一(yi)致(zhi)。德國(guo)-奧地利多(duo)中(zhong)心(xin)(xin)研究結果提示,阿(a)(a)司匹林(lin)(lin)對(dui)(dui)心(xin)(xin)臟(zang)(zang)性(xing)猝(cu)死(si)(si)(si)(si)(si)的(de)防(fang)治(zhi)有一(yi)定作(zuo)用(yong)。Elwood等報(bao)道(dao)(dao)用(yong)阿(a)(a)司匹林(lin)(lin)治(zhi)療心(xin)(xin)肌(ji)梗(geng)(geng)死(si)(si)(si)(si)(si)進行(xing)隨機、雙盲大宗病例研究的(de)結果,發(fa)現在(zai)心(xin)(xin)肌(ji)梗(geng)(geng)死(si)(si)(si)(si)(si)后6周以內使用(yong)阿(a)(a)司匹林(lin)(lin)者(zhe),33個月隨訪期間的(de)心(xin)(xin)臟(zang)(zang)性(xing)猝(cu)死(si)(si)(si)(si)(si)率在(zai)阿(a)(a)司匹林(lin)(lin)組為(wei)7.8%、安慰劑組為(wei)13.5%,阿(a)(a)司匹林(lin)(lin)組心(xin)(xin)臟(zang)(zang)性(xing)猝(cu)死(si)(si)(si)(si)(si)的(de)發(fa)生(sheng)率降(jiang)低(di)(di)了42%。如(ru)果阿(a)(a)司匹林(lin)(lin)的(de)使用(yong)時(shi)間較(jiao)晚則對(dui)(dui)心(xin)(xin)臟(zang)(zang)性(xing)猝(cu)死(si)(si)(si)(si)(si)的(de)發(fa)生(sheng)率無明(ming)顯(xian)作(zuo)用(yong)。
雙(shuang)嘧(mi)達(da)莫(潘(pan)生(sheng)丁)在心(xin)臟性(xing)猝(cu)死防治中(zhong)的(de)評價研究多為與阿(a)(a)司匹(pi)林聯合(he)應用。雙(shuang)嘧(mi)達(da)莫(潘(pan)生(sheng)丁)和(he)阿(a)(a)司匹(pi)林的(de)再梗死研究(PARIS)的(de)結果(guo)提示(shi),雙(shuang)嘧(mi)達(da)莫(潘(pan)生(sheng)丁)和(he)阿(a)(a)司匹(pi)林合(he)用可降低心(xin)肌梗死后的(de)總(zong)病死率和(he)心(xin)臟性(xing)猝(cu)死發(fa)生(sheng)率。
磺(huang)吡(bi)酮(tong)(苯磺(huang)唑酮(tong))在(zai)(zai)心臟(zang)性(xing)(xing)猝(cu)死(si)防治中的價(jia)值研究不多(duo)。美國磺(huang)吡(bi)酮(tong)(苯磺(huang)唑酮(tong))研究組報道,在(zai)(zai)6個月內,磺(huang)吡(bi)酮(tong)(苯磺(huang)唑酮(tong))可顯著降低心臟(zang)性(xing)(xing)猝(cu)死(si)的發生率;而在(zai)(zai)6個月后對心臟(zang)性(xing)(xing)猝(cu)死(si)的發生率無明(ming)顯影響。
⑤血管(guan)緊張素轉換酶(mei)抑制藥:
血(xue)管緊張素轉換酶抑制藥(yao)(angiotensin converting enzyme inhibitor,ACEI)是(shi)目前世界上發(fa)展最快(kuai)的(de)(de)一(yi)(yi)類心(xin)血(xue)管藥(yao)物,目前在(zai)臨(lin)床上得到(dao)廣泛應用,許多研究發(fa)現,ACEI對心(xin)肌(ji)梗(geng)死(si)、高血(xue)壓和充血(xue)性心(xin)力衰竭等疾病可(ke)能并發(fa)的(de)(de)心(xin)臟(zang)性猝死(si)具(ju)有一(yi)(yi)定(ding)的(de)(de)防(fang)治作用。
目(mu)前(qian)(qian),ACEI已發展到幾(ji)十種(zhong)。根據其(qi)含有(you)(you)的(de)基(ji)(ji)團不同,ACEI可分(fen)為3種(zhong)類型:A.含巰基(ji)(ji)的(de)ACEI。主要(yao)有(you)(you)卡托普(pu)(pu)(pu)利(li)(li)(li)(captopril);B.含羥(qian)基(ji)(ji)的(de)ACEI。主要(yao)有(you)(you)依那普(pu)(pu)(pu)利(li)(li)(li)(enalapril)、雷米普(pu)(pu)(pu)利(li)(li)(li)(ramipril)、貝那普(pu)(pu)(pu)利(li)(li)(li)(苯拉(la)普(pu)(pu)(pu)利(li)(li)(li))等。C.含磷酰(xian)基(ji)(ji)的(de)ACEI。主要(yao)有(you)(you)福辛普(pu)(pu)(pu)利(li)(li)(li)(fosinopril)等。其(qi)基(ji)(ji)本作(zuo)(zuo)用機制是(shi)抑制血(xue)(xue)管緊張(zhang)素(su)(su)轉(zhuan)換酶(mei)(mei),血(xue)(xue)管緊張(zhang)素(su)(su)轉(zhuan)換酶(mei)(mei)是(shi)一種(zhong)含有(you)(you)鋅離(li)子(zi)(zi)的(de)金屬蛋白,各個活性(xing)(xing)部位(wei)都(dou)含有(you)(you)鋅離(li)子(zi)(zi),ACEI的(de)巰基(ji)(ji)、羥(qian)基(ji)(ji)或磷酰(xian)基(ji)(ji)可與鋅離(li)子(zi)(zi)發生(sheng)牢(lao)固(gu)的(de)絡(luo)合作(zuo)(zuo)用而使(shi)(shi)血(xue)(xue)管緊張(zhang)素(su)(su)轉(zhuan)換酶(mei)(mei)失(shi)(shi)去活性(xing)(xing)。結果血(xue)(xue)管緊張(zhang)素(su)(su)Ⅰ不能(neng)轉(zhuan)變為血(xue)(xue)管緊張(zhang)素(su)(su)Ⅱ,可導致(zhi)血(xue)(xue)管擴張(zhang)、醛固(gu)酮分(fen)泌減少(shao)(shao)和交感神經(jing)張(zhang)力降(jiang)低(di)。此外(wai),ACEI還(huan)可抑制激(ji)肽酶(mei)(mei),減慢緩激(ji)肽的(de)降(jiang)解,引起(qi)血(xue)(xue)管擴張(zhang);同時,緩激(ji)肽的(de)濃度增(zeng)高可激(ji)活前(qian)(qian)磷脂(zhi)酶(mei)(mei)而使(shi)(shi)前(qian)(qian)列腺素(su)(su)的(de)生(sheng)成(cheng)增(zeng)加。ACEI還(huan)可減少(shao)(shao)鈣(gai)離(li)子(zi)(zi)內流,使(shi)(shi)心肌細胞內鈣(gai)離(li)子(zi)(zi)超負荷而引起(qi)的(de)心律失(shi)(shi)常減少(shao)(shao)。這(zhe)些作(zuo)(zuo)用對于冠心病、高血(xue)(xue)壓病和充血(xue)(xue)性(xing)(xing)心力衰竭(jie)等具(ju)有(you)(you)治(zhi)療價(jia)值,還(huan)可增(zeng)加心肌細胞電活動的(de)穩定性(xing)(xing)。
⑥代謝類藥物:
曲美他嗪(萬(wan)爽力(li)),抑制心(xin)(xin)肌(ji)(ji)細胞線粒體內脂肪酸的氧化,加速糖(tang)原酵解(jie),增加心(xin)(xin)肌(ji)(ji)細胞無氧代謝下ATP的產生,增強心(xin)(xin)肌(ji)(ji)細胞的抗缺血能力(li),從(cong)而可預防心(xin)(xin)臟性猝死的發生。
埋藏式自(zi)動心(xin)臟復律除(chu)顫(zhan)器(ICD)的(de)應(ying)用是防治心(xin)臟性猝(cu)死(si)的(de)重(zhong)要(yao)進展,對致命(ming)性室(shi)性心(xin)律失(shi)常引起的(de)心(xin)臟性猝(cu)死(si)具有(you)肯定(ding)的(de)防治作(zuo)用。
植入ICD的臨(lin)床價(jia)值在于(yu)有效地(di)防治(zhi)心臟(zang)(zang)猝(cu)死。據文(wen)獻報道(dao),美國每年因(yin)心臟(zang)(zang)驟停(ting)而(er)發(fa)(fa)生心臟(zang)(zang)性猝(cu)死的患(huan)者達50萬人(ren)以上(shang),歐洲約40萬人(ren)。其中(zhong)75%~80%的患(huan)者在第1次心臟(zang)(zang)驟停(ting)發(fa)(fa)作(zuo)時死亡(wang),經有效心肺腦復(fu)蘇而(er)幸存者中(zhong)20%~25%的患(huan)者可在1年內再次發(fa)(fa)生心臟(zang)(zang)驟停(ting),因(yin)此,ICD的應(ying)用范圍非常廣泛。
也有一些學者對植(zhi)入ICD的(de)(de)兩種不(bu)同方(fang)式進(jin)行了對比,結(jie)果(guo)發現經靜脈(mo)植(zhi)入ICD的(de)(de)圍(wei)術期病(bing)死(si)率較低,長期隨(sui)訪(fang)(fang)的(de)(de)存活率高,應列為首選方(fang)法。Saksena等總結(jie)了221例多中心植(zhi)入ICD的(de)(de)結(jie)果(guo),開(kai)胸法植(zhi)入ICD的(de)(de)圍(wei)術期病(bing)死(si)率為4.2%,經靜脈(mo)法為0.8%,隨(sui)訪(fang)(fang)2年的(de)(de)總成活率分別為81.9%和87.6%,并無顯著性差異。
為(wei)了明確(que)揭示埋藏(zang)(zang)式心(xin)(xin)(xin)臟(zang)(zang)復(fu)(fu)律(lv)(lv)(lv)除顫(zhan)器防治(zhi)(zhi)心(xin)(xin)(xin)臟(zang)(zang)猝(cu)死(si)的(de)價值,有(you)學者進行了一些(xie)多(duo)(duo)中(zhong)心(xin)(xin)(xin)隨(sui)機化前瞻(zhan)性(xing)對照(zhao)研究(jiu)。抗心(xin)(xin)(xin)律(lv)(lv)(lv)失常(chang)藥物(wu)與埋藏(zang)(zang)式心(xin)(xin)(xin)臟(zang)(zang)復(fu)(fu)律(lv)(lv)(lv)除顫(zhan)器對致命性(xing)室(shi)性(xing)心(xin)(xin)(xin)律(lv)(lv)(lv)失常(chang)復(fu)(fu)蘇患者治(zhi)(zhi)療比(bi)較研究(jiu)(AVID)表明,室(shi)顫(zhan)復(fu)(fu)蘇者或有(you)癥狀和(he)血(xue)流動(dong)力學障礙的(de)持(chi)續性(xing)室(shi)性(xing)心(xin)(xin)(xin)動(dong)過速患者,應用埋藏(zang)(zang)式心(xin)(xin)(xin)臟(zang)(zang)復(fu)(fu)律(lv)(lv)(lv)除顫(zhan)器與抗心(xin)(xin)(xin)律(lv)(lv)(lv)失常(chang)藥物(wu)相比(bi),可明顯提高生存率。其他一些(xie)多(duo)(duo)中(zhong)心(xin)(xin)(xin)試(shi)驗(yan)如多(duo)(duo)中(zhong)心(xin)(xin)(xin)自動(dong)除顫(zhan)器埋藏(zang)(zang)試(shi)驗(yan)(MADIT)、加拿大埋藏(zang)(zang)式除顫(zhan)器研究(jiu)(CIDS)、漢堡心(xin)(xin)(xin)臟(zang)(zang)驟停研究(jiu)(CASH)、美國心(xin)(xin)(xin)、肺和(he)血(xue)液研究(jiu)所埋藏(zang)(zang)式心(xin)(xin)(xin)臟(zang)(zang)復(fu)(fu)律(lv)(lv)(lv)除顫(zhan)器(NHLBHCD)等有(you)的(de)已經完(wan)成,有(you)的(de)正(zheng)在(zai)進行,最(zui)后將(jiang)揭示ICD防治(zhi)(zhi)心(xin)(xin)(xin)臟(zang)(zang)性(xing)猝(cu)死(si)的(de)確(que)切價值。
從心臟性猝死復蘇過來的幸運者在1年內發生致命性心律失常的復發率達25%~30%。已有試驗表明,ICD能有效轉復心臟性猝死患者的復發性心室顫動。Newman等對心臟驟停復蘇過來的幸存者進行了回顧性研究,60例患者植入ICD而120例患者僅僅使用藥物治療,兩組病例的年齡、左心室射血分數、心律失常類型、基礎心臟病和藥物治療情況相似。結果,ICD植入者的心臟性猝死率降低50%(10%∶5%,P<0.01),3年實際病死率降低31%(51%∶35%,P<0.01),5年的生存曲線也有明顯差異。但是,也必須注意,許多心臟性猝死幸存者(20%~70%)最后并不一定死于致命性心律失常,大約5%的心臟性猝死幸存者死于電-機械分離,而ICD對這種類型的心律失常無效。
①經導管射(she)頻消(xiao)融治療(liao)室(shi)(shi)性心(xin)(xin)律失常(chang):室(shi)(shi)性心(xin)(xin)動(dong)過速(su)發(fa)作時常(chang)引(yin)起嚴重的(de)(de)(de)血流動(dong)力(li)學障礙,心(xin)(xin)臟性猝(cu)死的(de)(de)(de)發(fa)生率高。1988年,Davis首次(ci)使(shi)(shi)用(yong)射(she)頻消(xiao)融治療(liao)室(shi)(shi)性心(xin)(xin)動(dong)過速(su)成功(gong),開創射(she)頻消(xiao)融的(de)(de)(de)新領域,但至今(jin)仍不如室(shi)(shi)上性心(xin)(xin)動(dong)過速(su)使(shi)(shi)用(yong)普遍。室(shi)(shi)性心(xin)(xin)動(dong)過速(su)的(de)(de)(de)消(xiao)融,成功(gong)的(de)(de)(de)關(guan)鍵之一是心(xin)(xin)動(dong)過速(su)的(de)(de)(de)起源定位(wei),其方(fang)法是進(jin)行心(xin)(xin)內膜(mo)標測(ce)(ce),一般(ban)根據Josephson提出的(de)(de)(de)18個點(dian)標測(ce)(ce),左心(xin)(xin)室(shi)(shi)12,右心(xin)(xin)室(shi)(shi)6個,標測(ce)(ce)方(fang)法有(you)3種:
A.竇性(xing)心律時的標測:
在竇性心律下,在心室的不同部位尋找有明顯延遲碎裂電位的部位。延遲破裂電位是缺血區殘存心肌纖維的非同步除極,常常被大量結締組織所包繞,彼此連接較少,因此傳導很慢,形成緩慢傳導區,成為室性心動過速折返環的重要組成部分。在低倍放大條件下,延遲碎裂電位表現為高頻成分組成的低振幅波(<1mV),持續100ms以上。但必須注意,延遲破裂電位僅僅表示該部位有傳導延緩。并不表示一定為室性心動過速的起源部位,因此,竇性心律下的標測是不可靠的。
B.起搏標測:
用電(dian)極在(zai)心(xin)(xin)(xin)室(shi)的(de)不(bu)同(tong)部位(wei)作(zuo)心(xin)(xin)(xin)內膜起(qi)(qi)搏(bo)(bo),起(qi)(qi)搏(bo)(bo)頻率與(yu)(yu)心(xin)(xin)(xin)動過(guo)速的(de)頻率相(xiang)同(tong),記錄12導(dao)聯心(xin)(xin)(xin)電(dian)圖,若11個以上導(dao)聯的(de)圖形與(yu)(yu)心(xin)(xin)(xin)動過(guo)速發作(zuo)時的(de)相(xiang)同(tong),可(ke)認(ren)為該起(qi)(qi)搏(bo)(bo)部位(wei)即是心(xin)(xin)(xin)動過(guo)速的(de)起(qi)(qi)源(yuan)部位(wei),但起(qi)(qi)搏(bo)(bo)標測也(ye)不(bu)可(ke)靠。
C.心動過速時的標測:
有心(xin)動過速(su)(su)發作時,在心(xin)室(shi)內不同(tong)部位(wei)(wei)記錄心(xin)內膜電圖,比較(jiao)(jiao)哪一部位(wei)(wei)的(de)(de)心(xin)室(shi)激動時間比體表心(xin)電圖的(de)(de)QRS波提前,則最早激動的(de)(de)部位(wei)(wei)是心(xin)動過速(su)(su)的(de)(de)起源點。心(xin)運過速(su)(su)的(de)(de)標測是室(shi)性心(xin)動過速(su)(su)定位(wei)(wei)的(de)(de)較(jiao)(jiao)可靠(kao)方法。
準確(que)定(ding)位(wei)后,行射頻消(xiao)融,一般用(yong)30~40W,10~30s。成功(gong)的(de)因素是(shi):精確(que)的(de)起(qi)(qi)搏(bo)標測;最(zui)早的(de)局部(bu)心(xin)(xin)(xin)(xin)室(shi)(shi)激(ji)動;導管電(dian)極與心(xin)(xin)(xin)(xin)內膜(mo)密(mi)(mi)切接(jie)觸(chu)。失敗的(de)因素是(shi):消(xiao)融電(dian)極未(wei)到達(da)起(qi)(qi)源點;導管電(dian)極與心(xin)(xin)(xin)(xin)內膜(mo)接(jie)觸(chu)不(bu)緊密(mi)(mi);室(shi)(shi)性(xing)心(xin)(xin)(xin)(xin)動過速的(de)起(qi)(qi)源點位(wei)于心(xin)(xin)(xin)(xin)肌內或心(xin)(xin)(xin)(xin)外膜(mo)。
不(bu)同類型的(de)(de)室(shi)速,消(xiao)融的(de)(de)療效不(bu)同,其中(zhong),無器質心(xin)(xin)(xin)臟病的(de)(de)特(te)發性室(shi)速,成(cheng)(cheng)功(gong)(gong)率達94%。束支折(zhe)返性心(xin)(xin)(xin)動過(guo)速,是(shi)由(you)希(xi)氏-心(xin)(xin)(xin)肌(ji)傳導系(xi)統參與的(de)(de)大折(zhe)返,消(xiao)融右(you)束即可(ke)終止室(shi)速,成(cheng)(cheng)功(gong)(gong)率超過(guo)90%。目前(qian)較困難的(de)(de)是(shi)梗死后(hou)室(shi)性心(xin)(xin)(xin)動過(guo)速成(cheng)(cheng)功(gong)(gong)率不(bu)高,一(yi)般(ban)在(zai)45%~93%,差異較大,其原因在(zai)于梗死性心(xin)(xin)(xin)動過(guo)速的(de)(de)機制較復雜所(suo)致。梗死后(hou)室(shi)性心(xin)(xin)(xin)動過(guo)速的(de)(de)射(she)頻(pin)(pin)消(xiao)融,包(bao)括以下幾種情形:a.瘢(ban)痕周圍折(zhe)返:必須在(zai)瘢(ban)痕組織(zhi)周圍產(chan)生較大損傷,折(zhe)返才能(neng)終止;b.瘢(ban)痕內折(zhe)返:大部分病例可(ke)用射(she)頻(pin)(pin)消(xiao)融成(cheng)(cheng)功(gong)(gong);c.功(gong)(gong)能(neng)性折(zhe)返:射(she)頻(pin)(pin)消(xiao)融常常無效。有(you)時(shi),射(she)頻(pin)(pin)消(xiao)融術后(hou)可(ke)在(zai)功(gong)(gong)能(neng)性上折(zhe)返的(de)(de)基(ji)礎上,增加一(yi)個解剖性因素(su)而(er)產(chan)生更(geng)為頑(wan)固的(de)(de)折(zhe)返性心(xin)(xin)(xin)律失(shi)常。
②經皮球囊冠狀動脈成形(xing)術治(zhi)療冠心病。從理(li)論上(shang)講,經皮球囊冠狀動脈形(xing)成術治(zhi)療冠心病應能有效(xiao)降低心臟(zang)性(xing)猝死的發生率。當迄(qi)今未見到(dao)多中(zhong)心隨機臨床觀察資料。
①室性心律失常的外(wai)科治(zhi)療:
近10幾年來(lai),用手(shou)術切(qie)割、冷凍或(huo)(huo)激光等手(shou)段(duan)可成功地控(kong)制或(huo)(huo)根(gen)治室性(xing)心(xin)動過速/或(huo)(huo)心(xin)室顫動,從而減少心(xin)臟性(xing)猝死的(de)發生(sheng)率(lv)。
A.內膜病灶切(qie)除術:
這種(zhong)治(zhi)療方(fang)法于(yu)(yu)1979年由Harken用于(yu)(yu)臨床,其(qi)方(fang)法是首先進行病(bing)灶定位(wei)(wei)。Harken等的(de)(de)方(fang)法是在常溫體外循環下,用手(shou)持(chi)移動(dong)(dong)(dong)電(dian)極(ji)在心內膜面進行標測,找出最(zui)(zui)早心室(shi)激動(dong)(dong)(dong)部(bu)位(wei)(wei),經左心室(shi)切口對(dui)標測出來的(de)(de)最(zui)(zui)早心室(shi)激動(dong)(dong)(dong)部(bu)位(wei)(wei)作直徑2~3cm厚約數(shu)毫米的(de)(de)盤(pan)狀切除。心內膜病(bing)灶切除術適(shi)用于(yu)(yu)病(bing)灶局(ju)限,尤其(qi)適(shi)用于(yu)(yu)位(wei)(wei)于(yu)(yu)室(shi)壁瘤邊緣而遠離心臟(zang)傳導系統和乳頭肌的(de)(de)病(bing)灶。
B.心內膜環(huan)形(xing)心室肌切(qie)除術:
對于有室(shi)壁瘤而伴發(fa)室(shi)性心(xin)(xin)動過(guo)速的患者可在室(shi)壁瘤邊緣的正常心(xin)(xin)內(nei)膜作弧形切口,深達心(xin)(xin)肌層(ceng)(ceng),直到僅留一層(ceng)(ceng)靠近(jin)心(xin)(xin)外膜的肌橋。該法(fa)由Guiraudon等(deng)于1987年(nian)首創。因(yin)術后左室(shi)受損,現已(yi)少用。
C.心室隔離(li)術:
僅(jin)適用于右(you)心室(shi)(shi)(shi)游離壁(bi)或右(you)心室(shi)(shi)(shi)流出道的病灶(zao)。其方法是以右(you)房溝為基底,圍(wei)繞某一分(fen)支血管對可疑心室(shi)(shi)(shi)壁(bi)做半島狀切開,使它和右(you)心室(shi)(shi)(shi)壁(bi)的其余部分(fen)分(fen)離。
D.外科冷凍消融術(shu):
對于靠近心臟傳導(dao)系統(tong)或(huo)腱索的病(bing)灶,直接進(jin)行(xing)(xing)外科手術切除術可發(fa)(fa)生(sheng)嚴重(zhong)的并發(fa)(fa)癥,則宜(yi)在(zai)外科手術直視下進(jin)行(xing)(xing)冷凍治療(liao),使(shi)病(bing)灶降(jiang)溫至0℃持續1min。如果(guo)有效則降(jiang)溫至-60℃持續2min。
E.外科激光消融術:
用激(ji)光代(dai)替冷(leng)凍而(er)消除心(xin)律(lv)失常的病灶。
②冠狀動脈旁路術:
對于嚴重(zhong)冠(guan)(guan)(guan)狀(zhuang)動(dong)脈病(bing)變(bian)的(de)患者進行冠(guan)(guan)(guan)狀(zhuang)動(dong)脈旁路術可有效(xiao)的(de)改善(shan)心肌供血,減輕或消除心絞(jiao)痛(tong)的(de)癥(zheng)狀(zhuang)。已有一些多(duo)中心研究結果顯示,冠(guan)(guan)(guan)狀(zhuang)動(dong)脈旁路術可延長冠(guan)(guan)(guan)心病(bing)患者的(de)生存(cun)期,但對心臟性(xing)猝(cu)死發(fa)生率的(de)影響(xiang),所見(jian)報道(dao)極少。
(1)判斷意識
拍雙(shuang)肩,喚雙(shuang)耳(er),搭脈搏,10秒(miao)鐘(zhong)內完成
(2)呼(hu)救(撥(bo)打120)
完成第一步后,馬上(shang)拔打120,給(gei)病人(ren)爭取救治的(de)第一時間。
(3)擺放仰臥(wo)體(ti)位
(4)胸外按(an)壓30次(ci)(兒童15次(ci))
位置:胸部正(zheng)中,兩(liang)乳頭連線中點;
姿勢:肩(jian)關節(jie)、肘關節(jie)、腕關節(jie)垂直成一條直線。
雙手(shou)掌重疊,手(shou)指(zhi)抬起;掌根用力。
力(li)度:按下去至(zhi)少5cm;
頻率:至少100次(ci)/分鐘;
(5)開放(fang)氣道(仰(yang)頭舉頦法)
(6)人工吹(chui)氣2次(ci)(兒童(tong)1次(ci))捏鼻,口包口,吹(chui)氣
(7)重復第四、五(wu)、六步
(8)注意事項:研究(jiu)發(fa)(fa)現(xian),倒地1分鐘(zhong)(zhong)內進行心肺(fei)復蘇,救活的概率為(wei)90%;2分鐘(zhong)(zhong)內60%;4分鐘(zhong)(zhong)內40%;8分鐘(zhong)(zhong)內為(wei)20%;超過10分鐘(zhong)(zhong),基本上就是零(ling)了。為(wei)了預防心源性(xing)猝死,中、老年(nian)人和肥(fei)胖者(zhe)、糖尿病(bing)(bing)者(zhe)、應定期(qi)到醫院檢查,發(fa)(fa)現(xian)潛在性(xing)心血管(guan)病(bing)(bing)就及時治療,并應防止各種誘發(fa)(fa)因(yin)素。
飲食適宜
建(jian)議適當(dang)限制辛(xin)辣生冷刺激性(xing)食(shi)物(wu)。缺(que)血(xue)性(xing)心臟病常伴(ban)有高血(xue)壓高血(xue)脂糖尿病,如(ru)果(guo)你同(tong)時伴(ban)有以(yi)上疾(ji)病,可針對給予低鹽(yan)低脂低糖飲食(shi)。
建議平時飲食(shi)(shi)清淡,不可集中食(shi)(shi)用過多(duo)蔬菜(cai)或高脂(zhi)食(shi)(shi)物(wu),低鹽低脂(zhi)飲食(shi)(shi),少吃動物(wu)的內臟,多(duo)喝水,避免辛(xin)辣和生冷(leng),戒煙酒,適(shi)當運動鍛煉,保(bao)持樂觀舒(shu)暢的心情,保(bao)持良(liang)好(hao)的睡眠,不要長時間熬夜,放松精神,心態(tai)平和。
飲食禁忌
紅(hong)肉:這些肉類含有大(da)量阻塞(sai)動脈的飽和脂(zhi)肪,不利于心臟健康。
汽(qi)水:汽(qi)水含有大量(liang)單糖和(he)熱量(liang),是引起兒童(tong)和(he)成人肥胖的食品之一。
薯條:薯條含有飽和脂(zhi)(zhi)肪和轉(zhuan)脂(zhi)(zhi)肪,會引(yin)起(qi)人們肥胖(pang),增加心臟病風險。
(1)定(ding)期體檢(jian):老年人本身(shen)是心(xin)臟病(bing)(bing)及(ji)各種(zhong)疾病(bing)(bing)的(de)高發人群,應定(ding)期到醫院進行(xing)體檢(jian)。青、中年人工(gong)作緊張、生活節(jie)奏(zou)快、工(gong)作生活壓力大也容易(yi)患冠心(xin)病(bing)(bing)、高血壓等疾病(bing)(bing)。定(ding)期體檢(jian)及(ji)早(zao)(zao)檢(jian)查便于及(ji)時發現(xian)疾病(bing)(bing),及(ji)早(zao)(zao)進行(xing)治療,減少猝死風險。
(2)避免過(guo)度(du)疲(pi)(pi)勞(lao)和(he)精神(shen)緊張:過(guo)度(du)疲(pi)(pi)勞(lao)和(he)精神(shen)緊張會(hui)使(shi)機體處(chu)于應(ying)激狀(zhuang)態,使(shi)血壓升高,心臟負(fu)擔加重,使(shi)原有(you)心臟病加重。即(ji)使(shi)原來沒有(you)器質性心臟病也會(hui)引(yin)發(fa)室顫的(de)發(fa)生。所以,每個(ge)人(ren)應(ying)該對自己(ji)的(de)工作(zuo)、生活有(you)所安排,控制工作(zuo)節奏(zou)和(he)工作(zuo)時間(jian),不可過(guo)快過(guo)長。
(3)戒煙、限酒、平衡膳食、控制體重(zhong)、適當運動,保持良好的生活(huo)習慣會減少心腦血(xue)管疾(ji)病的發生。
(4)注意過度(du)疲勞的(de)危險信(xin)號及重視(shi)發(fa)病(bing)的(de)前(qian)兆癥狀:長期(qi)過度(du)疲勞會引發(fa)身體出現一(yi)些(xie)改(gai)變。如焦慮易(yi)怒(nu)、記憶力減(jian)退、注意力不(bu)集中、失眠(mian)及睡(shui)眠(mian)質量差(cha)、頭痛頭暈耳鳴、性功(gong)能(neng)(neng)減(jian)退、脫發(fa)明顯等。當(dang)機(ji)體出現這(zhe)些(xie)情況,應(ying)調(diao)整(zheng)工作(zuo)節奏、適當(dang)休息,調(diao)整(zheng)節奏,保持愉快的(de)心情。讓機(ji)體功(gong)能(neng)(neng)得以(yi)恢(hui)復。如不(bu)能(neng)(neng)緩解,應(ying)立(li)即(ji)前(qian)往醫院救治。
(5)對已患(huan)有冠心病、高血壓等疾病的(de)患(huan)者應(ying)在醫生指導下堅持(chi)服藥治療。
(6)注意對室性心(xin)律失(shi)常進行(xing)危險評(ping)(ping)估(gu),包(bao)括進行(xing)常規心(xin)電(dian)圖、動態(tai)心(xin)電(dian)圖、其他心(xin)電(dian)學技(ji)術、超聲心(xin)動圖、心(xin)內(nei)電(dian)生理檢查(cha)等檢查(cha),以明確心(xin)律失(shi)常類(lei)型,評(ping)(ping)估(gu)心(xin)臟猝死風險,做(zuo)出治療(liao)決策。
(7)注意加強(qiang)心(xin)梗后(hou)心(xin)臟猝(cu)死的預防。