Division of Cardiology, Triemli Hospital Zurich, Switzerland.
Institute of Primary Care, University of Zurich, Switzerland.
Eur Heart J Acute Cardiovasc Care. 2020 Dec;9(8):848-856. doi: 10.1177/2048872620905101. Epub 2020 Feb 7.
In patients with acute myocardial infarction, the presence of a left bundle branch block or right bundle branch block may be associated with worse prognosis compared to isolated ST segment elevation. However, specificities in clinical presentation and outcomes of acute myocardial infarction patients with left bundle branch block or right bundle branch block are poorly characterized.
We analysed acute myocardial infarction patients with left bundle branch block (=880), right bundle branch block (=732) or ST segment elevation without bundle branch block (=15,852) included in the Acute Myocardial Infarction in Switzerland-Plus registry between 2008-2019.
Acute myocardial infarction patients with bundle branch block were older and had more pre-existing cardiovascular conditions compared to ST segment elevation. Pulmonary oedema and cardiogenic shock were most frequent in patients with left bundle branch block (18.8% vs 12.0% for right bundle branch block and 7.9% for ST segment elevation, <0.001). Acute myocardial infarction patients with bundle branch block had more three-vessel (40.6% vs 25.3%, <0.001 vs ST segment elevation) and left main disease (5.6% vs 2.0%, <0.001 vs ST segment elevation). Major adverse cardiac and cerebrovascular events, a composite of reinfarction, stroke/transient ischaemic attack, and death during hospitalization, were highest in acute myocardial infarction patients with left bundle branch block (13.9% vs 9.9% for right bundle branch block and 6.7% for ST segment elevation, <0.05), which was driven by hospital mortality. After multivariate adjustment, however, mortality was similar in patients with left bundle branch block and lower in patients with right bundle branch block, respectively, when compared to ST segment elevation. Mortality was only increased when a right bundle branch block with concomitant STE was present (odds ratio 1.77, 95% confidence interval 1.19-2.64, <0.01 vs ST segment elevation).
Compared to ST segment elevation, an isolated bundle branch block reflects high-risk clinical characteristics but does not independently determine increased hospital mortality in acute myocardial infarction.
在急性心肌梗死患者中，左束支传导阻滞或右束支传导阻滞的存在可能比孤立的 ST 段抬高与更差的预后相关。然而，左束支传导阻滞或右束支传导阻滞的急性心肌梗死患者的临床表现和结局的特异性特征描述较差。
我们分析了 2008 年至 2019 年期间瑞士急性心肌梗死注册研究中纳入的急性心肌梗死患者（伴左束支传导阻滞=880 例，伴右束支传导阻滞=732 例，无束支传导阻滞伴 ST 段抬高=15852 例）。
与 ST 段抬高相比，伴有束支传导阻滞的急性心肌梗死患者年龄较大，且存在更多的心血管疾病既往史。左束支传导阻滞患者中肺水肿和心源性休克最为常见（18.8%比右束支传导阻滞的 12.0%和 ST 段抬高的 7.9%，<0.001）。伴有束支传导阻滞的急性心肌梗死患者中三支血管病变（40.6%比 25.3%，<0.001比 ST 段抬高）和左主干病变（5.6%比 2.0%，<0.001比 ST 段抬高）更为常见。主要不良心脏和脑血管事件（再梗死、卒中和短暂性脑缺血发作、住院期间死亡的复合事件）在左束支传导阻滞患者中最高（13.9%比右束支传导阻滞的 9.9%和 ST 段抬高的 6.7%，<0.05），这主要是由住院死亡率导致的。然而，经过多变量调整后，与 ST 段抬高相比，左束支传导阻滞患者的死亡率相似，而右束支传导阻滞患者的死亡率则较低。只有当右束支传导阻滞伴有同步 ST 段抬高时，死亡率才会增加（比值比 1.77，95%置信区间 1.19-2.64，<0.01 比 ST 段抬高）。
与 ST 段抬高相比，孤立性束支传导阻滞反映了高风险的临床特征，但不能独立决定急性心肌梗死患者住院死亡率的增加。
