Background:Patients with anterior acute myocardial infarction (AMI) and left ventricular (LV) dysfunction have an increased risk of LV thrombus (LVT). In the thrombolytic era, short-term anticoagulation using low-molecular-weight heparin during hospitalization proved to significantly reduce LVT formation, but, the effect of this prophylactic approach remains unclear in the current era. Therefore, we conducted a study to evaluate the effects of post-procedural anticoagulation (PPAC) using enoxaparin in addition to dual antiplatelet therapy (DAPT) after primary percutaneous coronary intervention (PCI) in such patients.

Methods and Results:A total of 426 anterior AMI patients with LV ejection fraction ≤40% were retrospectively enrolled and classified into 2 groups based on whether they received PPAC (enoxaparin SC for at least 7 days). All patients received primary PCI and DAPT. The primary endpoint was definite LVT at 30 days diagnosed by echocardiography. The secondary endpoints were 30-day mortality, embolic events, and major bleeding events. PPAC was independently associated with a lower incidence of LVT (odds ratio 0.139, 95% confidence interval 0.032−0.606, P=0.009). The 30-day mortality, embolic events, and major bleeding events were not statistically different between groups.

Conclusions:Short-term PPAC using enoxaparin after primary PCI may be an effective and safe way to prevent LVT in patients with anterior AMI and LV dysfunction.

背景：患有急性急性心肌梗死（AMI）和左心室（LV）功能障碍的患者发生LV血栓（LVT）的风险增加。在溶栓时代，住院期间使用低分子量肝素进行短期抗凝治疗可显着减少LVT的形成，但在当前时代，这种预防方法的效果尚不清楚。因此，我们进行了一项研究，以评估在此类患者的原发性经皮冠状动脉介入治疗（PCI）后，除了使用双重抗血小板治疗（DAPT）以外，还使用依诺肝素进行了术后抗凝（PPAC）的效果。

方法与结果：回顾性分析426例左室射血分数≤40％的前AMI患者，根据是否接受PPAC（依诺肝素SC治疗至少7天）分为两组。所有患者均接受了原发性PCI和DAPT。主要终点是通过超声心动图诊断的30天时明确的LVT。次要终点为30天死亡率，栓塞事件和重大出血事件。PPAC与较低的LVT发生率独立相关（赔率0.139，95％置信区间0.032-0.606，P = 0.009）。两组之间的30天死亡率，栓塞事件和主要出血事件在统计学上没有差异。

结论：在原发性PCI后短期使用依诺肝素的PPAC可能是预防AMI和LV功能障碍的LVT的一种安全有效的方法。