Background
Recent studies increasingly point to the significance of mechanical circulatory support (MCS) devices in treating refractory cardiogenic shock (CS) due to an acute myocardial infarction (AMI). Nevertheless, there is a notable absence of large, randomized trials focusing on the direct head-to-head comparison of Impella and extracorporeal veno-arterial membrane oxygenation (VA-ECMO) in managing AMI-related CS. Consequently, evidence from thorough retrospective studies or meta-analyses plays a crucial role in clarifying the utility of these devices in such circumstances.
Method
This meta-analysis included only clinical trials focusing on patients treated with Impella or VA-ECMO for managing CS resulting from an AMI, aiming to a crude head-to-head comparison of these devices in the setting of AMI-mediated CS (Figure 1). The main outcome evaluated was the 30-day mortality rate, with secondary outcomes including major bleeding and ischemic vascular complications.
Results
Ten studies comprising a total of 3,949 patients were included in the present meta-analysis. Left ventricular function was upon LCS initiation was similar between the 2 groups (Figure 2). Impella showed a statistically significant lower 30-day mortality rate compared to VA-ECMO (0.91, Confidence Interval (CI) 0.84 to 0.99) (Figure 3). Moreover, vascular complications (0.41, CI 0.31 to 0.57 Figure 4) and major bleeding events (0.67, CI 0.49 to 0.93 Figure 5) were also significantly lower in the Impella-group.
Conclusion
This meta-analysis suggests that Impella may be associated with a lower mortality compared to VA-ECMO in AMI-mediated CS, mainly due to less vascular complications and bleeding events. Though not evident, our data may suggest a possible mode of escalation therapy in the setting of AMI-associated CS.
