Clinical significance of residual ischaemia in acute myocardial infarction complicated by cardiogenic shock...

Area of Science:

• Cardiology
• Interventional Cardiology
• Critical Care Medicine

Background:

• Acute myocardial infarction (AMI) with cardiogenic shock (CS) is a critical condition often requiring mechanical circulatory support.
• Venoarterial-extracorporeal membrane oxygenation (VA-ECMO) is used for refractory CS, but outcomes remain challenging.
• The impact of residual ischemia after revascularization in AMI patients on VA-ECMO is not well-defined.

Purpose of the Study:

• To evaluate the effect of residual ischemia on clinical outcomes in patients with AMI undergoing VA-ECMO.
• To determine if the degree of residual ischemia, quantified by residual SYNTAX score (rSS), impacts 1-year all-cause mortality.

Main Methods:

• Retrospective analysis of pooled data from the RESCUE and SMC-ECMO registries.
• Patients with AMI, multivessel disease, and refractory CS treated with VA-ECMO were categorized by residual SYNTAX score (rSS): rSS = 0, 0 < rSS ≤ 8, and rSS > 8.
• 1-year all-cause death was the primary outcome, analyzed using multivariable models.

Main Results:

• A total of 408 patients were included: rSS = 0 (24.5%), 0 < rSS ≤ 8 (33.3%), and rSS > 8 (42.2%).
• 1-year mortality was significantly higher with increasing rSS (33.9% vs. 55.4% vs. 66.1%, P < 0.001).
• Residual ischemia (rSS) was an independent predictor of 1-year mortality (aHR 1.03, P = 0.003), while baseline SYNTAX score was not.

Conclusions:

• Residual ischemia in AMI patients with refractory CS supported by VA-ECMO is associated with increased 1-year mortality.
• Strategies to minimize residual ischemia in this patient population warrant further investigation.
• Future research should focus on revascularization efficacy and safety to improve outcomes in VA-ECMO patients.