Association of Left Ventricular Size on Outcomes in Patients With Left Main Coronary Artery Myocardial Infarction Complicated by Cardiogenic Shock

ABSTRACT Background Cardiogenic shock in left main coronary artery acute myocardial infarction patients has high mortality rates. This study investigates the association between left ventricular size and outcomes in these patients treated with veno‐arterial extracorporeal membrane oxygenation. Methods This retrospective single‐center study examined patients who underwent percutaneous coronary intervention for left main coronary artery acute myocardial infarction and developed refractory cardiogenic shock between April 2013 and August 2021. Baseline characteristics and echocardiographic assessments were conducted 24–48 h after veno‐arterial extracorporeal membrane oxygenation initiation. Patients were divided into two groups: small left ventricle (S‐group, ≤ 23 mm/m 2 for males and ≤ 26 mm/m 2 for females, n  = 11) and regular left ventricle (R‐group, n  = 22). The primary outcome was a 1‐year survival. The analysis included survival and adjusted multivariate Cox proportional hazards modeling. Results The S‐group showed a significantly higher mortality rate during support (63.6% vs. 4.5%, p  = 0.001). In the unadjusted survival analysis, the 1‐year survival rate was significantly lower in the S‐group (9.0% [95% CI, 1.4–58.9] vs. 59.1% [95% CI, 41.7–83.6], p  < 0.01). After adjusting for confounders, multivariate Cox analysis identified a small left ventricle (adjusted HR 8.38, 95% CI 2.33–30.16, p  = 0.001), advanced age (per 10‐year increase, adjusted HR 2.35, 95% CI 1.39–3.98, p  = 0.001), and lower baseline left ventricular ejection fraction (per 10% decrease, adjusted HR 0.48, 95% CI 0.26–0.88, p  = 0.018) as significant predictors of 1‐year all‐cause mortality. Conclusions In patients with severe cardiogenic shock following left main coronary artery acute myocardial infarction requiring veno‐arterial extracorporeal membrane oxygenation, a small left ventricle is associated with a poor prognosis.