Prevalence and prognostic implications of reduced left ventricular ejection fraction among patients with STEMI in India.

Aims: To describe clinical characteristics and outcomes for those with STEMI and reduced left ventricular ejection fraction (LVEF) in low-income and middle-income countries (LMICs).

Methods And Results: Adults presenting with STEMI to two government-owned tertiary care centres in Delhi, India were prospectively enrolled in the North India ST-elevation myocardial infarction (NORIN-STEMI) registry. LVEF was evaluated at presentation and clinical characteristics were compared across LVEF categories. Overall, 3597 patients were included, of whom 468 (13%) had LVEF >50%, 1482 (41%) had mildly reduced LVEF (40-49%), 1357 (38%) had moderately reduced LVEF (30-39%), and 290 (8%) had severely reduced LVEF (<30%). Presentation delay >24 h, prior MI, and hyperlipidaemia were associated with decreasing LVEF category. Although most patients with reduced LVEF were discharged on appropriate guideline-directed therapies, adherence at 1 year was low (ACE inhibitor/ARB 91% to 41%, beta blocker 98% to 78%, aldosterone receptor antagonist 69% to 6%). After multivariable adjustment, a Cox regression model showed moderately reduced LVEF (HR 1.77, 95% CI 1.20, 2.60) and severely reduced LVEF (HR 3.63, 95% CI 2.41, 5.48) were associated with increased risk of all-cause mortality compared with LVEF ≥50%.

Conclusions: On presentation for STEMI, almost 90% of NORIN-STEMI participants had at least mildly reduced LVEF and almost half had LVEF <40%. Patients with LVEF <40% had significantly higher risk of mortality at 1 year, and adherence to guideline-directed therapies at 1 year was poor. Systematic initiatives to improve access to timely revascularization and guideline-directed therapies are essential in advancing STEMI care in LMICs.