RESUMO
Background Acute myocardial infarction (AMI) is a leading cause of morbidity and mortality worldwide, particularly in low- and middle-income countries like Pakistan, where healthcare resources are limited. Early Invasive Strategy (EIS), typically involving percutaneous coronary intervention (PCI), has been shown to improve outcomes in AMI patients. However, the effectiveness of EIS in resource-limited settings, such as Pakistan, remains under-explored. Objective This prospective observational cohort study aimed to assess the impact of an Early Invasive Strategy (EIS) on left ventricular (LV) function recovery in acute myocardial infarction (AMI) patients in Pakistan. The primary objective was to measure the change in left ventricular ejection fraction (LVEF) over six months. Secondary objectives included evaluating mortality, rehospitalization rates, and incidences of major adverse cardiovascular events (MACE). Multivariate regression analysis was employed to adjust for potential confounders. Methods The study was conducted from January to December 2023 at the National Institute of Cardiovascular Diseases (NICVD) satellite centers in Sukkur, Nawab Shah, and Khairpur. A total of 300 AMI patients presenting within 24 hours of symptom onset were included. Participants were divided into two groups: the EIS group (n = 150) received percutaneous coronary intervention (PCI) within 24 hours of admission, while the delayed treatment group (n = 150) received standard therapy, with invasive procedures performed after 24 hours if clinically indicated. Data were collected at baseline, during hospitalization, and at three- and six-months post-AMI. Results The EIS group demonstrated a significantly greater improvement in LVEF compared to the delayed treatment group (13.1% [95% CI, 10.8%-15.4%] vs. 7.5% [95% CI, 5.8%-9.2%], p < 0.001). Mortality was lower in the EIS group (3% [n = 4] vs. 9% [n = 13], p = 0.01), as were rehospitalizations for heart failure (7% [n = 10] vs. 14% [n = 21], p = 0.02) and incidences of MACE (8% [n = 12] vs. 16% [n = 24], p = 0.01). Multivariate regression analysis confirmed that EIS was independently associated with better LVEF improvement (coefficient = 5.78 [95% CI, 4.21-7.35], p < 0.001). Conclusion Early invasive treatments significantly enhance left ventricular function recovery and reduce mortality and rehospitalization rates in AMI patients in Pakistan. These findings advocate for the implementation of timely PCI interventions in resource-limited settings to improve clinical outcomes, particularly emphasizing cost-effectiveness and the availability of PCI.