# Correlation Between Ischemia Time and Left Ventricular Failure After Primary Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction (STEMI) Patients

## TL;DR

This study shows that longer ischemia time and other factors like diabetes and age increase the risk of heart failure after a heart attack treatment called PPCI.

## Contribution

The study identifies ischemia duration and comorbidities as key predictors of left ventricular failure after PPCI in STEMI patients.

## Key findings

- Prolonged ischemia time significantly increases the risk of severe left ventricular dysfunction.
- Diabetes, hypertension, and previous cardiac events are strong predictors of left ventricular failure.
- 20.33% of patients developed LVF during the six-month follow-up period.

## Abstract

Background: Primary percutaneous coronary intervention (PPCI) is pivotal in treating ST-elevation myocardial infarction (STEMI) patients, yet ischemia time significantly impacts outcomes, particularly left ventricular failure (LVF).

Objective: This study aimed to investigate the impact of ischemia duration and other variables associated with severe left ventricular systolic dysfunction in STEMI patients receiving PPCI treatment.

Methodology: This prospective cohort was carried out at Lady Reading Hospital in Peshawar, Pakistan, from January to June 2023. The study included 236 patients aged 18 to 70 with acute myocardial infarction who underwent PPCI within 12 hours of symptom onset. Patients with coronary dissection, late presenters (more than 12 hours after onset), those without stenting, and those with prior coronary artery intervention were excluded. Additionally, patients with systolic heart failure, a history of arrhythmias such as ventricular tachycardia or ventricular fibrillation, or a previous acute coronary syndrome event were excluded. Demographic information, clinical background, and ischemia duration were recorded and associated with left ventricular ejection fraction (LVEF) after PPCI. To identify predictors of severe left ventricular dysfunction, statistical analysis using SPSS Statistics version 26.0 (IBM Corp. Released 2019. IBM SPSS Statistics for Windows, Version 26.0. Armonk, NY: IBM Corp.) included multivariate regression, Pearson's correlation, and descriptive statistics.

Results: The patients' average age was 61.2 years (SD ± 12.3), with 35.59% of them being female (84 patients) and 64.41% of them being male (152 patients). Diabetes (33.05%, 78 patients) and hypertension (43.22%, 102 patients) were common comorbidities, and 14.41% (34 patients) had previously had a cardiac episode. Fifty-two patients (22.03%) of the total had ischemia within three hours, 94 patients (39.83%) had ischemia within six hours, 60 patients (25.42%) had ischemia within nine hours, and 30 patients (12.71%) had ischemia within 12 hours. Analysis of LVEF showed that 9.32% of patients (n=22) had LVEF <30% and 24.58% of patients (n=58) had LVEF 30-40%. Significant predictors of severe left ventricular systolic dysfunction were shown by multivariate regression to include ischemia duration (OR 1.45, p<0.001), age (OR 1.02, p=0.015), diabetes (OR 2.34, p=0.001), hypertension (OR 1.76, p=0.031), and previous cardiac events (OR 2.89, p=0.002); 20.33% of the patients (n=48) had LVF during the six-month follow-up, highlighting the therapeutic significance of prompt management in STEMI patients after PPCI.

Conclusion: Prolonged ischemia, advanced age, diabetes, hypertension, and previous cardiac events that predict severe left ventricular dysfunction are associated with a greater risk of LVF following PPCI. Timely intervention and thorough therapy are essential for enhancing results for STEMI patients at high risk.