Incidence and Risk Factors for Ventricular Arrhythmias in Patients With Acute Myocardial Infarction Presenting to the Emergency Department.

BACKGROUND

Ventricular arrhythmias remain one of the most serious complications of acute myocardial infarction (AMI), often leading to hemodynamic instability and sudden cardiac death.

OBJECTIVES

The study aimed to determine the incidence of ventricular arrhythmias in AMI patients presenting to the emergency department, identify associated risk factors, and assess their impact on in-hospital outcomes.

METHODOLOGY: This cross-sectional analytical study was conducted at Shaikh Zayed Hospital, Lahore, Pakistan, from March 2024 to September 2024, and included 196 patients diagnosed with AMI. Clinical, demographic, laboratory, and echocardiographic data were recorded. Patients were continuously monitored using ECG during their stay in the emergency department and subsequently throughout hospitalization for up to eight days to detect ventricular arrhythmias, defined as ventricular tachycardia or ventricular fibrillation.

RESULTS

Ventricular arrhythmias were observed in 58 patients (29.6%), including ventricular tachycardia in 19.9% and ventricular fibrillation in 9.7%. Most events (70.7%) occurred within the first 48 hours. Significant predictors included age > 60 years (adjusted odds ratio (AOR) = 1.9), hypertension (AOR = 2.0), diabetes mellitus (AOR = 2.1), anterior wall infarction (AOR = 2.3), Killip class ≥ II (AOR = 2.8), and delayed hospital arrival > 6 hours (AOR = 2.5). Patients with arrhythmias had longer hospital stays (6.2 ± 2.1 vs. 4.8 ± 1.7 days, p = 0.001) and higher in-hospital mortality (20.7% vs. 5.8%, p = 0.001).

CONCLUSIONS

Ventricular arrhythmias occurred in nearly one-third of AMI patients, predominantly within the first 48 hours, and were associated with significantly worse in-hospital outcomes. Continuous ECG monitoring during the emergency phase and throughout hospitalization is essential for early detection. The risk factors for ventricular arrhythmias included hypertension, diabetes mellitus, age above 60 years, delayed hospital arrival beyond six hours, low serum potassium, low serum magnesium, and anterior wall infarction.