The PR Interval Predicted Major Adverse Cardiovascular Events in Patients with Acute Coronary Syndrome Who Underwent Percutaneous Coronary Intervention: 3 Years Follow-up Results

Objective: It is crucial to identify the high-risk group in acute coronary syndrome (ACS) patients who underwent percutaneous coronary intervention (PCI). To date, various stratification tools have been developed to predict adverse events. However, the PR interval is a readily available parameter in routine clinical practice. This study aimed to investigate the role of the PR interval in predicting major adverse cardiovascular events (MACE) in patients with ACS who were performed PCI. Methods: Patients diagnosed with ACS and who underwent PCI between January 2015 and July 2018 were included in the study. Patients were followed up for an average of 3.2 years. Electrocardiogram was obtained from all patients on admission to the hospital. The PR interval was measured by the semi-automatic application tool. The primary outcome was all-cause mortality, new-onset decompensated heart failure, cerebrovascular event, and recurrent revascularization. Results: The mean age of total 177 ACS patients was 58.7 +/- 10.3 years and 150 (84.7%) of them were male. MACE developed in 38 patients (21.4%) who were older (p<0.001) with a male preponderance (p=0.032). The PR interval was shorter in the MACE (+) group than the MACE (-) group (154.2 +/- 21.2 vs 164.1 +/- 18.1 ms, p=0.004). Backward multivariable Cox regression analysis revealed that male gender [hazard ratio (HR)=3.667, 95% confidence interval (CI): 1.501-8.961, p=0.004], PR interval [HR=0.981, 95% CI:0.961-0.996, p=0.019], and left ventricular ejection fraction [HR=0.906, 95% CI:0.873-0.941, p<0.001] were independent predictors of MACE during long-term follow-up. Conclusion: The PR interval and male gender were independent predictors of long-term MACE in patients with ACS without atrioventricular conduction defect.