Impact of High-Degree Atrioventricular Block on No-Reflow Phenomenon and Prognosis in Patients with St-Segment Elevation Myocardial Infarction

Abstract

Introduction: Although it has been established that high-degree atrioventricular block (HAVB) is associated with mortality in the course of ST segment elevation myocardial infarction (STEMI), the mechanisms by which this AV block cause mortality are not yet fully understood. In this study we aimed: (i) to investigate the relationship between HAVB and no-reflow, which has been repeatedly shown to be associated with both short- and long-term mortality; (ii) to determine the effect of both HAVB and no-reflow on in-hospital and long-term mortality. Patients and Methods: A total of 1.217 patients who underwent primary percutaneous coronary intervention (pPCI) were divided into two groups, according to HAVB development, and were further divided according to no-reflow development. Independent predictors of no-reflow were investigated. Furthermore, patients were compared in terms of in-hospital and long-term mortality. Results: In the present study, 47 patients (3.8%) suffered from HAVB and 150 patients (12.3%) had no-reflow. HAVB was an independent predictor of no-reflow [odds ratio (OR): 3.127, 95% confidence interval (CI): 1.215-9.056; p= 0.006]. In survival analysis, both HAVB and no-reflow were associated with in-hospital (19.1% vs. 3.2%; p< 0.001 and 10.7% vs. 2.9%; p< 0.001, respectively) and long-term (15.7% vs. 6.2%; p= 0.037 and 14.1% vs. 5.5%; p< 0.001, respectively) mortality. Conclusion: To our knowledge, this is the first study in the literature to examine the effect of HAVB on reperfusion success. In this study, we found that HAVB emerged with STEMI is associated with long-term mortality and to short-term mortality. Also HAVB was an independent predictor of no-reflow, and patients who had no-reflow had a worse prognosis both in short- and long-term follow-up.