Frequency of Complete Atrioventricular Block Complicating ST-Elevation Myocardial Infarction in Patients Undergoing Primary Percutaneous Coronary Intervention

Objectives: ST-segment elevation myocardial infarction (STEMI) can be associated with many conduction disturbances including complete atrioventricular block (CAVB). CAVB complicating STEMI resulted in an increased mortality before the modern era of primary percutaneous coronary intervention (PCI). The aim of this study was to ascertain the rate and risk factors for CAVB in STEMI patients undergoing rapid reperfusion with PCI. Methods: We analyzed 223 patients presenting with STEMI. Patient characteristics, procedural characteristics, and in-hospital data were compared between patients with and without CAVB. Results: Out of 223 patients, 174 underwent PCI; the majority (87%) was African-American. CAVB was present in 8 patients (4.6%), and 6 of them had RCA occlusion. Independent predictors of CAVB included diabetes mellitus, female gender, lower systolic and diastolic blood pressure, and inferior-lateral/lateral STEMI. Ten patients (5.7%) required temporary pacing at presentation; only 1 patient required permanent pacing before discharge. No patient with anterior STEMI developed CAVB. Conclusions: The incidence and in-hospital mortality rate of CAVB in patients with STEMI who underwent primary PCI was reduced when compared to data from the thrombolytic era. This may be due to faster flow recovery in the infarct-related artery achieved with PCI.