Long-Term Outcome in Patients With Inferior Myocardial Infarction and Complete Atrioventricular Block

AbstractSome studies have reported increased short-term mortality and higher incidence of multivessel coronary artery disease in patients with inferior myocardial infarction and complete heart block, but information is lacking on clinical outcome after hospital discharge. Therefore, data were obtained and analyzed in 749 patients who were admitted with inferior myocardial infarction to four different centers and followed up for 1 year. Six hundred fifty-four patients (Group 1) did not have complete heart block and 95 (Group 2) had complete heart block during their hospital stay (incidence rate 12.8%).Compared with Group 1, Group 2 patients were older (66 versus 61 years, p < 0.01), more often had signs of left ventricular failure (p < 0.001) and had higher peak creatine kinase values (1,840 versus 1,322 IU/liter, p < 0.001). The in-hospital mortality rate was higher in Group 2 than in Group 1 (24.2 versus 6.3%, p < 0.001). However, at discharge there was no difference between Group 1 andGroup 2 in clinical characteristics, left ventricular ejection fraction (0.52 ± 0.12 versus 0.52 ± 0.11) or incidence of complex ventricular arrhythmias on ambulatory electrocardiographic monitoring. Furthermore, during the year after hospital discharge, patients in Groups 1 and 2 did not have significantly different mortality rates (6.4 versus 10.1%, p = NS). The incidence rate of reinfarction (4%) was the same in Groups 1 and 2. The incidence of coronary artery bypass surgery was slightly but not significantly higher in Group I compared with Group 2 (11 versus 4%).It is concluded that patients with inferior myocardial infarction and complete heart block have a high in-hospital mortality. However, by multivariate analysis, the occurrence of complete heart block is no longer an independent predictor of poor prognosis after hospital discharge. Patients with complete heart block who survive to leave the hospital have a favorable clinical outcome