Influence of right bundle branch block on short- and long-term survival after inferior wall Q-wave myocardial infarction

Abstract

Compared with acute anterior wall myocardial infarction, acute inferior wall myocardial infarction generally produces infarcts of smaller size resulting in less reduction of left ventricular ejection fraction and more favorable survival. 1,2 However, subsets of patients with inferior myocardial infarction may be at high risk of death and may benefit from aggressive treatment including thrombolysis. Occurrence of atrioventricular or intraventricular block may identify patients with poor prognosis, and advanced atrioventricular block has been shown to be associated with an increased in-hospital but not long-term mortality compared to patients without such block. 3 Several studies have suggested that the occurrence of bundle branch block (BBB) in patients with myocardial infarction is also a marker of increased subsequent mortality 4–9 but in these previous studies, because of the limited numbers of patients, patients with right and left BBB and those with anterior and inferior myocardial infarction were generally analyzed together. Furthermore, the impact of right BBB on long-term survival after inferior myocardial infarction is unknown. In this study, we analyzed the relation of right BBB to short- and long-term outcome in a large population of patients with inferior Q-wave myocardial infarction.