Right Bundle-Branch Block Associated with Left Superior or Inferior Intraventricular Block

Abstract

Over an 11-year period, 28 instances of acute myocardial infarction and bilateral bundle-branch block were encountered. Twenty-two of these patients had right bundle-branch block and left axis deviation, and six had right bundle-branch block and block of the inferior radiation of the left bundle. The overall incidence of complete heart block in these 28 cases was 21%. In-hospital mortality for the whole group was 36%, whereas it was 33% for those patients who developed complete heart block. From these results it is concluded that for the patient with bilateral bundle-branch block and acute myocardial infarction the prophylactic insertion of a temporary transvenous pacemaker is not only warranted, but is probably indicated.