The Birmingham Trial of permanent pacing in patients with intraventricular conduction disorders after acute myocardial infarction.

Patients surviving 2 weeks after myocardial infarction who had persistent conduction disorder (right bundle branch block alone or associated with left anterior or posterior hemiblock [LPH] or LPH alone) were allocated at random to permanent pacing or control groups. Throughout follow-up, up to 5 years, there was no significant difference in survival: at 2 years 14 of 23 (61%) of paced patients had died compared with 11 of 27 (41%) control patients. Progression of conduction disorder was not observed and measurement of infranodal conduction time (HV interval) did not predict outcome. Ventricular tachyarrhythmias were an important cause of death in these patients and pacing appears to offer no benefit.