Programmed stimulation after anterior myocardial infarction complicated by bundle branch block--late ventricular tachyarrhythmias and outcome.

One hundred and thirty consecutive patients with anterior myocardial infarction complicated by bundle branch block were retrospectively analyzed. Sixty died within 1 week of infarction. Of the remaining 70 patients, 36 had electrophysiology study with programmed stimulation 8-90 (mean 20) days after infarction. Of these, nine patients (35%) who clinically had not manifested either ventricular tachycardia or ventricular fibrillation more than 72 hours after infarction, had inducible ventricular tachycardia which was sustained more than 30 seconds in eight patients. By contrast, assessment of atrioventricular conduction added little to clinical management, long-term follow-up, extending up to 127 months, was available both in those patients whose therapy was directed by electrophysiology study, and was assessed among the other 34 patients who survived at least 7 days after myocardial infarction, but who did not undergo electrophysiology study. While the overall mortality was 55%, the majority of deaths (22/35) occurred within 4 months of infarction and many long-term survivors enjoy a gratifying quality of life. Although programmed stimulation in survivors of anterior myocardial infarction complicated by bundle branch block may identify a high risk subgroup, a prospective randomized trial is required to define the utility of more aggressive stimulation protocols following NASPE recommendations, to identify subgroups of patients in whom newer therapeutic interventions, including antiarrhythmic agents, electrical devices and surgery may be indicated.