Acute cardiac failure following pacing in an adult patient with congenital complete heart block.

A case of an adult patient with congenital complete heart block is reported in whom acute heart failure followed pacemaker implantation. It is uncertain whether the associated cardiomyopathy was present since birth, although right ventricular pacing was probably responsible for further deterioration of myocardial function. Synchronous pacing of both ventricles might be recommended in these patients.