A 53-year-old patient with corrected transposition of the great arteries developed complete heart block with fainting episodes. After temporary pacing through the endocardium of the venous (anatomically left) ventricle, a permanent epicardial pacemaker was implanted. This case shows the progressive nature of the atrioventricular conduction disturbances, which are very common in association with this congenital cardiac anomaly.Congenital corrected transposition of the great arteries (CTGA) is usually accompanied by additional cardiac malformations but may occur without associated defects (Rotem and Hultgren, 1965). Atrioventricular conduction disturbances are found in almost half of the patients (Schiebler et al, 1961;Friedberg and Nadas, 1970), the commonest being a prolonged PR interval. When complete heart block is present, the QRS complex is narrow, the ventricular rate is usually greater than 50/min, and rarely dominates the clinical picture, which is determined by the additional anatomical abnormalities (Shem-Tov et al, 1971). The few reported cases of CTGA in whom complete heart block necessitated pacemaker implantation were in children who developed this conduction disturbance in infancy, early childhood, or adolescence (Friedberg and Nadas, 1970) and only in one instance in an adult patient (Berman and Adicoff, 1969).We describe a middle-aged patient in whom CTGA was first diagnosed at the age of 49 and who at the age of 53 developed complete atrioventricular block that required pacemaker implantation. This is the second reported adult case in whom a permanent pacemaker was implanted to treat complete heart block in the presence of CTGA.
Case reportA 53-year-old clerk was transferred to the department of cardiology at the Rambam Medical Centre with a three-day history of pronounced weakness, dyspnoea on minimal effort, and two episodes of Stokes-Adams attacks. During these episodes a slow heart rate (30/min) was recorded, and the electrocardiogram showed complete atrioventricular block.In 1970, at the age of 46, he had begun to suffer from recurrent episodes of left heart failure and was treated with digitalis and diuretics. As he did not fully respond to this treatment he was admitted in 1973 to the heart institute of the Haim Sheba Medical Centre, where right and left heart catheterisations were performed, and the diagnosis of CTGA was established. In addition, a moderate degree of aortic regurgitation and slight left atrioventricular valve regurgitation were shown. The electrocardiogram in 1973 showed sinus rhythm with a PR interval of 0-36 seconds. The patient was discharged home, remained well, and continued to work.At the present admission he was dyspnoeic and orthopnoeic with an irregular pulse of 54/min and a blood-pressure of 120/70 mmHg. There was no jugular venous congestion. Fine crepitations were heard at both lung bases. The apex beat was not palpable, but he had a left parasternal heave. A single and accentuated second heart sound, a 3/6 ejection systolic murmur, and a 2/6 early d...