The electrocardiographic syndrome of short P-R interval and broad QRS complexes: A clinical study of 80 cases

Abstract

1. 1. An analysis is made of 80 patients with the syndrome of short P-R interval and broad QRS complexes, seen at the University of Texas Medical Branch. 2. 2. Incidence of the syndrome is infrequent, being 1.5 per 1,000 patients. 3. 3. Ages varied from 9 1 2 months to 82 years, and 35 were over 40 years old. There was a slight predominance of males (60 per cent). Incidence in the Negro was infrequent. 4. 4. Forty-eight patients (60 per cent) had no evidence of organic heart disease. Nineteen had coronary heart disease. Seven showed clinical evidences of acute myocardial infarction, but the ECG diagnosis was generally obscured by the broad QRS complexes. 5. 5. There was a high incidence of psychiatric diagnoses (26 per cent). Seven patients subjected to electroshock and deep insulin shock therapies tolerated them well. 6. 6. Successive tracings characteristically showed considerable variation. Even in otherwise diagnostic tracings, the P-R interval may occasionally exceed 0.12 second, but the concertina effect can be demonstrated. 7. 7. There were 48 patients showing a QRS configuration of the Group B of Sodi-Pallares, and 13 patients of Group A. Sixteen had indeterminate patter 8. 8. Effects of exercise, carotid sinus pressure, and various drugs on the ECG manifestations were confirmed. False positive Master exercise tolerance tests were demonstrated. 9. 9. Forty-five patients (56 per cent) had arrhythmias, and we observed 29 with atrial tachycardia, 6 with atrial fibrillation, and 2 with atrial flutter. In 14 patients, the arrhythmias complicated organic heart disease. 10. 10. Broad QRS complexes during the arrhythmias were more frequent than previously reported, and simulated ventricular tachycardia and ventricular fibrillation. 11. 11. Two older patients died suddenly, presumably as a result of a mechanism disorder. 12. 12. The usual methods of control of atrial tachycardia were found efficacious. Pronestyl intravenously under ECG control appeared to be the most effective method of reversion of atrial fibrillation.