THE PRESENCE and duration of acute rheumatic carditis in children is often difficult to determine clinically. Laboratory aids currently used have not given incontrovertible results. In recent years the electrocardiograph has been employed as an objective aid in establishing the diagnosis of acute carditis. Considerable difference of opinion exists concerning the frequency of electrocardiographic changes in acute rheumatic fever. Sokolow1 reported electrocardiographic changes (excluding Q-T interval abnormalities) in 21 per cent of 700 cases. These changes consisted of (1) conduction defects, such as partial or complete auriculoventricular block; (2) T wave changes, such as inversion of the T wave in leads I, II or IV or diphasic or flat T waves in leads I and IV, and (3) abnormal rhythms.
Recently Taran and Szilagyi2 have stimulated interest in the importance of the measurement of the duration of electrical systole (Q-T interval) as an aid in the diagnosis and