Evolution of valve damage in Sydenhamʹs chorea during recurrence of rheumatic fever

Background The evolution of valve damage during a recurrence, in a patient who did not have apparent carditis in the initial attack of Sydenhamʹs chorea, has been a subject of debate. Methods Thirty-six patients with an initial episode of acute rheumatic fever and Sydenhamʹs chorea (3 patients with subclinical mitral regurgitation) were followed up prospectively for 5 years. Clinical examinations and transthoracic color Doppler echocardiography were done for each patient at initial attacks of Sydenhamʹs chorea and at recurrences of rheumatic fever. Results Six recurrences of rheumatic fever occurred in 6 of the 36 patients. One recurrence developed in the regular secondary prophylaxis group (27 patients) with a recurrence rate of 0.007 per patient-year. Three of the 18 patients who initially had no heart murmur and no echocardiographic finding of valvular regurgitation had three recurrences of pure chorea with no echocardiographic evidence of significant valvular regurgitation. Interestingly, one of the 3 patients with previous pure chorea and echocardiographic finding of significant mitral regurgitation had a recurrence of pure chorea and new echocardiographic evidence of mitral, aortic and tricuspid regurgitations. Furthermore, two recurrences occurring in 2 of the 15 patients with previous carditis developed echocardiographic evidence of new carditis. Conclusions Rheumatic recurrence can develop new valve damage evident by echocardiography for the patient with pure Sydenhamʹs chorea who had previous subclinical valvulitis. Longer duration of secondary prophylaxis is recommended to prevent a recurrence of rheumatic fever in the patient with pure Sydenhamʹs chorea who initially had subclinical valvulitis.