We reviewed 100 postmortems of patients with pulmonary valvar involvement due to rheumatic heart disease. The patients were divided in two groups: the first group included 59 cases with acute rheumatic lesions of the pulmonary valve. At the time of death, the mean age in this group was 18.4 ± 9.7 years. The second group was formed by 41 patients with chronic rheumatic lesions of the pulmonary valve whose mean age at the time of death was 25± 16.5 years. The percentage of patients who died before the age of25 years was greater in the group with acute as opposed to chronic lesions (p=O.0003). The mean age of the first attack in those with acute lesions was 11.7±7.8 years, as compare to 13.8 ± 5.3 years in those with chronic lesions. All patients but one had at least one attack of the acute rheumatic process. There was no significant difference between the groups regarding the number of acute processes. The length of the acute rheumatic process was similar in both groups. Fifty-five cases having acute lesions, and 38 of those with chronic lesions suffered involvement of all cardiac valves. Three valves were affected in two hearts, while only one heart had two affected valves. Fifteen cases had an associated congenital defect of the pulmonary valve, and we found a significantly greater incidence of rheumatic pulmonary disease in the group with co-existing congenital lesions of the valve (p.O.00001). Three patients undergoing catheterization (21.4%) showed normal, or near normal, pulmonary arterial systolic pressure. Rheumatic damage to the pulmonary valve, therefore, exists in association with plurivalvar rheumatic disease. A congenital lesion of the pulmonary valve predisposes to its involvement in the rheumatic process.