Quadricuspid pulmonary valve.

Quadricuspid pulmonary valve is a rare finding which is usually discovered post mortem (Hudson, 1965). Its incidence is variously reported from 1 case in 20,000 necropsies (Simonds, 1923) to 5 cases in 5000 necropsies (Dagnini, 1930). Most other reports suggest, however, that the latter figure is the more accurate (Simpson, 1898; Thilo, 1909; de Vries, 1918; Houck, 1929). In reviewing the subject, Kissin (1936) noted that in many of the previously reported cases, quadricuspid pulmonary valves were found to be associated with other congenital abnormalities of the heart. As an isolated finding, this anomaly seems, therefore, to be very rare. The following is an account of four cases of isolated congenital quadricuspid pulmonary valve, and a further one in which the anomaly was associated with rheumatic mitral valve disease. In each instance, the anomaly was an incidental finding at necropsy, and there had been no clinical evidence of a pulmonary valve lesion during life. Four of these cases were encountered within the six months November 1964 to May 1965 in patients who had resided in the Bristol area. In 2 of the 5 patients, there was morbid anatomical evidence of pulmonary regurgitation. In one, there was evidence of pulmonary hypertension, but this was the patient with mitral valve disease. There was no other cardiac abnormality in the other 4 patients.