Twenty four patients were reoperated on the tricuspid valve alone between 1967 and 1981. The first operation had been performed for mitral valve disease and consisted of 23 mitral valve replacements and one commissurotomy associated with two aortic valve replacements. The surgical decision with regard to the tricuspid valve at the initial operation had been abstention (10 cases), tricuspid valvuloplasty (10 cases) and tricuspid valve replacement (4 cases). Reoperation on the tricuspid valve is rare (0,2 p. 100 of mitral valve operations, 1 p. 100 of mitro-tricuspid valve operations). The 24 cases were divided into 2 groups: --Group I, in which reoperation was indicated for curable tricuspid lesions: .4 reoperations for prosthetic valve dysfunction (4 mechanical prostheses were responsible for 3 thromboses and 1 perivalvular leak); .3 reoperations for failed valvuloplasty (2 Kay valvuloplasties and 1 Carpentier annuloplasty); .2 reoperations for aggravation of neglected functional lesions at the first operation and which were reoperated after 3,5 and 4,5 years, because of increased dilatation of the annulus; .5 reoperations for aggravation of organic lesions which had been neglected in 3 cases and treated by valvuloplasty in 2 cases. Five prosthetic valve replacements were carried out, on average 17 months after the first operation. --Group II, in which reoperation was unable to improve congestive heart failure; dilatation of the tricuspid annulus was only a consequence of the cardiac failure. The secondary tricuspid valve surgery (5 valvuloplasties, 5 annuloplasties) did not alter the extremely poor prognosis of these patients (5 hospital deaths, 3 postoperative deaths within 2 years).(ABSTRACT TRUNCATED AT 250 WORDS)