[Isolated replacement of the tricuspid valve with a bioprosthesis. Apropos of 22 cases in Abidjan].

The authors reviewed the operative and function results of 24 isolated tricuspid valve replacements with bioprostheses in 22 patients. The patient population was young (average age 15 +/- 8 years). The surgical indication was massive tricuspid regurgitation due to chronic parietal endocarditis in 19 cases and to bacterial endocarditis in 3 cases. Tricuspid valve replacement was associated with 19 right ventricular endocardectomies, 2 direct closures of ventricular septal defects, 2 Wooler mitral valvuloplasties and 1 pericardectomy. The operative mortality was 13.5% and the secondary mortality 13.5%. Of the 16 survivors, 13 are in the NYHA Class I with no regular medical therapy. Their cardiothoracic ratio has slightly decreased. Two patients have permanent atrial fibrillation, and 12 have acquired definitive complete right bundle branch block. Eight of these patients had significant improvement of atrial and right ventricular pressures, of Yu's index and cardiac index at postoperative catheterisation. Three of the 16 patients developed progressive calcific degeneration of their bioprostheses. They are among the 6 patients who have been followed up for more than 3 years. There was no mortality at reoperation. Isolated tricuspid valve replacement by bioprosthesis was chosen despite the young age of these patients because of the disadvantages of mechanical prostheses which are associated with a much higher mortality related to incarceration and thrombosis of the prosthesis. The relatively high operative and secondary mortality in this series of isolated tricuspid valve replacement compared to mitral, aortic or micro-aortic valve replacement, is related to the gravity of the underlying causal pathology.