Tricuspid Regurgitation and Right Heart Dimensions at Early and Late Follow-Up After Orthotopic Cardiac Transplantation

Tricuspid regurgitation is common immediately after cardiac transplantation, but its course over long-term follow-up is not known. This study was performed to determine the prevalence of valvular regurgitation and to evaluate if pulmonary hypertension or right ventricular enlargement were associated with the severity of tricuspid regurgitation at early and late follow-up after cardiac transplantation. Fifty-five patients had hemodynamic and echocardiographic studies performed at 1 week and 2.4 +/- 1.3 years after cardiac transplantation. Right ventricular dimensions were measured and related to the severity of tricuspid regurgitation as assessed by Doppler color flow. There was a fall in right heart filling pressures with decreases in the systolic pulmonary artery pressure (31 mmHg +/- 7 mmHg vs 27 mmHg +/- 7 mmHg, P = 0.0001) and right atrial pressure (8 +/- 5 mmHg vs 6 +/- 4 mmHg, P < 0.01). Sixty-three percent of patients had mild or higher grade tricuspid regurgitation initially and 71% at follow-up (P = NS). The major determinant of tricuspid regurgitation severity at late follow-up was the presence of flail tricuspid leaflets (P < 0.0001). There was an association between the change in grade of tricuspid regurgitation and the change in right ventricular diastolic area (P = 0.002) and the change in tricuspid annulus diameter (P < 0.0001). The prevalence of tricuspid regurgitation remains high at late follow-up after cardiac transplantation and neither pulmonary hypertension nor right ventricular dilatation are prerequisites for tricuspid regurgitation, which can persist in their absence. Flail tricuspid leaflets are the most important predictors of the severity of tricuspid regurgitation following cardiac transplantation.