Tricuspid valvular disease in the patient with chronic pulmonary thromboembolic disease.

Chronic thromboembolic pulmonary hypertension is associated with right ventricular dilatation, high right-sided filling pressures, and functional tricuspid regurgitation. The tricuspid regurgitation resulting from this disease has been postulated to be caused by tricuspid annular dilatation with displacement of the papillary muscles. Pulmonary endarterectomy is an operation that corrects the pulmonary hypertension resulting from chronic thromboemboli. As a result of this operation, most patients show significant improvement in tricuspid valve function. Thus, pulmonary endarterectomy is one of the few cardiac operations in which surgery remote to a valve restores valve function. This review analyzes the factors responsible for changes in tricuspid valve regurgitation after pulmonary endarterectomy and provides a strategy to predict the small subset of patients who will not show improvement in tricuspid valve function after this operation.