Critical role of right heart catheterization in the evaluation of the appropriateness of transcatheter repair of severe tricuspid valve regurgitation: a case report

Background: Transcatheter tricuspid valve repair is an increasingly performed procedure, which improves quality of life in selected patients with severe tricuspid regurgitation (TR). For the evaluation of the appropriateness of this procedure, identification of the exact mechanism(s) underlying TR is mandatory. Guidelines recommend right heart catheterization (RHC) as part of the work-up in these patients. Case summary: A 80-year-old man with shortness of breath, atrial fibrillation, and severe TR was referred for transcatheter repair. Echocardiography showed a preserved left ventricular ejection fraction, a dilated right ventricle with impaired function, severe functional TR, and a high probability of pulmonary hypertension (PH). Right heart catheterization revealed a mean pulmonary artery (PA) pressure of 34 mmHg and a mean PA wedge pressure (mPAWP) of 18 mmHg. The PA oxygen saturation was 79%, and an anomalous vessel draining into the superior vena cava with an oxygen saturation of 97% was found, which was identified as partial anomalous pulmonary venous return with a left-to-right shunt (ratio of pulmonary to systemic blood flow of 1.8:1.0). The increased pulmonary blood flow and a mildly elevated pulmonary vascular resistance of 2.3 Wood units resulted in an increased transpulmonary gradient, which added to an elevated mPAWP (heart failure with preserved ejection fraction) led to combined pre- and post-capillary PH. Discussion: This case highlights the importance of RHC in the evaluation of patients with severe TR. Here, TR was the result of right ventricular volume and pressure overload with very limited treatment options, and percutaneous repair was not appropriate.