The Diagnosis and Treatment of Tricuspid Regurgitation

Abstract

Background: It is estimated that 6% of persons over age 75 have clinically relevant tricuspid regurgitation (TR). This condition carries a high mortality and is of particular interest because of the recent development of new interventional treatments.

Methods: This review is based on publications that were retrieved by a selective search in the PubMed database for randomized controlled trials (RCTs), observational studies, registry studies, expert recommendations, and current international guidelines.

Results: The evidence reveals that TR is an independent cause of mortality. Mortality is correlated with the severity of TR: approximately 35% of patients with severe TR and right heart failure die within 1 year, and about 60% within 3 years. The clinical course varies depending on the etiology (primary TR, atrial/ventricular secondary TR, association with pacemaker systems). In the outpatient setting, timely diagnosis by transthoracic echocardiography is crucial. The options for pharmacotherapy are essentially limited to diuretic treatment (grade 2a recommendation). Early referral to a specialized heart valve center is essential for the prevention of irreversible damage of the right heart and secondary end-organ damage, including cardiohepatic and cardiorenal syndromes. In the heart valve center, an extended diagnostic evaluation with multimodal imaging is followed by a case discussion by the interdisciplinary cardiac team, with individual evaluation of the treatment options. The first randomized controlled trial of treatment for TR yielded a win ratio of 1.48 (95% confidence interval, [1.06; 2.13]) for interventional treatment (edge-to-edge repair) compared to optimal medical therapy.

Conclusion: As the understanding of tricuspid regurgitation improves, strategies for its interventional treatment are undergoing steady development, with the aim of lowering the mortality of this condition.

Figure 1

Pathomechanism of tricuspid regurgitation. Tricuspid regurgitation (TR) is a chronic progressive disease. A coaptation defect of the tricuspid valve leaflets causes right ventricular (RV) dilatation and annular dilatation. This worsen the coaptation defect and results in a vicious circle with increasing TR. Sevee TR is further subdivided into grade 3 (severe), grade 4 (massive), and grade 5 (torrential). Progressive TR leads to progressive right heart failure. RV, Right ventricle. Modified from Hahn et al. (8).

Figure 2

Multimodal assessment of tricuspid regurgitation (TR) carried out at the heart valve center for evaluation of the TR and the potential treatment options. The work-up starts with extended transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE), followed by right heart catheterization, for hemodynamic assessment, and left heart catheterization. Should edge-to-edge repair not seem ideal on anatomic grounds, computed tomography (CT) can be considered to help plan alternative interventional treatment options. Magnetic resonance imaging (MRI) can furnish additional information on right structure and function as well as on blood flow and the regurgitation through the tricuspid valve. 3D-RVEF, Three-dimensional right ventricular ejection fraction; PA, pulmonary artery; PISA, proximal isovelocity surface area; RA, right atrium; RV, right ventricle

Figure 3

Treatment algorithm for use in persons with isolated severe tricuspid regurgitation. Specific tricuspid valve treatment is indicated in patients with isolated symptomatic, severe TR. After extended diagnostic work-up at a heart valve center the individual treatment options are weighed up by the cardiac team. Transcatheter-based edge-to-edge repair by means of clipping (TEER) represents the best available treatment option (see “TEER” in the illustration above; TriClip on the left, PASCAL Ace on the right). In centers with experienced staff this procedure enables very efficient TR reduction with a high degree of safety. In patients who are anatomically unsuited for TEER, alternative treatment options for interventional valve replacement are considered (in the illustration: “Interventional valve replacement (orthotopic)”, Evoque system; “Interventional valve replacement (heterotopic)”, TricValve). If the surgical risk is low (TRI-SCORE ≤ 2 points, corresponding to a < 5% risk of in-hospital mortality with isolated tricuspid valve surgery), primary surgical treatment may be appropriate in individual cases (in the illustration: “Surgical treatment”, Physio Ring). By kind permission of the manufacturers Edwards Lifesciences (Physio Ring, PASCAL Ace and Evoque; Irvine, California, USA), Abbott (TriClip; St. Paul, Minnesota, USA), and P+F Products+Features (TricValve; Vienna, Austria)

Figure 4

Risk score for estimation of in-hospital mortality after isolated tricuspid valve surgery. * Diuretic treatment with ≥ 125 mg furosemide or a corresponding equivalent dose. Modified from Dreyfus et al. (31). eGFR, Estimated glomerular filtration rate; LVEF, left ventricular ejection fraction; NYHA, New York Heart Association; RV, right ventricle