Tricuspid Valve Repair

Excerpt

Tricuspid regurgitation is the most common indication requiring tricuspid valve repair. An estimated 1.6 million people in the United States have moderate to severe tricuspid regurgitation, compared to only a few thousand tricuspid valve repair procedures performed annually. According to the United States National Registry, 5005 primary tricuspid valve procedures were performed with in-hospital mortality of 8.8% over 10 years. Due to convincing evidence available now that untreated severe tricuspid regurgitation results in a worsened outcome, there is an increased interest in the treatment of sole tricuspid valve pathologies. Study results have shown that tricuspid regurgitation is associated with a higher incidence of cardiac events and mortality in patients with congestive heart failure.

Repairing the tricuspid valve presents unique challenges compared to mitral valve repair, primarily due to its intricate anatomy. The tricuspid valve has 3 leaflets, a saddle-shaped, dynamic annulus, and a complex subvalvular apparatus, making its repair more demanding. Late referrals for tricuspid valve surgery further complicate treatment and contribute to poorer patient outcomes. Research results indicate moderate to severe tricuspid regurgitation is associated with reduced survival rates. As a result, tricuspid valve surgeries are becoming increasingly common to enhance survival and quality of life. Tricuspid valve disorders are generally categorized into congenital and acquired conditions. Repair strategies often extend beyond simple annular reduction techniques to restore the intricate functional interactions among the valve's anatomical components.

Tricuspid regurgitation is frequently observed in patients undergoing mitral valve surgery for degenerative mitral regurgitation. Observational studies primarily inform current guidelines for managing tricuspid regurgitation during mitral valve surgery. There is consensus that severe tricuspid regurgitation is unlikely to resolve following left-sided cardiac surgery and should be addressed during the initial procedure, as late reoperations for severe tricuspid regurgitation in patients with right heart failure carry a high risk of perioperative mortality.

The management of milder forms of tricuspid regurgitation remains a subject of debate. Treatments for left-sided cardiac disease often lead to improvements in tricuspid regurgitation, driven by factors such as right ventricular remodeling and reductions in pulmonary artery pressures. However, mild to moderate tricuspid regurgitation left untreated during left-sided cardiac surgery progresses in about 25% of patients, potentially leading to reduced survival and functional outcomes. Risk factors for progression include annular dilation (≥40 mm or ≥21 mm/m²), right ventricular dysfunction, leaflet tethering, pulmonary hypertension, atrial fibrillation, and transvalvular pacing or defibrillator leads.

Observational studies and results from a small randomized trial with unblinded endpoints suggest that repairing the tricuspid valve in patients with moderate or less-than-moderate regurgitation accompanied by annular dilation may reduce disease progression and improve outcomes. Nonetheless, universal adoption of concomitant tricuspid valve repair faces challenges, including the potential need for permanent pacemaker implantation due to conduction disturbances, prolonged cardiopulmonary bypass times, and the rare necessity for tricuspid valve replacement instead of repair. Additionally, not all patients experience progression of tricuspid regurgitation. As a result, there is significant variability in how less-than-severe tricuspid regurgitation is managed during left-sided cardiac surgery. Reported rates of tricuspid valve repair during mitral valve procedures range widely, from 5% to 75%.

Most patients with significant tricuspid regurgitation have traditionally been treated with medical management, as isolated surgical intervention for tricuspid regurgitation has been linked to high rates of periprocedural complications and in-hospital mortality. These poor outcomes are often attributed to late referrals when patients have advanced right-sided heart failure and the high prevalence of prior left-sided heart surgeries among candidates. This has underscored the need for minimally invasive, catheter-based therapeutic options to address tricuspid regurgitation more effectively.

In recent years, several transcatheter devices have been developed for tricuspid valve interventions, with transcatheter tricuspid edge-to-edge repair (T-TEER) emerging as the most commonly used approach. Among these devices, the TriClip (Abbott) has been the first and most widely adopted for T-TEER. However, evidence supporting its safety and effectiveness primarily derives from the results of retrospective studies that include real-world, unselected patient populations or data collected in highly selected cohorts through prospective trials, such as the TRILUMINATE randomized study. Transcatheter therapies for the tricuspid regurgitation field are advancing rapidly and moving closer to becoming a standard component of routine clinical care.