Early Surgery for Isolated Severe Tricuspid Regurgitation Improves Outcomes

Surgery should be considered for isolated severe tricuspid regurgitation (TR) before overt symptoms develop. So concludes a retrospective study of 159 patients who underwent isolated surgical tricuspid valve (TV) repair or replacement at Cleveland Clinic. The study was published in the Journal of Thoracic and Cardiovascular Surgery (2023;166[1]:91-100).

The investigation found higher operative mortality and significantly worse composite morbidities in patients who had symptomatic severe TR preoperatively compared with asymptomatic patients with severe TR and right ventricular dilation and/or dysfunction. The study is one of the largest single-center series of isolated TV surgery to date, and the first to compare surgeries by indication.

“We found that taking an earlier approach to intervening for isolated TR saves lives,” says senior and corresponding author Milind Desai, MD, MBA, a cardiologist and Director of Clinical Operations in Cleveland Clinic’s Department of Cardiovascular Medicine. “Waiting for symptoms to appear is associated with many comorbidities and higher patient risk for surgery.”

Established indications for isolated TV surgery are few

Isolated TV surgery entails higher risk of operative mortality than isolated operations on other heart valves or on coronary arteries. For this reason, it is not often performed even at high-volume centers like Cleveland Clinic, despite poor outcomes associated with severe TR.

The latest American College of Cardiology/American Heart Association guideline for valvular heart disease has no class I indications for isolated TV surgery, while European Society of Cardiology (ESC) guidelines have just one such indication — for severe symptomatic isolated TR.

Study design and findings

The study population consisted of 159 patients who underwent isolated TV surgery at Cleveland Clinic between 2004 and 2018. Of those, 115 were symptomatic (“class I group,” per the ESC guidelines) and 44 were asymptomatic (“early surgery group”) at the time of surgery. At baseline, all patients in the early surgery group had one of the following: both right ventricular dilation and dysfunction (n = 12; 26.8%), right ventricular dilation alone (n = 23; 52.7%) or right ventricular dysfunction alone (n = 9; 20.5%).

Seventeen surgeons performed the procedures. Valve repair was performed in 73.0% of class I patients and 79.5% of early surgery patients (P = 0.54). More than 90% of valve replacements were done using bioprosthetic valves.

The two groups differed significantly at baseline in several respects: class I patients were older (mean age of 61.7 vs. 54.4 years; P = 0.016); had a higher prevalence of secondary TR (65.2% vs. 38.6%; P = 0.004); had more symptoms (by definition), including right heart failure, higher New York Heart Association class and greater likelihood to be in a critical preoperative state; and more often had a history of cardiac surgery, cardiac implantable electronic device, heart failure, atrial fibrillation or chronic lung disease than the early surgery patients.

Key findings were as follows:

• Operative mortality occurred in 8 patients (7.0%) in the class I group vs. no patients (0.0%) in the early surgery group (P = 0.107).
• Composite morbidity occurred in 41 patients (35.7%) in the class I group vs. 8 patients (18.2%) in the early surgery group (P = 0.036).

The early surgery group had superior survival rates over the length of the study (mean follow-up, 5.1 ± 4.0 years). Multivariable analysis revealed that mortality during follow-up (the primary endpoint) was associated with the following factors:

• Class I indication (vs. early surgery) ― hazard ratio (HR) = 4.62 (95% CI, 1.09-19.7), P = 0.038
• Age (per year) ― HR = 1.03 (95% CI, 1.00-1.07), P = 0.046
• Diabetes mellitus ― HR = 2.50 (95% CI, 1.13-5.55), P = 0.024

“Although differences in outcomes between the two groups were mostly explained by baseline clinical differences, the early surgery group was still better off after adjustment for these differences,” Dr. Desai observes.

Guidance for improving outcomes

The study authors emphasize the following takeaways from their findings:

• Don’t wait for symptoms. “Patients with isolated TR before having overt symptoms should be monitored with quantitative right heart and TR measures on cardiac imaging — such as tricuspid regurgitant volume (≥45 mL on echocardiography, >35 mL on cardiac MRI) or regurgitant fraction (>30% on cardiac MRI) and right ventricular strain (less negative than −19% on echo), as shown in two of our group’s recent studies [here and here] — so that surgery can be considered once the aforementioned imaging thresholds are met,” says first author Tom Kai Ming Wang, MBChB, MD, staff cardiologist in Cleveland Clinic’s Section of Cardiovascular Imaging. “To further aid patient management and surgical selection, we recently developed a novel risk score for predicting one-year mortality in isolated TR to assist in risk stratification for these high-risk patients.”
• Concentrate surgeries at centers of excellence. “Isolated TV surgery is high-risk and infrequently performed, so we strongly recommend that it be done at a high-volume institution for the best results,” says co-author A. Marc Gillinov, MD, Chair of Thoracic and Cardiovascular Surgery at Cleveland Clinic. The authors note that morbidity and mortality outcomes in this study compare favorably with other recent reports, likely due to surgeon experience in all TV operations, patient selection, and attentive perioperative management.
• Consider transcatheter approaches, especially for high-risk surgical candidates. “Percutaneous approaches to TV repair and replacement are emerging in an effort to improve outcomes and widen the candidate pool to safely undergo intervention,” says Amar Krishnaswamy, MD, Chair of Interventional Cardiology at Cleveland Clinic, who wasn’t involved in the study. “Outcomes from this study can provide surgical benchmarks for studies of isolated TV catheter-based approaches.”

“Although this study has the limitations of a single-center observational investigation, it has the advantage of reflecting real-world practice,” Dr. Desai notes. “Randomized controlled trials are now needed to compare outcomes of surgical, transcatheter and medical management, along with their timing and indications.”