Clinical characteristics and outcomes of isolated severe functional tricuspid regurgitation in a real-world setting.

Functional tricuspid regurgitation (FTR) is increasingly prevalent in aging populations with heart failure (HF) and has been associated with adverse outcomes. However, the clinical characteristics and prognosis of patients with isolated severe FTR remain poorly defined. We retrospectively reviewed 108,513 consecutive transthoracic echocardiographic examinations performed between June 2013 and March 2025. Isolated severe FTR was defined as severe FTR without significant left-sided valvular disease and preserved left ventricular ejection fraction (LVEF ≥ 50%). The primary endpoint was all-cause mortality, and the secondary endpoint was cardiovascular death or HF hospitalization. Seventy-four patients met the criteria for isolated severe FTR. Patients were predominantly elderly (mean age: 80.9 ± 5.9 years), 54.0% were New York Heart Association functional class III or IV, 70.2% had HF stage C or D, and chronic kidney disease was present in 86.4% of patients. During a median follow-up of 3.1 years, 13 patients (17%) died, and 31 patients (41%) experienced cardiovascular death or HF hospitalization. Therapeutic intervention for TR was performed in only 14 patients (18.9%). Compared with previously reported cohorts of severe mitral regurgitation, aortic stenosis, and aortic regurgitation, patients with isolated severe FTR were older, more symptomatic, and had worse outcomes despite lower intervention rates. In conclusion, in real-world practice, isolated severe FTR predominantly affects elderly patients with advanced HF and multiple comorbidities and is associated with poor outcomes despite preserved LVEF. Relative to other severe valvular heart diseases, isolated severe FTR appears to represent an underrecognized and undertreated high-risk condition.