Impact of loop diuretics on outcome after Transcatheter Tricuspid Valve Repair (TTVr)

Background: Severe tricuspid regurgitation (TR) leads to right heart failure with volume overload. Due to frailty and comorbidities, most elderly patients are deemed inoperable and first treated with medical treatment, preferably with loop diuretics. Regrettably, conservative treatment alone shows unfavorable outcomes. Transcatheter tricuspid valve repair (TTVr) has become a viable interventional treatment option for these patients. However, it remains unclear if diuretic treatment changes after TTVr or if there is an association between daily diuretic dose and outcome after TTVr.

Aim: To determine whether the dose of loop diuretics in TR patients can be reduced after successful TTVr and furthermore if high dose is associated with poor outcome. 

Methods: In a retrospective single-center study, a total of 226 patients treated with TTVr between 2017 and 2022 were analyzed regarding clinical outcome (i.e. combined endpoint of hospitalization and death) depending on the daily dose of loop diuretics before intervention. The median follow-up time was 388 days (IQR 209).

Results: The median age of the study population was 80 years, 67% were female. Most patients presented highly symptomatic with dyspnea according to NYHA class III/IV (85%), and 58% had persistent peripheral edema the day before intervention despite optimal pretreatment. The cohort was stratified into two groups receiving high or low diuretic dose, for which the optimal cutoff value was calculated at 95mg in receiver-operating characteristics analysis. Technical and procedural success at 30 days according to TVARC criteria were lower in high diuretics dose group, as were survival (mortality 52.5% vs 20.5% in low diuretics dose group, p=<0,001) and hospitalization due to decompensation (28.8% vs 15.6%, p=0.026). High diuretics dose of more than 95mg furosemide-equivalent dose showed an independent association with the occurrence of long-term follow-up hospitalization or death in multivariable analysis (HR 2.841; 95% CI 1.705-4.733; p=<0.001). 

A reduction of at least 1 NYHA class was achieved in 68% of patients after TTVr, irrespective of diuretic dose (65% vs. 69% in low diuretic dose group, p=0,648). Daily diuretic dose remained stable after TTVr with a median delta between baseline and long-term follow-up dose of 0 (IQR 40, p=0,862).

Conclusion: Patients with high dose of diuretics undergoing TTVr were more likely to have a poorer procedural outcome and were at higher risk for hospitalization or death during follow-up. However, these patients still showed improved symptoms measured by NYHA class and did not have a significant need for increase in loop diuretics dose. This might prevent associated side-effects of high-dose diuretic intake such as electrolyte derailment, hypovolemia and progressive renal impairment. 

Figure 1: Kaplan-Meier plot for freedom of event (hospitalization or death) comparing high and low dose of diuretics groups. High dose of diuretics was defined as 95mg furosemide or less, low dose of diuretics as more than 95mg respectively. There was a significantly higher rate of events in the high dose of diuretics group (p=<0,001).