Clinical impact of elevated tricuspid valve gradient after transcatheter tricuspid valve repair

Abstract Background Transcatheter edge-to-edge tricuspid valve repair (TTVR) is a novel treatment approach in heart failure patients with moderate-to-severe tricuspid regurgitation (TR) at prohibitive surgical risk. Aim The aim of this study was to investigate the mean tricuspid valve gradient (TVG) over time and compare patient characteristics and outcome of patients with a post-procedure TVG of >3 mmHg vs. ≤3 mmHg. Methods All patients who were treated between between March 2016 and October 2018 with TTVR were included in this analysis. Trans-thoracic echocardiographic assessment of TVG was performed pre-procedurally, pre-discharge, after 1, 6, and 12 month. Results We treated 145 consecutive patients with moderate-to-severe secondary TR with TTVR. Patients were treated with TTVR for severe TR alone (70 patients) or in combination with mitral valve repair for concomitant severe mitral regurgitation and severe or moderate-severe TR with significant annulus dilatation (75 patients). One clip was implanted in 17 (11.7%), 2 clips in 83 (57.2%), 3 clips in 40 (27.6%) and 4 clips in 4 patients (2.8%). Reduction of at least 1 degree of TR was achieved in 136 Patients (93.8%). The median baseline TVG of all patients was 1 mmHg [Inter Quarter Range, IQR 1.0–1.4 mmHg]. The median TVG – measured at post-procedural trans-thoracic echocardiogram pre-discharge – increased to 2 mmHg [IQR, 1.6–3.0 mmHg] and remained constant up to 12 month (2.0 mmHg [IQR 1.0–2.0 mmHg). Of these, twenty-five patients showed an elevated TVG >3 mmHg post-procedurally. Patients with TVG >3 mmHg were younger (73.1±11.0 vs. 77.5±9.2 years, p=0.038) and presented with lower levels of pro-BNP at baseline (median 2276 ng/l [IQR, 906–5150] vs. 4182 ng/l [2310–8629], p=0.008) compared to patients with TVG ≤3mmHg. All other baseline characteristics were balanced. There were no differences in procedural success (TR reduction of ≥1 grade in 96% vs. 93.3%, p=0.946) and number of clips implanted (p=0.697). At one month follow-up there were no differences in NYHA class (NYHA class ≥3 in 24% vs. 30.8%, p=0.559), quality of life measured with the Minnesota Living With Heart Failure questionnaire (32.0±22.9 vs. 31.1±16.3, p=0.833), 6 minute walking distance (255.5±140.6 vs. 250.5±111.7 metre, p=0.872). The clinical endpoints 1-year mortality (HR 1.07; 95% CI [0.43–2.65], p=0.88) and the combined endpoint mortality and hospitalization for heart failure at one year (HR 1.07; 95% CI [0.46 to 2.48], p=0.88, see Figure) did not differ between patients with a TVG >3 mmHg vs. patients with a TVG ≤3mmHg. Figure 1 Conclusion TTVR results in a small increase in the tricuspid valve gradient, which remains constant up to one year. A small cohort of patients shows an elevated TVG higher than 3 mmHg after the procedure. This elevation has no impact on NYHA class at 1 month and the clinical endpoints mortality and hospitalization for heart failure at 1 year.