Abstract
Background
The recently published Cardiovascular Outcomes Assessment of the mitraclip Percutaneous Therapy for Heart Failure Patients with Functional Mitral Regurgitation (COAPT) randomized trial has shown a huge benefit in the survival of patients with systolic heart failure and functional mitral regurgitation treated with MitraClip. However, patients in COAPT were highly selected and the clinical course in real-world patients with and without fulfilment of the trial inclusion criteria is unclear.
Methods
Our study examined the clinical outcome in consecutive patients from our Heart Centre with reduced left-ventricular ejection fraction (EF<50%) undergoing mitraclip for mitral regurgitation of dominant functional etiology by the presence of the inclusion criteria of the COAPT trial (left ventricular ejection fraction >20%, left ventricular end-systolic dimension <70 mm, non-commissural primary jet, estimated pulmonary artery systolic pressure <70 mmHg, mitral valve orifice area >4 cm2, no prior mitral valve leaflet surgery or any currently implanted prosthetic mitral valve or any prior transcatheter mitral valve procedure). The composite endpoint of all-cause mortality or heart failure hospitalization and the endpoint of heart failure hospitalization were analysed.
Results
Among 123 patients who underwent mitraclip implantation 60.2% fulfilled the inclusion criteria of COAPT. Overall, 54 patients (46.6%) died or were hospitalized for heart failure during a median follow-up time of 19 months. The composite endpoint was significantly less frequent (p=0.01) in patients fulfilling the COAPT selection criteria than in those not fulfilling the criteria, with an estimated 1-year event rate of 24.6% vs 49.1%. Patients with COAPT inclusion criteria had a 49% lower hazard of the composite endpoint (95% CI 12–70%, p=0.015). Heart failure hospitalization was significantly less frequent (p=0.039) in patients fulfilling COAPT selection criteria than in those who did not, with an estimated 1-year event rate of 19% vs. 36.8%. Patients with COAPT inclusion criteria had a 50% lower hazard for heart failure hospitalization (95% CI 1–75%, p=0.046). Of note, the 1-year all-cause mortality in our patients fulfilling COAPT inclusion criteria was lower compared to the renowned COAPT trial (10% vs. 19%).
Conclusion
In this single center study the outcome of patients with functional mitral regurgitation undergoing mitraclip therapy was significantly worse in patients not fulfilling COAPT inclusion criteria, indicating that these criteria might help identify futility. The remarkable difference in outcome between real-world patients and COAPT trial patients warrants further study to elucidate underlying causes, which might affect the transferability of the COAPT results.
MitraClip in patients with functional mitral regurgitation and advanced heart failure - Single centre experience
