Transapical TMVR in High Risk Patients: Intrepid 5-Year Outcomes

Moderate to severe mitral valve regurgitation (MR) continues is still a high prevalence condition with bad prognosis, particularly among the elderly with left ventricular dysfunction and multiple comorbidities, at high surgical risk and therefore limited surgical indication. In this context, transcatheter mitral valve replacement (TMVR) has surged as therapeutic alternative for a carefully selected subgroup of patients deemed unsuitable for surgery or percutaneous edge-to-edge repair. However, the available evidence on its long term performance remains limited. 

Tang et al. have contributed with 5-year clinical and echocardiographic followup data on the first-generation self-expanding transapical Intrepid system (Medtronic). This prospective multicenter single-arm pilot study included 95 patients treated between 2015 and 2019 in 21 centers across Australia, Europe and US.  

The population had a very high risk profile: mean age 74, 43% women, with mean STS 6.5%, 88.4% in functional class III or IV and over 50% had been hospitalized for cardiac failure at least once within the 12 months prior procedure. MR etiology was predominantly secondary (78.7%).

Device implantation was successful in 96.8% of cases. However, the periprocedural period was associated with a non-negligible rate of early adverse events, probably linked to both the transapical approach (35 Fr catheter) and the clinical frailty of the treated population. At 30 days, mortality reached 18.9%, mostly cardiovascular, with major bleeding events mainly related to the transapical access site.

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During long term followup, 5-year cumulative cardiovascular mortality resulted 51.6%, while CF hospitalization rate reached 55.4%. However, we should highlight the fact that, among the surviving patients, valve performance remained stable over time. MR reduction was sustained, with 100% of patients presenting ≤ mild MR and no significant paravalvular leak. Mean transmitral gradient remained low and stable, at mean 3.6 mmHg, and only one case of valve moderate hemodynamic valve deterioration was documented (1.4%), with no evidence of severe deterioration.

Likewise, there was sustained functional improvement, with 84.6% of surviving patients in NYHA class I–II after 5 years. Late device-related complications were infrequent, with a low rate of clinically significant valve thrombosis in most cases associated to inadequate anticoagulation. Prosthesis endocarditis was rare and there were no cases of valve reintervention beyond the first month. 

Conclusions

The 5-year followup of the first generation Intrepid transapical system has shown that TMVR can offer sustained reduction of mitral regurgitation, with excellent hemodynamic performance and lasting functional improvement in patients overcoming the periprocedural period. The observed high mortality mainly reflects baseline complexity and severity, rather than device intrinsic limitations. At present, newer generations are being assessed, especially with a transfemoral approach, in the context of the APOLLO and APOLLO-EU trials. 

Original Title: Five-Year Outcomes of the Early-Generation Intrepid Transapical Transcatheter Mitral Valve Replacement System.

Reference: Tang GHL, Rajagopal V, Sorajja P, Bajwa T, Gooley R, Walton A, Modine T, Ng MK, Williams MR, Zajarias A, Hildick-Smith D, Tchétché D, Spargias K, Rajani R, Bapat VN, De Backer O, Blackman D, McCarthy P, Laine M, Jain R, Martin R, Thaden JJ, Marka NA, Mack M, Adams DH, Leon MB, Reardon MJ. Five-Year Outcomes of the Early-Generation Intrepid Transapical Transcatheter Mitral Valve Replacement System. EuroIntervention. 2025 Nov 16:EIJ-D-25-01133. doi: 10.4244/EIJ-D-25-01133. Epub ahead of print. PMID: 41251714.