Early outcomes of transapical mitral valve implantation versus surgical replacement in matched elderly patients at intermediate surgical risk.

BACKGROUND: Data comparing transcatheter mitral valve implantation (TMVI) with surgical mitral valve replacement (SMVR) are lacking. AIMS: This study sought to compare the 30-day Valve Academic Research Consortium (VARC)-3 device success of TMVI with that of SMVR. METHODS: Matching protocol combined exact matching (sex, atrial fibrillation, previous surgical aortic valve replacement [SAVR] or coronary artery bypass grafting [CABG]), coarsened exact matching (age) and propensity score matching (body mass index, mitral valve pathology and concomitant tricuspid regurgitation). RESULTS: A total of 40 Tendyne TMVI and 80 SMVR patients with similar baseline characteristics were analysed (TMVI vs SMVR): age (78 years [interquartile range [{IQR} 75; 80] vs 78 years [IQR 73; 80]; p=0.8), female (60% vs 60%; p=1.0), atrial fibrillation (67.5% vs 63.7%; p=0.8), previous SAVR (12.5% vs 10.0%; p=0.8), previous CABG (20.0% vs 16.2%; p=0.8), body mass index (25.54 kg/m² vs 25.24 kg/m²; p=0.7) and valve pathology (mitral regurgitation: 70.0% vs 73.8%, mitral stenosis: 7.5% vs 3.8%, and mixed disease: 22.5% vs 22.5%; p=0.6). Most baseline characteristics not included in the matching model were balanced among the TMVI/SMVR cohorts: European System for Cardiac Operative Risk Evaluation (EuroSCORE) II (5.8% [IQR 2.9; 7.5] vs 4.2% [IQR 2.4; 6.8]; p=0.3) and Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score (5.2% [IQR 3.2; 8.6] vs 4.1% [IQR 3.3; 6.1]; p=0.076). Coronary artery disease (67.5% vs 32.5%; p<0.001) and previous percutaneous coronary intervention (47.5% vs 25.0%; p=0.023) differed among groups. Mitral VARC (MVARC) device success at 30 days was achieved in 82.5% of patients after TMVI and 57.5% of patients after SMVR (p=0.04). MVARC procedural success at 30 days was 75.0% after TMVI versus 52.5% after SMVR (p=0.07). Thirty-day mortality (2.5% vs 3.8%; p=0.47), technical success (97.5% vs 97.5%; p=1.0), major bleeding (17.5% vs 18.7%; p=0.087), stroke (5.0% vs 4.9%; p=1.0) and postoperative haemodialysis (7.5% vs 5.2%; p=0.4) were similar in both groups. CONCLUSIONS: Patients with intermediate surgical risk, according to STS-PROM and EuroSCORE II, demonstrated higher rates of MVARC device at 30 days after TMVI compared to 30 days after SMVR. Rates of survival and procedural success, neurological, renal and bleeding complications were similar. Transfusion count and length of stay were lower after TMVI. For elderly patients at intermediate risk, a TMVI eligibility assessment may be considered.

Optical monitoring during bioreactor conditioning of tissue-engineered heart valves.

Currently, one approach to tissue engineering has been to develop in vitro conditions to fabricate functional cardiovascular structures such as heart valves before final implantation. In vivo conditions are simulated using a bioreactor system that supplies cells with oxygen and culture media while providing mechanical stimulation to promote tissue maturation. In our experiment, we developed a novel combined optical monitoring and conditioning device. The entire system is made of acrylic glass and is completely transparent. The bioreactor is connected to an air-driven respirator pump, and the cell culture medium continuously circulates through a closed-loop system. By adjusting stroke volume, stroke rate, and inspiration/expiration time of the ventilator, the system allows various pulsatile flows and different levels of pressure. Our optical monitoring and conditioning device provides a sterile environment, mechanical stimulation, and optical monitoring for the in vitro maturation of a tissue-engineered heart valve. With the camera module attached, tissue-engineered valves can be observed during the entire in vitro phase. This setting helps to find the optimal dynamic conditions for tissue-engineered heart valves to mature by adjusting flow and pressure conditions to provide physiological opening and closing behavior of the heart valve construct.