Fifteen-year experience with the Bicarbon heart valve prosthesis in a single center

Comparative Long-Term Clinical Performance of Mechanical Aortic Valve Prostheses

Importance

Aggregated data and long-term follow-up in national health data registers offer the opportunity to compare the performance of mechanical aortic prostheses within the same population.

Objective

To investigate the clinical performance of mechanical aortic valve prostheses.

Design, Setting, and Participants

This nationwide cohort study included all 5224 patients who underwent primary mechanical aortic valve replacement in Sweden between January 1, 2003, and December 31, 2018. Statistical analysis was performed between May and September 2023.

Exposures

Surgical aortic valve replacement with the On-X, Carbomedics, Bicarbon, Standard, Regent, Open Pivot, Masters, or Advantage valve models.

Main Outcomes and Measures

The primary outcome was all-cause mortality, and secondary outcomes were reintervention, heart failure, major bleeding, stroke, and embolic events. Regression standardization was used to account for baseline differences.

Results

Overall, 5224 patients (mean [SD] age, 56.8 [11.7] years; 3908 men [74.8%]) were included. Total follow-up time was 43 982 person-years (mean [SD], 8.4 [4.6] years; maximum, 17.2 years). After regression standardization, there was a significant difference in 10-year mortality between the Carbomedics model group (17%; 95% CI, 15%-18%), Regent model group (17%; 95% CI, 13%-20%), and Standard model group (17%; 95% CI, 14%-19%) compared with the Bicarbon model group (27%; 95% CI, 21%-34%).

Conclusions and Relevance

In this cohort study of mechanical valve surgical aortic replacement outcomes in Sweden, the rate of all-cause mortality was higher in the Bicarbon group than in the Carbomedics, Regent, and Standard model groups. These findings warrant further research on the long-term clinical performance of the Bicarbon valve.

Early Hemodynamic Profile after Aortic Valve Replacement - A Comparison between Three Mechanical Valves

INTRODUCTION

There are scarce data comparing different mechanical valves in the aortic position. The objective of this study was to compare the early hemodynamic changes after aortic valve replacement between ATS, Bicarbon, and On-X mechanical valves.

METHODS

We included 99 patients who underwent aortic valve replacement with mechanical valves between 2017 and 2019. Three types of mechanical valves were used, On-X valve (n=45), ATS AP360 (n=32), and Bicarbon (n=22). The mean prosthetic valve gradient was measured postoperatively and after six months.

RESULTS

Preoperative data were comparable between groups, and there were no differences in preoperative echocardiographic data. Pre-discharge echocardiography showed no difference between groups in the ejection fraction (P=0.748), end-systolic (P=0.764) and end-diastolic (P=0.723) diameters, left ventricular mass index (P=0.348), aortic prosthetic mean pressure gradient (P=0.454), and indexed aortic prosthetic orifice area (P=0.576). There was no difference in the postoperative aortic prosthetic mean pressure gradient between groups when stratified by valve size. The changes in the aortic prosthetic mean pressure gradient of the intraoperative period, at pre-discharge, and at six months were comparable between the three prostheses (P=0.08). Multivariable regression analysis revealed that female gender (beta coefficient -0.242, P=0.027), body surface area (beta coefficient 0.334, P<0.001), and aortic prosthetic size (beta coefficient -0.547, P<0.001), but not the prosthesis type, were independent predictors of postoperative aortic prosthetic mean pressure gradient.

CONCLUSION

The three bileaflet mechanical aortic prostheses (On-X, Bicarbon, and ATS) provide satisfactory early hemodynamics, which are comparable between the three valve types and among different valve sizes.

Nineteen Years of Single Institute Experiences with Sorin Bicarbon Prosthesis

Purpose: We want to share our experience of Sorin Bicarbon prosthesis (SBP) after 19 years follow-up.

Methods: Retrospective study of 1377 patients who had replaced with SBP from May 1998 to December 2008 at Ho Chi Minh Heart Institute, Viet Nam.

Results: Male patients was 42%, mean age was 40.2 ± 11.8 years. Atrial fibrillation was 43.5%. The main cause of valvular disease was rheumatic fever (89.8%). Isolated mitral valve replacement (MVR): 54% (744), isolated aortic valve replacement (AVR): 18% (247), double valve replacement (DVR): 26% (359), and 27 AVR plus mitral repair. 30-day mortality for all was 1.5%. Mean time of follow-up was 153 ± 53.1 months with total follow-up time was 17563 patients-years. 2.5% lost of follow-up. Late death was 77 cases. Redo for all causes was 59 cases. 19 years survival was 88.8 ± 1.8%. 19 years freedom of redo was 76.4 ± 4.7%. Linearized rate of all valve thrombosis, embolism, severe bleeding, endocarditis, and pannus were 0.31%, 0.28%, 0.267%, 0.068%, and 0.165% patient-years, respectively.

Conclusions: SBP had shown very good results in long term and still have a reliable mechanical valve.

Low-dose anticoagulation after isolated mechanical aortic valve replacement with Liva Nova Bicarbon prosthesis: A post hoc analysis of LOWERING-IT Trial

Thromboembolic complications after cardiac valve replacement are due to a complex interplay between patients' characteristics, device features and anticoagulation intensity. Subtle design and material differences in available prostheses may thrombosis. We conducted a post-hoc sub-analysis of the LOWERING-IT database to test the safety and feasibility of a low-level oral anticoagulant regime in low-risk patients with aortic LivaNova prosthetic valve replacement. The study population included 148 patients randomized to a low INR target (1.5-2.5; LOW-INR group), and 144 patients to the standard INR (2.0-3.0; CONVENTIONAL-INR group). The non-inferiority of thromboembolic events between LOW-INR and CONVENTIONAL-INR groups was tested. Cumulative follow-up reached 1,545 patient/years. The mean INR was 1.91 ± 0.23 in the LOW-INR group, and 2.59 ± 0.26 in the CONVENTIONAL-INR group (P < 0.001). There were 3 thromboembolic events, all in the CONVENTIONAL-INR group. Comparison of thromboembolic events was not significant. The 1-sided 97.5% exact CI for the difference in primary event proportion was 0.54%, satisfying criteria non-inferiority. Bleeding events were significantly different: 6.61 per 1,000 patient-year in LOW-INR group vs 18.65 per 1,000 patient-year in CONVENTIONAL-INR group (p < 0.045, RR 0.37). In conclusions these data suggest that low-dose anticoagulation is safe in selected patients after aortic LivaNova Bicarbon prosthesis implantation.