Long-Term Outcomes of Valve Replacement With Mechanical Prosthesis in Patients With Valvular Heart Disease: A Single-Center Retrospective Study

Abstract

Background Significant valve disease requires surgical intervention, either valve repair or valve replacement. For minor disease, balloon dilation is a possibility. The choice between mechanical and bioprosthetic valves requires a judgment regarding the benefits and risks of each procedure. A mechanical prosthetic valve requires lifelong anticoagulation, whereas a bioprosthetic valve tends to degenerate over a few years, with faster degeneration observed in younger patients. Objective To assess the survival outcomes, postoperative complications, and reoperation rates in patients who underwent prosthetic mechanical valve replacement with acenocoumarol and low-dose aspirin (75 mg), with adequate International Normalized Ratio (INR) monitoring. Methods and materials This was a retrospective study involving data from patients who underwent mechanical cardiac valve replacement between 1971 and 2022. This study adhered to the principles outlined in the Declaration of Helsinki and received approval from the institutional ethics review board of Bombay Hospital (Regn. No: ECR/296/Inst/MH/2013; Date: 08/12/2021). Results A total of 768 patients were included. The mean overall survival rate was 35.2%, and it was higher in men than in women. The majority of patients belonged to a younger age group (≤18 years: 6.3%, 19-40 years: 47.7%, 41-60 years: 42.2%, >60 years: 3.9%). The mean overall survival rate was higher in men (37.4%) than in women (28.4%). In the first year post-surgery, females experienced Major Adverse Cardiac and Cerebrovascular Events (MACCE) at a rate of 11.1 person-years, while males had none. Among patients classified as New York Heart Association (NYHA) class III, the incidence rate of MACCE was 2.7 person-years, whereas for NYHA class IV patients, it was 8.3 person-years. These trends persisted to some extent at the fifth year post-surgery. Conclusion Survival outcomes were influenced by factors such as age, sex, type of valve replacement, and NYHA class, with certain subgroups showing better survival rates. The first year post-surgery presented a higher incidence of MACCE, which declined over time. Mechanical valve replacement with appropriate anticoagulation can offer favorable long-term outcomes, particularly in younger patients. However, early postoperative risks, especially in women and those with advanced heart failure, highlight the need for individualized care and close monitoring. Future research should aim to refine patient selection, explore sex-based outcome disparities, and optimize anticoagulation strategies to further improve survival and quality of life in this population.

Keywords: major adverse cardiovascular events; mechanical valve; rheumatic heart disease; survival rate; valvular heart disease.

Figure 1. Survival of patients at risk by gender distribution.

Figure 2. Survival of patients by type of valve used.

Figure 3. Survival of patients at risk by NYHA classification.

NYHA: New York Heart Association.

Figure 4. Survival of patients at risk by type of valve combination.

Figure 5. Survival of patients at risk by type of prosthetic valve.

Figure 6. Forest plot of HRs (95% CIs) representing multivariate analysis of long-term survival.

Figure 7. Relative distribution of TTR control groups.

Poor control: TTR ≤ 50%; Intermediate control: TTR 50.1%-70.0%; Good control: TTR > 70%. TTR: Time to therapeutic range.