Mechanical or biologic prostheses for mitral valve replacement: A systematic review and meta-analysis

Area of Science:

• Cardiovascular Surgery
• Medical Technology
• Clinical Outcomes Research

Background:

• Mitral valve replacement (MVR) utilizes either mechanical or bioprosthetic valves.
• The choice between mechanical mitral valve replacement (MVRm) and bioprosthetic mitral valve replacement (MVRb) remains a subject of debate.
• Optimal prosthesis selection is critical for patient outcomes following MVR.

Purpose of the Study:

• To conduct a meta-analysis comparing outcomes between MVRm and MVRb.
• To evaluate long-term mortality, reoperation rates, bleeding events, and thromboembolic complications.
• To provide evidence-based guidance for mitral valve prosthesis selection.

Main Methods:

• Systematic literature search of Embase, PubMed, Web of Science, and Cochrane Library databases (2000-2021).
• Inclusion of 22 studies with 35,903 patients (23,868 MVRm, 12,035 MVRb).
• Meta-analysis of matched or adjusted data to compare surgical outcomes.

Main Results:

• MVRm group showed significantly lower long-term all-cause mortality (HR 0.84) and mitral reoperation rates (HR 0.34) compared to MVRb.
• MVRm was associated with a higher risk of major bleeding events (HR 1.21) and stroke/systemic embolism (HR 1.20).
• No significant difference in operative mortality was observed between MVRm and MVRb groups.

Conclusions:

• MVRm is associated with reduced long-term mortality and reoperation risk but increased bleeding and thromboembolic event risk.
• These findings were consistent in patients younger than 70 years.
• The study provides crucial data for informed decision-making in mitral valve replacement strategies.