[Selection of the prosthesis for aortic valve replacement: mechanical or bio?]

Area of Science:

• Cardiovascular Surgery
• Biomaterials Science
• Clinical Outcomes Research

Background:

• Aortic valve replacement (AVR) is a critical procedure for managing aortic valve disease.
• The choice between mechanical and bioprosthetic valves impacts long-term patient prognosis.
• Understanding comparative outcomes is essential for optimizing patient care.

Purpose of the Study:

• To investigate the long-term effects of mechanical versus bioprosthetic valve selection on patient prognosis after isolated AVR.
• To compare outcomes in all AVR patients and a specific age cohort (50-65 years).

Main Methods:

• Retrospective analysis of 472 patients undergoing isolated AVR (1975-2004), divided into mechanical (Group M) and bioprosthetic (Group B) groups.
• A secondary analysis compared 184 primary AVR patients aged 50-65.
• Outcomes assessed included freedom from cardiac death, bleeding, endocarditis, thromboembolism, and need for re-do AVR.

Main Results:

• No significant differences were observed in freedom from cardiac death, bleeding, or endocarditis between groups.
• Mechanical valves (Group M) required significantly fewer re-do AVRs in both protocols.
• Group M showed significantly worse freedom from thromboembolism in the 50-65 age group (Protocol 2).
• When re-do AVRs were included, mechanical valves demonstrated superior freedom from valve-related events.
• Excluding re-do AVRs, no significant difference in valve-related events was found between the groups.

Conclusions:

• Mechanical valves reduce the need for re-do AVR but carry a higher risk of thromboembolism, particularly in older patients.
• Bioprosthetic valves may offer an advantage for younger adults requiring AVR, provided they accept the likelihood of future re-do procedures.
• Valve selection should be individualized based on patient age, risk factors, and willingness to undergo re-intervention.