Ionescu-Shiley valve failure. II: Experience with 25 low-profile explants

Area of Science:

• Cardiovascular Surgery
• Biomaterials Science
• Medical Device Engineering

Background:

• The Ionescu-Shiley valve is a bioprosthetic cardiac valve used in aortic and mitral positions.
• Bioprosthetic valve failure, particularly cusp tears leading to insufficiency, is a significant clinical concern.
• Understanding failure modes is crucial for improving long-term device performance and patient outcomes.

Purpose of the Study:

• To investigate the explantation reasons and failure patterns of low-profile Ionescu-Shiley valves.
• To compare the failure characteristics of low-profile valves with standard-profile Ionescu-Shiley valves.
• To identify potential implications for future bioprosthetic valve design.

Main Methods:

• Retrospective review of patients with explanted low-profile Ionescu-Shiley valves (237 aortic, 130 mitral).
• Analysis of explantation reasons, focusing on cusp tears and valvular insufficiency.
• Morphologic examination of explanted valves.
• Comparison of failure data with historical data from standard-profile Ionescu-Shiley valves.

Main Results:

• Valvular insufficiency due to cusp tears was the primary reason for explantation (50% aortic, 82% mitral).
• Low-profile valves failed significantly sooner than standard-profile valves (mean 45.1 vs. 78.0 months in aortic; 52.2 vs. 73.8 months in mitral).
• Mitral valve failures due to tears were proportionally more common in the low-profile group compared to the standard-profile group.

Conclusions:

• Low-profile Ionescu-Shiley valves exhibit distinct failure patterns, primarily cusp tears, with a higher incidence in the mitral position.
• These valves demonstrate a shorter in situ lifespan compared to their standard-profile counterparts.
• Findings suggest a need for design modifications in future bioprosthetic valves to enhance durability and longevity.