Structural valve deterioration in a starr-edwards mitral caged-disk valve prosthesis

Area of Science:

• Cardiovascular Surgery
• Biomaterials Science
• Medical Device Engineering

Background:

• The long-term durability of the Starr-Edwards (SE) mitral caged-disk valve, model 6520, remains incompletely understood.
• Structural valve deterioration (SVD) is considered rare for this specific mechanical heart valve model.

Purpose of the Study:

• To investigate the long-term structural integrity and potential deterioration of the SE mitral caged-disk valve.
• To determine the in-vivo performance and failure modes of SE mitral valves after extended implantation periods.

Main Methods:

• Analysis of explanted SE mitral disk valves (model 6520) from 7 patients.
• Macroscopic examination of valves removed between 23 and 40 years post-implantation.
• Assessment of structural abnormalities, disk wear, and disk fracture.

Main Results:

• No structural abnormalities were found in valves explanted before 26 years.
• Localized disk wear was observed in valves implanted for over 36 years.
• Disk fracture and multiple cracks were detected in valves implanted for 36 and 40 years.

Conclusions:

• Significant structural deterioration, including disk fracture and wear, can occur in SE mitral caged-disk valves after more than 36 years.
• Mechanical mitral valves implanted for over 20 years warrant close monitoring.
• Elective replacement with modern prosthetic valves is recommended for SE mitral valves implanted for over 30 years.