In-Vitro Pulsatile Flow Testing of Prosthetic Heart Valves: A Round-Robin Study by the ISO Cardiac Valves Working...

Area of Science:

• Biomedical Engineering
• Medical Device Testing
• Cardiovascular Research

Background:

• Hydrodynamic performance testing is crucial for prosthetic heart valves per ISO 5840 standards.
• A 2005 round-robin study revealed significant inter-laboratory variability in these measurements.
• This variability necessitates re-evaluation of current testing protocols.

Purpose of the Study:

• To re-examine inter-laboratory variability in prosthetic heart valve hydrodynamic performance testing.
• To assess the state-of-the-art under the latest ISO 5840-1 and 5840-2:2015 standards.
• To identify areas for improvement in in vitro assessment procedures.

Main Methods:

• A 2016 round-robin study involving 13 international laboratories.
• Testing of St. Jude Medical Masters Series mechanical valves across various sizes.
• Standardized testing procedures with prespecified flow conditions.

Main Results:

• Improved, yet still significant, inter-laboratory variability was observed compared to the 2005 study.
• Coefficients of variation ranged from 7.7% to 21.6% for effective orifice area.
• Variability was also significant for regurgitant fraction (10.1-32.8%) and pressure gradient (14.7-45.5%).

Conclusions:

• The study identified ambiguities in current ISO 5840 standards and laboratory shortcomings.
• Clarifications are being incorporated into revised ISO 5840-1, -2, and -3 standards.
• Results can guide laboratories in benchmarking equipment and personnel training for in vitro assessments.