Design of Patient Testing Models for Cardiovascular Medical Device in Silico and In Vitro Assessment

Abstract

Clinical evidence indicates that left ventricular assist device (LVAD) recipients present a diverse cohort of pathophysiology and cardiac functionality. The challenge of assuring device safety and proper performance in this patient set represents a challenge in both the range and resolution of the conditions. Furthermore, the cardiovascular systems of these individuals are highly susceptible to events that may trigger unsafe operating conditions for the LVAD: sudden postural change (e.g falling), drug induced tachycardia, etc. Developing appropriate computational design tools and reflective in vitro test system permits device designers to elucidate more liabilities in the design earlier in the development cycle. Conditions for a mock circulatory loop were sourced from clinical publications detailing the cardiovascular parameters determined for various patient classes and event sequences. The developed profiles for healthy adult, congestive heart failure adult, healthy geriatric, congestive heart failure geriatric, and healthy pediatric were designed. The profiles were developed from published clinical metrics and parameter estimations of PhysioBank data. How the profiles were constructed, as well as simulation and parameter estimation techniques will be discussed. As the profile of the patients receiving these devices diversifies, it becomes necessary to update the tools used in the V&V structure used to properly assess these new devices. The aforementioned mock circulatory loop, and accompanying computational model, deliver the combined V&V toolset needed to address this new range of questions on safety assurance for a widening scope of use for these devices.