COMPUTATIONAL MODELING AND ANALYSIS OF HEMODYNAMIC EFFECTS OF DIASTOLIC HEART DYSFUNCTION DURING THE WHOLE CARDIAC CYCLE

摘要

Diastolic heart dysfunction (DHD) is a common finding in a variety of cardiac diseases including hypertension, coronary disease and cardiomyopathy. Its prevalence increases with age and it manifests as incomplete or/and delayed ventricular relaxation and a compensatory stronger atrial contraction. DHD is often associated with heart failure and contributes greatly to morbidity and hospitalizations especially in the elderly[3]. DHD is a very rich problem in fluid mechanics and it involves complex hemodynamic interactions among all of major cardiac phases during the whole cardiac cycle including ventricular filling, diastatsis, atrial filling, and systole[1]. Most studies to-date have, however, employed simple time varying volume-change profiles to model and examine the dynamics of ventricular filling[2]. Intercardiac flow effects i.e. interaction between filling and ejection have, however, not been investigated in detail. Also not studied in detail is the role of multiphasic filling which consists of early (E) filling, diastasis, and atrial (A) filling. In the current study, we will utilize three dimensional simulations to study the hemodynamics of DHD during the whole cardiac cycle. The vortex structure, filling velocity, intraventricular pressure gradient and energy budget will be analyzed to uncover the biomechanical effects and genesis of DHD.