The Effect of Impeller Position on CFD Calculations of Blood Flow in Magnetically Levitated Centrifugal Blood Pumps

Cardiovascular disease is the leading cause of mortality globally. Among various forms of cardiovascular disease, heart failure (HF) affects 5.7 million patients in the United States with about 670,000 new patients diagnosed for the first time annually (1). The fatality rate for HF is high, with one in five people dying within 1 year (1). The number of deaths has increased (1) despite advances in surgical treatment and new pharmaceutical therapies. Many therapies are available to treat patients with HF, including lifestyle changes, medications, transcatheter interventions and surgery. However, despite optimal medical and surgical therapies, some patients still do not improve and the available therapies fail to control their symptoms; for them, cardiac transplantation may be the only treatment option. However, only approximately 2300 donor hearts become available each year resulting in around 2200 transplants (1), or only about 6% of the estimated 35,000 US patients who would benefit from a heart actually receiving a transplant. To address the need to support the circulation in patients with end-stage HF a wide variety of mechanical circulatory support devices (MCSDs) have been developed over the past four decades. These MCSDs have been developed as a bridge to transplant, a bridge to recovery, and as an end stage treatment. They can be implanted as a ventricular assist device (VAD) to support the left ventricle (LVAD) or the right ventricle (RVAD) or two devices are used to support both left and right ventricles (Bi-VAD).