title: Hemodynamic changes and retrograde flow in LVAD failure.
abstract: In the event of left ventricular assist device (LVAD) failure, we hypothesized that rotary blood pumps will experience significant retrograde flow and induce adverse physiologic responses. Catastrophic LVAD failure was investigated in computer simulation with pulsatile, axial, and centrifugal LVAD, mock flow loop with pulsatile (PVAD) and centrifugal (ROTAFLOW), and healthy and chronic ischemic heart failure bovine models with pulsatile (PVAD), axial (HeartMate II), and centrifugal (HVAD) pumps. Simulated conditions were LVAD "off" with outflow graft clamped (baseline), LVAD "off" with outflow graft unclamped (LVAD failure), and LVAD "on" (5 L/min). Hemodynamics (aortic and ventricular blood pressures, LVAD flow, and left ventricular volume), echocardiography (cardiac volumes), and end-organ perfusion (regional blood flow microspheres) were measured and analyzed. Retrograde flow was observed with axial and centrifugal rotary pumps during LVAD failure in computer simulation (axial = -3.4 L/min, centrifugal = -2.8 L/min), mock circulation (pulsatile = -0.1 L/min, centrifugal = -2.7 L/min), healthy (pulsatile = -1.2 ± 0.3 L/min, axial = -2.2 ± 0.2 L/min, centrifugal = -1.9 ± 0.3 L/min), and ischemic heart failure (centrifugal = 2.2 ± 0.7 L/min) bovine models for all test conditions (p < 0.05). Differences between axial and centrifugal LVAD were statistically indiscernible. Retrograde flow increased ventricular end-systolic and end-diastolic volumes and workload, and decreased myocardial and end-organ perfusion during LVAD failure compared with baseline, LVAD support, and pulsatile LVAD failure.
authors: From the *Department of Bioengineering, Cardiovascular Innovation Institute, University of Louisville, Louisville, Kentucky 40292; †Department of Cardiovascular and Thoracic Surgery, Cardiovascular Innovation Institute, University of Louisville, Louisville, Kentucky 40202; ‡Eidgenössische Technische Hochschule Hönggerberg, Zürich, Switzerland; and §Division of Cardiovascular Surgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania 19104.
authors: Guruprasad A
authors: GA
authors: Giridharan
authors: Steven C
authors: SC
authors: Koenig
authors: Kevin G
authors: KG
authors: Soucy
authors: Young
authors: Y
authors: Choi
authors: Tohid
authors: T
authors: Pirbodaghi
authors: Carlo R
authors: CR
authors: Bartoli
authors: Gretel
authors: G
authors: Monreal
authors: Michael A
authors: MA
authors: Sobieski
authors: Erin
authors: E
authors: Schumer
authors: Allen
authors: A
authors: Cheng
authors: Mark S
authors: MS
authors: Slaughter
mesh_terms: D000818:Animals; D002417:Cattle; D003198:Computer Simulation; D004195:Disease Models, Animal; D004868:Equipment Failure; D006333:Heart Failure / Q000601:surgery; D006352:Heart Ventricles; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006439:Hemodynamics; D008297:Male; D008955:Models, Cardiovascular