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Mechanism of Self‐Regulation and In Vivo Performance of the Cleveland Clinic Continuous‐Flow Total Artificial Heart
Author(s) -
Horvath David,
Byram Nicole,
Karimov Jamshid H.,
Kuban Barry,
Sunagawa Gengo,
Golding Leonard A.R.,
Moazami Nader,
Fukamachi Kiyotaka
Publication year - 2017
Publication title -
artificial organs
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.684
H-Index - 76
eISSN - 1525-1594
pISSN - 0160-564X
DOI - 10.1111/aor.12780
Subject(s) - artificial heart , mechanism (biology) , continuous flow , medicine , engineering , cardiology , biochemical engineering , philosophy , epistemology
Cleveland Clinic's continuous‐flow total artificial heart (CFTAH) provides systemic and pulmonary circulations using one assembly (one motor, two impellers). The right pump hydraulic output to the pulmonary circulation is self‐regulated by the rotating assembly's passive axial movement in response to atrial differential pressure to balance itself to the left pump output. This combination of features integrates a biocompatible, pressure‐balancing regulator with a double‐ended pump. The CFTAH requires no flow or pressure sensors. The only control parameter is pump speed, modulated at programmable rates (60–120 beats/min) and amplitudes (0 to ±25%) to provide flow pulses. In bench studies, passive self‐regulation (range: −5 mm Hg ≤ [left atrial pressure – right atrial pressure] ≤ 10 mm Hg) was demonstrated over a systemic/vascular resistance ratio range of 2.0–20 and a flow range of 3–9 L/min. Performance of the most recent pump configuration was demonstrated in chronic studies, including three consecutive long‐term experiments (30, 90, and 90 days). These experiments were performed at a constant postoperative mean speed with a ±15% speed modulation, demonstrating a totally self‐regulating mode of operation, from 3 days after implant to explant, despite a weight gain of up to 40%. The mechanism of self‐regulation functioned properly, continuously throughout the chronic in vivo experiments, demonstrating the performance goals.