KENJI YAMAZAKI
   Department   School of Medicine(Tokyo Women's Medical University Hospital), School of Medicine
   Position   Visiting Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Left heart pressures can be the key to know the limitation of left ventricular assist device support against progression of aortic insufficiency.
Journal Formal name:Journal of Artificial Organs
Abbreviation:J Artif Organs
ISSN code:1434-7229/1619-0904
Domestic / ForeginDomestic
Publisher The Japanese Society for Artificial Organs
Volume, Issue, Page 21(3),pp.265-270
Author and coauthor IIZUKA Kei†, NISHINAKA Tomohiro, NAITO Noritsugu, AKIYAMA Daichi, TAKEWA Yoshiaki, YAMAZAKI Kenji, TATSUMI Eisuke
Publication date 2018/07
Summary Aortic insufficiency (AI) is a worrisome complication under left ventricular assist device (LVAD) support. AI progression causes LVAD-left ventricular (LV) recirculation and can require surgical intervention to the aortic valve. However, the limitations of LVAD support are not well known. Using an animal model of LVAD with AI, the effect of AI progression on hemodynamics and myocardial oxygen metabolism were investigated. Five goats (Saanen 48 ± 2 kg) underwent centrifugal type LVAD, EVAHEART, implantation. The AI model was established by placing a vena cava filter in the aortic valve. Cardiac dysfunction was induced by continuous beta-blockade (esmolol) infusion. Hemodynamic values and myocardial oxygen extraction ratio (O2ER) were evaluated while changing the degree of AI which was expressed as the flow rate of LVAD-LV recirculation (recirculation rate). Diastolic aortic pressure was decreased with AI progression and correlated negatively with the recirculation rate (p = 0.00055). Systolic left ventricular pressure (LVP) and mean left atrial pressure (LAP) were increased with AI progression and correlated positively with the recirculation rate (p = 0.010, 0.023, respectively). LVP and LAP showed marked exponential increases when the recirculation rate surpassed 40%. O2ER was also increased with AI progression and had a significant positive correlation with the recirculation rate (p = 0.000043). O2ER was increased linearly, with no exponential increase. AI progression made it difficult to reduce the cardiac pressure load, worsening myocardial oxygen metabolism. The exponential increase of left heart pressures could be the key to know the limitation of LVAD support against AI progression.
DOI 10.1007/s10047-018-1027-4
PMID 29464441