Hemodynamic effects of pumpless extracorporeal membrane oxygenation (ECMO) support for chronically pressure-overloaded right heart failure in a canine experimental model.
OBJECTIVE
This study was done to evaluate the hemodynamic effects of a pumpless implantable extracorporeal membrane oxygenation (ECMO) circuit between the right ventricle (RV) and left atrium (LA) in a chronic canine model with an RV pressure overload.


METHODS
We created a model of right-sided heart failure by pulmonary artery banding in ten dogs for a duration of more than 3 months. After demonstrating that the RV pressure increased, a bypass circuit was created between the RV and LA with an in-line oxygenator. Both the hemodynamics and gas exchange were measured.


RESULTS
The effects of a pulmonary bypass in nine dogs were studied. Approximately half of the RV output was passively shunted through the bypass circuit, and a marked reduction in the RV pressure and recovery from right heart failure were observed. After a complete ligation of the main pulmonary artery, five of the nine dogs survived more than 6 h. The RV pressure did not change significantly, but the cardiac output and blood pressure gradually decreased. The blood gas state was sufficiently maintained throughout the experiment.


CONCLUSIONS
The present study indicates the hemodynamic benefit of a partial pumpless ECMO system in dogs with chronically pressure-overloaded right heart failure; however, the experimental preparation of the total pumpless ECMO circuit proved to be unstable.
Tamesue
Kiyokazu
K
Department of Cancer and Thoracic Surgery, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama, 700-0914, Japan.
Nawa
Sugato
S
Ichiba
Shingo
S
Aoe
Motoi
M
Date
Hiroshi
H
Shimizu
Nobuyoshi
N
D000818:Animals; D000831:Animals, Newborn; D001784:Blood Gas Analysis; D002908:Chronic Disease; D004195:Disease Models, Animal; D004285:Dogs; D015199:Extracorporeal Membrane Oxygenation / Q000379:methods*; D006333:Heart Failure / Q000175:diagnosis / Q000628:therapy*; D006439:Hemodynamics / Q000502:physiology*; D011312:Pressure; D011336:Probability; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D018497:Ventricular Dysfunction, Right / Q000175:diagnosis / Q000628:therapy*