title: The effect of left ventricular function and drive pressures on the filling and ejection of a pulsatile pediatric ventricular assist device in an acute animal model.
abstract: Penn State is currently developing a 12-mL, pulsatile, pneumatically driven pediatric ventricular assist device intended to be used in infants. After extensive in vitro testing of the pump in a passive-filling, mock circulatory loop, an acute animal study was performed to obtain data with a contracting ventricle. The objectives were to determine the range of pneumatic pressures and time required to completely fill and empty the pediatric ventricular assist device under various physiologic conditions, simulate reductions in ventricular contractility and blood volume, and provide data for validation of the mock circulatory loop. A 15-kg goat was used. The cannulation was achieved via left thoracotomy from the left ventricle to the descending aorta. The pump rate and systolic duration were controlled manually to maintain complete filling and ejection. The mean ejection time ranged from 280 ms to 382 ms when the systolic pressure ranged from 350 mm Hg to 200 mm Hg. The mean filling time ranged from 352 ms to 490 ms, for the diastolic pressure range of -60 mm Hg to 0 mm Hg. Esmolol produced a decrease in left ventricular pressure, required longer pump filling time, and reduced LVAD flow.
authors.affiliation: Department of Surgery, Penn State Milton S. Hershey Medical Center, Penn State College of Medicine, Penn State Children's Hospital, Hershey, Pennsylvania 17033, USA.
authors.forename: Branka
authors.initials: B
authors.lastname: Lukic
authors.forename: Conrad M
authors.initials: CM
authors.lastname: Zapanta
authors.forename: Tigran
authors.initials: T
authors.lastname: Khalapyan
authors.forename: John
authors.initials: J
authors.lastname: Connell
authors.forename: Walter E
authors.initials: WE
authors.lastname: Pae
authors.forename: John L
authors.initials: JL
authors.lastname: Myers
authors.forename: Ronald P
authors.initials: RP
authors.lastname: Wilson
authors.forename: Akif
authors.initials: A
authors.lastname: Undar
authors.forename: Gerson
authors.initials: G
authors.lastname: Rosenberg
authors.forename: William J
authors.initials: WJ
authors.lastname: Weiss
mesh_terms: D000208:Acute Disease; D000319:Adrenergic beta-Antagonists; D000818:Animals; D001794:Blood Pressure; D015924:Blood Pressure Monitors; D001810:Blood Volume; D002303:Cardiac Output, Low / Q000139:chemically induced / Q000601:surgery*; D004195:Disease Models, Animal; D005260:Female; D006041:Goats; D006353:Heart-Assist Devices; D006801:Humans; D007223:Infant; D008955:Models, Cardiovascular; D011412:Propanolamines; D011673:Pulsatile Flow; D013318:Stroke Volume; D013908:Thoracotomy
chemical_list: D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; C036604:esmolol