Skeletal muscle ventricles in the pulmonary circulation: up to 16 weeks' experience.
Skeletal muscle ventricles (SMVs) were constructed from the right latissimus dorsi muscle of 8 mongrel dogs. After a 3-week vascular delay period, each SMV was electrically preconditioned with 2-Hz continuous stimulation of the thoracodorsal nerve for 6 weeks. A porcine-valved conduit was then anastomosed between the right ventricle and the SMV, with a second valved conduit connecting the SMV to the main pulmonary artery. The pulmonary artery was then ligated proximal to the conduit. The SMVs were stimulated to contract in 1:2 diastolic mode with a 33-Hz burst frequency. Effective right ventricular assist was achieved in all dogs. Cardiac output increased by 22.6% (1,799 +/- 97 versus 1,467 +/- 84 mL/min; p less than 0.001), systemic systolic arterial pressure by 9.3% (90.1 +/- 3.5 versus 82.4 +/- 3.9 mm Hg; p less than 0.005), and peak pulmonary artery pressure by 31.8% (27.8 +/- 2.0 versus 21.1 +/- 1.7 mm Hg; p less than 0.001) at the initiation of this study. In 6 dogs, effective right heart assist was sustained for periods of between 1 week and 12 weeks. Two dogs survived for longer than 3 months, though with evidence of deteriorating SMV function. These results demonstrate the feasibility of providing sustained right ventricular assist using this modified "Rastelli-SMV" configuration, which obviates the limitations imposed by low right atrial preload.
Niinami
H
H
Department of Surgery, Wayne State University School of Medicine, Detroit, Michigan 48201.
Hooper
T L
TL
Hammond
R L
RL
Ruggiero
R
R
Lu
H
H
Spanta
A D
AD
Pochettino
A
A
Colson
M
M
Stephenson
L W
LW
D000222:Adaptation, Physiological / Q000502:physiology*; D000714:Anastomosis, Surgical; D000818:Animals; D001243:Assisted Circulation / Q000379:methods*; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D004285:Dogs; D004558:Electric Stimulation; D009132:Muscles / Q000473:pathology / Q000502:physiology* / Q000637:transplantation*; D011651:Pulmonary Artery / Q000502:physiology / Q000601:surgery; D013318:Stroke Volume / Q000502:physiology; D016276:Ventricular Function