Abstract
We designed a new method of pericardiomyoplasty using a rectus abdominis pedicled graft, to assist biventricular function. Eight mongrel dogs (weight 12-18 Kg, mean 14 Kg) were used in this study with and without production of heart failure. Unconditioned left rectus muscle (2.5g/Kg BW) were dissected as a pedicle with an intact internal thoracic artery and vein following a median sternotomy. Then the anterior half of the pericardium was replaced with a rectus abdominis pedicled graft. Three denervated intercostal nerves on the rectus muscle were simultaneously paced by 1:3 synchronous mode using burst stimulation (50Hz, 6v). Acute heart failure model in all dogs were produced by infusion of 2mg/Kg propranolol associated with volume loading. Stimulation by pericardiomyoplasty significantly increased in peak aortic pressure(AoP), peak right ventricular pressure (RVP), and descending aortic stroke flow (AoF) by 8.6%, 53.6%, and 18.1% respectively. After induction of acute heart failure AoP, RVP, and AoF were more pronouncedly augmented by this stimulation. This study suggests that the rectus abdominis is applicable for biventricular assistance despite small amount of muscle volume
