Jh. Stevens et al., PORT-ACCESS CORONARY-ARTERY BYPASS WITH CARDIOPLEGIC ARREST - ACUTE AND CHRONIC CANINE STUDIES, The Annals of thoracic surgery, 62(2), 1996, pp. 435-440
Background. Our goal is to perform minimally invasive coronary artery
bypass grafting without sacrificing the benefits of myocardial protect
ion with cardioplegia. Methods. Twenty-three dogs underwent acute stud
ies and 4 dogs underwent survival studies. The left internal mammary a
rtery was taken down using a thoracoscope. Cardiopulmonary bypass was
conducted via femoral cannulas and using an endovascular balloon cathe
ter for ascending aortic occlusion, root venting, and delivery of ante
grade blood cardioplegia. Pulmonary artery venting was achieved with a
jugular vein catheter. An internal mammary artery-to-coronary artery
anastomosis was performed using a microscope through a 10 mm port. Res
ults. All animals were weaned from cardiopulmonary bypass in sinus rhy
thm without inotropes. Cardiopulmonary bypass duration was 104 +/- 28
minutes and aortic clamp duration was 61 +/- 22 minutes. Cardiac outpu
t and pulmonary artery occlusion pressure were unchanged. The internal
mammary artery was anastomosed to the left anterior descending artery
(25) or the first diagonal (2) with patency shown in 25 of 27. One do
g in the survival study had a very short internal mammary artery pedic
le under tension and was euthanized for excessive postoperative hemorr
hage. Three weeks postoperatively the remaining dogs had angiographica
lly patent anastomoses, normal transthoracic echocardiograms, and hist
ologically normal healing and patent grafts. Conclusions. Endovascular
cardiopulmonary bypass using a balloon catheter is effective in arres
ting and protecting the heart to allow thoracoscopic internal mammary
artery-to-coronary artery anastomosis.