Heparin-coated shunts for lesions of the descending thoracic aorta. Experimental and clinical observations
W. G. Wolfe, L. H. Kleinman, A. S. Wechsler and D. C. Sabiston Jr
Heparin sodium-coated shunts are employed frequently to maintain trunk and
lower extremity perfusion during temporary occlusion of the descending
thoracic aorta. In the past five years, this shunt has been used in a
series of 39 patients ranging in age from 19 to 72 years old, with 34
survivors (87%). The proximal end of the shunt was placed in the subclavian
artery in 17 patients, the left ventricle in ten, and in the ascending or
transverse aortic arch in 12. The distal end of the shunt was placed either
in the lower thoracic aorta or in the femoral artery. For further
evaluation of effectiveness, paired observations were made in dogs to
determine the physiological consequences with the proximal end of the shunt
inserted at two different sites. Although neither shunt decompressed the
left ventricle fully, the subclavian-femoral shunt was significantly more
effective than was the left ventricle-femoral artery bypass. If a choice
exists for sites of insertion of the shunt, it appears that it should be
placed distal to the aortic valve, since this position provides the least
increase in systolic blood pressure and is associated with a lower demand
for myocardial blood flow.
