Hemodynamic observations in patients with left ventricle to aorta conduit.

Fourteen patients who had a left ventricular apex to abdominal aorta composite conduit implanted for relief of severe left ventricular outflow tract obstruction were studied at cardiac catheterization 7 days to 19 months postoperatively (median 12 days). Analysis of pressure, angiographic and blood flow velocity data showed the following: (1) The left ventricle to aorta pressure gradients were reduced from an average preoperative value of 100.6 mmHg (range 54 to 140) to an average of 22.1 mm Hg (range 0 to 60) postoperatively; (2) postoperative left ventricular end-diastolic volume averaged 87.5 percent of normal (range 51 to 146); (3) cardiac index and ejection fraction were normal postoperatively in all but one patient. Left ventricular and aortic angiography revealed blood flow through both the ascending aorta and conduit in all patients and retrograde flow of blood from the conduit to the aortic arch in four. An average of 36 percent (range 16 to 50) of the left ventricular output was ejected through the conduit. It appears that this operation is effective in relieving severe and otherwise inoperable left ventricular outflow tract obstruction and in preserving or improving left ventricular function and aortic hemodynamics.