The Journal of Thoracic and Cardiovascular Surgery, Vol 104, 248-255, Copyright © 1992 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Hemodynamic evaluation of heterotopic heart transplantation
M Rigaud, JP Bourdarias, E el Khoury, A Beauchet, F Labedan, J Bardet, I Gandjbakhch and C Cabrol
Department of Cardiology, Hopital Ambroise Pare, Boulogne, France.
To assess the relative contribution of native and donor hearts to total
circulatory performance after heterotopic transplantation, we used cardiac
catheterization to examine 10 patients. Left and right ventricular filling
pressures significantly decreased by 41% and 36%, respectively, cardiac
index increased by 25%, and pulmonary arteriolar resistance was reduced by
61%. Patients were subdivided into two groups according to the presence of
one (group I) or two (group II) peaks on the aortic pressure curve. In
group I, the donor left ventricle assumed total left ventricular work and
80% of right ventricular work. Because the native left ventricle could not
generate enough pressure to open the aortic valve, its entire stroke volume
was ejected into the common left atrium. In addition, in all four patients
a native aortic regurgitation occurred in diastole and systole. In
contrast, in group II, native left ventricular systolic pressure always
exceeded aortic diastolic pressure. The donor left ventricle contributed
68% to systemic blood flow and the donor right ventricle 51% to pulmonary
blood flow. Mild native aortic regurgitation was demonstrated in two
patients only. Native left ventricular function deteriorated
postoperatively in all patients (ejection fraction decreased from 0.22 +/-
0.09 to 0.14 +/- 0.08), but this deterioration was more marked in group I.
Postoperative depression of native left ventricular function could not be
ascribed to progression of coronary artery disease but was mainly due to
reduced preload (competitive filling) and increased afterload. Thus in
group I patients with more severe preoperative left ventricular
dysfunction, the donor heart behaved like a total biventricular assist
device. In contrast, in group II patients the donor heart acted like a
partial biventricular assist device.