The Journal of Thoracic and Cardiovascular Surgery, Vol 100, 569-579, Copyright © 1990 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Functional consequences of the right ventricular isolation procedure
RJ Damiano Jr, T Asano, PK Smith, TB Ferguson and JL Cox
Department of Surgery, Duke University Medical Center, Durham, N.C.
The right ventricular free wall was surgically isolated from the remainder
of the heart in eight dogs to evaluate the functional consequences of this
procedure. Each dog was instrumented with ultrasonic dimension transducers
in the right and left ventricular free walls, intracavitary
micromanometers, and pulmonary artery flow probes. Volume loading and vena
caval occlusions were performed to assess diastolic compliance and systolic
function. Right ventricular unstressed myocardial segment length increased
from 14.2 +/- 0.7 to 15.0 +/- 0.8 mm (p less than 0.5). There was an
accompanying significant postoperative loss of right ventricular diastolic
compliance (p less than 0.005). Regional right ventricular systolic
function and regional left ventricular diastolic compliance and systolic
function were preserved after the procedure. Postoperatively, when the
right ventricular free wall was not paced and left silent, right
ventricular stroke work decreased from 7.0 +/- 0.8 to 2.7 +/- 0.5 gm-m/m2
(p less than 0.05). These data demonstrate that the diastolic compliance of
the right ventricular free wall decreases significantly after right
ventricular isolation. However, there were no changes in regional right
ventricular systolic or regional left ventricular function. The isolated
right ventricular free wall contributes significantly to postoperative
cardiac performance.
