The Journal of Thoracic and Cardiovascular Surgery, Vol 98, 1077-1082, Copyright © 1989 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Right ventricular myocardial protection through intracavitary cooling in cardiac operations
AR Velardi, SJ Widmer, JH Cilley Jr, RK Spence, TA Witkowski and AJ DelRossi
Department of Surgery, Cooper Hospital/University Medical Center, Camden, NJ 08103.
In an attempt to protect the right ventricle, we designed and tested a
closed cooling system that circulates cold saline through a double- lumen,
balloon-tipped catheter positioned in the right ventricular cavity.
Fourteen sheep were randomly assigned to two groups. In group A (n = 7),
the right ventricular cooling catheter system was used in addition to
coronary cardioplegic perfusion and systemic hypothermia for myocardial
protection. Group B (n = 7) served as a control group. In group A, the
right ventricular temperatures were significantly lower than those of the
control group (16.1 degrees +/- 0.3 degrees C versus 23.9 degrees +/- 0.4
degrees C; p less than 0.0001, Student's t test). The most common
temperature range was 12 degrees to 18 degrees C (67.1%, frequency
distribution analysis), and 63.2% of temperatures were below 16 degrees C.
The catheter system also maintained the temperatures of the
interventricular septum at a lower level than those recorded in the control
group and prevented septal rewarming, which was significant in group B
(from 16.5 degrees +/- 1.5 degrees C to 25.0 degrees +/- 0.9 degrees C; p
less than 0.04, Mann-Whitney U test). Left ventricular temperatures were
not changed by the catheter system. By better cooling the right ventricle
and the septum, the right ventricular cooling catheter system should
decrease the prevalence of right ventricular failure and allow more time to
safely complete multiple coronary anastomoses in coronary artery bypass
graft operations.
