Effect of retrograde warm continuous cardioplegia on right ventricular function.
BACKGROUND
Although retrograde warm continuous cardioplegia (RWCC) has been recently advocated as a method of myocardial preservation during cardiac surgery, scant data exist on the effects of RWCC on right ventricular function. However, previous data have clearly shown that retrograde cardioplegia is poorly distributed to the right ventricle and interventricular septum. This experiment was performed to analyze functional preservation of the right ventricle after RWCC.


RESULTS
Fourteen mongrel dogs were instrumented with sonomicrometers and pressure transducers to determine left and right ventricular (LV, RV) pressure-volume relationships and placed on cardiopulmonary bypass. All dogs underwent 90 minutes of aortic cross-clamping with either (1) RWCC (n = 7) after antegrade warm arrest or (2) retrograde cold multidose cardioplegia (RCMC) (n = 7) with topical hypothermia after antegrade cold arrest. All dogs received identical blood cardioplegia solutions. Ventricular function was measured before arrest and 30 and 60 minutes after unclamping. The end-diastolic-work area relationship was calculated, and the slope is presented as percent of baseline (mean +/- SEM; repeated measures ANOVA). At 30 minutes after unclamping, RWCC provided 68.77 +/- 9.09 for the left ventricle and 41.03 +/- 7.49 (P < .05 for RWCC versus RCMC for RV function at 30 minutes) for the right ventricle, and RCMC provided 62.80 +/- 7.23 for the left ventricle and 79.40 +/- 13.82 for the right ventricle. At 60 minutes after unclamping, RWCC provided 58.24 +/- 12.35 for the left ventricle and 48.05 +/- 9.72 for the right ventricle, and RCMC provided 65.38 +/- 6.76 for the left ventricle and 61.95 +/- 8.70 for the right ventricle. (P = NS for RWCC versus RCMC for LV function at either 30 or 60 minutes). These results demonstrate depressed recovery of RV function after 90 minutes of RWCC (P < .05 at 30 minutes after reperfusion) compared with RCMC. No difference in recovery of LV function was detected.


CONCLUSIONS
RWCC may be harmful to the right ventricle and should be used with caution, particularly in patients with preexisting RV hypertrophy.
LeBoutillier
M
M
Department of Surgery, New York University Medical Center, NY 10016.
Grossi
E A
EA
Steinberg
B M
BM
Baumann
F G
FG
Colvin
S B
SB
Spencer
F C
FC
Galloway
A C
AC
D000818:Animals; D001769:Blood; D002314:Cardioplegic Solutions; D002315:Cardiopulmonary Bypass; D004285:Dogs; D006324:Heart Arrest, Induced / Q000009:adverse effects / Q000379:methods*; D007036:Hypothermia, Induced; D009206:Myocardium / Q000648:ultrastructure; D013696:Temperature; D013997:Time Factors; D016277:Ventricular Function, Left; D016278:Ventricular Function, Right
D002314:Cardioplegic Solutions