A. Ardehali et al., VENTRICULAR EFFLUENT OF RETROGRADE CARDIOPLEGIA IN HUMAN HEARTS HAS TRAVERSED CAPILLARY BEDS, The Annals of thoracic surgery, 60(1), 1995, pp. 78-83
Background. In human hearts, as much as two thirds of retrograde cardi
oplegia is shunted through thebesian and arteriosinusoidal channels in
to the ventricular cavities. This ventricular effluent is believed to
have bypassed the myocardial capillary beds and is therefore considere
d nonnutritive. Methods. To test this hypothesis, we studied the expla
nted hearts from 9 cardiac transplant recipients with the diagnosis of
idiopathic cardiomyopathy. These hearts were arrested in situ with co
ld blood cardioplegia and excised with the coronary sinus intact. The
left and right coronary ostia and the coronary sinus then were cannula
ted. Colored microspheres (15 +/- 5 mu m) mixed in 37 degrees C blood
cardioplegia were administered through the coronary sinus at a pressur
e of 30 to 40 mm Hg. Effluents from the coronary arteries and ventricu
lar chambers were collected and analyzed for microsphere concentration
. Results. Approximately 80% of retrograde cardioplegia solution was r
ecovered in the ventricular chambers. Nearly 40% of this ventricular c
hambers effluent had traversed capillary beds and, thus, we believe ha
s nutritive properties. Almost all of the coronary artery effluent of
retrograde cardioplegia solution had traversed capillary beds. The tot
al nutritive fraction of retrograde warm blood cardioplegia in this ex
planted human heart model was approximately 55%. Conclusions. These fi
ndings suggest that the ventricular chamber effluent of retrograde blo
od cardioplegia contributes to the metabolic homeostasis of the arrest
ed human heart.