Rn. Gates et al., THE MICROVASCULAR DISTRIBUTION OF CARDIOPLEGIC SOLUTION IN THE PIGLETHEART - RETROGRADE VERSUS ANTEGRADE DELIVERY, Journal of thoracic and cardiovascular surgery, 105(5), 1993, pp. 845-853
The uniform distribution of cardioplegic solution to all areas of the
microvasculature is considered critical for myocardial protection. Des
pite this, little information exists regarding the ability of retrogra
dely infused cardioplegic solution to perfuse the microvasculature of
the heart. In this report, the microvascular distribution of retrograd
ely delivered cardioplegic solution was studied by means of a techniqu
e to quantitatively demonstrate capillary perfusion. Duroc piglet hear
ts were subjected to either antegrade (n = 4) or retrograde (n = 8) pe
rfusion fixation with 2.5% glutaraldehyde and subsequently perfused wi
th NTB-2 (an intracapillary marker). The results indicate that retrogr
adely delivered NTB-2 consistently perfused the anterior half of the i
ntraventricular septum and the anterior and lateral free walls of the
left ventricle but inconsistently perfused the posterior half of the i
ntraventricular septum, the posterior wall of the left ventricle, and
a small paraseptal region of the right ventricle. The remainder of the
right ventricle was not perfused. In contradistinction, all regions o
f the heart were consistently perfused by the antegrade technique. In
regions of the heart in which retrograde microvascular perfusion occur
red, no statistical difference was found in the quantitative degree of
capillary perfusion achieved by either the antegrade or retrograde te
chnique. These results have important implications for planning strate
gies of myocardial protection and suggest that further investigation c
oncerning the microvascular distribution of retrogradely delivered car
dioplegic solution in human beings is merited.