Regional Myocardial Blood Flow after Hypothermic Arrest and Cardioplegia

Abstract

Malperfusion due to increased coronary vascular resistance is presumably one of the factors responsible for incomplete functional recovery of the heart after aortic cross-clamping. Myocaridal blood flow (MBF, radioactive microspheres) was measured before and after 60 min of hypothermic ischemia in 16 dogs on cardiopulmonary bypass. After ischemia the hearts were reperfused for 30 min. MBF was measured in the empty beating heart and in the isovolumetrically contracting ventricle loaded with enddiastolic volumes (EDV) of 10, 20 and 30 ml (intraventricular latex balloon).

Myocardial Function, Blood Flow, and Metabolism with Different Forms of Myocardial Protection

“…The marked redu ct ion of LV func tion in all groups in spite of multi dose hypothermic cardioplegia is to some ex tent in co ntrast with the result s of other investigat ors (IS , 24,29,32). Thi s can be related in part to sh orter ischemic periods and shorter cardi oplegic reperfu sion interval s (15, 29 , 32) .…”

“…It is generally accepted that the application of pharmacological cardioplegia is a beneficial procedure in open heart surgery (28 , 30). Thu s. in nume rous experiment al (15 , 20), 24,27,32,36,42) and clinical (I , 3, 6, 12, 23, 35 ,3 9) studies cardioplegia has been shown to improve tolerance to myocardial ischemia.…”

Effect of Different Operative Techniques for Myocardial Revascularisation on Hemodynamics and Myocardial Perfusion in a Porcine Model

“…The major finding in our study were the results of regional myocardial perfusion. ECC with cardioplegia in contrast to earlier studies revealed uniform reperfusion after 40 minutes cardioplegic arrest without signs of microvascular obstruction [22]. As described by other groups transient microvascular obstruction as well as malperfusion after cold crystalloid cardioplegic arrest were not found [22,23].…”