Does diltiazem provide higher internal mammary artery flow than nitroglycerin during coronary artery bypass grafting surgery?
Diltiazem infusion which started prior to harvesting provided higher IMA blood flow compared to nitroglycerin infusion. Considering the percentage of increases in flows after resection of distal segment, the most prone part to vasospasm, we assume that a certain amount of spasm occurred in IMA in spite of infusion of study drugs, such that less with diltiazem and more with nitroglycerin. Diltiazem plays more important role than nitroglycerin in the prevention of vasospasm.
Therapeutic levels of neither dobutamine nor levosimendan showed inotropic oxygen wasting in this in vivo pig model. Thus, relevant hemodynamic responses can be achieved with an adrenergic inotrope without surplus oxygen consumption.