Comparison of the Vasodilating Effect of Nitroglycerin, Verapamil, and Tolazoline in Hand Angiography

Abstract

To compare the vasodilating effect and safety of intraarterial verapamil with the long-accepted standard vasodilators nitroglycerin and tolazoline in hand angiography. The authors studied 25 patients who underwent brachial artery angiography. In 22 cases, there was poor or moderate visualization of the forearm and hand vasculature. To improve blood flow to the periphery, subsequent angiograms with intraarterial vasodilating agents were obtained. First, nitroglycerin was administered (n = 22). In cases of continuous poor or moderate visualization of the forearm and hand vasculature, another angiogram was obtained with verapamil (n = 21). If opacification remained poor or moderate, eventually tolazoline was injected (n = 20). To avoid pharmacologic interactions of the different vasodilating drugs, a minimum 15-minute interval between series was observed. The degree of opacification of the forearm and hand arteries was graded on a scale from 1 to 5: visualization of the forearm arteries only was defined as 1, of the forearm arteries and superficial/deep palmar arch as 2, of the forearm arteries, superficial/deep palmar arch, and digital arteries to the level of the metacarpophalangeal joints as 3, to the level of the proximal interphalangeal joints as 4, and to the distal interphalangeal joints as 5. All three vasodilating agents demonstrated highly significant improvement in blood flow; verapamil and tolazoline showed statistically greater effects than nitroglycerin. Verapamil caused the fewest and least severe adverse effects. Intraarterial verapamil and tolazoline are comparable in terms of vasodilatory efficacy in hand arteries. However, because of its favorable adverse effect profile, verapamil is recommended for optimizing visualization of the peripheral arterial vascular system.