Optimal use of tolazoline in arteriography.

Intraarterial tolazoline, injected before the contrast medium in peripheral and visceral arteriography, has been shown to enhance the diagnostic value of the examination by inducing vasodilation. The time of maximal dilatation after injection, however, has not been clearly established. Photophlethysmography (PPG) was used to measure blood flow changes in 20 consecutive patients with lower-extremity arterial disease at rest and during the first 10 min after intraarterial tolazoline injection. Neither time to maximal dilatation (mean, 5.9 +/- 2.1 min) or PPG amplitude increase (mean, 251 +/- 177.2%) was significantly affected by the level of disease, severity of disease, or number of vessels present at the ankle. To make optimal use of tolazoline's vasodilatory effect, a waiting period of 6 min is recommended between tolazoline administration and contrast-medium injection in peripheral arteriography.