Dose- and time-related vasodilator response of conduit coronary arteries to intracoronary isosorbide dinitrate in human beings.
The time course of the vasodilation of different segments of the epicardial coronary vasculature after three different doses of intracoronary isosorbide dinitrate (ISDN) was investigated in angiographically normal coronary arteries in 10 patients with quantitative coronary angiography. In five patients, 0.1 mg and 0.3 mg ISDN were injected intracoronary 30 minutes apart, and the effect of each dose was assessed at 1, 5, 10, and 15 minutes after the administration by serial angiograms. In five additional patients, a single dose of 3 mg was injected and coronary vasodilation was assessed at 1, 5, 10, 15, and 20 minutes. After each dose, dilation of epicardial coronary arteries occurred within 1 minute, peaked at 5 minutes and progressively decreased thereafter. Relative to control, peak percent diameter increase was (mean +/- SEM) 10% +/- 0.9% (p less than 0.01), 18.5% +/- 1.5% (p less than 0.01), and 26% +/- 2.1% (p less than 0.01) after 0.1, 0.3, and 3.0 mg, respectively. When small (1 to 2 mm), medium (2 to 3 mm), and large (greater than 3 mm) vessels were separately analyzed, peak response was respectively 12% +/- 1.3% (p less than 0.01), 9% +/- 1.9% (p less than 0.01), and 7% +/- 1% (p less than 0.05) after 0.1 mg ISDN; 22% +/- 1.8% (p less than 0.01), 16% +/- 1.3% (p less than 0.01), and 12% +/- 0.8% (p less than 0.01) after 0.3 mg; and 38% +/- 2.4% (p less than 0.01), 22% +/- 2.1% (p less than 0.01), and 17% +/- 2% (p less than 0.01) after 3.0 mg. The duration of the response increased with the dose, but was inversely related to the size of the vessel.(ABSTRACT TRUNCATED AT 250 WORDS)
Simonetti
I
I
CNR Institute of Clinical Physiology, Pisa, Italy.
Michelassi
C
C
De Caterina
R
R
Marzilli
M
M
L'Abbate
A
A
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D003331:Coronary Vessels / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007269:Injections, Intra-Arterial; D007548:Isosorbide Dinitrate / Q000494:pharmacology*; D008875:Middle Aged; D013997:Time Factors; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; D007548:Isosorbide Dinitrate