Effects of Various Doses of Intracoronary Verapamil on Coronary Resistance Vessels in Humans

• Published in: JAPANESE CIRCULATION JOURNAL Vol. 61; no. 9; pp. 755 - 761
• Main Authors: Ishihara, Masaharu, Sato, Hikaru, Tateishi, Hironobu, Kawagoe, Takuji, Shimatani, Yuji, Kurisu, Satoshi, Sakai, Kazuko, Ueda, Kentarou
• Format: Journal Article
• Language: English
• Published: Kyoto The Japanese Circulation Society 1997; Japanese Circulation Society
• Subjects: Adult; Aged; Atrioventricular Node - drug effects; Biological and medical sciences; Calcium channel blocker; Cardiovascular system; Coronary Angiography; Coronary circulation; Coronary Doppler guide wire; Coronary Vessels - drug effects; Dose-Response Relationship, Drug; Electrocardiography - drug effects; Female; Hemodynamics - drug effects; Humans; Male; Medical sciences; Middle Aged; Papaverine - pharmacology; Pharmacology. Drug treatments; Vascular Resistance; Vasodilator Agents - pharmacology; Vasodilator agents. Cerebral vasodilators; Verapamil - pharmacology; Human; Pharmacologic test; Vasodilator agent; Vascular resistance; Calcium antagonist; Coronary artery; Aralkylamine; Verapamil; Intraarterial administration; Hemodynamics; Dose activity relation
• ISSN: 0047-1828; 1347-4839
• DOI: 10.1253/jcj.61.755

To investigate the vasodilatory effect of various doses of intracoronary verapamil on coronary resistance vessels, we studied 13 patients with normal angiograms. A coronary Doppler guide wire was inserted into the left anterior descending coronary artery, and coronary blood flow velocity (CBFV) was measured. Verapamil was injected into the left coronary artery at doses of 0.1 mg, 0.5 mg, 1.0 mg, and 2.0 mg at 10-min intervals. Nitroglycerin was also injected into the same artery to avoid changes in cross-sectional area. As a measure of coronary vascular resistance, coronary vascular resistance index (CVRI) was calculated as the quotient of mean aortic pressure/CBFV. An injection of verapamil produced a dose-dependent increase in CBFV: 79±38% with 0.1 mg, 131±56% with 0.5 mg, 143±46% with 1.0 mg, and 128±47% with 2.0 mg of verap-amil. The percent peak decreases in CVRI were dose dependent: -42±13% with 0.1 mg, -50±17% with 0.5 mg, -62±14% with 1.0 mg, and -60±9% with 2.0 mg of verapamil. Thus, intracoronary verapamil produces a dose-dependent dilation of coronary resistance vessels, and the optimal effect is produced with an injection of verapamil at a dose of 1.0 mg into the left coronary artery. At this dose, verapamil did not affect atrioventricular conduction. (Jpn Circ J 1997; 61: 755 - 761)