The effect of intracoronary nicorandil on coronary myocardial bridging.
Medical treatments of coronary myocardial bridging (CMB) generally include beta-blockers and calcium channel blockers. Nitrates are avoided because symptoms may worsen. Nicorandil is a hybrid of a nitrate and a potassium channel opener. However, the effect of nicorandil on CMB is unknown. We analyzed nicorandil reactivity at the site with CMB in 51 patients. Maximal and minimal diameters of CMB were measured by quantitative angiography at baseline and at 60 seconds after intracoronary administration of 200 mg nicorandil. The maximal diameter during diastole increased from 2.15 + 0.42 mm to 2.34 + 0.44 mm after administration of nicorandil (P < .001), and the minimal diameter during systole increased from 1.24 + 0.63 mm to 1.67 + 0.64 mm (P < .001). Thus, nicorandil reduced the percentage vessel narrowing from 44.0 + 26.1% to 30.3 + 21.2% (P < .001). In 22 patients, we also evaluated the effect of nitroglycerin. The maximal diameter during diastole increased from 2.25 + 0.47 mm to 2.51 + 0.44 mm after administration of nitroglycerin (P < .019), and the minimal diameter during systole decreased from 1.28 + 0.64 mm to 1.14 + 0.60 mm (P = .276). Thus, nitroglycerin augmented the percentage vessel narrowing from 44.9% + 25.0% to 56.0% + 23.5% (P = .023). These results indicate that intracoronary administration of nicorandil could dilate coronary arteries during diastole as well as systole in patients with CMB during coronary angiography.
Jung
Jae-Hun
JH
Department of Internal Medicine, Hallym University Medical Center, Seoul, Republic of Korea.
Min
Pil-Ki
PK
Sung
Chong Won
CW
Lee
Sang-Hak
SH
Choi
Seonghoon
S
Cho
Jung Rae
JR
Lee
Namho
N
Park
Kyoung-Ha
KH
Kim
Min-Kyu
MK
Park
Woo Jung
WJ
Jang
Yangsoo
Y
D017023:Coronary Angiography; D003331:Coronary Vessels / Q000187:drug effects* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D054084:Myocardial Bridging / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D020108:Nicorandil / Q000008:administration & dosage*; D011446:Prospective Studies; D016896:Treatment Outcome; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000008:administration & dosage*
D014665:Vasodilator Agents; D020108:Nicorandil