Repeated epicardial coronary artery endothelial injuries lead to a global spontaneous coronary artery spasm.
OBJECTIVE
This study was conducted to develop a spontaneous coronary spasm model.


METHODS
Balloon endothelial denudation was carried out in the epicardial left anterior descending coronary artery (LAD) every 2 weeks, for a total of four times, in 12 pigs. Changes in the denuded site diameter and LAD blood flow caused by acetylcholine or serotonin were assessed before each denudation and at week 8. Blood pressure, electrocardiogram (ECG) from the LAD area and LAD blood flow were monitored continuously in conscious and unrestrained pigs.


RESULTS
Spontaneous ECG ST depression with a decrease in LAD blood flow appeared at around 2 weeks. In accordance with this, 0.5 microg/kg acetylcholine induced similar ECG and LAD blood flow changes without denuded site narrowing, suggesting microvascular spasm. Thereafter, ECG ST depression or elevation by serotonin via a denuded site spasm was found after 6 weeks and spontaneous ECG ST changes due to epicardial coronary artery spasm were observed.


CONCLUSIONS
Epicardial coronary artery endothelial injury may induce spontaneous vasospasticity in the downstream coronary microvessels as well as in the denuded portion, suggesting functional abnormality through the entire coronary arterial tree.
Saitoh
Shu-Ichi
S
First Department of Internal Medicine, Fukushima Medical University, Japan.
Muto
Misturu
M
Osugi
Taku
T
Aikawa
Kazuhiko
K
Matsumoto
Ken
K
Onogi
Futoshi
F
Maehara
Kazuhira
K
Ishibashi
Toshiyuki
T
Maruyama
Yukio
Y
D000109:Acetylcholine; D000704:Analysis of Variance; D000818:Animals; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000502:physiology; D003329:Coronary Vasospasm / Q000209:etiology*; D003331:Coronary Vessels / Q000293:injuries* / Q000503:physiopathology; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000293:injuries / Q000503:physiopathology; D008833:Microcirculation / Q000503:physiopathology; D010496:Pericardium; D012701:Serotonin; D013552:Swine
D012701:Serotonin; D000109:Acetylcholine