Provocation of microvessel spasm by low-dose acetylcholine in patients with suspected coronary artery disease--two case reports.
Endothelial dysfunction plays an important role in the pathogenesis of cardiac syndrome X, and intracoronary low-dose acetylcholine infusion is a widely used diagnostic modality for studying the coronary artery endothelial function. The authors herein report 2 cases of cardiac syndrome X with coronary artery endothelial dysfunction and microvessel spasm. The findings of non-invasive testing were positive for ischemia. Coronary angiograms appeared entirely normal in both cases. However, the intracoronary infusion of low-dose (1.5-15 microg/minute) acetylcholine demonstrated an impairment of the coronary blood flow response and consequently provoked an ST-segment elevation in an electrocardiogram. The coronary angiograms showed no spasm in the epicardial arteries. These patients are thus suggested to have cardiac syndrome X with microvessel spasms associated with coronary artery endothelial dysfunction.
Masaki
Nobuyuki
N
The First Department of Internal Medicine, National Defense Medical College, Saitama, Japan.
Takase
Bonpei
B
Satomura
Kimio
K
Akima
Takashi
T
Matsushima
Yoshihiro
Y
Hosaka
Haruhiko
H
Hamabe
Akira
A
Kurita
Akira
A
Ohsuzu
Fumitaka
F
D000109:Acetylcholine; D001783:Blood Flow Velocity / Q000187:drug effects; D018678:Cholinergic Agents; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology; D003327:Coronary Disease / Q000175:diagnosis* / Q000503:physiopathology; D003329:Coronary Vasospasm / Q000139:chemically induced* / Q000503:physiopathology; D003937:Diagnosis, Differential; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology; D005260:Female; D006801:Humans; D007269:Injections, Intra-Arterial; D018810:Magnetic Resonance Angiography; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000503:physiopathology; D017566:Microvascular Angina / Q000175:diagnosis* / Q000503:physiopathology; D008875:Middle Aged
D018678:Cholinergic Agents; D000109:Acetylcholine