Intravascular Ultrasonographic Detection of Atherosclerotic Lesions in Spastic Segments of the Coronary Arteries in Patients with Variant Angina

ABSTRACT

Coronary artery spasm plays an important role for evoking myocardial ischemia and infarction as well as sudden cardiac death in patients with variant angina. The coronary anatomy in patients with variant angina has been defined both at autopsy and during coronary arteriography. Severe porximal coronary atherosclerosis of at least one major vessel occurs in 3/4 of patients and the remainder have normal coronary arteries. Coronary angiography is a relatively insensitive diagnostic tool especially in the early stages of coronary artery disease. Due to arterial remodelling, angiographic luminogram may show little or no narrowing even though a large part of the total vessel area is occupied by plaque. Intravascular ultrasonography(IVUS) enables accurate determination of vessel dimensions and wall characteristics and is more sensitive in delineating early intimal changes than angiography. We experienced 2 cases that IVUS showed focal or diffuse atherosclerosis in spastic segments of the coronary arteries, even though they appeared angiographically normal.