A comparative study of eccentric and concentric coronary stenosis vasomotion in patients with Prinzmental's variant angina and patients with stable angina pectoris

The eccentric lumenology

Coronary angiography has a poor predictive value for the detection of eccentric plaque morphology. Many reports have demonstrated discordance between the angiographic classification and the intravascular ultrasound (IVUS) classification. Although eccentricity is usually considered a dichotomous character, more than two-thirds of all coronary stenosis have some degree of eccentricity. The American College of Cardiology/American Heart Association (ACC/AHA) Task force included lesion eccentricity as a risk factor for moderate procedural success (60-85%) and moderate complications (type B). Although lesion eccentricity has been implicated as a risk factor for reduced short-term procedural results, current available data does not support the adverse impact of eccentricity on procedural success or restenosis. The present article reviews the incidence and the various clinical scenarios known to be associated with the eccentric lumenogram and the impact of coronary artery remodeling contributing to misinterpretation of disease eccentricity. Various therapeutic modalities with reference to eccentric lesions are also considered.

Plaque Morphology at Coronary Sites With Focal Spasm in Variant Angina-Study Using Intravascular Ultrasound-

In the present study, the intravascular ultrasound (IVUS) morphologic appearance of coronary atherosclerotic plaque associated with focal spasm was prospectively studied in 45 patients with or without focal coronary spasm provoked by ergonovine or acetylcholine. The percent plaque area and plaque arc were determined from the IVUS images at the sites of spasm. Calcified lesion was defined as the presence of high-intensity echo with acoustic shadowing. Twenty-three patients had focal coronary spasm defined as angiographic narrowing >75% and IVUS demonstrated atherosclerotic plaque in these 23 sites. In the 22 patients without focal spasm, IVUS demonstrated 18 atherosclerotic lesions in 17 patients and the remaining 5 patients did not have significant lesions. There was no difference in the percent plaque area and plaque arc between plaque lesions with (47+/-10%, 298+/-71 degrees ) and without (39+/-15%, 249+/-83 degrees ) coronary spasm. Interestingly, calcified lesion was less frequently present at the sites with than at those without spasm (p<0.05). These results indicate that the presence of plaque without calcification is likely to be related to the occurrence of focal vasospasm, although the severity and distribution of the disease did not differ between each patient group.