Plaque components at coronary sites with focal spasm in patients with variant angina: virtual histology-intravascular ultrasound analysis.
BACKGROUND
We compared the plaque components at coronary sites with focal spasm after ergonovine provocation test in 30 variant angina (VA) patients with those at culprit coronary sites in 32 unstable angina (UA) patients using virtual histology-intravascular ultrasound (VH-IVUS).


METHODS
VH-IVUS classified and color-coded tissue into four major components: fibrotic; fibro-fatty; dense calcium (DC); and necrotic core (NC). Thin-cap fibroatheroma (TCFA) was defined as a NC≥10% of plaque area in at least 3 consecutive frames without overlying fibrous tissue in the presence of ≥40% plaque burden.


RESULTS
The lesion site plaque burden was significantly smaller (44.5±10.8% vs. 70.5±13.1%, p<0.001), the plaque volume was significantly smaller (135±118 mm³ vs. 223±160 mm³, p=0.020), the remodeling index was significantly lower (0.90±0.14 vs. 0.97±0.23, p=0.023), and more plaque was hypoechoic with less calcium (87% vs. 56% and 0% vs. 19%, respectively, p=0.033) in VA patients compared with UA patients. The % NC and DC areas were significantly smaller at the minimum lumen site within spasm/culprit lesion (12.9±12.9% vs. 22.3±11.7%, p=0.004, and 6.5±8.0% vs. 12.8±10.8%, p=0.011, respectively), and the % NC and DC volumes were significantly smaller in VA patients compared with UA patients (12.2±10.3% vs. 17.7±8.1%, p=0.025, and 6.4±6.0% vs. 11.8±8.5%, p=0.007, respectively). The TCFA within lesion segments was less frequently observed in VA patients compared with UA patients (13% vs. 53%, p=0.001).


CONCLUSIONS
VA patients have less plaque, more negative remodeling behavior, more hypoechoic plaque with less calcification, and less NC- and DC-containing lesions and less TCFA lesions compared with UA patients.
Hong
Young Joon
YJ
Heart Center of Chonnam National University Hospital, Chonnam National University Research Institute of Medical Sciences, Gwangju, Republic of Korea.
Jeong
Myung Ho
MH
Choi
Yun Ha
YH
Ma
Eun Hye
EH
Ko
Jum Suk
JS
Lee
Min Goo
MG
Park
Keun Ho
KH
Sim
Doo Sun
DS
Yoon
Nam Sik
NS
Youn
Hyun Ju
HJ
Kim
Kye Hun
KH
Park
Hyung Wook
HW
Kim
Ju Han
JH
Ahn
Youngkeun
Y
Cho
Jeong Gwan
JG
Park
Jong Chun
JC
Kang
Jung Chaee
JC
D000328:Adult; D000368:Aged; D000788:Angina Pectoris, Variant / Q000000981:diagnostic imaging* / Q000473:pathology*; D000789:Angina, Unstable / Q000000981:diagnostic imaging / Q000473:pathology; D003329:Coronary Vasospasm / Q000139:chemically induced; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000187:drug effects / Q000473:pathology*; D003937:Diagnosis, Differential; D018450:Disease Progression; D004874:Ergonovine; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging / Q000473:pathology*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional; D014662:Vasoconstrictor Agents
D014662:Vasoconstrictor Agents; D004874:Ergonovine