Target lesion thin-cap fibroatheroma defined by virtual histology intravascular ultrasound affects microvascular injury during percutaneous coronary intervention in patients with angina pectoris.
BACKGROUND
Several reports suggest that virtual histology intravascular ultrasound (VH-IVUS) assessment could predict microvascular damage during percutaneous coronary intervention (PCI). A novel index of microcirculatory resistance (IMR) has been developed as a reproducible and less hemodynamic-dependent index. The purpose of this study was to investigate the relationship between thin-cap fibroatheroma (TCFA) defined by VH-IVUS and a change in the IMR during PCI in patients with angina pectoris (AP).


RESULTS
The study investigated 30 lesions from 28 AP patients. VH-IVUS imaging was performed before PCI. TCFA was defined as the presence of confluent necrotic core (>10%) without detectable overlying fibrous cap segment. Patients were divided into 2 groups according to the presence of TCFA. Using a pressure guidewire, IMR were measured before and after PCI. After successful PCI, patients were prospectively followed up clinically. TCFA was detected in 9 lesions (30%). IMR tended to improve after PCI in the non-TCFA group, but tended to worsen in the TCFA group. DeltaIMR (=IMR after PCI-IMR before PCI) was significantly higher in the TCFA group compared with the non-TCFA group (13.2+/-29.9 vs -4.4+/-16.0, P=0.04). During follow-up (mean 20 months), survival free of major adverse cardiac events was significantly less in the TCFA group than in the non-TCFA group.


CONCLUSIONS
Target lesion TCFA may be related to both microvascular injury and the long-term clinical outcome after successful PCI in patients with AP.
Yamada
Ryotaro
R
Division of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
Okura
Hiroyuki
H
Kume
Teruyoshi
T
Neishi
Yoji
Y
Kawamoto
Takahiro
T
Miyamoto
Yoshinori
Y
Imai
Koichiro
K
Saito
Ken
K
Tsuchiya
Tetsuo
T
Hayashida
Akihiro
A
Yoshida
Kiyoshi
K
D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000628:therapy*; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D055806:Microvessels / Q000293:injuries*; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000150:complications* / Q000175:diagnosis / Q000000981:diagnostic imaging*; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional; D014655:Vascular Resistance