Relationship between cardiovascular risk as predicted
by established risk scores and coronary artery plaque
composition as detected by virtual histology intravascular
ultrasound analysis: the PREDICT pilot study
Mohamed Abdel-Wahab
1,2
*, MD; Ahmed A. Khattab
1,2
, MD; Branislav Liska
1
, MD; Ralph Toelg
1
, MD;
Walid El-Hammady
2
, MD; Nabil Farag
2
, MD; Volker Geist
1
, MD; Ali Ramzy
2
, MD; Gert Richardt
1
, MD
1. Herz-Kreislauf-Zentrum, Segeberger Kliniken GmbH (Academic Teaching Hospital of the University of Kiel), Bad Segeberg,
Germany; 2. Cardiology Department, Ain Shams University Hospitals, Cairo, Egypt
This study was supported by an educational grant from Novartis, Germany
Abstract
Aims: Identification of subclinical high-risk plaques is potentially important because they may have greater
likelihood for rupture and thrombosis. The aim of this study was to assess the relationship between in vivo
coronary artery plaque composition using intravascular ultrasound virtual histology (IVUS-VH) and
cardiovascular risk as predicted by clinical risk scores in patients with non-obstructive stable coronary
artery disease.
Methods and results: Forty patients undergoing elective coronary angiography revealing <50% coronary
artery stenoses were prospectively included. Of these, 38 (29 men; mean age 65±9 years) underwent a
satisfactory IVUS-VH investigation of the affected vessel. For each patient, the 10-year risk of cardiovascular
events was calculated using the Framingham and the SCORE-Deutschland risk prediction algorithms, and
compared to the VH-derived plaque composition at the site of the minimal lumen area (MLA).
For both algorithms, patients at low estimated risk of events showed more fibrous tissue percentages than
patients at high risk (67.4±9.7% versus 53.2±10.4% for the SCORE algorithm, and 65.6±13.4% versus
51.5±9.4% for the Framingham algorithm, p=0.002 and p=0.004, respectively). Plaques of patients with
higher risk showed a non-significantly higher necrotic core percentage. For the SCORE algorithm, dense
calcium percentage was higher in patients with high risk compared to patients with low risk (13.9±10.4%
versus 4.9±4.9%, p=0.008). The prevalence of IVUS-derived thin cap fibro-atheromas at the MLA site was
higher in patients at high risk (80% of lesions in patients at high risk using the SCORE algorithm and 92%
of lesions in patients at high risk using the Framingham algorithm), whereas patients at low risk had more
stable plaque phenotypes (p=0.002 and 0.003 for the SCORE and Framingham algorithms, respectively).
Conclusions: In vivo plaque composition and morphology assessed by IVUS-VH were related to the
cardiovascular risk predicted by established risk prediction algorithms in patients with non-obstructive
coronary artery disease, suggesting a link between the higher risk for future events and the VH-derived
plaque morphology.
KEYWORDS
Virtual histology,
imaging,
atherosclerosis,
coronary disease, risk
* Corresponding author: Herz-Kreislauf-Zentrum, Segeberger Kliniken GmbH, Am Kurpark 1, 23795 Bad Segeberg, Germany
E-mail: msabdelwahab@gmail.com
© Europa Edition 2007. All rights reserved.
- 482 -
Clinical research
EuroInterv.2007;3:482-489