Author + information
- Tomokazu Iguchi,
- Yasuhiko Takemoto,
- Kenei Shimada,
- Kenji Matsumoto,
- Yasukatsu Izumi,
- Yasuhiro Nakamura,
- Akihisa Hanatani and
- Minoru Yoshiyama
The validity of semi-automated intima-media thickness (balMT) and flow-mediated dilatation (FMD) measurements from the brachial artery and clinical implication of balMT are unknown. We sought to validate the accuracy of a new semi-automated ultrasound system for the measurement of balMT and FMD and examine the relationships among balMT, FMD, clinical variables, and Framingham Risk Score (FRS) as a predictor of coronary heart disease (CHD).
Forty-seven patients (61±13 years) with atherosclerotic risk factors and 23 normal healthy volunteers (25 ± 4 years) were consecutively enrolled into a validation study (Study 1). BalMT and FMD were measured simultaneously using a semi-automatic vessel wall tracking software program and compared with those of manual measurements as a reference standard in Study 1. In addition, 218 patients with risk factors (60 ± 12 years) were consecutively enrolled for examining the relationships among balMT, FMD, clinical variables, and FRS (Study 2).
Measurements of FMD and balMT by the software program showed good correlations with those by the manual measurement (Study 1). On multivariate analysis, balMT correlated independently with age, brachial artery diameter and FMD. In 200 patients with risk factors and no CHD, FMD and balMT were significantly correlated with FRS (study 2). Optimal cutoff values of FMD (5.48%) and balMT (0.34mm) were determined based on the receiver-operating-characteristic curve analyses for predicting ten-year Framingham risk no less than 10%, and the subjects were classified into three groups: Group A (n=71): FMD ≥5.48% and IMT <0.34mm; Group B (n=76): FMD ≥5.48% and IMT ≥0.34mm or FMD <5.48% and IMT <0.34mm; Group C (n=53): FMD <5.48% and IMT ≥0.34mm. Ten-year Framingham risk was markedly higher in Group C (21.8 ± 11.4%) than Group A (10.9 ± 9.4%, p<0.0001) or Group B (13.9 ± 9.1%, p<0.0001).
The newly developed semi-automated software measurements provide reliable evaluations of balMT and FMD simultaneously. BalMT derived by this software may add prognostic information to FMD in patients with atherosclerotic risk factors and no CHD.
Poster Sessions, Expo North
Sunday, March 10, 2013, 9:45 a.m.-10:30 a.m.
Session Title: Imaging: Echo – Contrast Echocardiography/Vascular Imaging
Abstract Category: 18. Imaging: Echo
Presentation Number: 1225-329
- 2013 American College of Cardiology Foundation