Clin Res Cardiol 101, Suppl 1, April 2012

V142 - Assessment of Myocardial Ischemic Burden by Three-Dimensional Whole-Heart Magnetic Resonance Perfusion Imaging
 
R. Manka1, I. Paetsch2, S. Kozerke3, C. Jahnke2
 
1Departement Innere Medizin, Klinik für Kardiologie, Universitätsspital Zürich, Zürich, Schweiz; 2Medizinische Klinik I - Kardiologie, Pneumologie und Angiologie, Universitätsklinikum Aachen, Aachen; 3Institut für Biomedizinische Technik, Zürich, Schweiz;
 
Background: Cardiac magnetic resonance (CMR) imaging enables noninvasive assessment of myocardial perfusion. Conventional 2D multi-slice CMR perfusion techniques yield high diagnostic accuracy but lack the information of the absolute amount of ischemia. Up to now, nuclear imaging methods have been the only methods to determine the amount of myocardial ischemia. Recently, 3D CMR perfusion has proven highly diagnostic for the detection of coronary artery disease (CAD) defined by quantitative coronary angiography (QCA). The present study aimed at relating significant coronary lesions as defined by fractional flow reserve (FFR) to the volume of myocardial ischemic burden (MIB) and to assess the inter-study reproducibility of 3D CMR perfusion imaging.
Methods: Sixty patients (mean age 64 ± 11 years, 12 female) with known or suspected CAD scheduled for invasive coronary angiography underwent a 1.5 Tesla (Philips Healthcare) CMR examination (TR/TE/flip angle: 1.8ms/0.7ms/15°,saturation prepulse delay: 150 ms, partial Fourier acquisition, 16 slices, voxel size: 2.3x2.3x5.0 mm³). Perfusion scans were obtained under adenosine stress (140 μg/kg/min for 6 min; 0.1mmol/kg Gd-DTPA) and at rest. FFR was recorded in all epicardial coronary arteries with luminal stenosis (≥ 50%). FFR <0.75 was considered significant. For determination of inter-study reproducibility ten patients underwent an repeat CMR examination. For visual analysis, 3D CMR perfusion scans were classified as pathologic if ≥1 segment showed an inducible perfusion deficit. MIB was measured by segmentation of the area of inducible ischemia and normalized to left-ventricular myocardial volume (MIB,%).
Results: All CMR and FFR studies were completed successfully. CAD prevalence as defined by FFR (<0.75) was 55% (33 of 60 patients). 3D CMR perfusion resulted in a sensitivity and specificity of 88% and 82%, respectively. Mean MIB in percentage of left ventricular myocardium was 19.9 ± 17.5% in patients with significant coronary artery stenosis (FFR <0.75) and 1.5± 3.8% in patients without significant CAD (FFR >0.75). Inter-study reproducibility of MIB measurements showed a high correlation (Pearson’s correlation coefficient, 0.97, p <0.0001). The Bland-Altman analysis revealed a mean bias for inter-study measurements of 0.6 ml (95% CI: -5.9 to 7.0).
Conclusions: Whole-Heart CMR perfusion provides high diagnostic accuracy for the detection of functionally significant CAD as defined by FFR. MIB measurements were highly reproducible and allowed the assessment of CAD severity.
 
Clin Res Cardiol 101, Suppl 1, April 2012
Zitierung mit Vortrags- oder Posternummer s.o.
DOI 10.1007/s00392-012-1100-6

http://www.abstractserver.de/dgk2012/ft/abstracts/V142.htm