AIM: Multidetector CT bests MRI in ruling out coronary artery disease
Image source: GE Healthcare |
Senior author Marc Dewey, MD, PhD, and colleagues from Charité Medical School in Berlin sought to compare CT and MRI for ruling out clinically significant CAD in adults with suspected or known CAD.
The researchers included prospective English- or German-language studies (from MEDLINE, EMBASE, and ISI Web of Science) that compared CT or MRI with conventional coronary angiography in all patients that included sufficient data for compilation of 2 × 2 tables.
Two investigators independently extracted patient and study characteristics, and differences were resolved by consensus.
Dewey and colleagues investigated 89 and 20 studies (comprising 7,516 and 989 patients) that assessed CT and MRI, respectively. Overall, a bivariate analysis of data yielded a mean sensitivity and specificity of 97.2 percent and 87.4 percent for CT and 87.1 percent and 70.3 percent for MRI.
In studies that included only patients with suspected CAD, the authors reported that the sensitivity and specificity of CT were 97.6 percent and 89.2 percent.
Notably, covariate analysis yielded a significantly higher sensitivity for CT scanners with more than 16 rows (98.1 percent) than for older-generation scanners (95.6 percent), according to the researchers. Also, heart rates less than 60 beats/min during CT yielded significantly better values for sensitivity than did higher heart rates. As a result, Dewey and colleagues noted that “scanners with more than 16 rows improve sensitivity, as do slowed heart rates.”
Included in their limitations, the authors acknowledged that fewer studies investigated coronary angiography with MRI, and only five studies were direct head-to-head comparisons of CT and MRI. Also, they wrote the “covariate analyses explained only part of the observed heterogeneity.”