[Feasibility of Non-contrast-enhanced Coronary Magnetic Resonance Angiography at 3.0T]

Objective To evaluate the feasibility of non-contrast-enhanced magnetic resonance angiography (NCE-MRA) on a 3.0T scanner. Methods Totally 36 volunteers and 24 patients with clinically suspected coronary artery disease underwent NCE-MRA. The quality of the NCE-MRA images was graded for each segment on a four-point scale. The subjects were divided into two groups according to image quality. The age,body mass index (BMI),heart rate,end-expiratory diaphragm displacement,and respiratory diaphragm motion amplitude were evaluated and compared. Results The average image quality score of every segment was above 2 points. The proximal and middle segments of left anterior descending artery had significantly higher quality scores than the distal segments (P=0.000) and the proximal segment of left circumflex coronary artery had significantly higher quality scores than the distal segments (P=0.000),the proximal segment of right coronary artery also had a significant higher quality score than its distal segment (P=0.001). The image quality was good in 38 subjects (64.4%). The heart rate [(66.35±9.39) beat/min vs. (75.32±11.67) beat/min] (P=0.002) and the body mass index [(24.72±3.33) kg/m ² vs. (27.82±3.61) kg/m ²] (P=0.002) were significantly different between the good image quality group and the poor image quality group. The end-expiratory diaphragm displacement in good image quality group was (4.43±2.07)mm,which was significantly lower than that in poor image quality group [(9.26±7.62)mm](P=0.013). The respiratory diaphragm motion amplitude [(21.35±6.02) mm] in good image quality group was significantly lower than that in poor image quality group [(30.68±14.20)mm](P=0.012). Conclusion NCE-MRA on 3.0T is a feasible tool for visualization of the proximal and middle segments of coronary arteries,and the image quality can be optimized by controlling heart rate and respiration in the future.