| PurposeTo preliminary evaluate the feasibility and the clinical value of the whole heartmagnetic resonance coronary angiography at 3.0 Tesla.Method and MaterialsBy using a three dimensional segmented k-space gradient echo imaging sequence(turbo field echo) with free breathing, the whole-heart MRCA and target-volumeMRCA were performed in 22 healthy volunteers.By using Soap Bubble-Tool, we obtain the length of visualized visible vessel,signal-to-noise ratio(SNR),contrast-to noise ratio (CNR) in LM/LAD, RCA, LCX..Analysis of image quality was performed on a segment-by-segment basis by usingthe coronary MR angiography source images. The following nine coronary segments:the LM coronary artery; the proximal segment of the LAD artery, the middle segmentof the LAD artery, the distal segment of the LAD artery; the proximal segment of theRCA artery, the middle segment of the RCA artery, the distal segment of the RCAartery; the proximal segment of the LCX artery, the distal segment of the LCX artery.By using the grade of 0-4 score, discrepancies between experienced radiologist inimage quality were resolved by consensus to establish a final consensus results.To preliminary evaluate the feasibility of the whole heart magnetic resonance coronaryangiography at 3.0 Tesla, the length of vessel,signal-to-noise ratio(SNR),contrast-to noise ratio(CNR) and imaging quality were compared separately. The whole-heart MRCA were performed in30 patients suspected of having coronary artery disease, 19 of them to undergo elective coronary angiography. Sensitivity, specificity, positive predictive value, and negative predictive value werecalculated for detection of significant stenosis(50％) using CAG as reference and gold standard.Results20 healthy volunteers completed successfully the whole-heart MRCA andtarget-volume MRCA in 22 healthy volunteers. Whole-Heart MRCA visualized RCA(10.41±2.37mm) and LM/LAD (8.47±1.40mm) over a significantly longer distancethan target-volume MRCA (9.82±1.44cm and 8.24±0.85cm),(P＜0.05);the visualizedvessel length for LCX in two approaches was not different(4.75±0.86cm and 4.65±0.91cm), (P＞0.05). SNR and CNR of whole-heart MRCA and target-volume MRCAwere not significantly different. Whole-heart MRCA showed higher image quality inthe distal segments of RCA and LAD (3.1±1.0 and 2.8±1.1) than the target-volumeMRCA (2.5±1.2 and 2.5±1.2), (P＜0.05); the other segments image quality werenot significantly different.To the healthy volunteers of whole-heart MRCA, seven segments is zeroscore,, twelve segments is one score, rate of diagnostic value is 86％(116/135). To thehealthy volunteers of target-volume MRCA, sixteen segments is zero score, elevensegments is one score, rate of diagnostic value is 80％(108/135). To the patientssuspected of having coronary artery disease of whole-heart MRCA, ten segments iszero score, twenty-five segments is one score, rate of diagnostic value is 85.5％(208/243).Whole-heart coronary MRA was completed in 27(84.5％)of 30 patients, 19 of them to undergoelective coronary angiography. Sensitivity, specificity, positive predictive value, and negativepredictive value of MRA in detecting significant stenosis were 73.91％, 82.29％,70.83％,87.88％using CAG as reference and gold standard.Conclusion3.0 T whole-heart MRCA is feasible; whole-heart MRCA in visualized coronary distalsegments is superior than target-volume MRCA. Free breathing whole heart coronary MRangiography with a navigator gated allows for the accurate detection of coronary artery stenosis noninvasively. CMRA showed high negative predictive value, which is useful for excludingcoronary stenosis in symptomatic patients.
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