Jahnke Cosima, Paetsch Ingo, Nehrke Kay, Schnackenburg Bernhard, Gebker Rolf, Fleck Eckart, Nagel Eike
Department of Internal Medicine/Cardiology, German Heart Institute, Augustenburger Platz 1, 13353 Berlin, Germany.
Eur Heart J. 2005 Nov;26(21):2313-9. doi: 10.1093/eurheartj/ehi391. Epub 2005 Jun 29.
Current imaging of the coronary arteries with magnetic resonance coronary angiography (MRCA) is restricted to limited coverage of the coronary arterial tree and requires complex planning. We present and evaluate a rapid, single-scan MRCA approach with complete coverage of the coronary arterial tree.
Fifty-five consecutive patients with suspected coronary artery disease underwent free-breathing, navigator-gated MRCA using a single three-dimensional volume with transversal slice orientation and nearly isotropic spatial resolution (1.2 x 1.2 x 1.4 mm(3)) with coverage of the whole heart [steady-state free precession (SSFP); TR/TE/flip angle: 5.3 ms/2.6 ms/90 degrees ; Philips Intera CV 1.5T]. The acquisition duration per heart beat was individually adapted to the cardiac rest period. Correction of respiratory motion was done using a patient-specific affine prospective navigator technique (two navigator beams: cranio-caudal position on the dome of the right hemidiaphragm and anterior-posterior position on the right chest wall; gating window 10 mm). The diagnostic performance of MRCA in detecting significant coronary stenoses was evaluated against X-ray angiography as the standard of reference (32 patients) using a 16-segment model. Effective scan duration was 18+/-6 min (navigator efficiency: 68+/-14%). In all examinations, the main epicardial vessels [left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA)], including their distal segments and major side branches (number of visible side branches: LAD, 2.0+/-0.9; LCX, 1.5+/-0.6; RCA, 2.3+/-0.9), were reliably visualized. Eighty-three per cent of all coronary segments were evaluable; sensitivity, specificity, and diagnostic accuracy were 78, 91, and 89%, respectively.
The combination of an imaging sequence with an intrinsically high contrast (SSFP) and a sophisticated navigator technique (affine transformation) resulted in high quality, high resolution imaging of the whole coronary arterial tree within a short examination duration. Robustness and diagnostic accuracy may allow for a routine application in the near future.
目前磁共振冠状动脉造影（MRCA）对冠状动脉的成像仅限于冠状动脉树的有限覆盖范围，并且需要复杂的规划。我们提出并评估一种快速、单次扫描的MRCA方法，该方法可实现冠状动脉树的完整覆盖。
55例连续的疑似冠心病患者接受了自由呼吸、导航门控的MRCA检查，使用单个三维容积，其切片方向为横向，空间分辨率近乎各向同性（1.2×1.2×1.4 mm³），覆盖整个心脏[稳态自由进动（SSFP）；TR/TE/翻转角：5.3 ms/2.6 ms/90°；飞利浦Intera CV 1.5T]。每个心跳的采集持续时间根据心脏静息期进行个体化调整。使用患者特异性仿射前瞻性导航技术（两个导航束：右半膈肌穹窿的头-尾位置和右胸壁的前-后位置；门控窗口10 mm）进行呼吸运动校正。以X射线血管造影作为参考标准（32例患者），使用16段模型评估MRCA检测显著冠状动脉狭窄的诊断性能。有效扫描持续时间为18±6分钟（导航效率：68±14%）。在所有检查中，主要的心外膜血管[左前降支（LAD）、左旋支（LCX）和右冠状动脉（RCA）]，包括其远端节段和主要侧支（可见侧支数量：LAD，2.0±0.9；LCX，1.5±0.6；RCA，2.3±0.9）均能可靠显示。所有冠状动脉节段的83%可评估；敏感性、特异性和诊断准确性分别为78%、91%和89%。
具有固有高对比度的成像序列（SSFP）与先进的导航技术（仿射变换）相结合，在短检查时间内实现了整个冠状动脉树的高质量、高分辨率成像。其稳健性和诊断准确性可能使其在不久的将来得以常规应用。
