Saremi Farhood, Pourzand Lila, Krishnan Subramaniam, Ashikyan Oganes, Gurudevan Swaminatha V, Narula Jagat, Kaushal Khushboo, Raney Aidan
Departments of Radiological Sciences and Cardiology, University of California, Irvine, University of California Medical Center, 101 The City Drive, Route 140, Orange, CA 92868-3298, USA.
Radiology. 2008 Jun;247(3):658-68. doi: 10.1148/radiol.2473070819.
To retrospectively evaluate the anatomic characteristics of the right atrial cavotricuspid isthmus (CTI) by using 64-section multi-detector row computed tomography (CT).
Institutional review board approval and waiver of informed consent were obtained for this HIPAA-compliant study. The anatomic region of the CTI was evaluated in 201 patients (116 men and 85 women; mean age, 58 years +/- 11 [standard deviation]) who underwent coronary multi-detector row CT. CTI length was assessed along three parallel isthmic levels (paraseptal, central, and inferolateral). Central isthmus depth was classified as straight (3 mm), concave (>3 to </=5 mm), or pouchlike (>5 mm). Measurements were obtained during three cardiac phases: midsystole, middiastole, and atrial contraction. Subthebesian recess dimensions and eustachian ridge width were measured. Distances from the atrioventricular node artery to the coronary sinus, from the right coronary artery (RCA) to the inferior vena cava, and from the RCA to the tricuspid valve annulus were measured. Software was used for statistical analysis.
At middiastole, the paraseptal isthmus (mean length, 20 mm +/- 3.5; range, 11-34 mm) was significantly shorter than the central isthmus (24 mm +/- 4.3; range, 12-43 mm) and the central isthmus was shorter than the inferolateral isthmus (27 mm +/- 4.8; range, 13-45 mm) (P < .001). The longest CTI measurements were obtained during midsystole, and the shortest were obtained during atrial contraction (40% variation per cardiac cycle). Isthmus contraction occurred primarily in the posterior segment of the central isthmus (RCA to inferior vena cava distance). At middiastole, the central isthmus was straight in 8% of patients, concave in 47% of patients, and pouchlike (>5 mm) in 45% of patients. The mean depth was greater during atrial contraction (6.3 mm +/- 2.1) than in midsystole (4.3 mm +/- 1.5) and middiastole (5.1 mm +/- 1.8) (32% variation during cardiac cycle). A subthebesian recess greater than 5 mm deep was identified in 45% of patients. In 24% of patients, a thick eustachian ridge greater than 4 mm was seen. The atrioventricular node artery passed close to the coronary sinus wall (mean distance, 2.1 mm +/- 0.7; range, 1-6 mm).
Cardiac multi-detector row CT provides extensive information regarding the size and morphology of the CTI and its related structures.
通过使用64层多排螺旋计算机断层扫描（CT）回顾性评估右心房腔静脉三尖瓣峡部（CTI）的解剖特征。
本符合健康保险流通与责任法案（HIPAA）的研究获得了机构审查委员会的批准并免除了知情同意。对201例行冠状动脉多排螺旋CT检查的患者（116例男性和85例女性；平均年龄58岁±11[标准差]）的CTI解剖区域进行评估。沿着三个平行的峡部层面（房间隔旁、中央和下外侧）评估CTI长度。中央峡部深度分为直线型（<3mm）、凹陷型（>3至≤5mm）或袋状（>5mm）。在三个心动周期阶段进行测量：收缩中期、舒张中期和心房收缩期。测量了心内膜下隐窝尺寸和下腔静脉瓣嵴宽度。测量了从房室结动脉到冠状窦、从右冠状动脉（RCA）到下腔静脉以及从RCA到三尖瓣环的距离。使用软件进行统计分析。
在舒张中期，房间隔旁峡部（平均长度20mm±3.5；范围11 - 34mm）明显短于中央峡部（24mm±4.3；范围12 - 43mm），且中央峡部短于下外侧峡部（27mm±4.8；范围13 - 45mm）（P <.001）。最长的CTI测量值在收缩中期获得，最短的在心房收缩期获得（每个心动周期变化40%）。峡部收缩主要发生在中央峡部的后段（RCA到下腔静脉的距离）。在舒张中期，8%的患者中央峡部为直线型，47%为凹陷型，45%为袋状（>5mm）。心房收缩期的平均深度（6.3mm±2.1）大于收缩中期（4.3mm±1.5）和舒张中期（5.1mm±1.8）（心动周期内变化32%）。45%的患者存在深度大于5mm的心内膜下隐窝。24%的患者可见厚度大于4mm的增厚下腔静脉瓣嵴。房室结动脉靠近冠状窦壁走行（平均距离2.1mm±0.7；范围为1 - 6mm）。
心脏多排螺旋CT提供了关于CTI及其相关结构的大小和形态的广泛信息。
