Cardiol J. 2013;20(3):235-40. doi: 10.5603/CJ.2013.0067.
The anatomical variants of the relations of the left circumflex artery (LCx) andthe coronary sinus (CS) determine the safety of percutaneous mitral annuloplasty (PMA) as an occlusion of the LCx and its consequences might occur in some cases. Thus, knowledge ofthe anatomy of cardiac anatomy and any variations are important for surgeons.
In 320 (126 women, age 59 ± 11) patients, a 64-slice computed tomography (MSCT) (Aquilion 64) was performed due to a suspicion of coronary artery disease. A scanwith ECG-gating was performed using a slice thickness of 0.5 mm during a breath-hold. The helical pitch was 12.8, rotation time: 0.4 s and average tube voltage: 135 kV at 380 mA.100 mL of non-ionic contrast agent was given in three phases at an average rate of 4.5 mL/s.In each case, ten 3D volume rendering and 2D multiplanar reconstructions of the vessels were created (Vitrea 2).
The CS was visualized in all cases and the LCx in 315 (98.4%). In 302 (95.8%)cases, the CS was the dominant vessel; in 10 (3.17%) cases both vessels were equal and the LCxwas dominant in only 3 (0.9%) cases. 52 anatomical variants were identified; 3 of them werethe most common (in 164/315 cases; 50.8%). The CS usually lies above the atrioventricular(AV) sulcus (239-75.9%) and the LCx within the AV sulcus (173-54.9%). In 235 (74.6%)cases, the LCx was closer (than the CS) to the mitral valve. It was found that in 78 (24.7%) cases, the LCx was beneath the CS in selected phases (a risk of LCx occlusion by a PMA device).The LCx closer to the mitral valve, which is considered as a safe feature for PMA, was observed in only 75 (23.8%) of the cases. The most dangerous pattern was found in 19 cases(6.1%) - 2 or 3 CS/LCx crosses.
The huge anatomical variability of the anatomy of the CS/LCx strengthens the role of MSCT before PMA implantation.
左回旋支（LCx）与冠状窦（CS）关系的解剖变异决定了经皮二尖瓣环成形术（PMA）的安全性，因为在某些情况下 LCx 的闭塞及其后果可能会发生。因此，了解心脏解剖结构及其任何变异对于外科医生来说非常重要。
在 320 例（126 例女性，年龄 59±11 岁）疑似冠状动脉疾病的患者中，进行了 64 层计算机断层扫描（MSCT）（Aquilion 64）。使用心电门控进行扫描，在屏气时使用 0.5 毫米的切片厚度。螺旋螺距为 12.8，旋转时间为 0.4 秒，平均管电压为 380mA 时为 135kV。以平均 4.5mL/s 的速度分三个阶段给予 100mL 非离子型造影剂。在每种情况下，都创建了十个血管的 3D 容积渲染和 2D 多平面重建（Vitrea 2）。
所有病例均显示 CS，315 例（98.4%）显示 LCx。在 302 例（95.8%）中，CS 是优势血管；在 10 例（3.17%）中，两个血管相等，仅在 3 例（0.9%）中 LCx 占优势。确定了 52 种解剖变异；其中 3 种最常见（在 164/315 例中；50.8%）。CS 通常位于房室（AV）沟上方（239-75.9%），LCx 在 AV 沟内（173-54.9%）。在 235 例（74.6%）中，LCx 更接近（与 CS 相比）二尖瓣。发现 78 例（24.7%）在选定的阶段 LCx 位于 CS 下方（PMA 装置可能导致 LCx 闭塞的风险）。仅在 75 例（23.8%）中观察到更接近二尖瓣的 LCx，这被认为是 PMA 的安全特征。在 19 例（6.1%）中发现了最危险的模式 - 2 或 3 个 CS/LCx 交叉。
CS/LCx 解剖结构的巨大解剖变异性增强了 PMA 植入前 MSCT 的作用。
