Department of Morphology, Faculty of Medicine, Federal University of Ceará, Street Delmiro de Farias s/n, Rodolfo-Teófilo Zip code: 60.430-170, Ceará, Fortaleza, Brazil.
Department of Morphology, Faculty of Medicine, Federal University of Ceará, Street Delmiro de Farias s/n, Rodolfo-Teófilo Zip code: 60.430-170, Ceará, Fortaleza, Brazil; Postgraduation Program in Morphofunctional Sciences, Federal University of Ceará, Ceará, Fortaleza, Brazil.
Morphologie. 2020 Sep;104(346):182-186. doi: 10.1016/j.morpho.2020.03.003. Epub 2020 Apr 16.
Performing surgical procedures around the mitral valve (MV) annulus can cause iatrogenic lesions on the circumflex artery (Cx). The risk of this iatrogenesis comes from the proximity between this vessel and the MV annulus.
To evaluate the relation between the MV annulus and the Cx at different spots of its path and highlight the risks of its damage.
Fifty cadaveric adult human hearts were studied. Each heart was categorized depending on coronary dominance, and Cx was classified in type 1 (Cx giving off only the left posterior ventricular artery) and type 2 (Cx reaching the crux cordis and giving off the posterior interventricular branch). Three reference spots were chosen: A- when Cx begins to run across the coronary sulcus; B- immediately before the left posterior ventricular artery emerges and C- in the midpoint of the two previous points; to measure the diameter of the Cx and the MV annulus. Values of P<0.05 were considered significant.
A total of 43 (86%) hearts were classified in type 1. These hearts showed that the diameter of the Cx in spot A is bigger than in the B and C spots (P=0.001). The 7 hearts (14%) classified in type 2 did not exhibit a difference in the diameter of the Cx in the A, B and C spots (NS). Also, the thickness of the fibrous annulus, in type 1 and type 2 hearts were not different between the three spots (NS).
The present study showed that the diameter of the Cx varies depending on the heart type. This knowledge might improve the success rate of cardiac surgeries and decrease the rates of iatrogenic Cx lesions.
在二尖瓣（MV）环周围进行手术操作可能会导致回旋支（Cx）发生医源性损伤。这种医源性损伤的风险来自于该血管与 MV 环的接近程度。
评估 MV 环与 Cx 在其路径不同部位的关系，并强调其损伤的风险。
研究了 50 例成人尸体心脏。根据冠状动脉优势将每颗心脏进行分类，并将 Cx 分为 1 型（仅发出左后心室动脉的 Cx）和 2 型（到达心尖并发出后间隔分支的 Cx）。选择了 3 个参考点：A-当 Cx 开始穿过冠状沟时；B-左后心室动脉出现之前；C-在前两个点的中点；以测量 Cx 和 MV 环的直径。P<0.05 被认为有统计学意义。
共有 43 颗（86%）心脏被归类为 1 型。这些心脏表明，在 A 点 Cx 的直径大于 B 和 C 点（P=0.001）。7 颗（14%）归类为 2 型的心脏在 A、B 和 C 点的 Cx 直径没有差异（NS）。此外，1 型和 2 型心脏的纤维环厚度在三个点之间没有差异（NS）。
本研究表明，Cx 的直径取决于心脏类型。这些知识可能会提高心脏手术的成功率，降低医源性 Cx 损伤的发生率。
