Kawashima Tomokazu
Department of Anatomy, Toho University, Ota-ku, Tokyo, Japan
Open Heart. 2025 Sep 11;12(2):e003520. doi: 10.1136/openhrt-2025-003520.
Transient or permanent iatrogenic conduction disturbances from injury to arteries supplying the cardiac conduction system (CCS) have increased. A more comprehensive understanding of CCS arterial anatomy is essential for advancing electrophysiological studies. Compared with the sinus node (SN) artery, atrioventricular node (AVN) artery is more variable and difficult to identify because of the thicker surrounding myocardium. Arterial sources other than the main AVN artery branching near the cardiac crux-such as the Bonapace's septal branch or Kugel's collateral artery-have often been overlooked or regarded as atypical and remain poorly characterised.
An alternative origin and course of the AVN artery were examined in 116 hearts via microdissection and in 14 additional hearts using serial histological sections of physiologically aged hearts without coronary artery occlusion.
An additional descending AVN artery was observed in 22.4% of cases and an interatrial septal branch extending to Koch's triangle was found in 11.2% based on the macroscopic analysis-findings aligning well with the histologically verified incidence of 35.7%. These results suggest that approximately one-third of individuals exhibit an additional descending AVN artery with features resembling the normal Bonapace's septal branch. Notably, this additional artery originates from a common trunk with the SN artery and Bachmann's bundle branches, forming an arterial complex supplying the proximal conduction components.
Using a large sample size, our findings highlight the anatomical and clinical importance of the arterial complex supplying the proximal conduction components, including the additional descending AVN artery. This arterial complex may include the Bonapace's septal branch and serve as a Kugel's collateral route in coronary occlusion. This characterisation provides basic essential anatomical data to support future research on iatrogenic conduction disturbances.
因损伤供应心脏传导系统（CCS）的动脉而导致的短暂性或永久性医源性传导障碍有所增加。更全面地了解CCS动脉解剖结构对于推进电生理研究至关重要。与窦房结（SN）动脉相比，房室结（AVN）动脉的变异更大，且由于周围心肌较厚而难以识别。除了在心脏十字交叉附近分支的主要AVN动脉之外的动脉来源，如博纳佩斯间隔支或库格尔侧支动脉，常常被忽视或视为非典型，其特征仍不明确。
通过显微解剖对116颗心脏的AVN动脉的另一种起源和走行进行了检查，并使用无冠状动脉闭塞的生理性老化心脏的连续组织切片对另外14颗心脏进行了检查。
基于宏观分析，在22.4%的病例中观察到一条额外的下行AVN动脉，在11.2%的病例中发现一条延伸至科赫三角的房间隔支，这些结果与组织学证实的35.7%的发生率非常吻合。这些结果表明，约三分之一的个体表现出一条额外的下行AVN动脉，其特征类似于正常的博纳佩斯间隔支。值得注意的是，这条额外的动脉起源于与SN动脉和巴赫曼束支的共同主干，形成一个供应近端传导成分的动脉复合体。
通过大样本量研究，我们的发现突出了供应近端传导成分的动脉复合体（包括额外的下行AVN动脉）的解剖学和临床重要性。这个动脉复合体可能包括博纳佩斯间隔支，并在冠状动脉闭塞时作为库格尔侧支途径。这一特征提供了基本的重要解剖学数据，以支持未来关于医源性传导障碍的研究。
