An improved in vivo method for atrioventricular node ablation via thoracotomy

Brazilian Journal of Medical and Biological Research

R.h. Maciver²  R.d. Stewart²  C.l. Backer²  S. Tsao¹  D.a. Harrington²  C. Mavroudis² 

[1] ,Northwestern University Feinberg School of Medicine Division of Cardiovascular-Thoracic Surgery

关键词: Atrioventricular node;    Heart block;    Ablation;    Tissue engineering;    Regenerative medicine;    In vivo model;   

DOI  :  10.1590/S0100-879X2010005000003

来源: SciELO

【 摘 要 】

The atrioventricular (AV) node is permanently damaged in approximately 3% of congenital heart surgery operations, requiring implantation of a permanent pacemaker. Improvements in pacemaker design and in alternative treatment modalities require an effective in vivo model of complete heart block (CHB) before testing can be performed in humans. Such a model should enable accurate, reliable, and detectable induction of the surgical pathology. Through our laboratory’s efforts in developing a tissue engineering therapy for CHB, we describe here an improved in vivo model for inducing chronic AV block. The method employs a right thoracotomy in the adult rabbit, from which the right atrial appendage may be retracted to expose an access channel for the AV node. A novel injection device was designed, which both physically restricts needle depth and provides electrical information via electrocardiogram interface. This combination of features provides real-time guidance to the researcher for confirming contact with the AV node, and documents its ablation upon formalin injection. While all animals tested could be induced to acute AV block, those with ECG guidance were more likely to maintain chronic heart block >12 h. Our model enables the researcher to reproduce both CHB and the associated peripheral fibrosis that would be present in an open congenital heart surgery, and which would inevitably impact the design and utility of a tissue engineered AV node replacement.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License