[The relationship of paroxysmal atrial fibrillation and regional sympathetic innervations in the atria and pulmonary veins: experiment with dogs].
OBJECTIVE
To test the hypothesis that regional sympathetic innervation in the atria and pulmonary veins are correlated with atrial fibrillation (AF).


METHODS
Sixteen adult mongrel dogs underwent thoracotomy under general anesthesia. Bilateral cervical vagal trunks were decentralized. Multipolar catheters were placed into right atrial appendage (RAA), left atrial appendage (LAA), left atrium (LA), left superior pulmonary vein (LSPV), left inferior pulmonary vein (LIPV), right superior pulmonary vein (RSPV), and left inferior pulmonary vein (LIPV). The bilateral sympathovagal trunks were stimulated, S1S1 burst stimulation and S1S2 stimulation procedure were performed on different points of RAA, LAA, LA, LSPV, LIPV, RSPV, and LIPV. The TF thus induced was monitored. After that, the dogs were killed with their hearts and lungs were taken out. Immunocytochemical staining of cardiac nerves was performed using anti-tyrosine hydroxylase (TH) antibodies. The nerve fiber density was counted manually for each case and expressed as the mean number per slice.


RESULTS
Two dogs died during the experiment and the whole procedure was completed on 14 dogs. There was no significant difference in the AF induction rate among the most points, however, the AF induction rate of the RIPV was significantly lower than those of the other points (all P < 0.05). The levels of density of TH-positive nerves in the atria and atrial appendages were significantly higher than those in the pulmonary veins (P = 0.02). The density of TH-positive nerves in the dogs with AF was significantly higher than that in the dog without AF (P < 0.05). The innervation of sympathetic nerves in atria and pulmonary veins was highly correlated to the induction of atrial fibrillation (r = 0.83).


CONCLUSIONS
Regional sympathetic hyperinnervation plays an important role in atrial fibrillation induction.
Yi
Zhong
Z
Department of Cardiology, People's Hospital, Peking University, Beijing 100044, China.
Zhang
Hai-cheng
HC
Zhang
Ping
P
Liu
Gang
G
Lu
Peng
P
Sun
Jian-ling
JL
Liu
Bin
B
Guo
Ji-hong
JH
D000818:Animals; D001281:Atrial Fibrillation / Q000503:physiopathology*; D004285:Dogs; D004558:Electric Stimulation; D006321:Heart / Q000294:innervation*; D006325:Heart Atria / Q000201:enzymology / Q000294:innervation; D007150:Immunohistochemistry; D008297:Male; D009412:Nerve Fibers / Q000502:physiology; D011667:Pulmonary Veins / Q000201:enzymology / Q000294:innervation*; D013564:Sympathetic Nervous System / Q000502:physiology*; D013908:Thoracotomy; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D014446:Tyrosine 3-Monooxygenase