[The role of coronary sinus musculature on electrical conduction between left atrium and right atrium in isolated canine heart].
OBJECTIVE
To investigate electrophysiological characteristics of the coronary sinus musculature and explore its role on electrical conduction between left atrium and right atrium in isolated canine heart.


METHODS
The electrical connections between coronary sinus, left atrium and right atrium were detected by programmed stimulation delivered at coronary sinus ostium, distal coronary sinus and lateral wall of left atrium in a Langendorff model of canine.


RESULTS
During stimulation delivered at coronary sinus ostium and distal coronary sinus, posterior wall of left atrium was firstly activated by electronic signal through coronary sinus musculature, the conduct time of coronary sinus ostium stimulation and distal coronary sinus stimulation were (44 +/- 21) ms and (41 +/- 15) ms, respectively. During stimulation delivered at lateral wall of left atrium, electronic signal was firstly observed in coronary sinus. During premature stimulation, conduction blockade of coronary sinus to left atrium was evidenced in parts of hearts, but electronic conduction of left atrium to right atrium remained stable. The ERP at the different stimulation sites of coronary sinus ostium and distal coronary sinus, posterior wall of left atrium were (122 +/- 19) ms, (114 +/- 12) ms (n = 3) and (107 +/- 17) ms (all P > 0.05).


CONCLUSIONS
A conduction way connecting left and right atria exists in coronary sinus which might play an important role on inducing and maintaining atrial arrhythmias under certain pathological conditions.
Chen
Fang
F
Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, China.
Yang
Sha-Ning
SN
Wang
Teng
T
D000818:Animals; D054326:Coronary Sinus / Q000502:physiology*; D004285:Dogs; D006325:Heart Atria; D006329:Heart Conduction System / Q000502:physiology*; D008297:Male; D009206:Myocardium