| Background. Atrial fibrillation (AF) is a common arrhythmia clinically, with morbidity of 0.4-0.9% among the whole population. During this arrhythmia, the atrial function of pumping blood into ventricles is eliminated, and the complication of embolism is significantly increased. Up to now the treatment for AF is far from ideal. It is observed clinically that paroxysmal AF tends to develop into persistent AF. Although the rate of this change is related to the etiology of the primary disease, it is related to the AF itself as well. AF would often recur after the cardioversion into sinus rhythm, whether by chemical or by electrical defibrillation, and the recurrence is positively related to the persisting period of AF. The hypothesis of "AF begets AF" was first proposed by Wijffels in 1995, and it was proven by animal experiments. The concept of "Atrial Electrical Remodeling" was established by the same author, and was proven and accepted by many clinicians later. The mechanism was studied, in which the L-type calcium channel was thought to play an important role. The clinical influence of the theory of electrical remodeling is: that defibrillation should be performed as early as possible so that the extent of electrical remodeling would be reduced, and a new idea for AF chemical therapy was provided.The present study was designed to test the phenomenon and mechanism of atrial electrical remodeling in lab animals.Methods: Eight sheeps, auto-randomized controlled, were divided into four groups, in which each sheep was tested four times. The grouping was as below: rapid pacing alone; the other group consist of rapid pacing after administration of verapamil; calcium gluconate; and verapamil + calcium gluconate, respectively. The pentobarbital-anesthetized sheeps underwent insertion of two sheaths into internal jugular vein, through which one catheter was placed in the right atrial appendage for pacing, and another catheter was placed in His-bundle for recording...
|
PDF Full Text Request