ABSTRACT
Objective:To observe the influence of radiofrequency catheter ablation of the fat pad at the right pulmonary vein- atria junction(RPV fat pad)on Bezold-Jarisch reflex(BJR)induced by veratridine in canine.Methods:Ten mongrel dogs were anesthetized and their chest were opened through a right thoracotomy to expose the RPV fat pad.Veratridine was injected into the left ventricle at bolus doses of 10?g/kg through a catheter to induce BJR.The sinus cycle length(SCL),systolic arterial pressure(SAP),diastolic arterial pressure(DAP),mean arterial pressure(MAP),left ventricle systolic pressure(LVSP), left ventricle diastolic pressure(LVDP)and mean left ventricle pressure(MLVP)were measured under the baseline and after ablation of the RPV fat pad;the changes of the above parameters(?SCL,?SAP,?DAP,?MAP,?LVSP,?LVDP,and?MLVP)were calculated.Then the same dose of veratridine was injected under the pad after ablation and the changes of the a- bove parameters were observed.Results:BJR was successfully induced in the 8 animals;the animals has prolonged sinus cycle length(SCL)and decreased MAP and MLVP.After ablation,the prolongation of SCL after injection of veratridine was markedly reduced([229.2?92.3]ms vs[39.3?14.1]ms,P