The Effect And Safety Of Spark Multi-electrode Radiofrequency Ablation Catheter Used To Inhibit Sympathetic Nervous System And Inflammatory Reaction In PVN Of DOCA Hypertension Pig Model

Background:Hypertension is the most common cardiovascular disease around the world.Resistant hypertension was defined as failure to achieve a guideline-driven blood pressure of less than 140/90 mmHg in patients who are adherent to maximally tolerated doses of at least three antihypertensive drugs,including a diuretic appropriate for kidney function.Meanwhile it has been proved that hypertension is a persistent state of inflammation and excessive sympathetic nervous system.This study was aimed to prove the inhibition of inflammatory reaction and sympathetic nervous system after renal artery denervation(RDN)with Spark catheter.We also evaluate the safety of Spark ablation catheter through OCT examination.Methods:PART-1&PART-2:12 pigs were enrolled in this experiment.All pigs were divided into 3 groups(Control group,DOCA-hypertension sham group,DOCA-hypertension RDN group).RDN was carried out with Spark ablation catheter twice in each renal artery(5W,55℃,90s).Mean artery blood pressure(MAP)were measure 1 month later.All pigs were sacrificed 1 month after procedure.Fos-B and c-Fos in PVN were tested by fluoroimmunoassay;NF-кB p65 in PVN were tested by Western blot;IL-6 and TNF-αin PVN were tested by Elisa.PART-3:8 normal pigs were enrolled in this experiment.Renal artery angiography and OCT were performed before,immediately after,1 month after RDN.All data were analyzed by SPSS 22.0.Results:MAP in DOCA-hypertension RDN group significantly reduced1 month after procedure(141.25±2.60 vs 120.38±2.46,P<0.001).NF-кB p65 expression in PVN was significantly lower in DOCA-hypertension RDN group compared with DOCA-hypertension sham group(6.05±0.61vs 1.59±0.13,P<0.001).IL-6 expression in PVN was significantly lower in DOCA-hypertension RDN group compared with DOCA-hypertension sham group(4.52±0.32 vs 9.60±1.81,P=0.009).TNF-αexpression in PVN was significantly lower in DOCA-hypertension RDN group compared with DOCA-hypertension sham group(10.92±0.51 vs1.37±1.02,P<0.001).c-Fos(8.03±0.69 vs 15.75±1.47,P=0.011)and Fos-B(16.70±0.49 vs 37.52±0.70,P<0.001)expression were also significantly lower in DOCA-hypertension RDN group compared with DOCA-hypertension sham group.Renal artery angiography results showed 100%artery spasm after RDN(100%vs 0%,X~2=28,P<0.001).OCT results showed artery edema(64.3%vs 7.1%,X~2=9.950,P=0.002)and thrombus formation(42.9%vs 0%,X~2=7.636,P=0.006)were significant immediately after procedure.1 month later,OCT showed no artery complication(P>0.05).Conclusion:Spark ablation catheter was proved effective to reduce the MAP of DOCA-hypertension pig model.Meanwhile it contributes to inhibition of inflammatory reaction and sympathetic nervous system in PVN.OCT results showed this ablation catheter was safe for RDN.