Objective:To investigate effects and reliability of catheter radiofrequency ablation of frequent ventricular premature beats(VPBs) originating from the right ventricular outflow tract(RVOT).Methods:32 patients with frequent VPBs originating from RVOT were randomly divided into conventional mapping group(16 patients) and coronary sinus electrode mapping group(16 patients).They were ablated with conventional metheds.During follow-up 22?14 months,radiofrequency ablation short-term successful rate and long-term successful rate,reliability,and the clinical symptoms were recorded.Mapping duration was compared between conventional mapping group and coronary sinus electrode mapping group.Results:(1)Radiofrequency ablation short-term successful and long-term successful rate were 100%,93.8% respectively.No complications occurred.The clinical symptoms caused by VPBs disappeared after successful ablation.(2)Mapping duration of coronary sinus electrode mapping group was shorter than that of conventional mapping group.Conclusion:Successful rate and reliability of radiofrequency ablation of VPBs originating from RVOT were higher.Mapping duration was decreased by smart application of conventional catheter,in other words,X-ray radiation energy was decreased.

Objective:To measure the cardiac vagus nerve activity and its circadian rhythm in patients with essential hypertension(EH group) and normontensive controls (NC group),and to study the relationship between the cardiac vagus nerve activity and blood pressure.Methods:By dynamic electrocardiogram and ambulatory blood pressure monitoring,HF,PNN 50 and their circadian rhythm were compared between the EH group and NC group,and the relationship between HF,PNN 50 and blood pressure was analyzed.Results:During 24 hours,waking and sleeping hours,HF,PNN 50 were significantly lower(P

0.05).②To be compared with the condition before balloon inflation,p wave dispersion during balloon inflation were significantly higher in the myocardial ischaemia groups(36.7?5.70 vs 46.3?4.21ms,36.9?4.59vs44.7?6.47ms,36.4?4.76vs44.8?5.88ms, P 0.05).Conclusion:The prolongation of p wave dispersion may be a marker for severe acute myocardial ischaemia.

Objective:To investigate the efficacy and safety of catheter radiofrequency ablation for focal atrial tachycardia,by comparing conventional mapping group and Carto system mapping group.Methods:50 patients with focal atrial tachycardia underwent electrophysiologic study and radiofrequency ablation.32 cases were in conventional mapping group,and 25 cases in Carto system mapping group,including 7 cases with unsuccessful ablation in conventional mapping group.During follow-up 20?11 months,radiofrequency ablation acute successful rate,long-term successful rate,safety,and the clinical symptoms were recorded.ⅹ-ray radiation exposure time was compared between conventional mapping group and Carto system mapping group.Results: ① radiofrequency ablation acute successful rate of conventional mapping group and Carto system mapping group were 78% and 100%,and long-term successful rate were 68% and 96% respectively.No complications occurred.The clinical symptoms caused by focal atrial tachycardia disappeared after successful ablation.② ⅹ-ray radiation exposure time of Carto system mapping group was shorter than that of conventional mapping group.Conclusions: Successful rate and safety of radiofrequency ablation of focal atrial tachycardia were higher,and effects of Carto system mapping group were better than those of conventional mapping group.And X-ray radiation exposure time of Carto system mapping group decreased.

Objective:To evaluate the safety and efficacy of cooled radiofrequency(RF)ablation for arrhythmias by saline irrigation catheter.Methods:Twenty-six patients with arrhythmia underwent cooled RF ablation by saline irrigation catheter after failure of conventional catheter RF ablation.5cases were with a right-and 1 case with a left-sided resistant accessory pathway,5 cases were with atrial tachycardia,5cases with typeⅠatrial flutter,6 cases with paroxysmal atrial fibrillation,and 4 cases with idiopathic ventricular tachycardia.The ablation parameters were compared between saline irrigation catheter RF ablation and conventional catheter RF ablation.The safety and efficacy of cooled RF ablation by saline irrigation were recored and the average duration of follow-up was 15.8?7.5 months.Results:①There were higher peak electrode temperature,impedance,and lower RF power with conventional catheter electrode than with saline irrigation electrode,and there was no difference in the ablation duration.②Acute successful rate of cooled RF ablation by saline irrigation was 100%(26/26),and long-time successful rate was 88.5%(23/26).③A stroke occurred in 1case,and eschar formed on the catheter electrode in 6 cases with conventional catheter electrode.No complications occurred with saline irrigation electrode.Conclusions:Cooled RF ablation by saline irrigation catheter had good efficacy and high safety in treating arrhythmias,especially for those located deep.

Objective:To investigate the efficacy and safety of catheter radiofrequency ablation for ventricular tachycardia.Methods:Thirty-three patients with ventricular tachycardia were performed electrophysiologic study and radiofrequency ablation.Thirty cases with idiopathic ventricular tachycardia underwent pacemapping and/or activation mapping,and 3cases with arrhyththmogenic right ventricular cardiomyopathy underwent Carto system mapping.During the average follow-up of 28?17 months,acute successful rate and long-term successful rate of radiofrequency ablation were recorded ,and safety was observed.Rsults:①For radiofrequency ablation,the acute successful rate was 90.9%(30/33),and 3 cases without successful ablation were with idiopathic ventricular tachycardia;long-time successful rate was 87.9%(29/33),and 1 case with arrhyththmogenic right ventricular cardiomyopathy reoccurred.②Ventricular responses were induced by radiofrequency ablation in all successful cases.③No complication occurred.Conclusions:Successful rate and safety of radiofrequency ablation for ventricular tachycardia were high;and the ventricular responses during ablation could be the predictors for successful ablation.

Objective: The compare the safety and efficacy between cryoablation (CRYO) and radiofrequency catheter ablation (RFCA) for treating the patients with atrio-ventricular nodal reentrant tachycardia (AVNRT) by meta-analysis.
Methods: We systemically searched the Medline, Cochrane library and Embase database to fulifll our pre-deifned criteria until the publication of May 2014.
Results: There were 5 randomized controlled trials (RCTs) and 14 retrospective trials enrolled in our study with 2900 patients. The patients were allocated into 2 groups:CRYO group, n=1384 and RFCA group, n=1516. The overall pool-analysis demonstrated that compared with RFCA group, CRYO group had the lower risk of permanent atrio-ventricular nodal block (OR:0.27, 95%CI 0.11 to 0.62, P<0.01) and shorter X-ray exposure time (WMD:-3.36, 95%CI-5.58 to-1.15, P<0.01);while CRYO group had the lower immediate procedural success rate (OR:0.63, 95%CI 0.42 to 0.96, P<0.05), longer procedural time (WMD:10.97, 95%CI 3.35 to 18.58, P<0.01), and higher long-term arrhythmia recurrence rate (OR:2.89, 95%CI 2.05 to 4.06, P<0.01).
Conclusion: Although CRYO could decrease the risk of permanent atrio-ventricular nodal block, while its effectiveness was lower than RFCA for AVNRT treatment in relevant patients.

Objective:To compare the efficacy and safety between cryoablation(Cryo)and radiofrequency (RF)ablation in patients with atrioventricular nodal reentrant tachycardia(AVNRT). Methods: A total of 83 patients with AVNRT underwent electrophysiological treatment in our hospital from October 2006 to March 2009 were studied. Patients were divided into two groups according to their own choices. Cryo group (n=41) and RF group (n=42). The clinical characteristics,success rate,procedural time and ablative time were compared between two groups. Results:The procedural time and ablative time in Cryo group was significantly longer than those in RF group (119.14±40.16 min vs.85.86±28.24 min,P=0.001; 1118.91±620.62 s vs.370.97±279.23 s,P<0.001). The acute success rate was achieved in 40/41(97.6%)patients in Cryo group,and 42/42(100.0%) in RF group. Transient AV-block was encountered in 6 (15%) patients in the Cryo group and 5 (11.9%) in RF group (P=0.681). There was no complete atrial-ventricular(AV)conduction block at the end of procedures. There was no recurrence of AVNRT in either Cryo group nor in RF group during 11.6±5.5 months of follow up period.Conclusion:Cryoablation was as effective and safe as RF ablation for AVNRT. Cryo-energy was one kind of alternative ablation energy for AVNRT.