Comparison of His-purkinje bundle pacing and right ventricular inflow tract septal pacing in the elderly

Objective To compare the short-term clinical effect and electrical parameters of His-purkinje bundle pacing(HPBP) and right ventricular inflow tract septal pacing(RVIP) in the elderly. Methods Between April 2017 and September 2019, sixty patients with indications for permanent cardiac pacing and resynchronization therapy in Beijing Anzhen Hospital were divided into the HPBP and RVIP groups, and were analyzed. A ventricular pacing lead was implanted in left ventricular septal sites with left bundle potentials or His potentials in the HPBP group. The lead was placed in right ventricular inflow tract septal sites close to distal His-bundle regions without potentials from the His-purkinje conduction system in the RVIP group. Lead impedance, R wave amplitude, pacing thresholds, QRS duration, left ventricular ejection fraction(LVEF), and left ventricular end-diastolic diameter(LVEDD), mitral regurgitation area reflux, QTc, T wave directivity, Tp-e and Tp-e/QT ratio were compared between the HPBP and RVIP groups during the procedure and the short-month follow-up. Results No significant differences were found in lead impedance, R wave amplitude, QRS duration, LVEF, LVEDD, mitral regurgitation area reflux, QTc, T wave directivity, Tp-e and Tp-e/QT ratio between the HPBP and RVIP groups. However, the pacing threshold was significantly lower in the HPBP group than in the RVIP group(0.7 ± 0.2 vs. 0.9 ± 0.3 V, P = 0.02). Conclusions The efficacy and electrical parameters of HPBP is comparable with RVIP during the procedure and the short-term follow-up.

Initial experience with ablation of the innervation surrounding sinus and atrioventricular nodes to treat paroxysmal bradyarrhythmia

Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure.The present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular(AV)nodes for treating patients with bradyarrhythmia.Methods:A total of 13 patients with cardiogenic syncope were included from May 2008 to June 2015.Under the guidance of fluoroscopy and/or three-dimensional geometry by 64-slice spiral computed tomography,atrial activation sequence in sinus rhythm was mapped.Chamber geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology(RMT)system.Cardioneuroablation was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus rhythm.Areas surrounding the sinus node,AV node,and the phrenic nerve were avoided.Results:Thirteen patients completed the studies.Ablation was successfully performed in 12 patients and failed in one.The highfrequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency applications.The vagal reaction was observed before the improvement of the sinus and AV node function.No complications occurred during the procedures.Patients were followed up for a mean of 13.0±5.9 months.During the follow up ten patients remained free of symptoms,and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of syncope.The heart rate of post-ablation was higher than pre-ablation(69.0±11.0 vs.49.0±10.0 beats/min,t=4.56,P=0.008).The sinus node recovery time,Wenckebach block point,and atrium-His bundle interval were significantly shorter after ablation(1386.0±165.0 vs.921.0±64.0 ms,t=7.45,P=0.002;590.0±96.0 vs.464.0±39.0 ms,t=2.38,P=0.023;106.0±5.0 vs.90.0±12.0 ms,t=9.80,P=0.013 before and after ablation procedure,respectively).Conclusions:Ablation of sinoatrial and AV nodal peripheral fibrillar myocardium electrical activity might provide a new treatment to ameliorate paroxysmal sinus node dysfunction,high degree AV block,and vagal-mediated syncope.