Evaluation of early results of patients with permanent peacemakers implantation at Bai Chay Hospital from 2016 to 2020

Objectives: Review the results of pacing and some early complications of patients Who implanted pacemaker at Bai Chay Hospital from 2016 to 2020. Subjects and research methods: A descriptively prospective study longitudinal follow-up study on 31 bradyarrhythmia patients who were permanently paced at Bai Chay Hospital from 2016 to October 2020. Results: After implantation of pacemaker, the rate of symptoms improved markedly, the change was statistically significant with p = 0.0001. Medium heart rate before and after implantation (47.84 ± 7.712 with 65.61 ± 4.425, 95%CI: 17.77 ± 7.173, p = 0.000). Change in QRS width after implantation (153.52 ± 11,963ms vs 91.81 ± 10,882ms, 95%CI 61.71 ± 12,947, p = 0.000). Pacing threshold changed after 6 months (0.68 ± 0.146V; 0.73 ± 0.149; p=0.001). Received R wave and electrode wire impedance did not changing after 6 months of follow-up. The rate of complications right after the procedure accounted for a total of 6.45%. The rate of complications after 6 months of follow-up accounted for 6.45%. Complications were all minor complications and were well managed. The successful rate of the procedure reached 100%, the pacing parameter was assessed as good, accounting for 70.97%. Conclusion: The method is considered effectively in the symptom improvement, safety, low complication rate and should be applied and deployed for patients with bradyarrhythmias with indications for permanent pacemaker implantation.

Relationship of NT-ProBNP and pacemaker parameters in patients with sick sinus syndrome?

Objectives: NT-ProBNP could influence the pacemaker parameters in patients with sick sisnus syndrome? Methods and Results: 93 patients with sick sinus syndrome were implanted 2 chambers pacemaker with mean aged 61,19±14,95 years old and 37,6% of male. The pacemaker parameters of ventricular lead include: Pacing thresholds were measured 0.75 ± 0.17 V, sensing amplitudes were measured 9,93 ± 4.01 mV, and lead impedances were measured 710,06 ± 130,86 ᾨ. The pacemaker parameters of atrial lead include: Pacing thresholds were measured 1,06 ± 0,29 V, sensing amplitudes were measured 2,58 ± 1,23 mV, and lead impedances were measured 509,13 ± 69,22 ᾨ. There is not significantly relationships of NT-ProBNP and pacemaker parameters of ventricular lead, atrial lead impedance, atrial lead sensing amplitudes (p>0,05). However, there is significantly relationship of NT-ProBNP and atrial lead pacing threshold (r=0,34; p=0,003). Conclusion: There is significantly relationship of NT proBNP and atrial lead pacing threshold in patients with sick sinus syndrome who were implanted the pacemaker.

536 Intraoperative predictors of long-term pacing threshold improvement in leadless pacemakers

Aims Micra-VR transcatheter pacing system (TPS) has shown strong stability of electrical parameters over time. Nevertheless, a small percentage of patients develops high pacing threshold (PT) (>1 [email protected] ms) which can decrease the longevity of battery. Our study sought to investigate the intraoperative electrical parameters able to predict device electrical performances during the time. Methods and results Patients (pts) implanted with Micra-VR TPS from March 2018 to January 2021 were prospectively considered at the Cardiology Department of Spedali Civili Hospital (Brescia) and Luigi Sacco Hospital (Milan). R-wave sensing amplitude (mV), pacing impedance (Ohm), and PT ([email protected] ms) were recorded twice: upon Micra final positioning, and after removal of the delivery system. All pts received a follow-up visit at 1- and 12-month after discharge. Electrical parameters were recorded at each visit. A total of 93 pts underwent Micra-VR implantation were enrolled. When compared to the first assessment, R-wave amplitude increased of 19.1% at second control performed after 13 ± 4 min (+1.71 ± 0.2 mV, 95% CI: 1.4–2.02; P < 0.001). Conversely, PT significantly decreased of 22.1% at 12-month follow-up respect to baseline (−0.22 ± 0.03 V, 95% CI: −0.13 to − 0.31; P < 0.001) (Figure 1). Among patients with high PT, acute increase of R-wave sensing of 1.5 mV after 14 ± 4 min significantly predicted PT normalization (≤1 [email protected] ms) 12 months post-implant (R = 0.72, 95% CI: 0.13–0.33, P < 0.001) (Figure 2), with a sensitivity of 87.5% (95% CI: 0.61–0.98) and a specificity of 88.8% (95% CI: 0.51–0.99) (Figure 3). Conclusions A 1.5 mV increase in R-wave amplitude at implant time is predictive of PT normalization (<1.0 V/0.24 ms) at 12-month FU. This finding may have practical implications for device repositioning in case of HPT at implant. This parameter could be considered for acute device repositioning, particularly in HPT patients. 536 Figure

283 His bundle pacing: safety, performance, and clinical outcomes in a single-centre experience

Aims Permanent His bundle pacing (HBP) is a more physiological technique for cardiac stimulation and has recently emerged as an alternative for anti-bradycardia pacing and cardiac resynchronization therapy (CRT). Its main advantages over ‘classical’ pacing are both its protective role over pacing-induced cardiomyopathy and the possibility of resynchronization by normalization of His-Purkinje activation. To evaluate the intermediate-term outcomes of HBP in terms of safety, performance, and clinical outcomes. Methods and results Between December 2018 and July 2020, we enrolled a series of consecutive patients with indication for pacing in whom HBP was attempted. A specific lead (3830 Select Secure MRI SureScan) and sheath (C315His) was used. At follow-up clinical, safety and performance outcomes were evaluated. A significant rise in HBP pacing threshold was defined as an increase of at least 1 V@1ms in the minimum voltage that could produce an effective myocardial depolarization. Remote or in-hospital device interrogation was performed by an experienced electrophysiologist. HBP was attempted in 99 patients and all implantations were performed by the same two operators. Eighty-two procedures were successful (83%). The main reasons for HBP failure were high pacing-thresholds (n = 8, 47%), infra-Hisian block (n = 5, 29,4%), difficult HB location (n = 3, 17,6%), unsatisfactory sensing (n = 1, 5,9%), or lead instability (n = 1, 5,9%). During a mean follow-up of 9.5 ± 5.9 months, the overall technical and clinical complication rates were 39% and 13.3%, respectively. Three (3.6%) patients underwent His lead extraction and subsequent conventional right ventricular septum (RV) lead implantation because of lead dislodgement (n = 2) or rise in pacing threshold (n = 1), while two (2.4%) patients required His lead repositioning because of lead dislodgement (n = 1) and phrenic nerve stimulation (n = 1). Nineteen patients (23.2%) experienced a significant rise in Hisian pacing threshold and 1 of these patients also had poor sensing parameters. Oversensing was noted in 8 (9.7%) patients and in 7 of them (87.5%) it was due to both atrioventricular and ventriculoatrial crosstalk events. As regards clinical outcomes, seven patients (8.5%) were diagnosed with new onset atrial fibrillation (AF), one of them complicated by stroke. Three patients (3.6%) were hospitalized for acute heart failure, one of them after His lead dislodgement. Finally, five patients (6.1%) died during follow-up, but no death was related to cardiovascular events. Conclusions HBP is an effective technique to obtain a more physiological cardiac pacing, but it is limited by a moderate rate of procedural failure and follow-up complications, mainly rising in pacing threshold and oversensing events. This is probably due to suboptimal implantation tools and lack of specific programming algorithms. New dedicated tools, increased experience, knowledge of device limitations, and optimal programming are needed to improve future outcomes.

616 Endocardial lead placement guided by high resolution voltage mapping in a patient with recurrent failure of transvenous pacing system

Methods and results A 58 years-old man was admitted to our intensive care unit for syncope due to inconstant capture of epicardial ventricular lead. His cardiovascular history began 20 years before when he underwent single chamber pacemaker implantation with insertion of a passive fixation ventricular lead for symptomatic complete atrio ventricular block (AVB). Electrical parameters were good at implantation. However, during follow-up a gradual and progressive increase of pacing threshold occurred, with no changes in impedance values, finally leading to complete loss of ventricular capture. Hence, 2 years later, the lead was extracted and a new transvenous ventricular lead was placed in septal position. All electrical parameters were optimal at the end of the procedure. However, in the following months threshold values gradually increased as previously observed. The referring clinicians decided to surgically extract both the device and transvenous lead and to implant an epicardial ventricular lead connected to an abdominal generator. The pacemaker worked properly for about 17 years until he was transferred to our institution with evidence of inconstant lead capture at maximum pacing outputs. A temporary transvenous pacemaker was immediately inserted. Clinical examination, laboratory exams, and echocardiography were normal. Cardiac magnetic resonance (MRI) was not feasible due to the epicardial lead. Thus, in order to obtain cardiac substrate characterization, we decided to perform high density multielectrode voltage mapping of the right ventricular endocardium with HD Grid multielectrode mapping catheter (HD Grid mapping catheter sensor enabled, Abbott Technologies, Minneapolis, MN). Electroanatomic voltage map allows distinction of areas of healthy myocardium (>1.5 mV) from scar tissue (<0.5 mV). Unexpectedly, voltage mapping highlighted no scar zones, showing a globally normal endomyocardial surface. Therefore, a new endocavitary pacemaker was inserted in right prepectoral region and an active fixation right ventricular lead was placed on mid-ventricular septum. A backup pacing lead was placed in a more apical position in an area of endocardial healthy myocardium. Post-procedural sensing, impedance and capture threshold were optimal (0.3 V × 0.4 ms for mid-septal lead and 0.3 × 0.4 ms for the other one). At 1 month follow-up mid-septal lead’s threshold was slightly increased (1.0 V × 0.4 ms) and further increase was observed at 3-month outpatient visit (1.75 V × 0.4 ms). Capture threshold of the other lead and other parameters were stable. The patient received remote monitoring for home surveillance of the implanted system. Home monitoring shows a trend toward a progressive increase of pacing threshold of the mid-septal lead and stable value of the other electrode. Conclusions The present report suggests an innovative use of high-density mapping with HD Grid catheter to characterize endocardial right ventricular myocardium in a patient with contraindication to cardiac MRI and recurrent failure of previous implanted pacing systems for unknown reason and to guide effective lead placement in areas of normal endocardial voltage. Combined use of telemedicine and high-resolution mapping technique allowed us to avoid unnecessary high risk reintervention for novel epicardial lead placement.

204 Permanent his bundle pacing using stylet-driven lead in patients with right atriomegaly: a single-centre experience

Aims His bundle pacing (HBP) is becoming an increasing widespread approach for physiological pacing. However, successful HBP procedure could be hampered by limited implantation tools especially in challenging anatomies. We aimed to report our experience with HBP technique using a novel stylet-driven lead system in patients with right atriomegaly. Methods and results Consecutive patients with right atrium (RA) volume >25 ml/m2 in men and >21 ml/m2 in women who underwent permanent HBP for standard indications were enrolled from March 2020 to March 2021. The tool of first choice for HBP attempt was a stylet-driven lead (Solia S 60, Biotronik) delivered via a dedicated introducer sheath (Selectra 3D, Biotronik). The acute, 1-month and 6-month procedural success rates were assessed. We enrolled 24 patients [median age: 75 (70–79) years, 85% men] with an average RA volume of 50.7 ± 7.8 ml/m2. At implant, conduction system pacing using stylet-driven lead was achieved in 21 patients (87%): 12 (50%) selective HBP, 6 (25%) non-selective HBP, and 3 (12.5%) left bundle branch area pacing. In the three failures, HBP was further attempted with a lumen-less lead with fixed helix (SelectSecure 3830, Medtronic) with final procedural success in two cases. In the successful cases, there was a significant reduction of QRS duration between paced and spontaneous beats [152.5 (130–167.5) ms vs. 130 (122.5–137.5) ms, P = 0.003]. No lead dislodgment nor significant pacing threshold increase was observed at 1-month (1.30 ± 0.76 [email protected] vs. 1.32 ± 0.80 [email protected] ms, P > 0.9) and 6-month follow-up (1.30 ± 0.76 [email protected] vs. 1.38 ± 0.97 [email protected] ms, P = 0.66). Conclusions In patients with right atriomegaly, the novel stylet-driven lead system showed high implant success rates with stable pacing thresholds.

Preliminary study on left bundle branch area pacing in children：clinical observation of 12 cases

Objective: To explore the safety and feasibility of left bundle branch area pacing (LBBAP) in children. Methods: This study observed 12 children attempted LBBAP from 2019 to 2021 in our department prospectively. Clinical data, pacing parameters, electrocardiograms, echocardiographic measurements and complications were recorded at implant and during follow-up. Results: The 12 patients aged between 3 and 14ys and weighted from 13 to 48kg. 11 patients were diagnosed with third-degree AVB and 1 patient (case 4) suffered from cardiac dysfunction due to right ventricular apical pacing (RVAP). LBBAP was successfully achieved in all patients with narrow QRS complexes. LVEF of case 4 recovered on the 3rd day after LBBAP. The median of LVEDD Z score of the 12 patients decreased from 1.75 to1.05 3 months after implantation (p<0.05). The median of paced QRS duration was 103ms. The median of pacing threshold, R-wave amplitude and impedance were 0.85V, 15mV and 717Ω respectively and remained stable during follow-up. No complications such as loss of capture, lead dislodgement or septal perforation occurred. Conclusions: LBBAP can be performed safely in children with narrow QRS duration and stable pacing parameters. Cardiac dysfunction caused by long-term RVAP can be corrected by LBBAP quickly.

Management of pacemaker patients after myocardial infarction

Myocardial infarction (MI) is the leading cause of death and disability in the population. Effective restoration of coronary blood flow in the infarction-dependent artery during percutaneous coronary intervention contributes to the regression of structural and functional remodeling of the left ventricle. Meanwhile, in 18% of cases, patients with myocardial infarction require implantation of a pacemaker because of the cardiac conduction disorders, among which atrioventricular blockade is the leading one. The need for pacemaker implantation is determined by the clinical features and the type of bradycardia complicating myocardial infarction. The scope of preventive measures at the stage of outpatient specialized cardiac care for patients with myocardial infarction and pacemaker includes medical, physical, and psychological rehabilitation. In addition, the presence of an implantable pacemaker necessitates specialized dynamic monitoring by an arrhythmologist, including programming the pacemaker. Performing a magnetic test allows to assess the efficiency of the pacemaker, the level of its charge and promptly determine the need to its replacement. Determination of the pacing threshold ensures efficient operation of the implantable device. After discharge from the hospital, a schedule for checking the pacemaker is determined, namely, 3 months after the date of implantation of the pacemaker, then 1-2 times a year. In the event of complaints of dizziness, fainting or damage of the pacemaker implantation site, the pacemaker check is carried out unscheduled. Patients with a history of myocardial infarction and an implantable pacemaker should be informed about the limitations that may be associated with the presence of a pacemaker. It is recommended to exclude contact with possible sources of electrical interference as much as possible, to avoid medical physiotherapy using galvanic currents. When using industrial or household equipment, safety precautions must be followed.