Conventional Pacemaker Research Articles

Leadless or Conventional Transvenous Ventricular Permanent Pacemakers: A Nationwide Matched Control Study

BackgroundLeadless ventricular permanent pacemakers (leadless VVI or LPM) were designed to reduce lead‐related complications of conventional VVI pacemakers (CPM). The aim of our study was to assess and compare real‐life clinical outcomes within the first 30 days and during a midterm follow‐up with the 2 techniques.Methods and ResultsThis French longitudinal cohort study was based on the national hospitalization database. All adults (age ≥18 years) hospitalized in French hospitals from January 1, 2017 to September 1, 2020, who underwent a first LPM or CPM were included. The study included 40 828 patients with CPM and 1487 with LPM. After propensity score matching 1344 patients with CPM were matched 1:1 with patients treated with LPM. Patients with LPM had a lower rate of all‐cause and cardiovascular death within the 30 days after implantation. During subsequent follow‐up (mean: 8.6±10.5 months), risk of all‐cause death in the unmatched population was significantly higher in the LPM group than in the CPM group, whereas risk of cardiovascular death and of endocarditis was not significantly different. After matching on all baseline characteristics including comorbidities (mean follow‐up 6.2±8.7 months), all‐cause death, cardiovascular death, and infective endocarditis were not statistically different in the 2 groups.ConclusionsPatients treated with leadless VVI pacemakers had better clinical outcomes in the first month compared with the patients treated with conventional VVI pacing. During a midterm follow‐up, risk of all‐cause death, cardiovascular death, and endocarditis in patients treated with leadless VVI pacemaker was not statistically different after propensity score matching.

Abstract P2086: Wirelessly Powered Miniaturized Intravascular Pacemaker Based On Inductive Coupling

Introduction: Despite unparalleled advantages, clinical lead-associated complications of the conventional pacemakers remain to compromise patient safety and survival, accounting for nearly 10% of all implants. The leadless pacemakers from Medtronic or St. Jude Medical are revolutionary products, however, the integrated battery introduced new clinical constraints and health risks. Therefore, developing leadless pacemakers incorporating wireless powering owns special clinical significance to further the miniaturized integration and reduce the repetitive mechanical workload for the hearts. Methods and Results: Hereby, we achieved the leadless intravascular miniaturized pacemaker powered by electromagnetic inductive coupling. The miniaturized assembling was built up from flexible circuit boards, integrating with receiver coils and tiny electrical components for the RF-DC converting. The substrate circuit board will be bent into a cylinder with a diameter of 2.7 mm and filled with PDMS to achieve the electrical isolation and form a narrower tip for easy insertions (Figure 1a,b). The voltage of DC pulse converted at the wireless pacemaker depends on the DC voltage for the RF amplifier and the gap between the coils, ranging from 0.5V to 5V or higher (Figure 1c). After inserting the pacemaker into the anterior vein, the pacing demonstration showed the stimulation spikes and the following regular cardiac Q-R-S-T waves, indicating the pacemaker can stimulate the intrinsic cardiac rhythms (Figure 1d,e). Conclusions: The proposed medical device reveals the potentials of cardiac pacing from the anterior veins and paved the way to further device miniaturization for the intravascular deployment.

Clinical outcome for heart failure hospitalizations in patients with leadless pacemaker.

IntroductionThe long‐term performance of leadless pacemaker (LPM) has not been well evaluated.MethodsBetween September 2017 and January 2021, 929 consecutive patients who underwent pacemaker implantation were grouped according to the types of pacemakers: LPM (LPM group, n = 368) and conventional pacemaker (PM group, n = 561).ResultsThe median follow‐up duration was 1.7 years (interquartile range 0.8–2.6 years). Hospitalization rate for heart failure in the LPM group was 9.3%, 15.6%, and 21.6% at 1, 2, 3 years, respectively. The LPM group had a significantly higher adjusted heart failure hospitalization risk than the PM group [hazard ratio (HR) 1.70, 95% confidence interval (CI) 1.09–2.64, p = .01]. More patients with symptomatic bradycardia caused by sinus node dysfunction (SND) in the LPM group (n = 150) were admitted to the hospital for heart failure compared to those in the PM group (n = 219) (HR 2.02, 95%CI 1.04–3.90, p = .03), whereas no significant difference was observed between the two groups in the patients with bradycardia caused by atrial fibrillation (LPM group, n = 71; PM group, n = 18) or atrioventricular block (LPM group, n = 147; PM group, n = 324).ConclusionsPatients who received LPM implantation had greater hospitalization risk for heart failure, compared to those who received conventional pacemaker implantation. The increased risk was mainly attributed to patients with SND.

Baseline clinical characteristics of heart failure patients with reduced ejection fraction enrolled in the BUDAPEST-CRT Upgrade trial.

The BUDAPEST-CRT Upgrade study is the first prospective, randomized, multicentre clinical trial investigating the outcomes after cardiac resynchronization therapy (CRT) upgrade in heart failure (HF) patients with intermittent or permanent right ventricular (RV) pacing with wide paced QRS. This report describes the baseline clinical characteristics of the enrolled patients and compares them to cohorts from previous milestone CRT studies. This international multicentre randomized controlled trial investigates 360 patients having a pacemaker (PM) or implantable cardioverter defibrillator (ICD) device for at least 6 months prior to enrolment, reduced left ventricular ejection fraction (LVEF ≤35%), HF symptoms (New York Heart Association [NYHA] functional class II-IVa), wide paced QRS (>150 ms), and ≥20% of RV pacing burden without having a native left bundle branch block. At enrolment, the mean age of the patients was 73 ± 8 years; 89% were male, 97% were in NYHA class II/III functional class, and 56% had atrial fibrillation. Enrolled patients predominantly had conventional PM devices, with a mean RV pacing burden of 86%. Thus, this is a patient cohort with advanced HF, low baseline LVEF (25 ± 7%), high N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels (2231 pg/ml [25th-75th percentile 1254-4309 pg/ml]), and frequent HF hospitalizations during the preceding 12 months (50%). When compared with prior CRT trial cohorts, the BUDAPEST-CRT Upgrade study includes older patients with a strong male predominance and a high burden of atrial fibrillation and other comorbidities. Moreover, this cohort represents an advanced HF population with low LVEF, high NT-proBNP, and frequent previous HF events. ClinicalTrials.gov NCT02270840.

Wireless Communication Between Paired Leadless Pacemakers for Dual-Chamber Synchrony.

Leadless pacemakers (LPs) can mitigate conventional pacemaker complications related to the transvenous leads and subcutaneous pocket surrounding the pulse generator. Although single-chamber leadless pacing has been established, multichamber pacing requires wireless bidirectional communication across multiple LPs to maintain synchrony. This preclinical study demonstrates the chronic performance of implant-to-implant (i2i) communication that achieves synchronous, dual-chamber pacing with 2 LPs. The i2i communication modality employs subthreshold electrical signals conducted between implanted LPs through the blood and myocardial tissue on a beat-by-beat basis. Right atrial and right ventricular LPs were implanted in 9 ovine subjects. The i2i transmission performance was evaluated 13 weeks after implant. Right atrial and right ventricular LPs were implanted successfully and without complication in 9 ovine subjects. A total of 8715±457 right atrial-to-right ventricular and right ventricular-to-right atrial transmissions were sent per hour, with a success rate of 99.2±0.9%. Of periods with i2i communication failure when DDD pacing was not possible, 97.3±1.8% were resolved within 6 s. For the first time, synchronized, dual-chamber pacing has been demonstrated in a chronic preclinical feasibility study by 2 leadless pacemakers using beat-to-beat, wireless communication, achieving a success rate of 99.2%.

VDD leadless pacemaker: atrioventricular synchrony predictors

Abstract Funding Acknowledgements Type of funding sources: None. Background Leadless pacemaker technology has shown a reduction of the complications associated with conventional pacemakers. The development of the VDD mode has allowed us to extend the use of leadless pacemakers to patients in need of pacing due to atrioventricular (AV) block. Maintaining AV synchrony (AVS) in cardiac pacing improves cardiac output and quality of life and reduces the risk of atrial fibrillation (AF) and pacemaker syndrome. In previous analyses, it was observed that the low amplitude of the A4 signal was associated with low AVS. Methods Prospective single-center study of consecutive patients who received a VDD leadless pacemaker (Micra AV), and who remained in VDD mode throughout the follow-up. Our purpose was to analyze the possible predictors of A4 signal amplitude and AVS in the first month of follow-up. We tested univariate association with A4 signal and AVS of echocardiographic data, clinical variables, implant parameters, and pacemaker function. Results We included data from the first 21 patients who received a VDD leadless pacemaker (Micra AV) between Jun/20 and Apr/21. 18 patients remained in VDD mode after the first month of follow-up. There was no significant association between ventricular filling waves (E and A) and Tissue-Doppler diastolic waves (E ’and A’) with the A4 signal and the percentage of AVS. Only the E / A ratio showed a trend of association with the percentage of AVS, although it did not reach statistical significance (p = 0.09), showing an inverse relationship (Pearson’s correlation coefficient of -0.396). None of the clinical variables analyzed showed an association with the A4 signal or with the percentage of AVS. Only the A4 signal was significantly associated with the percentage of AVS (Pearson´s correlation coefficient of 0.524, p = 0.02). Considering 85% as an adequate discriminator for correct AVS, the mean signal of A4 was significantly lower (p = 0.03) in those with AVS < 85% (2.63 ± 1.73) compared with those with AVS≥85% (4.37± 1.34). Regarding implant factors, there seems to be a tendency to worse AVS with higher number of releases (p = 0.06, Pearson’s correlation coefficient of -0.460), as well as when implanting in positions further away from the atrium (medium interventrcular septum vs. high interventricular septum / proximal right ventricular outflow tract; p = 0.06, Pearson’s correlation coefficient of -0.463). Conclusions Although this is a short case series, our results are aligned with the data from the MARVEL2 AVS predictors substudy. It appears that the main predictor of higher AVS is the A4 signal. Device position, as well as the number of releases, could also play a role. Nevertheless, it is necessary to continue the analysis with the data of future patients to corroborate these preliminary findings.

Pacemaker upgrade to Cardiac Resynchronization Therapy-defibrillator or Cardiac Resynchronization Therapy-pacemaker without prior ventricular arrhythmias

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by the ÚNKP-21-3-II-SE-47, ÚNKP-20-3-I-SE-43 New National Excellence Program if the Ministry for Innovation and Technology in Hungary. Project no. NVKP_16-1–2016-0017 (’National Heart Program’) has been implemented with the support provided by the National Research, Development and Innovation Fund of Hungary, funded under the NVKP_16 funding scheme. The research was financed by the Thematic Excellence Programme (2020-4.1.1.-TKP2020) of the Ministry for Innovation and Technology in Hungary, within the framework of the Therapeutic Development and Bioimaging thematic programmes of the Semmelweis University. This work was also supported by the Semmelweis 250+ Excellence PhD Scholarship (EFOP-3.6.3-VEKOP-16-2017-00009). Background Cardiac Resynchronization Therapy (CRT) can reverse the harmful effects of right ventricular pacing (RVP). Data are scarce on comparing long-term survival among patients who undergone CRT-defibrillator (CRT-D) or CRT-pacemaker (CRT-P) upgrade from pacemakers (PM) without prior ventricular arrhythmias (VAs). Purpose We compared the differences in long-term all-cause mortality among PM patients receiving CRT-D or CRT-P upgrade. Methods Patients with conventional PMs developing heart failure despite optimal medical treatment and a high rate of RVP with no prior VAs were included. Altogether 326 patients were investigated, 117 (36%) upgraded to CRT-D, 209 (64%) to CRT-P in our retrospective registry. The primary endpoint was all-cause mortality. Subgroup analyses were performed by comorbidities and CRT device types. Using topological data analysis, we identified risk groups based on the primary endpoint. Results During the median follow-up time of 3.6 years, 33 (28%) CRT-D and 145 (69%) of CRT-P upgrade patients reached the primary endpoint. The CRT-D upgrade group showed a lower risk of all-cause mortality in the total cohort (HR: 0.55; 95% CI: 0.38-0.81; p=0.002) and by ischaemic aetiology (HR: 0.47; 95% CI: 0.29-0.76; p=0.002) compared to CRT-P. After adjustment, CRT-D, male gender and loop diuretics proved as independent predictors of all-cause mortality. Patients upgraded with CRT-D demonstrated favourable survival in the high-risk group over CRT-P. Conclusions Patients had survival benefit after CRT-D upgrade, compared to CRT-P, in the high-risk group and with ischaemic heart failre aetiology. However, no difference could be observed between the two groups among low- and intermediate-risk patients.

Leadless pacemaker implantation after transcatheter aortic valve replacement

Abstract Funding Acknowledgements Type of funding sources: None. Background Impairment of the conduction system may occur in 9-30 % of patients undergoing transcatheter aortic valve replacement (TAVR). Since this is typically an elderly and frail patient population, leadless pacing potentially offers benefits over conventional transvenous pacemaker devices. However, available efficacy and safety outcome data of leadless pacing in a population who underwent a TAVR procedure is still limited. Purpose Retrospective analysis of efficacy and safety outcome data in patients who underwent leadless pacemaker implantation after TAVR due to relevant bradycardias. Methods and Results In this retrospective analysis from two large Swiss implantation centres, 257 consecutive patients undergoing leadless pacemaker were included. Of the total cohort, 26 subjects had a previous TAVR complicated by early (within 30 days)- or late-onset (after 30 days) bradycardias (Table 1). The TAVR group did not differ compared to the non-TAVR with regard to age, gender and left-ventricular ejection fraction (LVEF). Median duration between valve intervention and leadless pacemaker implantation was 8 days (range 0 to 368 days). After a TAVR procedure, left femoral access was chosen in 30.8% (8 of 26 of cases) for the leadless pacemaker implantation as compared to 5.2% (12 of 231 of the cases) in the remaining population (P < 0.01). Mean implantation duration was 56 ± 22 min in the TAVR group compared to 48 ± 20 min (P = NS) and a successful implantation rate of 100.0 % in the TAVR group vs 98.7% in the remaining population (P = NS). There were no significant differences in pacing parameters (sensing, impedance and threshold, respectively) between the two groups. A total of eight major periprocedural complications (3.1%) were encountered in the entire cohort within 30 days, of which one (pericardial effusion) occurred in the TAVR population (P = 0.04), which was managed conservatively with pericardiocentesis. Conclusions Leadless pacemaker implantation appears to be safe and effective in patients after TAVR in need of antibradycardia pacing.

Leadless pacemaker implantation in patients with a previous transvenous device

Abstract Funding Acknowledgements Type of funding sources: None. Background Leadless pacing has been established as an alternative approach to transvenous devices for selected patients suffering from bradycardias. While in the majority of cases leadless pacemaker implantation represents a de novo procedure, in an increasing number of patients such a device is used after a previously implanted transvenous pacemaker. Purpose Retrospective analysis of the efficacy and safety outcome in patients who underwent leadless pacemaker implantation in the context of a previously implanted conventional pacemaker. Methods and Results In this retrospective analysis from two large Swiss implantation centres, 257 consecutive patients undergoing leadless pacemaker implantation were included. Of the total cohort, 233 patients were diagnosed with new-onset bradycardias, while in 24 patients a prior transvenous device was present. Out of these 24 patients, 20 subjects required lead extraction of the previous system due to infection (70%, 14 patients), malfunction or other reasons (Table 1). In 3 patients with device-related infection, lead extraction and leadless pacemaker implantation were performed as a single procedure, while in the remaining 11 cases a time window between the two procedures was present (median of 11.5 days with a range of 2 to 186 days). In the population with a previous device, mean age at implantation was 81 ± 9 years which did not differ compared to the de novo cohort. Mean implantation duration was 57 ± 31 minutes in the cohort with a previous device versus 48 ± 191 minutes in the de novo population without a significant difference (P=NS) and with a successful implantation rate of 100% versus 98.7% in the de novo population (P=NS). Electrical device parameters (sensing, impedance, threshold) at implantation and during follow-up (mean 12.5 ± 9.3 months) were similar between the two groups. Eight major periprocedural complications (3.1%) were encountered (4 pericardial effusions, 3 femoral bleedings and 1 intra-abdominal bleeding) in the entire cohort within a 30 days period, of which the majority occurred in the de novo cohort (75 %, 6 of 8). A total of 4 pericardial effusions occurred, which could be managed without the need for cardiac surgery. The were no reinfections registered after leadless pacemaker implantation during follow-up. Conclusions Implantation of a leadless pacemaker in patients with a prior conventional system (with or without extraction of the previous device) was effective and safe in our population of patients.

Conductive Backscatter Communication for Dual-Chamber Leadless Pacemakers

Dual-chamber and multichamber leadless pacemakers (PMs) are emerging solutions for reducing the limitations of conventional wire-based PMs. One of the main challenges in migrating to leadless PMs is having reliable and low-power data telemetry among the PMs inside the heart chambers. Backscatter communication is a solution for battery-constrained data links and can be applied for the implants using specific designs. In this article, we propose one-way backscatter communication based on conductive coupling for leadless PMs. The implant capsules can communicate with an on-body device without having any active transmitter. The complexity and power consumption are shifted to the remote on-body reader. Dual-chamber PM communication is enabled by using the subcarrier technique for discriminating the devices in the frequency domain. A low data rate of about 11 kb/s is assigned to each PM capsule to communicate its vital information to the reader. The proposed system is designed and realized using off-the-shelf electronic components. The whole system is evaluated in an <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in vivo</i> experiment. Results indicate the potential of using conductive backscatter for wireless communication in leadless PMs.

HOLTER ECG MONITORING AS METHOD FOR ASSESSING INTERACTION OF IMPLANTED PACEMAKER AND SOURCE OF ELECTROMAGNETIC INTERFERENCE

The aim of the study was to assess the interaction of the cardiostimulation system of the patient and the source of electromagnetic interference (EMI) during the patient’s work by Holter monitoring of ECG. Finally, to analyze ECG recording and evaluate possible pacemaker (PCM) program responses to the presence of EMI. The observation was performed in the selected patient with the single-chamber conventional pacemaker during practicing of a profession in an industrial environment with a real risk of interaction with the defined source of interference. The heart rhythm was monitored with a standard Holter monitor and the measurement was repeated during three work shifts. The PCM was revised before each measurement and at the same time the programming was adjusted for monitoring purposes. The ECG record was back-analyzed and the device response to the presence of EMI was evaluated. No program response to the presence of an interfering electromagnetic field (EMF) was observed from the ECG recording analysis. This program response would manifest to abnormalities in the ECG curve (asynchronous pacing, pacing inhibition, competitive pacing). There were no events in the PCM memory indicating the effect of the EMI.

Leadless Pacemaker Implantation in a Patient With Diminutive Subclavian Veins.

Conventional pacemakers have a longstanding history of preventing morbidity and mortality in patients with bradyarrhythmia and conduction disorders. While decades of advancements have improved pacemaker technology and implantation technique, insertion of transvenous leads and formation of a pectoral pocket can lead to complications, including pocket hematoma, pneumothorax, or infection. Leadless pacemakers were introduced in 2012 to address these complications; however, early leadless systems only provided single-chamber ventricular pacing. In 2020, an accelerometer-based atrial sensing feature was developed to allow for atrioventricular (AV) synchrony with these devices. Early evidence suggests that patients with sinus rhythm and AV block can benefit from single-chamber leadless pacing systems with an AV synchrony algorithm. As availability of these devices continues to broaden, identification of appropriate recipients has become increasingly relevant.

JCS/JHRS 2021 guideline focused update on non-pharmacotherapy of cardiac arrhythmias.

JCS/JHRS 2021 guideline focused update on non-pharmacotherapy of cardiac arrhythmias.

Atrioventricular Block in a Patient with Persistent Left Superior Vena Cava and Absent Right Subclavian Vein: A Case Report

Persistent Left Superior Vena Cava (PLSVC) is an uncommon congenital anomaly, with an incidence of 0.5% in the general population. Moreover, the right superior vena cava anomaly with PLSVC is even rarer, with an incidence of 0.09%-0.13% in the general population. Patients with PLSVC and an absent right subclavian vein may present complications when undergoing conventional pacemaker lead implantation due to their vein anomalies. In this case report, a leadless pacemaker proved to be a useful alternative in a patient with the complete atrioventricular block with PLSVC and an absent right subclavian vein defect, the latter being found incidentally during the initial pacemaker implantation. This case highlights the importance of evaluating the presence of vascular malformations before surgical intervention.

Abstract 9607: CIED and Non-CIED MRI Imaging; Should Capped or Uncapped Abandoned Leads Remain a Contraindication?

Introduction: Infrequently, MRI is performed on patients with conventional pacemakers or ICDs. While multiple studies have documented the safety of MRI scans when performed with an approved protocol, retained leads (capped or uncapped) remain a significant concern. Hypothesis: We hypothesize that non-CIED and CIED devices in the presence of capped and uncapped leads, while inherently having no ability to for interrogation, can be performed under a similar MRI-device protocol in a safe and reliable fashion. Methods: Adapting the same MRI-device protocol as for either CIED or non-CIEDs as appropriate, tracking of patient safety to include chest pain, sustained arrhythmias or change in any device setting was performed. Results: A total of 311 pts with CIED (81%) and non-CIED (19%) from 2019-2021 at Allegheny General Hospital incorporating a total of 16 (5%) pts with retained/abandoned/fragmented leads (56% capped and 44% uncapped; p=NS) as well as 3 epicardial leads underwent MRI (GE; EXCITE, 1.5T; WI) of several regions (Brain; 72%, Ortho; 17% and CV; 11%). Repeat imaging was common (12%). Utilizing an established device protocol according to CIED or non-CIED, pts were programmed based on pt-specific pacing requirements. There were no episodes of abnormal vital signs, chest pain, sustained arrhythmias or any clinically significant device setting changes. No significant changes to impedance, amplitude, voltage or sensitivity to RA or RV/LV parameters occurred. There were no differences, naturally, between capped, uncapped or epicardial lead metrics. Likewise, no power-on resets or pacing changes were noted in the primary device system. Altogether, this supports the absence of myocardial or extra-cardiac thermal-induced injury. Infrequent, clinically insignificantly decreased RA sensing, a common natural observation in contemporary interrogation, was infrequently and transiently noted. Conclusions: Following a standard MRI protocol, according to CIED and non-CIED in pts with either capped or uncapped abandoned leads, pts suffered no ill consequences when tracked for CP, arrhythmias or device setting changes supporting a proof-of-concept notion for removing yet another obstacle for often life-changing MRI in patients with PM/ICDs.

Abstract 12870: Transesophageal Echocardiography to Guide Correct Implantation Site of the Leadless Pacemaker

Introduction: MICRA™ (Medtronic USA) leadless pacemakers are used to avoid complications common to conventional pacemakers, but there is still a 4% risk of complications (e.g., cardiac perforation, tamponade, and embolization). Septal device implantation may decrease risk, but helpful cardiac landmarks (e.g., tricuspid valve, pulmonary valve (PV)) are not seen under fluoroscopy. There is little guidance regarding alternative intra-procedural (IP) imaging. We studied the spatial relationship of the MICRA™ to cardiac landmarks via transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE). Methods: Our prospective observational study included 23 patients undergoing MICRA™ implantation with TEE ( Table 1) . Interventricular septal placement was confirmed by fluoroscopy, electrocardiography (ECG) and TEE. Distances between the device and cardiac landmarks were measured by TTE and TEE and analyzed with ECG parameters during pacing ( Fig 1A, Fig 1B ). Results: Septal positioning of the device was achieved in all patients. TEE transgastric (0-20/90-110°) and lower mid-esophageal (40-60/130-150° with biplane) views best visualized device position. The aortic valve (AV) in the TTE apical 5 chamber view was used as a surrogate for RV apex to PV distance. With appropriate septal deployment, QRS morphology showed earlier R wave transition and 44% increased QRS width ( Table 1 ). Conclusions: TEE can guide appropriate leadless pacemaker septal implantation, and correlates with QRS pacing morphology. Further studies are required to establish reference ranges of distances from the device to cardiac landmarks to prove optimal device deployment.

Spanish Pacemaker Registry. 18th Official Report of the Cardiac Pacing Section of the Spanish Society of Cardiology (2020)

Introduction and objectivesThis report describes the cardiac pacing activity performed in Spain in 2020, including the number and type of implanted devices, demographic and clinical factors, and data on remote monitoring. MethodsInformation consisted of the European Pacemaker Patient Card, data submitted to the cardiodispositivos.es online platform, the databases of participating centers, and supplier-reported data. ResultsA total of 14 662 procedures were registered from 102 hospitals, representing 39.2% of the estimated activity. The implantation rates of conventional and low-energy resynchronization pacemakers were 759 and 31 units per million population, respectively. In all, 520 leadless pacemakers were implanted, 70 with atrioventricular synchrony. The mean age at implantation was high (78.8 years), and the most frequent electrocardiographic change was atrioventricular block. There was a predominance of dual-chamber pacing mode but VVI/R single-chamber pacing was used in 19% of patients in sinus rhythm, depending on age and sex. Remote monitoring capability was present in 18.5% of implanted conventional pacemakers and 45.6% of low-energy resynchronization pacemakers, although registration in this system increased by 53% in 2020. ConclusionsIn 2020, in the context of the SARS-CoV-2 pandemic, the number of implanted conventional pacemakers decreased by 8% and cardiac resynchronization therapy by 4.6%. The number of leadless pacemakers increased by 16.5%. Sequential pacing was predominant, influenced by age and sex. Home monitoring played a fundamental role as a mode of follow-up in this SARS-CoV-2 pandemic year.

Conventional transvenous or leadless ventricular permanent pacemakers: post-operative complications and mid-term follow-up

Abstract Introduction/Background Leadless ventricular permanent pacemakers (leadless VVI, LPM) were designed to reduce lead-related complications of conventional VVI pacemakers (CPM). Purpose The aim of our study was to assess and compare real-life clinical outcomes within the first 30 days and during a mid-term follow-up with the two techniques at a nationwide level. Methods This French longitudinal cohort study was based on the national hospitalization database covering hospital care from for the entire population. All adults (age ≥18 years) hospitalized in French hospitals From January 1, 2017 to September 1, 2020, who underwent a first LPM or CPM implantation were included. Importantly, patients with dual chamber pacemaker were not included in our study. Results Of 42,315 patients included in the cohort, 40,828 patients (96%) had a CPM and 1,487 had a LPM. Using propensity score, 1,344 patients with CPM were adequately matched in a 1:1 fashion with LPM patients. Clinical outcomes at day 30 In the unmatched population, within the 30 days after implantation, patients with LPM had a lower rate of all-cause mortality (OR: 0.635, 95% CI: 0.527–0.765, p&amp;lt;0.0001) and from a cardiovascular cause (OR: 0.568, 95% CI: 0.405–0.797, p=0.001). They also had lower rates of major bleeding and need for transfusion. There was no significant difference between groups regarding tamponade, pneumothorax or hemothorax. In the matched population, LPM implantation was still significantly associated with a lower rate of all-cause death (OR: 0.583, 95% CI: 0.456–0.744, p&amp;lt;0.0001), cardiovascular death (OR: 0.413, 95% CI: 0.271–0.629, p&amp;lt;0.0001), major bleeding (OR: 0.523, 95% CI: 0.348–0.786, p=0.002) or transfusion (OR: 0.481, 95% CI: 0.296–0.780, p&amp;lt;0.0001). However, tamponade, pneumothorax or hemothorax were not significantly different between the two groups. Clinical outcomes during mid-term follow-up In the unmatched patients, mean follow-up was 8.6±10.5 months. Annual incidence of all-cause death was high in both groups, and significantly higher in the LPM group than in CPM group (31%/year vs. 20%/year, p&amp;lt;0.0001) with a HR of 1.519 (95% CI: 1.296–1.780). Cardiovascular death was not significantly different between groups. Infective endocarditis was higher in the LPM group than in the CPM group with a HR of 2.108 (95% CI: 1.119–3.973). In the matched patients, mean follow-up was 6.2±8.7 months. All-cause death, cardiovascular death and infective endocarditis were not significantly different between groups. Conclusion Mortality is high among unselected patients implanted with ventricular permanent pacemakers, whether leadless or conventional pacemaker are used. Implantation of leadless pacemakers seems to be a safe procedure in this high-risk population, with better outcomes at 1 month. Mid-term outcomes appear relatively similar in LPM and CPM patients. Funding Acknowledgement Type of funding sources: None. Central illustration

Leadless pacemaker implant with concomitant atrioventricular node ablation: experience in a single center study with longterm followup

Abstract Introduction Feasibility of concomitant leadless-pacemaker (LP) implantation plus atrioventricular node ablation (AVNA) is unknown. Moreover, safety issues in the long run are also undetermined. It seems theoretically attractive since it could avoid one additional procedure and catheter could be introduced through the same sheath employed for the LP. On the contrary, risk of dislocation/electrical variations could represent a shortcoming. Objective We aim to report 1) feasibility of concomitant AVNA after a LP implantation and 2) long-term outcomes. Methods Single center, prospective and observational study of 256 consecutive patients with an indication for single-chamber pacemaker placement. The implantation procedure was carried out using a femoral approach and conventional technique. Successful implantation was accomplished in 255/256 patients referred for leadless implantation. In one patient, a complete obstruction of the inferior vena cava was documented, and a conventional unicameral pacemaker was implanted. Results 33 out of 255 patients underwent immediate AV ablation. Mean age was 75.2±8.3 years. Were predominantly females: 25 (75.7%) and indication was fast conduction atrial fibrillation (n=25), atypical flutter or atrial tachycardia (n=8). Mean acute “R wave” was 11.3mV, threshold of 0.55Vx0.24ms and impedance of 833Ω. Uneventful AV node ablation was performed in all of them immediately after LP implantation. Additional mean fluoroscopic time was 3.0 minutes. There were no vascular or arrhythmic complications after the implantation. After a mean follow-up of 27.9±12 months, all patients remained alive without notable event, and electrical parameters remained unchanged (Figure 1). Actuarial survival was shown in Figure 2. Conclusions Conconmitant AVN ablation after LP implantation seems feasible without remarkable complications in the long run. In our experience, this approach appears more comfortable for the patients and less time-consuming than conventional pacemaker implantation with sequential AV node ablation. There were no device macrodislodgements or unexpected device malfunctions in the follow-up period. Funding Acknowledgement Type of funding sources: None. Electrical performanceSurvival

Pacemaker upgrade to CRT-D or CRT-P without prior ventricular arrhythmias: a long-term single-centre retrospective analysis

Abstract Background Cardiac Resynchronization Therapy (CRT) can reverse the harmful effects of right ventricular pacing (RVP). Data are sparse on comparing all-cause mortality among patients undergone CRT-defibrillator (CRT-D) or CRT-pacemaker (CRT-P) upgrade from pacemakers without prior ventricular arrhythmias (VAs). Purpose We compared the differences in long-term all-cause mortality, postprocedural complications and the occurrence of VAs among patients receiving CRT-D or CRT-P upgrade. Methods Patients with a previously implanted conventional pacemaker (PM) developing heart failure (HF) despite optimal medical treatment and high rates of RVP, were included. Altogether 270 patients were investigated, 83 (30.7%) upgraded to CRT-D, 187 (69.3%) to CRT-P in our retrospective registry. The primary endpoint was all-cause mortality, secondary endpoints were malignant VAs and implantation-related complications. Results CRT-D upgrade patients were more likely to be males, have a favourable renal function and lower left ventricular ejection fraction (LVEF). During the median follow-up time of 3.7 years, 25 (30.1%) of CRT-D and 131 (70.1%) of CRT-P upgrade patients reached the primary endpoint. The CRT-D upgrade group showed a lower risk of all-cause mortality in the total cohort (HR: 0.55; 95% CI: 0.38–0.78; p=0.004) and in the ischaemic subgroups compared to CRT-P. After adjustment, CRT-D, ischaemic HF aetiology and LVEF have been confirmed as independent predictors of all-cause mortality. Malignant VA occurrence was higher among CRT-D patients (10.8% vs 1.1%; p=0.001), while no difference was observed in the rate of complications between the two patient groups. However, lead removal was performed more frequently (13.3% vs 1.1%; p&amp;lt;0.001) during CRT-D upgrade procedures compared to CRT-P. Conclusions Patients among the total and ischaemic HF aetiology subgroup benefited more from the CRT-D upgrade, although VAs and lead removal were more common than in the CRT-P group. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by the ÚNKP-20-3-I-SE-43 New National Excellence Program if the Ministry for Innovation and Technology in Hungary. Project no. NVKP_16-1–2016-0017 (“National Heart Program”) has been implemented with the support provided by the National Research, Development and Innovation Fund of Hungary, financed under the NVKP_16 funding scheme. The research was financed by the Thematic Excellence Programme (2020-4.1.1.-TKP2020) of the Ministry for Innovation and Technology in Hungary, within the framework of the Therapeutic Development and Bioimaging thematic programmes of the Semmelweis University. All-cause mort of pts after UPG