Single-chamber Pacemaker Implantation Research Articles

Trends in adoption of extravascular cardiac implantable electronic devices: the Dutch cohort

Abstract Introduction Conventional implantable cardioverter-defibrillators (ICDs) and pacemakers carry a risk of mainly pocket- and lead-related complications. To avoid these complications, extravascular devices (EVDs) have been developed, such as the subcutaneous ICD (S-ICD) and leadless pacemaker (LP). However, data on the actual adoption of EVDs for patient or center characteristics is lacking. Purpose To assess real-world nationwide trends in adoption of EVDs in the Netherlands. Methods Using the Netherlands Heart Registration, all consecutive patients with a de novo S-ICD or conventional single-chamber ICD implantation between 2012-2020, or with a de novo LP or conventional single-chamber pacemaker implantation between 2014-2020 were included. Trends in adoption of EVDs are described for different patient and hospital characteristics (tertiles of device-implanting volume and whether cardiothoracic surgery back-up was available). Differences between patients with EVDs and non-EVDs and differences between implanting centers of EVDs and non-EVDs were tested for by Student’s T-test, Chi-square and Fisher’s exact test. Trends in adoption over time were calculated with linear and logistic regression analysis. Results From 2012-2020, 2190 S-ICDs and 10683 conventional ICDs were implanted; from 2014-2020, 712 LPs and 11103 conventional pacemakers were implanted. The general adoption of both increased (S-ICDs, 8% to 21%; LPs, 1% to 8%), but the increase seems to reach a plateau (Fig. 1). S-ICD recipients were younger than conventional ICD recipients (p<0.001) and more likely to be female (p<0.001); LP recipients were younger than conventional pacemaker recipients (p<0.001) and more likely to be male (p=0.03). Both S-ICDs and LPs were mainly implanted in high-volume centers with thoracic surgery on-site (Fig. 2). Conclusions In this nationwide study we observed a relative quick adoption of innovative EVDs with a plateau after approximately 4 years. The relative adoption of S-ICDs is especially high in younger patients. EVDs are overall mainly implanted in high-volume centers with cardiothoracic surgery available. As LPs can only be implanted in centers with cardiothoracic surgery in the Netherlands, this may have limited its adoption.

EVALUATION OF EARLY OUTCOMES OF PERMANENT PACEMAKER IMPLANTATION IN HYPERTENSIVE PATIENTS WITH BRADYARRHYTHMIAS

Objective: This study aims to describe the clinical characteristics and the features of bradyarrhythmias on 24-hour Holter monitoring and to evaluate the early outcomes of permanent pacemaker implantation in hypertensive patients with bradyarrhythmias. Subjects and method: This cross-sectional study was conducted on 57 subjects with hypertension and bradyarrhythmias who were indicated for permanent pacemaker implantation. Results: The most common clinical symptoms recorded were fatigue, dizziness, and chest pain, accounting for 47.4%, 45.6%, and 42.1% respectively. The majority of patients had sinus node dysfunction (73.7%) and most underwent dual-chamber permanent pacemaker implantation (87.7%). The 24-hour Holter monitoring results showed that 42.1% had sinus atrial block - sinus pause in the sinus node dysfunction group and 15.8% of patients had third-degree atrioventricular block (AV block) in the AV block group. A good treatment outcome was observed in 72.0% of cases. Age > 70 (OR: 6.1; 95% CI: 1.2-30.1), female gender (OR: 4.2; 95% CI: 1.2-15.4), and single-chamber pacemaker (OR: 8.9; 95% CI: 1.5-52.1) were associated with a higher risk of moderate to poor treatment outcomes. Conclusion: Permanent pacemaker implantation generally tends to have good short-term outcomes. However, it should be noted that older age, female, and single-chamber pacemaker implantation in association with worse outcomes.

Transvenous Compared With Leadless Pacemakers: A meta-analysis comparing TP versus LP.

This study aims to compare the effectiveness of leadless pacemakers (LPs) and transvenous pacemakers and to examine the safety of both methods. We included patients undergoing single-chamber pacemaker implantation, either LP or TVP. Our outcomes were successful implantation rate, major complication, vascular injury, tamponade, and pneumothorax. We performed a double-arm analysis comparing LP versus TVP, with risk ratio (RR) and 95% confidence interval. A total of 10 studies were included in this meta-analysis. Regarding efficacy endpoints, RR revealed no significant difference between the LP and transvenous pacemaker groups in terms of successful rate of implantation (RR = 1.00; P = 0.77). Regarding safety outcomes, LP experienced lower incidence of major complications (RR = 0.47; P = 0.01), infection (RR = 0.24; P = 0.001), and tamponade (RR = 0.36; P = 0.01). There was no significant difference between both groups regarding pneumothorax (RR = 0.35; P = 0.22) and vascular injury (RR = 1.55; P = 0.25). The study findings suggest that both LPs and TVPs have similar effectiveness. Moreover, the incidences of pneumothorax, vascular injuries, and major complications were found to be comparable between the 2 methods. However, LPs were found to have lower rates of infection and tamponade.

First month global longtudinal strain for predicting early pacemaker-induced left ventricular dysfunction (PIVD) six month after pacemaker implantation

Abstract Background Pacemaker-induced ventricular dysfunction (PIVD) and pacemaker-induced cardiomyopathy (PICM) emerged as a complication following right ventricular permanent pacemaker (PPM) implantation, showing a great occurrence in the first year. Finding an early predictor of PIVD and PICM is crucial in order to alleviate mortality, morbidity, and increase health-care cost efficiency. Purposes to find new predictor by analyzing effect of first month GLS using 2D-speckle tracking echocardiography and reduction of left ventricular ejection fraction (LVEF), known as PIVD, in the first 6 month after PPM implantation. Methods A single center, prospective cohort study was conducted to all patients with normal LVEF, indicated for PPM implantation. Data of GLS was measured before and after one month of PPM implantation. Data of LVEF was measured before and six month after PPM implantation. The change of GLS in one month after PPM implantation was measured as delta GLS, and the change of LVEF in six month was measured as delta EF. Results Fifty-three patients from May 2018 until October 2020 was enrolled for this study based on inclusion and exclusion criteria. Patient’s baseline characteristics show 62±14 years of age, most of them had hypertension (54.7%) and had single chamber pacemaker implantation (81.1%). Study analysis reveals that ejection fraction (EF) reduce significantly after six months pacemaker implantation (66,5±5,6% become 60,7±10.7%; p= <0,00001). There were 6 patients (11.3 % ) suffering PICM. Correlation analysis between the change of GLS in the first month and the change of LVEF in the first six months after PPM implantation was statistically significant with moderate correlation (p<0.00001; r= -0.486). Linear regression analysis shows that every 1 point decrease of first month GLS, affecting 1.83 point decrease of sixth month LVEF (b= -0.1837, p=<0.00001). Conclusion There is significant moderate correlation between the change of GLS in the first month and early reduction of LVEF in the first 6 months after PPM implantation.The Scheme of Research Sampling Method

Slittable sheath supported right ventricular pacing lead implantation in persistent left superior vena cava with absent right superior vena cava: a case report

BackgroundPersistent left superior vena cava (PLSVC) is the most common variant of systemic venous drainage. In the absence of the right superior vena cava (RSVC), implantation of a right ventricular pacing lead may be challenging. Therefore specific implantation techniques and experiences in PLSVC are worth reporting.Case presentationWe present a case report of a 90-year-old Caucasian female patient with PLSVC during single chamber pacemaker implantation due to the third-degree atrioventricular block. With common implantation techniques, we did not even reach the right ventricle. Therefore slittable CPS Direct ™ Universal sheath was employed to overcome the acute angle from PLSVC to tricuspid valve and ensure more fixation stability for longer 100-cm right ventricular lead placement.ConclusionThis case demonstrates safe implantation of 100-cm long right ventricular bipolar active fixation pacing lead using common slittable CPS Direct ™ Universal sheath after failed attempts with „C“ and „J“ stylet shaped electrode. This sheath provides different angle towards tricuspid valve and more fixation stability in patient with PLSVC and absent connection to right atrium.

P190 TWIDDLER’S SYNDROME IN A 96–YEAR–OLD PATIENT TREATED BY REPOSITIONING THE VENTRICULAR LEAD

Abstract A 96–years–old woman was admitted to our cardiological intensive care unit in December 2022 with atrioventricular dissociation, with a junctional ventricular escape rhythm at a rate of 38 beats per minute, and an atrial rhythm dissociated from the ventricular rhythm, at a rate of 80 beats per minute (Figure 1). The patient had a history of third–degree atrioventricular block, effectively treated with single–chamber pacemaker implantation (Assurity MRI SR, Abbott), operation performed approximately 10 months before access, in February 2022. The patient underwent a chest X–ray, which showed "coiling" of the ventricular catheter in the pacemaker pocket area (left subclavicular), with macroscopic dislocation of the ventricular electrode, which had its distal tip in the right atrium (Figure 2). Therefore, the clinical case was typical of Twiddler‘s syndrome. The patient would therefore have undergone revision surgery. An attempt was made to reposition the original lead, with passive fixation (Isoflex 1948/58, Abbott), by inserting a "straight" stylet, a procedure which was done effectively. The ventricular lead was repositioned in the right ventricular apex. The detected parameters were optimal (sensing 7 mV, ventricular barrier threshold 0.5 mV/0.4 ms, impedance 797 Ohm). The result was considered acceptable. The remainder of the hospital stay was without complications. The patient was discharged on the fifth day in good general condition. Twiddler syndrome is defined as a dislocation of one or more catheters, resulting in the catheters "coiling" in the pocket of the device. It is usually related to the manipulation of the generator by the patient itself. It usually occurs within a year of implantation and is usually more common in females, the elderly, the obese, pediatric patients, or patients with psychiatric disorders. The identification of patients at risk for this pathology, the adequate education of the patient and family regarding the management of the device, the use of catheters with active fixation, as well as the fixation of the generator device to the pectoral muscle, through non–absorbable sutures. In the case described, the patient denied manipulation of the device, which however could not be excluded, given the age of the patient.

Immediate single-chamber pacemaker implantation in a 2-hour-old infant with complete congenital atrioventricular block.

Immediate single-chamber pacemaker implantation in a 2-hour-old infant with complete congenital atrioventricular block.

Evaluation of left ventricular dysfunction after single-chamber pacemaker implantation in patients with normal left ventricular function in a tertiary care institution in South India: An observational study

Evaluation of left ventricular dysfunction after single-chamber pacemaker implantation in patients with normal left ventricular function in a tertiary care institution in South India: An observational study

Conventional single-chamber pacemakers versus transcatheter pacing systems at long-term follow-up

Abstract Background Leadless pacemakers systems (LPM), have demonstrated safety and efficacy at mid-long term follow-up. There are still issues that cannot be completely avoided with conventional transvenous pacemaker (VVI) such as infectious or pocket related complications in which LPM are clearly superior. Purpose The aim of the study was to compare the clinical and device performance between LPM and VVI in a one-center long-term follow-up. Methods This was a prospective, observational, one-center study. We include all patients with a single chamber pacemaker implantation from June 1 2015 to March 1 2022 to complete a long-term follow-up. All clinical, electrical and echocardiographic characteristics, including electrical parameters, complications and mortality, were described. Results We included 245 patients with VVI pacemakers and 315 LPM. Mean age was 79.6±6.6 in LPM and 83.5±8.9 y/o in VVI pacemakers. All clinical, electrical and echocardiographic characteristics are described in Table 1. Electrical parameters of LPM were stable at long-term follow-up. There were a total of 7 complications in LPM and 17 in VVI pacemakers (p=0.006). There were no significant differences between major complications but there were in minor complications as shown in Table 2. There were no significant differences in mortality between both groups, but there was one death related to endocarditis in a VVI pacemaker patient during the follow-up (40,3±10 months). Conclusions In our study, there were no significant differences in terms of mortality and major complications between LMP and VVI at long-term follow-up. We consider our study supports the results in favor of the safety and effectiveness of LPM in the long-term. Funding Acknowledgement Type of funding sources: None.

P380 THE REEL‘S SYNDROME : A RARE COMPLICATION AFTER PACEMAKER IMPLANTATION

Abstract We report the case of a 83–year–old male who underwent single chamber pacemaker implantation in another center for bradyarrhythmia (atrial fibrillation) symptomatic for syncope. A ventricular lead was implanted in the apical septum, the post–procedural posterior–anterior chest radiograph showed correct placement of the leads and generator. Approximately 4 months after the implant, the patient came to our observation for repeated electric pulsations in his left shoulder. The patient was affected by mild dementia and was asymptomatic except for the presenting symptomatology, in particular he denied a history of syncope. The ECG showed arrhythmia due to atrial fibrillation, ventricular undersensing, and lack of ventricular capture (Figure 1). The chest X–ray showed the complete dislodgement of the ventricular lead tip apparently into the vein secondary to the rotation of the pulse generator on its transverse axis with consecutive coiling of the lead (Fig. 2). These findings were consistent with Reel syndrome The patient was admitted to undergo a lead repositioning attempt in consideration of the recent first implant. During the surgery, however, it was shown that the lead was completely displaced from the venous system, near the pectoral muscle. This extreme dislocation of the lead has been related to the electric pulsations felt by the patient. We proceeded with a new re–implantation of the lead and removal of the previous one. The lead was firmly tied to the pectoral muscle with 2 silk points with slight traction control of optimal fixation. Reel‘s syndrome is a variant of the better known Twiddler syndrome, characterized by the coiling of catheters along the transverse axis of the pacemaker. It is often a complication due to the manipulation of the generator by the patient, unlike Twiddler syndrome it occurs early and the leads remain intact. This syndrome is one of the most serious complications of pacemaker or defibrillator implants, it can be potentially fatal due to lack of therapy in the case of defibrillators, or asystole in pacemaker–dependent patients.

Novel Radiomics Features for Automated Detection of Cardiac Abnormality in Patients with Pacemaker.

Cardiac pacemakers are used in the treatment of patients with symptomatic bradycardia. The pacemaker paces the heart at the predetermined rate to maintain uninterrupted cardiac activity. Usually, pacemaker lead will be connected to the right atrium (RA) and right ventricle (RV) in dual-chamber pacemaker implantation and RV alone in single-chamber pacemaker implantation. This alters the route of proper conduction across the myocardial cells. The cell-to-cell conduction transmission in pacing delays the activation of selected intraventricular myocardial activation. Pacing-induced cardiomyopathy (PICM) is most commonly defined as a drop in left ventricle ejection fraction (LVEF) in the setting of chronic, high-burden right ventricle (RV) pacing. Currently, very few effective treatments are standard for PICM which rely on the detection of the RV pacing. Such treatments have primarily focused on upgrading to cardiac resynchronization therapy (CRT) when LVEF has dropped. However, the early and accurate detection of these stress factors is challenging. Cardiac desynchrony and interventricular desynchrony can be determined by various echocardiographic techniques, including M-mode, Doppler method, tissue Doppler method, and speckle tracking echocardiography which is subjective measures and shows a significant difference between RV and LV preejection period where the activation of LV is delayed considerably. Computer-aided diagnosis (CAD) is a noninvasive technique that can classify the ultrasound images of the heart in pacemaker-implanted patients and healthy patients with normal left ventricular systolic function and further detect the variations in pacemaker functions in its early stage using heart ultrasound images. Developing such a system requires a vast and diverse database to reach optimum performance. This paper proposes a novel CAD tool for the accurate detection of pacemaker variations using machine learning models of decision tree, SVM, random forest, and AdaBoost. The models have been used to extract radiomics features in terms of textures and then screened by their Relief-F scores for selection and ranking to be classified into nine groups consisting of up to 250 radiomics features. Ten best features were fed to the machine learning models. The R-wave dataset achieved a maximum test performance accuracy of 97.73% with four features in the random forest model. The T-wave dataset achieved a maximum test performance accuracy of 96.59% with three features in the SVM model. Our experimental results demonstrate the system's robustness, which can be developed as an early and accurate detection system for pacing-induced cardiomyopathy.

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

Abstract 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.

An Interesting Case of Acute Asymptomatic Lead Perforation of a Permanent Cardiac Pacemaker

Acute complications of pacemaker implantation such as lead dislodgement, pneumothorax, and myocardial perforation are not uncommon. Management of these usually requires reintervention. We herein describe lead perforation after a single chamber pacemaker implantation, which was successfully managed conservatively. This case underscores that vigilant monitoring post lead perforation can avoid a redo procedure.

Abstract 17088: In-Hospital Complications and Outcomes of Leadless Pacemaker Implantation: A Propensity-Score Matched Analysis From Nationwide Database

Introduction: There are no randomized controlled trials that compared the outcomes of leadless pacemaker (L-PPM) implantation with transvenous pacemaker (TV-PPM) and there is scarcity of data on real world outcomes. Methods: We queried National Inpatient Sample to identify all adult patients who had primary discharge diagnosis of conduction disorders or tachy-arrhythmias and excluded patients who had a concomitant procedure for valve replacement, coronary artery bypass grafting, ablation and/or cardiac implantable electronic device removal so that complications can be attributed to the pacemaker implantation. We included only procedures from November 2016 to December 2017 as Micra was the only available L-PPM during that period. For the comparison cohort we selected patients, during the same time period, who had a procedure code for single chamber pacemaker implantation in conjunction with right ventricular lead placement. We performed 1:1 propensity score matching and the variables used for matching are marked with asterisk in Table 1. All the codes used to identify complications has been previously validated from the Micra Post-approval registry and Coverage with Evidence Study. Results: Total of 1,305 patients for L-PPM and 13,905 patients in the TV-PPM group were included. Baseline characteristics with standardized mean difference before and after matching are shown in Table 1. Briefly, patients in L-PPM group were younger but had higher co-morbidities compared to TV-PPM group. The complications before and after matching are shown in Table 2. Conclusions: In conclusion, we found no significant difference between in-hospital complications after propensity score matching, with the exception of deep venous thrombosis. There was no difference between length of stay but cost for L-PPM was significantly higher. In this real-world analysis, we found that the leadless PPM implantation is safe in comparison to transvenous PPM.

P1466Leadless pacemaker mid and long term follow-up in a single center-study

Abstract Introduction and objectives Initial results of Leadless pacemakers (LPM) has been promising in worldwide, nevertheless there are still no long term experience published, so the objective of our study was to evaluate electrical parameters at mid and long term follow-up, describing as well total complications and mortality in a single center-study. Methods This was a prospective, observational clinical trial that included 183 consecutive patients, with an indication for a single-chamber pacemaker implantation. Results All successful implantation included a total of 183 patients with a mean age of 79,2 ±6,6 years (range 54-93y/o); 111 (60,6%) were men and more frequent rhythm was permanent atrial fibrillation (160), including those in which a node ablation was performed in the same procedure (22). Clinical and echocardiographyc characteristics are described in table 1.Mean follow-up was of 26 ±10 months including: 64 patient at 24 months, 46 at 36 months and 7 patients at 48 months. Electrical parameters are represented in figure 1, which were stable and flawless at long term follow-up. Total complications were 3,3%, with only 2 patient requiring surgery for resolution (1,7%), and all were acute during LPM implantation. A total of 17 patients (9,3%) died with no relation to pacemaker. Conclusions In our experience, leadless pacemakers electrical performance continues stable, appropriate at long term follow-up, and no other complications developed. Baseline Characteristics of Patients Age(years) 79.2 ± 6.6[54-93] Male gender, n (%) 118 (60.6%) Hypertension, n (%) 149 (81.7%) Diabetes mellitus, n (%) 64 (34.9%) COPD, n (%) 33(18.3%) Renal dysfunction, n (%) 30 (16.7%) Valvular disease, n (%) 74 (41.1%) Atrial Fibrillation, n (%) 161 (98.0%) LVEF(%) 60.0 ± 8 OAC, n (%) 123(67.2%) NOAC, n (%) 23 (10.0%) Abstract Figure. Electrical performance

P6549Conventional single lead ventricular pacemaker against leadless pacemaker system in real-world patients: prospective one center study. CARDIOCHUS Registry

Abstract Background As more experience is obtained with leadless pacemakers systems (LPM), a great group of patients is considered for its implantation. There are issues that cannot be completely avoided with conventional transvenous pacemaker (VVI-PM) such as infectious or pocket related complications in which LPM are clearly superior. Purpose The aim of the study was to compare the clinical and device performance between LPM and VVIPM in the same period of time in a “real-world” population. Methods We performed a prospective, observational, one center study, including all patients with a single chamber pacemaker implantation within 3 years (June 2015-December 2018) and its mid-term follow-up. All clinical, electrical and echocardiographic characteristics, as well as implantation characteristics and complications, were described. Results We included a total of 339 patients with transvenous pacemakers, 195 patients with VVI-PM and 144 LPM. There were no significant differences in mortality between both groups during the follow-up (12,3±10 months), Figure 1. Although there were no significant differences in major complications (P-value 0,54), the number of total complications was lower in the LPM group (P-value 0,01) at the expense of fewer minor ones (P-value 0,02), Table 1. Table 1. Complications TVP (195) LPM (144) P value Major complications 11 (5.6%) 6 (4.2%) 0.54 Minor complications 10 (5.1%) 0 (0.0%) 0.01 Total Complications 21 (10.7%) 6 (4,2%) 0.02 Figure 1 Conclusions In our study, during the med-term follow-up, there were no significant differences in terms of mortality and the major complications between LMP and VVI-PM. Although, the number of minor complications were less with the LMP.

Late myocardium perforation following single-chamber pacemaker implantation

Late myocardium perforation following single-chamber pacemaker implantation

Pacemaker therapy in low-birth-weight infants.

Infants born with complete atrioventricular block (CAVB) and fetal bradycardia are frequently born with low birth weight. Three low-birth-weight CAVB infants underwent temporary pacemaker implantation, followed by permanent single-chamber pacemaker implantation at median body weights of 1.7 and 3.2 kg, respectively. All infants caught up with their growth curves and had >3 years of estimated residual battery life. This two-stage strategy was successful in facilitating permanent pacemaker implantation in low-birth-weight babies. Placement of single-chamber pacemaker on the apex of the left ventricle appears to be associated with longer battery lifespan.

The Micra Leadless Transcatheter Pacemaker. Implantation and Mid-term Follow-up Results in a Single Center

Introduction and objectivesCurrently, studies on the leadless pacemaker (Micra) have mostly been limited to clinical trials with less than 6 months’ follow-up and they often fail to reflect real population outcomes. We sought to evaluate electrical parameters at implantation and chronologically during follow-up, as well as the safety of this new technique. MethodsThis prospective, observational study included 30 consecutive patients, all ≥ 65 years, with an indication for single-chamber pacemaker implantation. ResultsSuccessful implantation was accomplished in all patients referred for leadless implantation. The mean age was 79.4±6.4 years (range, 66-89 years); 20 (66.6%) were men and 28 had permanent atrial fibrillation (93.3%); 1 had atrial tachycardia and 1 had sinus rhythm. Concomitant atrioventricular node ablation was performed immediately after implantation in 5 patients (16.6%), and implantation was performed after transcatheter aortic valve implantation in 2. The procedure was performed under an uninterrupted anticoagulation regimen (maximum INR 2.4) in 23 patients (76.6%). With the exception of 1 moderate pericardial effusion without tamponade, there were no severe complications. The mean follow-up was 5.3±3.3 months and 4 patients had more than 1 year of follow-up. Sensing and pacing parameters were stable both at implantation and during the short- to mid-term follow-up. ConclusionsImplantation of leadless pacemakers is feasible, safe and provides advantages over the conventional system. Further studies with longer follow-up periods will be needed before these devices become widely used in routine clinical practice.

Marcapasos transcatéter sin cables Micra. Resultados del implante y seguimiento a medio plazo en un centro

Introduction and objectivesCurrently, studies on the leadless pacemaker (Micra) have mostly been limited to clinical trials with less than 6 months’ follow-up and they often fail to reflect real population outcomes. We sought to evaluate electrical parameters at implantation and chronologically during follow-up, as well as the safety of this new technique. MethodsThis prospective, observational study included 30 consecutive patients, all ≥ 65 years, with an indication for single-chamber pacemaker implantation. ResultsSuccessful implantation was accomplished in all patients referred for leadless implantation. The mean age was 79.4±6.4 years (range, 66-89 years); 20 (66.6%) were men and 28 had permanent atrial fibrillation (93.3%); 1 had atrial tachycardia and 1 had sinus rhythm. Concomitant atrioventricular node ablation was performed immediately after implantation in 5 patients (16.6%), and implantation was performed after transcatheter aortic valve implantation in 2. The procedure was performed under an uninterrupted anticoagulation regimen (maximum INR 2.4) in 23 patients (76.6%). With the exception of 1 moderate pericardial effusion without tamponade, there were no severe complications. The mean follow-up was 5.3±3.3 months and 4 patients had more than 1 year of follow-up. Sensing and pacing parameters were stable both at implantation and during the short- to mid-term follow-up. ConclusionsImplantation of leadless pacemakers is feasible, safe and provides advantages over the conventional system. Further studies with longer follow-up periods will be needed before these devices become widely used in routine clinical practice.Full English text available from: www.revespcardiol.org/en