Leadless Transcatheter Pacemaker Research Articles

Transfemoral leadless pacemaker implantation after tricuspid valve surgery and intervention

Abstract Background and Purpose Pacemaker (PM) implantation after surgical or transcatheter tricuspid valve (TV) repair or replacement may be challenging. Transcatheter leadless pacemaker (LPM) implantation has become a routine procedure and is frequently adopted in patients without the need for an atrial lead, in cases with cardiac implantable device infection or in patients with marked comorbidities. The use of LPM in patients with previous TV repair or replacement has only been described in singular cases in literature. We present our single center experience of LPM implantation after TV repair. Methods Patients with a history of TV repair or replacement who underwent LPM in our institution between 01/2020 and 11/2023 were retrospectively analyzed. All patients underwent routine clinical follow-up investigations including LPM interrogation and transthoracic echocardiography to assess for TV status. For LPM implantation right anterior oblique (RAO) and left anterior oblique (LAO) caudal fluoroscopy projections were utilized to enable LPM device passage across the TV. Results The study population consisted of 10 patients (9 females, mean age 74.0±10.0 years). Two patients had a history of surgical TV annuloplasty repair and two patients a history of surgical valve replacement, four patients of transcatheter TV repair (one through the mitral clip), one patient of transcatheter valve-in-ring bio prosthesis implantation prosthesis after previous surgical ring deployment and one patient transcatheter TV replacement (Figure1). All patients suffered from permanent atrial fibrillation previous to implantation procedures. Three patients were on chronic hemodialysis therapy before LPM implantation. LPM systems were successfully implanted in all cases with a mean procedure time of 43.5±26.5 minutes and a mean fluoroscopy time of 5.9±5.5 minutes and a radiation dose of 1148,7±1424,9 cGy·cm2. For fluoroscopically guided TV crossing a mean LAO angle of 43.6±14.1° (range 22 to 53°) and caudal angle of 8.5±6.9° (range 0 to 20°) was utilized (Figure 2). The LPM device was positioned in the first positioning attempt in a right ventricular high septal localization in 8 cases. Mean pacing threshold was 0.36±0.07 V at 0.25 ms, with a mean sensing amplitude of 10.5±2.9 mV and a mean of 853±324 Ohms pacing impedance. No periprocedural complications occurred. Mean duration of follow-up was 8.1±9.2 months. There were no newly developed TV regurgitations noted. Pacing thresholds (0.37±0.1 V/0.25 ms), sensing amplitude (11.8±4.5 mV) as well as pacing impedances (865±365 Ohms) remained stable until the last follow-up investigation. Conclusion LPM implantation was feasible in patients with a history of TV repair or replacement. LPM implantation was safe and effective in various modalities of TV repair. LPM may be an alternative to conventional pacemaker implantations as well as surgical lead placement in selected patients.Figure 1.Figure 2.

Working Around: The Use of AngioVac and Micra Transcatheter Leadless Pacemaker Implantation in a Critically Ill Patient Receiving Extracorporeal Membrane Oxygenation.

The use of extracorporeal membrane oxygenation (ECMO) in critically ill patients has been on the rise in recent years. While ECMO has provided substantial benefit to patients who need cardiopulmonary support, its required use of large-bore catheters in major blood vessels often precludes the use of other transcatheter therapies. In this article, we demonstrate that two transcatheter procedures, AngioVac right-sided cardiac thrombus removal and Micra leadless pacemaker placement, both requiring large bore access, can both be safely and effectively implemented in patients who are dependent on ECMO to maintain cardiopulmonary function.

PP41 Using Medicare Claims Data To Support Reimbursement Of A Novel Leadless Pacing System For The Management Of Bradycardia

IntroductionThe Micra Transcatheter Pacing System (Micra TPS) is a single-chamber transcatheter leadless pacemaker (LPM). LPMs do not require leads or a subcutaneous pocket, which represent the primary sources of device-related complications with conventional transvenous pacemakers (TVPMs). Complications such as infections and lead dislodgements cause significant patient burden, which have significant economic consequences. Running a randomized controlled trial (RCT) to estimate risk differences of infrequent events requires large sample sizes and long follow-up periods. Real-world observational data, while informative, requires an appropriate study design and statistical adjustments to control for potential biases.MethodsThe Micra Coverage with Evidence Development (CED) study was a cohort study of LPM versus TVPM based on US Medicare claims data of 16,431 patients with 2-year follow up (LPM: n=6,219; TVPM: n=10,212). Propensity score matching (PSM) was applied to account for differences in baseline characteristics. As no RCT was identified in the literature, this study was presented to the Australian payer as the primary source of clinical evidence, upon which a cost-utility analysis was conducted.ResultsAfter PSM, the CED study demonstrated significantly more complications with TVPM versus LPM with adjusted rates of 6.5 percent and 4.6 percent (p<0.001). Significant differences favoring LPM (p<0.01) were observed in device breakdown (1.4% vs 2.0%), dislodgment (0.4% vs 1.2%) and infection (<0.1% vs 0.6%). Based on these findings, a claim of superior safety was accepted by Medical Services Advisory Committee (MSAC) to support reimbursement. In making this decision, MSAC considered that the large sample size and propensity weighting overcame some of the potential biases and the magnitude of the benefit supported cost-effectiveness relative to TVPM.ConclusionsThe lack of a sufficiently powered RCT with an extended follow-up period can mean the impact and benefits of new technologies that reduce clinically important adverse events of relative infrequency are not formally incorporated into payer decision making, particularly where RCTs are a requirement. A well-designed observational study can provide valuable, real-world evidence to support a HTA for reimbursement decisions.

Removal of a leadless pacemaker using a 2.5cc syringe and silk thread during surgical treatment of infective endocarditis

Removal of a leadless pacemaker using a 2.5cc syringe and silk thread during surgical treatment of infective endocarditis

Leadless transcatheter pacemaker: Indications, implantation technique and peri-procedural patient management in the Italian clinical practice

BackgroundSafety and efficacy of leadless pacemakers (L-PM) have been demonstrated in multiple clinical trials, but real-world data on patient selection, implantation technique, and peri-procedural patient management in a clinical practice setting are lacking. MethodsConsecutive patients undergoing L-PM implantation in 14 Italian centers were followed in a prospective, multicentre, observational project. Data on baseline patient characteristics, clinical indications, implantation procedure, and peri-procedural patient management were collected. The rate and nature of device-related complications were also recorded. ResultsA total of 782 L-PM patients (68.4% male, 75.6 ± 12.4 years) were included in the analysis. The main patients-related reason leading to the choice of implanting a L-PM rather than a conventional PM was the high-risk of device infection (29.5% of cases). The implantation success rate was 99.2%. The median duration of the procedure was 46 min. In 90% of patients the device was implanted in the septum. Of patients on oral anticoagulant therapy (OAT) (n = 498) the implantation procedure was performed without interrupting (17.5%) or transiently interrupting OAT without heparin bridging (60.6%). During a median follow-up of 20 months major device-related complications occurred in 7 patients (0.9%): vascular access-site complications in 3 patients, device malfunction in 2 patients, pericardial effusion/cardiac tamponade in one patient, device migration in one patient. ConclusionsIn the real world setting of Italian clinical practice L-PM is often reserved for patients at high-risk of infection. The implantation success rate was very high and the risk of major complications was low. Peri-procedural management of OAT was consistent with available scientific evidence.

Abstract 12685: Feasibility and Safety of Vascular Closure Devices After Undergoing Leadless Pacemaker Implantation

Introduction: Transcatheter pacing systems have recently emerged as a safe and effective alternative in treating patients who require right ventricular pacing therapy. Traditionally, the right femoral venous was the preferred insertion site for the 23 French Micra introducer catheter due to the manufactured design of the delivery system. Vascular closure of the venous access has been performed with figure 8 closure technique and manual pressure . There is no data supporting the use of closure devices in this specific procedure. The purpose of this study was to assess the feasibility and safety of vascular closure devices after undergoing implantation of the leadless pacemaker device. Methods: One hundred and eighty ( 180 ) consecutive patients who had undergone implantation of a Micra transcatheter pacing were evaluated. One hundred and sixty eight ( 168 ) patients had traditional vascular closure after implantation and twelve ( 12 ) received the Perclose vascular closure device for the femoral venous access . A t-test analysis was used to compare patient demographics total procedure times and complications rates Results: None of the 180 patients suffered complications during the procedure. The mean procedure time using the traditional figure eight technique was 21.24 min versus 30.67 min (P = 0.01) by the closure device . The mean number of recaptures required for the patients undergoing the traditional venous closure was 0.48 vs. 0.67 (P = 0.70) by the closure device Conclusions: The Perclose device appears safe and feasible alternative for the vascular closure after implantation of the Micra transcatheter leadless pacemaker system. This approach tends to have longer procedure times

TTE guided synchronization to optimize AV synchronous leadless pacemaker programming.

Transvenous pacemakers are associated with major complications [1]. Transcatheter leadless pacemaker has reduced the incidence of these complications and the recent accelerometer based atrial sensing algorithm permits restoration of atrioventricular synchrony [1]. We report utilizing cardiac output measurements using Transthoracic Echocardiography (TTE) to determine optimal programming for leadless pacemaker.

Quantification of artifacts during cardiac magnetic resonance in patients with leadless Micra pacemakers.

When cardiac magnetic resonance (MR) is performed after previous leadless transcatheter pacemaker implantation, an image distortion has to be expected in the heart region and evaluation of myocardial tissue can be affected. In this clinical prospective study, we aim to assess the extent and impact of this artifact on individual ventricular segments and compare it to conventional pacing devices. Total of 20 patients with leadless pacemaker placed in the right ventricle underwent cardiac MR imaging in a 1.5 Tesla scanner. A multiplanar segmentation was used to demarcate the left and right ventricular myocardium as well as the pacemaker-caused image artifact in systolic and diastolic time frames. Artifact size and its relative influence on myocardial segments were quantitatively assessed and expressed in AHA-17 model. Implanted leadless pacemaker caused an image artifact with a volume of 48 ± 5 ml. Most distorted were the apical septal (53 ± 23%), apical inferior (30 ± 18%), and midventricular inferoseptal (30 ± 20%) segments. The artifact intersection with basal and lateral segments was none or negligible (up to 2%). The portion of left ventricular (LV) myocardium affected by the artifact was significantly higher in systole (8 ± 4%) compared to diastole (10 ± 3%; p < .001). Implantation of leadless pacemaker represents no obstacle for cardiac MR imaging but causes an image artifact located mostly in septal, inferoseptal, and anteroseptal segments of apical and midventricular LV myocardium. With the exception of the apex, diastolic timing reduces the image distortion of all segments and improves global ventricular assessment.

A Predictive Model for the Long-Term Electrical Performance of a Leadless Transcatheter Pacemaker

This study sought to formulate a predictive model for describing the long-term electrical performance of Micra (Medtronic, Mounds View, Minnesota). The Micra leadless pacemaker is an alternative ventricular pacing option that avoids the pitfalls of transvenous leads. However, well-defined metrics to predict the long-term electrical performance of the device are lacking. We identified all patients who underwent successful Micra implantation enrolled in the investigational device exemption study, continued access study, or post-approval registry with complete 1-year post-implantation data or system revision due to elevated thresholds (N=1,843). The analysis endpoint was an elevated pacing capture threshold (PCT) at≥12months post-implantation, defined as≥2.0V at 0.24ms or an increase of≥1.5V from implantation or need for system revision due to elevated thresholds at≤12months post-implantation. We evaluated for univariate and multivariate associations between patient and device characteristics at implantation and for elevated thresholds at 12months. Among the total cohort, 75 patients (4.1%) had elevated thresholds at 12months; of these, 13 required system revisions. Predictors associated with elevated thresholds in univariate analysis included the total number of deployments (excluded from the multivariable model), impedance and PCT at implantation, male sex, history of diabetes, and ischemic cardiomyopathy. Multivariable regression modeling found that male sex, history of diabetes, implantation PCT of≥2 V, and impedance of<800 Ω were independent predictors of elevated PCT at 12months (all p<0.05). A history of diabetes, male sex, elevated PCT, and low impedance at implantation were independentpredictors of elevated thresholds at 12months. These metrics represent the foundation of a simple tooltoaid in procedural decision making.

Abstract 14856: Leadless Pacemaker Implantation in Patients With Paroxysmal Complete Atrioventricular Block

Introduction: Transcatheter pacing systems have recently emerged as a safe and effective alternative in treating patients who require right ventricular pacing therapy. Traditionally, patients with atrial fibrillation with slow ventricular response had been benefit from this therapy. More recent, patients with symptomatic paroxysmal complete AV block had been receiving these devices. At this moment there is no data available about the feasibility , safety or outcomes of leadless pacemaker in this subgroup of patients Objective: The aim of this study was to assess the feasibility safety and 1 year follow up of the transcatheter leadless pacemaker device in patients with paroxysmal complete AV block . Methods: One hundred and ten (110 ) consecutive patients who underwent implantation of a Micra transcatheter leadless pacemaker (LPM)and have been follow up for at least a year were evaluated . Forty one (41) of these patients had the device implanted after experiencing symptomatic paroxysmal complete AV block. A t-test analysis was used to compare patient demographics, total procedure times, complication rates and recaptures necessary during the procedure. Results: All the patients with symptomatic paroxysmal complete AV block were implanted successfully with the leadless pacemaker system ( LPN ) . None of the patients suffered complications during the procedures. Fifty three percent ( 53%) were female , mean age of 77 , mean procedure time was 21.1 min. The mean number of recaptures required were 0.48 . None of the patient experienced pacemaker syndrome or progress to complete AV block after 1 year of follow up Conclusion: Leadless pacemaker implantation appears to be a safe and feasible alternative for subjects with symptomatic paroxysmal complete AV block . Further studies are required in these subgroup of patients

Initial implantation experience and short-term follow-up results of implanting leadless intracardiac transcatheter pacing system

Objective: To explore the utility and safety of leadless intracardiac transcatheter pacing system. Methods: The study was a prospective observational study. Patients underwent Micra transcatheter pacing system in Beijing Anzhen hospital from December 2019 to January 2020 were enrolled. The baseline characteristics, platelet count, hemoglobin, anticoagulation and/or antiplatelet therapy, mean procedural time, average fluoroscopy time, number of deployment and electrical parameters (threshold, R-wave amplitude, impedance) were recorded. Ultrasonography of bilateral femoral and iliac veins was performed in all patients. Patients were followed including access site complication, adverse event and device evaluation at implant, hospital discharge, 1 and 3 months post-implant. R-wave≥5 mV, impedance between 400 and 1 500 Ω and threshold increase≤1.5 V than implant is considered a stable parameter. Femoral access site complications included hematoma, hemorrhage, pseudoaneurysm, and arteriovenous fistula. Adverse events included dislodgement, cardiac effusion/perforation and infection. Left ventricular end diastolic diameter and ejection fraction before and at 1 month after implant were reported. Results: Five patients were enrolled and pacemaker implantation was successful in all 5 patients. Patients were all males and the average age was (78.4±8.4) years. 2 patients received aspirin and clopidogrel therapy, 1 patient suffered from anemia and thrombocytopenia occurred in 1 patient. No stenosis, occlusion and vascular malformation of bilateral femoral and iliac veins was observed. The mean implant time was (39.6±1.7) minutes. The average fluoroscopy time was (9.2±1.3) minutes and the number of deployment was (1.40±0.55). Electrical parameters(threshold, R-Wave amplitude and impedance) were as follows: (0.40±0.10) V/0.24 ms, (10.80±3.72) mV and (822.00±162.23) Ω at implant; (0.45±0.07) V/0.24 ms, (13.04±2.41) mV, and (748.0±91.5) Ω at discharge, (0.40±0.06) V/0.24 ms, (14.26±4.11) mV, and (700.0±91.7) Ω at 1 month post-implant and (0.39±0.05) V/0.24 ms, 14.40±3.97 mV, and (682.0±96.0) Ω at 3 months post-implant, respectively. Threshold increase was ≤1.5 V compared to that during implantation, electrical parameters were acceptable and stable. There was no difference in LVEDD [(44.00±5.24) mm vs. (44.00±5.34) mm,P=1.000] and EF [(62.00±3.39)% vs. (62.20±3.56)%, P=0.861] before and 1 month post-implant. No incidence of access site complications, cardiac effusion/perforation, dislodgment or infections occurred during the 3 months. Conclusions: The leadless transcatheter pacemaker implantation performed in our study archived a high implant success rate and favorable safety profile as well as associated with low and stable pacing thresholds. The long-term safety and benefit of leadless pacemaker need to be evaluated in future clinical studies.

Visualization of Cardiac Perforation During Micra Transcatheter Leadless Pacemaker Implantation - A Lesson From Cadaver Training.

Visualization of Cardiac Perforation During Micra Transcatheter Leadless Pacemaker Implantation - A Lesson From Cadaver Training.

First transcatheter leadless pacemaker implantation in apediatric patient with agenetic disease.

Apediatric patient suffering from Marden-Walker syndrome, arare genetic disease, was referred to the authors' hospital for syncope due to bradycardia. Since this disease is associated with severe joint contractures, atranscatheter leadless pacing system (TPS) was chosen. Despite the small body size and complex anatomy, TPS implantation was feasible, demonstrating that it is asafe alternative in difficult venous access compared to aconventional pacemaker with increased risk of lead complications in these patients.

The Safety and Feasibility of Same-Day Discharge After Implantation of MICRA Transcatheter Leadless Pacemaker System.

Data suggests that same day discharge after implantation of trans-venous pacemakers is safe and feasible. We sought to determine whether same day discharge was feasible and safe following implantation of Medtronic MICRA leadless pacemakers. We retrospectively identified all patients undergoing MICRA placement at our institution between April 2014 to August 2018 (n=167). Patients were stratified into two groups: those discharged on the same day as their procedure (SD, n=25), and those observed for at least one night in the hospital (HD, n=142). The primary endpoint included a composite of major complications including: access site complications, new pericardial effusion, device dislodgement, and need for device revision up to approximately 45 days of follow up. SD and HD had similar age (75±13 vs. 75±13 years, p=0.923), prevalence of male sex (49 vs. 44%, p=0.669), and frequency of high-grade heart block as an indication for pacing (38 vs. 32%, p=0.596). There were more Caucasians in the SD group (72 vs. 66%, p=0.038). The rate of the composite endpoint was statistically non-significantly higher in the HD group (3.5% vs. 0.0%, p=1.00). The rates of each individual components comprising the composite endpoint were similar between groups. Our data suggest that in appropriately selected patients, same day discharge can occur safely following Micra leadless pacemaker implantation.

Leadless pacemaker implantation and concurrent atrioventricular junction ablation in patients with atrial fibrillation.

Atrioventricular junctional (AVJ) ablation and pacemaker implantation are indicated when pharmacotherapy fails to achieve adequate rate control in atrial fibrillation (AF). The purpose of our study is to assess the feasibility and safety of concurrent Micra leadless transcatheter pacemaker implantation and AVJ ablation. We retrospectively assessed patients who underwent Micra implantation and concurrent AVJ ablation at three institutions between August 2014 and March 2016. All patients and devices were followed at baseline and at 1, 3, 6, and 12 months postimplantion. Twenty-one patients with permanent AF (median age 77 [range: 62-88], female 15 [71.4%]) underwent successful Micra implantation followed by concurrent AVJ ablation. There was no device dislodgement or malfunction during the 12-month follow-up. Complete 12-month electrical performance data were available in 14 patients (67%). Among patients with the complete data set, median pacing thresholds at implant and at 1, 3, 6, and 12 months were 0.5 V (range: 0.25-0.88), 0.44 V (range: 0.25-2.0), 0.5 V (range: 0.25-1.63), 0.5 V (range: 0.25-1.13), and 0.5 V (range: 0.25-1.13) at a pulse width of 0.24 msec, respectively. Two patients died due to noncardiac causes during follow-up. There were no patients with major device-related complications. Concurrent Micra implantation and AVJ ablation is feasible and appears safe. There was no device dislodgement, malfunction, or significant pacing threshold rise requiring device reimplantation during the 12-month follow-up. This combined approach can be considered for patients with AF with suboptimal rate control who have failed AF catheter ablation and/or pharmacotherapy.

40Different implant locations of transcatheter leadless pacemaker and electrical performance

40Different implant locations of transcatheter leadless pacemaker and electrical performance

Transcatheter Leadless Pacemaker Implantation in a Patient with Recurrent Complications Following Transvenous Pacemaker Systems

Transcatheter Leadless Pacemaker Implantation in a Patient with Recurrent Complications Following Transvenous Pacemaker Systems

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.

Safety evaluation of a leadless transcatheter pacemaker for magnetic resonance imaging use

Increased magnetic resonance imaging (MRI) adoption and demand are driving the need for device patients to have safe access to MRI. The aim of this study was to address the interactions of MRI with the Micra transcatheter pacemaker system. A strategy was developed to evaluate potential MRI risks including device heating, unintended cardiac stimulation, force, torque, vibration, and device malfunction. Assessment of MRI-induced device heating was conducted using a phantom containing gelled saline, and Monte Carlo simulations incorporating these results were conducted to simulate numerous combinations of human body models, position locations in the MRI scanner bore, and a variety of coil designs. Lastly, a patient with a Micra pacemaker who underwent a clinically indicated MRI scan is presented. Compared to traditional MRI conditional pacemakers, the overall risk with Micra was greatly reduced because of the small size of the device and the absence of a lead. The modeling results predicted that the nonperfused temperature rise of the device would be less than 0.4°C at 1.5 T and 0.5°C at 3 T and that the risk of device heating with multiple device implants was not increased as compared with a single device. The clinical case study revealed no MRI-related complications. The MRI safety assessment tests conducted for the Micra pacemaker demonstrate that patients with a single device or multiple devices can safely undergo MRI scans in both 1.5- and 3-T MRI scanners. No MRI-related complications were observed in a patient implanted with a Micra pacemaker undergoing a clinically indicated scan.

136-41: Initial Real World Performance of Micra™ Leadless Transcatheter Pacemaker Anticipates Outstanding Battery Longevity

136-41: Initial Real World Performance of Micra™ Leadless Transcatheter Pacemaker Anticipates Outstanding Battery Longevity