Abstract Background Transvenous implantable cardioverter-defibrillators (TV-ICDs) improve survival in patients at risk for sudden cardiac death, but complications remain an important drawback. The ...subcutaneous ICD (S-ICD) was developed to overcome lead-related complications. Comparison of clinical outcomes of both device types in previous studies was hampered by dissimilar patient characteristics. Objectives This retrospective study compares long-term clinical outcomes of S-ICD and TV-ICD therapy in a propensity-matched cohort. Methods The authors analyzed 1,160 patients who underwent S-ICD or TV-ICD implantation in 2 high-volume hospitals in the Netherlands. Propensity matching for 16 baseline characteristics, including diagnosis, yielded 140 matched pairs. Clinical outcomes were device-related complications requiring surgical intervention, appropriate and inappropriate ICD therapy, and were reported as 5-year Kaplan-Meier rate estimates. Results All 16 baseline characteristics were balanced in the matched cohort of 140 patients with S-ICDs and 140 patients with TV-ICDs (median age 41 years interquartile range: 30 to 52 years and 40% women). The complication rate was 13.7% in the S-ICD group versus 18.0% in the TV-ICD group (p = 0.80). The infection rate was 4.1% versus 3.6% in the TV-ICD groups (p = 0.36). Lead complications were lower in the S-ICD arm compared with the TV-ICD arm, 0.8% versus 11.5%, respectively (p = 0.03). S-ICD patients had more nonlead-related complications than TV-ICD patients, 9.9% versus 2.2%, respectively (p = 0.047). Appropriate ICD intervention (antitachycardia pacing and shocks) occurred more often in the TV-ICD group (hazard ratio HR: 2.42; p = 0.01). The incidence of appropriate (TV-ICD HR: 1.46; p = 0.36) and inappropriate shocks (TV-ICD HR: 0.85; p = 0.64) was similar. Conclusions The complication rate in patients implanted with an S-ICD or TV-ICD was similar, but their nature differed. The S-ICD reduced lead-related complications significantly, at the cost of nonlead-related complications. Rates of appropriate and inappropriate shocks were similar between the 2 groups.
A leadless intracardiac transcatheter pacing system has been designed to avoid the need for a pacemaker pocket and transvenous lead.
In a prospective multicenter study without controls, a ...transcatheter pacemaker was implanted in patients who had guideline-based indications for ventricular pacing. The analysis of the primary end points began when 300 patients reached 6 months of follow-up. The primary safety end point was freedom from system-related or procedure-related major complications. The primary efficacy end point was the percentage of patients with low and stable pacing capture thresholds at 6 months (≤2.0 V at a pulse width of 0.24 msec and an increase of ≤1.5 V from the time of implantation). The safety and efficacy end points were evaluated against performance goals (based on historical data) of 83% and 80%, respectively. We also performed a post hoc analysis in which the rates of major complications were compared with those in a control cohort of 2667 patients with transvenous pacemakers from six previously published studies.
The device was successfully implanted in 719 of 725 patients (99.2%). The Kaplan-Meier estimate of the rate of the primary safety end point was 96.0% (95% confidence interval CI, 93.9 to 97.3; P<0.001 for the comparison with the safety performance goal of 83%); there were 28 major complications in 25 of 725 patients, and no dislodgements. The rate of the primary efficacy end point was 98.3% (95% CI, 96.1 to 99.5; P<0.001 for the comparison with the efficacy performance goal of 80%) among 292 of 297 patients with paired 6-month data. Although there were 28 major complications in 25 patients, patients with transcatheter pacemakers had significantly fewer major complications than did the control patients (hazard ratio, 0.49; 95% CI, 0.33 to 0.75; P=0.001).
In this historical comparison study, the transcatheter pacemaker met the prespecified safety and efficacy goals; it had a safety profile similar to that of a transvenous system while providing low and stable pacing thresholds. (Funded by Medtronic; Micra Transcatheter Pacing Study ClinicalTrials.gov number, NCT02004873.).
Three incisions in the chest are necessary for implantation of the entirely subcutaneous implantable cardioverter-defibrillator (S-ICD). The superior parasternal incision is a possible risk for ...infection and a potential source of discomfort. A less invasive alternative technique of implanting the S-ICD electrode--the two-incision technique--avoids the superior parasternal incision.
The purpose of this prospective cohort study was to evaluate the safety and efficacy of the two-incision technique for implantation of the S-ICD.
Consecutive patients who received an S-ICD between October 2010 and December 2011 were implanted using the two-incision technique, which positions the parasternal part of the S-ICD electrode using a standard 11Fr peel-away sheath. All patients were routinely evaluated for at least 1 year for complications and device interrogation at the outpatient clinic.
Thirty-nine patients (46% male, mean age 44 ± 15 years) were implanted with a S-ICD using the two-incision technique. During mean follow-up of 18 months (range 14-27 months) no dislocations were observed, and there was no need for repositioning of either the ICD or the electrode. No serious infections occurred during follow-up except for 2 superficial wound infections of the pocket incision site. Device function was normal in all patients, and no inappropriate sensing occurred related to the implantation technique.
The two-incision technique is a safe and efficacious alternative for S-ICD implantations and may help to reduce complications. The two-incision technique offers physicians a less invasive and simplified implantation procedure of the S-ICD.
Permanent cardiac pacing is the only effective treatment for symptomatic bradycardia, but complications associated with conventional transvenous pacing systems are commonly related to the pacing lead ...and pocket. We describe the early performance of a novel self-contained miniaturized pacemaker.
Patients having Class I or II indication for VVI pacing underwent implantation of a Micra transcatheter pacing system, from the femoral vein and fixated in the right ventricle using four protractible nitinol tines. Prespecified objectives were >85% freedom from unanticipated serious adverse device events (safety) and <2 V 3-month mean pacing capture threshold at 0.24 ms pulse width (efficacy). Patients were implanted (n = 140) from 23 centres in 11 countries (61% male, age 77.0 ± 10.2 years) for atrioventricular block (66%) or sinus node dysfunction (29%) indications. During mean follow-up of 1.9 ± 1.8 months, the safety endpoint was met with no unanticipated serious adverse device events. Thirty adverse events related to the system or procedure occurred, mostly due to transient dysrhythmias or femoral access complications. One pericardial effusion without tamponade occurred after 18 device deployments. In 60 patients followed to 3 months, mean pacing threshold was 0.51 ± 0.22 V, and no threshold was ≥2 V, meeting the efficacy endpoint (P < 0.001). Average R-wave was 16.1 ± 5.2 mV and impedance was 650.7 ± 130 ohms.
Early assessment shows the transcatheter pacemaker can safely and effectively be applied. Long-term safety and benefit of the pacemaker will further be evaluated in the trial.
ClinicalTrials.gov ID NCT02004873.
The subcutaneous implantable-cardioverter defibrillator (S-ICD) and leadless cardiac pacemaker (LCP) were designed to eliminate the need for transvenous leads, and initial studies have shown safety ...and efficacy for both devices (2-4). The combined LCP and S-ICD therapy that was studied is a proof of concept of successful wireless device-device communication in cardiac rhythm management and a first step toward establishing multicomponent device systems that eliminate transvenous leads.
A Dual-Chamber Leadless Pacemaker Knops, Reinoud E; Reddy, Vivek Y; Ip, James E ...
The New England journal of medicine,
06/2023, Letnik:
388, Številka:
25
Journal Article
Recenzirano
Single-chamber ventricular leadless pacemakers do not support atrial pacing or consistent atrioventricular synchrony. A dual-chamber leadless pacemaker system consisting of two devices implanted ...percutaneously, one in the right atrium and one in the right ventricle, would make leadless pacemaker therapy a treatment option for a wider range of indications.
We conducted a prospective, multicenter, single-group study to evaluate the safety and performance of a dual-chamber leadless pacemaker system. Patients with a conventional indication for dual-chamber pacing were eligible for participation. The primary safety end point was freedom from complications (i.e., device- or procedure-related serious adverse events) at 90 days. The first primary performance end point was a combination of adequate atrial capture threshold and sensing amplitude at 3 months. The second primary performance end point was at least 70% atrioventricular synchrony at 3 months while the patient was sitting.
Among the 300 patients enrolled, 190 (63.3%) had sinus-node dysfunction and 100 (33.3%) had atrioventricular block as the primary pacing indication. The implantation procedure was successful (i.e., two functioning leadless pacemakers were implanted and had established implant-to-implant communication) in 295 patients (98.3%). A total of 35 device- or procedure-related serious adverse events occurred in 29 patients. The primary safety end point was met in 271 patients (90.3%; 95% confidence interval CI, 87.0 to 93.7), which exceeded the performance goal of 78% (P<0.001). The first primary performance end point was met in 90.2% of the patients (95% CI, 86.8 to 93.6), which exceeded the performance goal of 82.5% (P<0.001). The mean (±SD) atrial capture threshold was 0.82±0.70 V, and the mean P-wave amplitude was 3.58±1.88 mV. Of the 21 patients (7%) with a P-wave amplitude of less than 1.0 mV, none required device revision for inadequate sensing. At least 70% atrioventricular synchrony was achieved in 97.3% of the patients (95% CI, 95.4 to 99.3), which exceeded the performance goal of 83% (P<0.001).
The dual-chamber leadless pacemaker system met the primary safety end point and provided atrial pacing and reliable atrioventricular synchrony for 3 months after implantation. (Funded by Abbott Medical; Aveir DR i2i ClinicalTrials.gov number, NCT05252702.).
Endocardial pacemaker leads and right ventricular (RV) pacing are well-known causes of tricuspid valve, mitral valve, and cardiac dysfunction. Lead-related adverse consequences can potentially be ...mitigated by leadless pacemaker (LP) therapy by eliminating the presence of a transvalvular lead. This study assessed the impact of LP placement on cardiac and valvular structure and function.
Echocardiographic studies before and 12±1 months after LP implantation were performed between January 2013 and May 2018 at our center and compared with age- and sex-matched controls of dual-chamber transvenous pacemaker recipients.
A total of 53 patients receiving an LP were included, of whom 28 were implanted with a Nanostim and 25 with a Micra LP device. Tricuspid valve regurgitation was graded as being more severe in 23 (43%) patients at 12±1 months compared with baseline ( P<0.001). Compared with an apical position, an RV septal position of the LP was associated with increased tricuspid valve incompetence (odds ratio, 5.20; P=0.03). An increase in mitral valve regurgitation was observed in 38% of patients ( P=0.006). LP implantation resulted in a reduction of RV function, according to a lower tricuspid annular plane systolic excursion ( P=0.003) and RV tricuspid lateral annular systolic velocity ( P=0.02), and a higher RV Tei index ( P=0.04). LP implantation was further associated with a reduction of left ventricular ejection fraction ( P=0.03) and elevated left ventricular Tei index ( P=0.003). The changes in tricuspid valve regurgitation in the LP group were similar to the changes in the dual-chamber transvenous pacemaker control group (43% versus 38%, respectively; P=0.39).
LP therapy is associated with an increase in tricuspid valve dysfunction through 12 months of follow-up; yet it was comparable to dual-chamber transvenous pacemaker systems. Furthermore, LP therapy seems to adversely impact mitral valve and biventricular function.
Most inappropriate shocks from the subcutaneous implantable cardioverter-defibrillator (S-ICD) are caused by cardiac oversensing. A novel sensing methodology, SMART Pass (SP; Boston Scientific ...Corporation, Natick, MA), aims to reduce cardiac oversensing.
The purpose of this study was to evaluate the effect of SP on shocks in ambulatory patients with S-ICD.
Patients implanted in 2015–2016 and enrolled in a remote patient monitoring system were included and followed for 1 year. Shocks were adjudicated by 3 independent blinded reviewers as appropriate or inappropriate. Shock incidence was calculated for patients with SP programmed enabled or disabled at implantation, censoring patients when SP programming changed or at the last transmission. The SP setting (enabled vs disabled) was modeled as a time-dependent Cox regression variable.
The cohort consisted of 1984 patients, and a total of 880 shocks were adjudicated. At implantation, SP was enabled in 655 patients (33%) and disabled in 1329 patients (67%). SP reduced the risk for the first inappropriate shock by 50% (P < .001) and the risk for all inappropriate shocks by 68% (P < .001) in multivariate analysis adjusted for age and device programming. The incidence of inappropriate shocks was 4.3% in the SP enabled arm vs 9.7% in the SP disabled arm. The incidence of appropriate shocks was similar (5.2% vs 6.6%; P = .18) along with the time to treat the first appropriate shock (17.4 seconds vs 16.7 seconds; P = .92) for SP enabled vs disabled, respectively.
This prospective blinded evaluation of the SP filter demonstrates that enabling the SP filter results in a significant reduction of inappropriate shocks by the S-ICD without a negative effect on appropriate shocks.
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