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Defibrillation leads remain the Achilles heel of implantable cardioverter-defibrillators. As patients with implantable cardioverter-defibrillators are living longer and battery longevity increases, more durable leads are needed. The LEADR trial evaluated the novel, lumenless, small-diameter, OmniaSecure defibrillation lead and demonstrated favorable safety and efficacy profile as well as zero fractures through 12.7 ± 4.8 months and remains in clinical follow-up. To augment the clinical trial, advanced cardiac lead reliability modeling was used to project long-term lead durability. We aimed to project the 10-year fracture-free survival of the OmniaSecure defibrillation lead using reliability modeling. The validated reliability model, which incorporates patient and bench test data, was used to project the 10-year fracture-free survival of the OmniaSecure lead. A subset of LEADR trial patients underwent biplane fluoroscopy imaging during cardiac and patient motion to evaluate the lead's bending curvature in vivo. Bench tests then reproduced these use conditions with greater bending curvatures than observed in patients to exaggerate stress on the lead and to evaluate the lead fatigue strength. The reliability modeling projects a 98.2% fracture-free survival rate of the OmniaSecure lead at 10 years, including a 10-year fracture-free survival rate of 97.9% in adolescents, exceeding both the modeled and clinical 10-year performance of the highly reliable, larger diameter Sprint Quattro lead. Consistent with early clinical trial experience, modeling projects highly durable 10-year performance of the OmniaSecure lead, including within the active adolescent pediatric population, which may uniquely benefit from a novel 4.7F defibrillation lead designed for reliability. NCT04863664 [Display omitted] [ABSTRACT FROM AUTHOR]

The healing response to cardiac implantable electronic device (CIED) implantation results in inflammation that can lead to fibrous pocket formation, which may disrupt pocket healing or complicate future interventions. The purpose of this study was to assess CIED pocket healing with use of the second-generation TYRX absorbable antibacterial envelope (T2), the next-generation (NG) TYRX absorbable antibacterial envelope under development, and the CanGaroo® extracellular matrix envelope (ECM) compared to no envelope. A total of 110 CIEDs were implanted in an ovine model, either with (T2, NG, or ECM) or without envelopes. Histopathologic and morphometric analyses were completed at several timepoints after implant (3 days, 7 days, 4 weeks, 12 weeks, 24 weeks). An independent pathologist completed a blinded histopathology assessment of the pockets. TYRX (T2/NG) pockets showed similar inflammatory and healing profiles to controls with more rapid provisional matrix formation compared to controls and ECM. ECM pockets exhibited increased acute (3 and 7 days) and chronic (24 weeks) inflammation. T2/NG had almost complete (T2) or complete (NG) absorption by week 12. ECM remained present at week 24 and was associated with significantly thicker capsules (ECM 0.80 ± 0.14 mm; NG 0.37 ± 0.10 mm; control 0.56 ± 0.17 mm). Compared to ECM, pockets with TYRX showed less inflammation, more rapid provisional matrix formation, faster absorption, and thinner capsules. TYRX pockets had low inflammation comparable to controls with accelerated provisional matrix deposition and tissue adhesion. The healing response to CIEDs used with TYRX fosters the formation of a well-healed pocket, which may bring patient benefit beyond its proven infection reduction. [Display omitted] [ABSTRACT FROM AUTHOR]

Transcatheter aortic valve replacement (TAVR) is well established for treating severe symptomatic aortic stenosis. Whereas broad information on the epidemiology, clinical implications, and management of bradyarrhythmias after TAVR is available, data about tachyarrhythmic events remain scarce. Despite the progressively lower risk profile of TAVR patients and the improvement in device characteristics and operator skills, approximately 10% of patients develop new-onset atrial fibrillation (NOAF) after TAVR. The proportion of patients in whom NOAF actually corresponds to previously undiagnosed silent atrial fibrillation (AF) has not been properly determined. The transapical approach, the need for pre- or post- balloon dilation, and the presence of periprocedural complications have been associated with a higher risk of NOAF. Older age, left atrial volume, or worse functional class are patient-derived risk factors shared with preprocedural AF. NOAF after TAVR has been associated with poorer survival and a higher incidence of cerebrovascular events. However, patient management differs markedly among different centers, especially with regard to anticoagulation in patients with short-duration AF episodes detected in the periprocedural setting and in cases of silent NOAF detected during continuous electrocardiographic (ECG) monitoring. Evidence about ventricular arrhythmias is even more scarce than for AF. Some case reports of sudden cardiac death after TAVR in patients with a pacemaker have identified ventricular tachycardia or ventricular fibrillation in device interrogation. TAVR has been shown to reduce the arrhythmic burden, but a significant proportion of patients (16%) present with complex premature ventricular complex arrhythmias within the year after TAVR. Whether these events are related to poorer outcomes is unknown. Continuous ECG monitoring after TAVR may help describe the frequency, risk factors, and prognostic implications of tachyarrhythmias in this population. [ABSTRACT FROM AUTHOR]

Background: Transvenous lead extraction can have serious adverse events, such as cardiac or vascular perforation. Risk factors have not been well characterized.Objective: The purpose of this study was to identify factors associated with perforation and death, and to characterize lead extraction in a large contemporary population.Methods: We performed a retrospective multicenter study examining patients undergoing lead extraction at 8 Canadian institutions from 1996 through 2016. Demographic and clinical data were used to identify variables associated with perforation and mortality using logistic regression modeling.Results: A total of 2325 consecutive patients (age 61.9 ±16.5 years) underwent extraction of 4527 leads. Perforation rate was 2.7% (63/2325) and 30-day mortality was 1.6% (38/2325), with mortality of 0.4% due to perforation (10/2325). Variables associated with perforation included no previous cardiac surgery (odds ratio [OR] 3.33; 95% confidence interval [CI] 1.54-7.19; P = .002), female sex (OR 3.27; 95% CI 1.91-5.60; P <.001); left ventricular ejection fraction ≥40% (OR 2.81; 95% CI 1.28-6.14; P = .010); lead age >8 years (OR 2.64; 95% CI 1.52-4.60; P <.001); ≥2 leads extracted (OR 2.49; 95% CI 1.23-5.04; P = .011); and diabetes (OR 2.12; 95% CI 1.16-3.86; P = .014). Variables associated with death included infection as indication for extraction (OR 3.85; 95% CI 1.38-10.73; P = .010); anemia (OR 3.14; 95% CI 1.38-6.61; P = .003), and patient age (OR 1.04; 95% CI 1.01-1.07; P = .012).Conclusion: Risk factors associated with perforation in lead extraction include no history of cardiac surgery, female sex, preserved left ventricular ejection fraction, lead age >8 years, ≥2 leads extracted, and diabetes. [ABSTRACT FROM AUTHOR]

Background: Hematoma is a complication of cardiac implantable electronic device (CIED) procedures and may lead to device infection. The TYRX antibacterial envelope reduced major CIED infection by 40% in the randomized WRAP-IT (World-wide Randomized Antibiotic Envelope Infection Prevention Trial) study, but its effectiveness in the presence of hematoma is not well understood.Objective: The purpose of this study was to evaluate the incidence and infectious consequences of hematoma and the association between envelope use, hematomas, and major CIED infection among WRAP-IT patients.Methods: All 6800 study patients were included in this analysis (control 3429; envelope 3371). Hematomas occurring within 30 days postprocedure (acute) were characterized and grouped by study treatment and evaluated for subsequent infection risk. Data were analyzed using Cox proportional hazard regression modeling.Results: Acute hematoma incidence was 2.2% at 30 days, with no significant difference between treatment groups (envelope vs control hazard ratio [HR] 1.15; 95% confidence interval [CI] 0.84-1.58; P = .39). Through all follow-up, the risk of major infection was significantly higher among control patients with hematoma vs those without (13.1% vs 1.6%; HR 11.3; 95% CI 5.5-23.2; P <.001). The risk of major infection was significantly lower in the envelope vs control patients with hematoma (2.5% vs 13.1%; HR 0.18; 95% CI 0.04-0.85; P = .03).Conclusion: The risk of hematoma was 2.2% among WRAP-IT patients. Among control patients, hematoma carried a >11-fold risk of developing a major CIED infection. This risk was significantly mitigated with antibacterial envelope use, with an 82% reduction in major CIED infection among envelope patients who developed hematoma compared to control. [ABSTRACT FROM AUTHOR]

Background: Cardiac device procedures require tissue dissection to free existing device lead(s). Common techniques include blunt dissection, standard electrocautery, and low-temperature electrocautery (PlasmaBlade, Medtronic); however, data on the type of electrosurgical tool used and the development of procedure- or lead-related adverse events are limited.Objective: The purpose of this study was to determine whether standard or low-temperature electrocautery impacts the development of an adverse event.Methods: We evaluated patients enrolled in WRAP-IT (Worldwide Randomized Antibiotic EnveloPe Infection PrevenTion Trial) undergoing cardiac implantable electronic device (CIED) revision, upgrade, or replacement. All adverse events were adjudicated by an independent physician committee. Data were analyzed using Cox proportional hazard regression modeling.Results: In total, 5641 patients underwent device revision/upgrade/replacement. Electrocautery was used in 5205 patients (92.3%) (mean age 70.6 ± 12.7 years; 28.8% female), and low-temperature electrocautery was used in 1866 patients (35.9%). Compared to standard electrocautery, low-temperature electrocautery was associated with a 23% reduction in the incidence of a procedure- or lead-related adverse event through 3 years of follow up (hazard ratio [HR] 0.77; 95% confidence interval [CI] 0.65-0.91; P = .002). After controlling for the number of active leads, degree of capsulectomy, degree of lead dissection, and renal dysfunction, low-temperature electrocautery was associated with a 32% lower risk of lead-related adverse events (HR 0.68; 95% CI 0.52-0.89; P = .004). These effects were consistent across a spectrum of lead-related adverse event types.Conclusion: This study represents one of the largest assessments of electrocautery use in patients undergoing CIED revision, upgrade, or replacement procedures. Compared to standard electrocautery, low-temperature electrocautery significantly reduces adverse effects from these procedures. [ABSTRACT FROM AUTHOR]

Background: The Riata lead advisory was announced in 2011 and has posed unique management challenges because of cable externalization and insulation abrasion, in some cases leading to sudden loss of defibrillation.Objective: The purpose of this study was to provide further data on the rate of electrical failure in a population of patients with a Riata lead under advisory.Methods: Using the Canadian Registry of Electronic Device Outcomes, prospective follow-up data were collected on 1352 Riata leads under advisory in 17 implantable cardioverter-defibrillator (ICD) implantation centers in Canada. Data on electrical and structural failure were collected, as well as periprocedural complications related to lead revision (abandonment or extraction).Results: Of the 1352 leads included in this 12-month follow-up cohort, 110 leads were revised. Mean follow-up time was 10.4 ± 1.5 years. The 12-year rate of electrical failure for the 8Fr lead was 9.45%, whereas the 10-year failure rate for the 7Fr lead was 7.25% and was not found to be accelerating. Of the leads revised because of advisory only (patient preference, advisory related, electrical or structural failure), the majority were abandoned (n = 54 [76.0%]), whereas 17 (24.0%) were extracted using power tools. The rate of major complications in each group was 5.6% and 5.9%, respectively.Conclusion: This report provides further data on the risk of electrical lead failure over a long lead dwell time. The risk of failure exceeds the risk of periprocedural major complications, indicating that the risk-to-benefit ratio is favorable to revise the lead in appropriate clinical scenarios. [ABSTRACT FROM AUTHOR]

Objectives This study sought to describe the 1-year experience with the transcatheter FORMA system for severe tricuspid regurgitation (TR). Background Severe TR is associated with significant morbidity and mortality. Novel transcatheter therapies have been recently developed. Methods Eighteen patients underwent device implantation at 3 centers in Canada and Switzerland. Baseline characteristics, procedural, 30-day, and 1-year outcomes were prospectively evaluated using multimodality imaging and hemodynamic and clinical assessments. Results Procedural success was achieved in 16 (89%) patients. Unsuccessful procedures were because of right ventricular perforation requiring open surgery and device dislocation. At 1 year there were no deaths, significant arrhythmias, device infections, or dislocations. Thrombus was observed on 1 device at 4 months and there was 1 rehospitalization for heart failure. Among the 14 patients with successful device implantation and 1-year follow-up, 79% were in New York Heart Association functional class I/II (p < 0.001), the average 6-min walk test increased by 84 m (p = 0.03), and the Kansas City Cardiomyopathy Questionnaire heart failure score improved by 18 points (p = 0.02) compared with baseline. Echocardiography showed a reduction of TR from severe in 17 of 18 (94%) patients at baseline to moderate-severe or less in 11 of 16 patients (69%) by 30 days (p = 0.001) and 6 of 13 patients (46%) by 1 year (p = 0.01). The diameters of the tricuspid annulus and the right ventricle were reduced at 1 year (45.7 ± 4.8 mm to 42.1 ± 4.4 mm, p = 0.004; 54 ± 5.3 mm to 49.9 ± 4.3 mm, p = 0.02, respectively). Conclusions Implantation of the FORMA system in high-risk patients with severe TR shows feasibility with a good mid-term safety profile. At 1 year, despite variable success in reducing echocardiographic TR grade, there were significant clinical improvements and reductions in right ventricular dimensions. [ABSTRACT FROM AUTHOR]

Background: Patients who require perioperative anticoagulation during cardiac implantable electronic device surgery are at increased risk for bleeding complications. The BRUISE CONTROL trial demonstrated that continuing warfarin was safer than heparin bridging, reducing the incidence of clinically significant pocket hematoma. Novel oral anticoagulants are being increasingly prescribed in place of warfarin. The best perioperative management of these new anticoagulants is unknown.Methods/design: A randomized controlled trial to investigate whether a strategy of continued vs interrupted novel oral anticoagulant (dabigatran, rivaroxaban, or apixaban) at the time of device surgery, in patients with moderate to high risk of arterial thromboembolic events, reduces the incidence of clinically significant hematoma (defined as a hematoma requiring reoperation and/or resulting in prolongation of hospitalization, and/or requiring interruption of anticoagulation). The secondary outcomes include components of the primary outcome, composite of all other major perioperative bleeding events, thromboembolic events, all-cause mortality, cost-effectiveness, patient quality of life, perioperative pain, and satisfaction. Planned analyses include descriptive statistics of all baseline variables. For the primary outcome, interrupted vs continued novel oral anticoagulant arms will be compared using the χ(2) test. If any clinically significant differences are identified, a logistic regression analysis will be conducted. Quality of life will be assessed using EuroQol-5D, and perioperative pain using a visual analog scale.Discussion: BRUISE CONTROL-2 is a randomized trial evaluating the best strategy to manage novel oral anticoagulants at the time of device surgery. We hypothesize that device surgery can be performed safely without interruption of these medications. [ABSTRACT FROM AUTHOR]

Background: The St. Jude Medical Riata family of implantable cardioverter-defibrillator (ICD) leads has demonstrated a high rate of externalized conductors and electrical failure. Objective: Given similar design elements of Durata to Riata, the purpose of this study was to assess the rates of failure of the Riata ST Optim and Durata lead families in Canada. Methods: All Canadian ICD-implanting centers were invited to submit follow-up information on all Optim-coated ICD leads implanted. Electrical failure was defined as a rapid change in impedance or pacing capture threshold leading to lead revision, or oversensing due to noise. Externalized conductors were defined as appearance of conductor wires outside the lead body. Systematic fluoroscopic screening for externalized conductors was not performed. Results: As of December 1, 2012, 15 of 25 centers provided data on 3981 leads (44% of those sold in Canada during the same timeframe): 3477 Durata and 504 Riata ST Optim leads. The most common model numbers were 7122 (1516 leads [38%]), 7121 (707 leads [18%]), and 7120 (622 leads [16%]). Mean follow-up duration from implant to December 1, 2012, was 4.47 ± 0.48 years for Riata ST Optim leads and 2.00 ± 1.10 years for Durata leads. The annual rate of lead failure was 0.27% per year for Riata ST Optim leads and 0.24% per year for Durata leads. No instances of externalized conductors were identified in the failed leads. No deaths were attributed to lead failure; however, 2 patients experienced inappropriate shocks due to lead failure. Conclusion: The overall electrical failure rates of the Riata ST Optim and Durata leads appear to be low, and no instances of externalized conductors were observed. [Copyright &y& Elsevier]

Background: Defibrillation threshold (DFT) testing has traditionally been a routine part of implantable cardioverter-defibrillator (ICD) implantation, despite a lack of compelling evidence that it predicts or improves outcomes. In the past, when devices were much less reliable, DFT testing seemed prudent; however, modern ICD systems have such a high rate of successful defibrillation that many electrophysiologists now question whether DFT testing is still worthwhile, particularly since DFT testing may now be the highest acute risk component of ICD implantation. Objective: The purpose of this study was to systematically document complications directly attributable to intraoperative DFT testing. Methods: We obtained data on DFT-related complications from all 21 adult ICD implant centers in Canada, covering the period from January 1, 2000, to September 30, 2006. Results: There were a total of 19,067 ICD implants in Canada during the study period. There were three DFT testing–related deaths, five DFT testing–related strokes, and 27 episodes that required prolonged resuscitation. Two patients had significant clinical sequelae after prolonged resuscitation. Conclusions: The risk of severe complications from intraoperative DFT testing appears small, even allowing for the underestimation of its true rate with the current study methodology. These slight but measurable risks must be considered when assessing the risk-benefit ratio of the procedure. Additional data from ongoing prospective ICD registries and/or clinical trials are required. [Copyright &y& Elsevier]

INSIGHTS FROM THE WRAP-IT TRIAL. HEMATOMA AND CARDIAC IMPLANTABLE ELECTRONIC DEVICE INFECTION. [Extracted from the article]

Studies the circadian variation of paroxysmal atrial fibrillation (AF). Study methods and patients; Time of onset, total duration of AF episodes; Presence of a circadian variation of AF with a distinct bimodal distribution.