Fluoroscopic investigation of Riata® transvenous defibrillator leads

Background: Implantable cardioverter-defibrillator leads from Riata® family (St. Jude Medical Inc., Sylmar, CA, USA) have been recently recalled by Food and Drug Administration for concerns of a unique type of “inside-out” insulation failure leading to conductor externalization. The objective of this study was to evaluate the prevalence and predictors of conductor externalization in patients implanted with Riata 8 French (Fr) and 7 Fr leads. Methods: Patients implanted with Riata® and Riata ST® who were actively followed up in our institution were scheduled for high resolution 3 view fluoroscopy and device interrogation including high voltage (HV) lead impedance testing. Fluoroscopic images were graded as presence of externalization or no externalization. Results: Of the 90 patients who underwent screening fluoroscopy, majority had dual coil leads (62.5%) and median duration from the implant time to screening was 79.5 months. Twenty four (26.7%) patients exhibited evidence of lead externalization with 10 (41.6%) of these showing electrical abnormalities at the time of screening. No externalization was seen in the 7 Fr leads. Pacing thresholds were significantly elevated in the externalized cohort compared to non-externalized group (1.42 ± 1.23 vs. 0.93 ± 0.53; p = 0.01). Time since lead implant and lead diameter emerged as significant predictors of lead externalization on univariate analysis with only lead diameter being significant on multivariate analysis (odds ratio 30.68; 4.95–∞, p = 0.001). Conclusions: Prevalence of insulation failure exhibiting as conductor externalization is high (26.7%) among the large diameter 8 Fr Riata® leads with a significant proportion of patients manifesting electrical failure. High resolution 3 view fluoroscopy is a reasonable approach to screen for this unique type of insulation failure

Device Therapies Among Patients Receiving Primary Prevention Implantable Cardioverterâ Defibrillators in the Cardiovascular Research Network

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143721/1/jah33061_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143721/2/jah33061.pd

Design and characteristics of the prophylactic intra-operative ventricular arrhythmia ablation in high-risk LVAD candidates (PIVATAL) trial

BACKGROUND: The use of a Left Ventricular Assist Device (LVAD) in patients with advanced heart failure refractory to optimal medical management has progressed steadily over the past two decades. Data have demonstrated reduced LVAD efficacy, worse clinical outcome, and higher mortality for patients who experience significant ventricular tachyarrhythmia (VTA). We hypothesize that a novel prophylactic intra-operative VTA ablation protocol at the time of LVAD implantation may reduce the recurrent VTA and adverse events postimplant. METHODS: We designed a prospective, multicenter, open-label, randomized-controlled clinical trial enrolling 100 patients who are LVAD candidates with a history of VTA in the previous 5 years. Enrolled patients will be randomized in a 1:1 fashion to intra-operative VTA ablation (n = 50) versus conventional medical management (n = 50) with LVAD implant. Arrhythmia outcomes data will be captured by an implantable cardioverter defibrillator (ICD) to monitor VTA events, with a uniform ICD programming protocol. Patients will be followed prospectively over a mean of 18 months (with a minimum of 9 months) after LVAD implantation to evaluate recurrent VTA, adverse events, and procedural outcomes. Secondary endpoints include right heart function/hemodynamics, healthcare utilization, and quality of life. CONCLUSION: The primary aim of this first-ever randomized trial is to assess the efficacy of intra-operative ablation during LVAD surgery in reducing VTA recurrence and improving clinical outcomes for patients with a history of VTA

Assessment of primary prevention patients receiving an ICD - Systematic evaluation of ATP: APPRAISE ATP

Background: The value of antitachycardia pacing (ATP) in the overall cohort of primary prevention patients who receive implantable cardioverter-defibrillators (ICDs) remains uncertain. ATP success reported in prior trials potentially included a large number of patients receiving unnecessary ATP for arrhythmias that may have self-terminated owing to the prematurity of the intervention. Although some patients derive benefit from initial ATP in terminating rapid ventricular arrhythmias and thereby preventing shocks, there are limited data allowing us to identify those patients Objective: The purpose of APPRAISE ATP is to understand the role of ATP in primary prevention patients currently indicated for ICD therapy in a large prospective randomized controlled trial with modern programming parameters. Methods: The study is a global, prospective, randomized, multicenter clinical trial conducted at up to 150 sites globally, enrolling approximately 2600 subjects The primary endpoint of the trial is time to first all-cause shock in a 2-arm study with an equivalent study design in which the incidence of all-cause shocks will be compared between primary prevention subjects programmed with shocks only vs subjects programmed to standard therapy (ATP and shock). Results: An Electrogram and Device Interrogation Core Laboratory will review interrogation data to determine primary endpoints that occur in APPRAISE ATP. Their decisions are based on independent physician review of the data from device interrogation. Conclusion: The ultimate purpose of the study is to aid clinicians in the selection of ICD technologies based on hard endpoint evidence across the spectrum of indications for primary prevention implantation

Infection Predictors and Outcomes in Subcutaneous Implantable Cardioverter Defibrillator Patients

Background: Recent studies in the US have shown that the subcutaneous implantable cardioverter defibrillator (S-ICD) is being used in populations with more co-morbidities and at higher risk for infection. Previous studies of infection in the S-ICD have evaluated short term follow-up and healthier patients. Objective: To determine the incidence and predictors of S-ICD-related infection in patients (pts) enrolled in the S-ICD Post-Approval Study (PAS). Methods: The S-ICD PAS is a US prospective registry of 1637 pts across 86 sites. Baseline demographics and outcomes with 1-year post-implant follow-up were compared between pts with and without device-related infection requiring surgical intervention. Multivariate logistic regression analysis was performed to determine infection predictors. Results: Infection was observed in 2.7% of pts. No pt had lead extraction complications or bacteremia related to the device. Baseline demographics and procedure data are compared in the Table between pts with and without infection. Predictors of infection were longer procedure time (p=0.0492), being diabetic (p=0.0091), having a prior defibrillator implant (p\u3c0.0001), and the presence of hematoma post-implant (p=0.0032). In contrast to reports of transvenous ICDs, dialysis was not predictive of S-ICD infection. Conclusion: In this more traditional ICD population, rates of infection were similar to other S-ICD populations and not associated with systemic blood-borne infections. Longer procedure time, diabetes, prior defibrillator implant, and initial development of a hematoma increased infection risk

Infection in patients with subcutaneous implantable cardioverter-defibrillator: Results of the S-ICD Post Approval Study

BACKGROUND: Early subcutaneous implantable cardioverter-defibrillator (S-ICD) studies included atypical cohorts of patients who were younger with fewer comorbidities. Recent S-ICD studies included patient populations with more comorbidities. OBJECTIVES: The goals of this study were to determine the incidence and predictors of S-ICD-related infection over a 3-year follow-up period and to use these results to develop an infection risk score. METHODS: The S-ICD Post Approval Study is a US prospective registry of 1637 patients. Baseline demographic characteristics and outcomes with 3-year postimplantation follow-up were compared between patients with and without device-related infection. A risk score was derived from multivariable proportional hazards analysis of 22 variables. RESULTS: Infection was observed in 55 patients (3.3%), with 69% of infections occurring within 90 days and a vast majority (92.7%) within 1 year of implantation. Late infections more likely involved device erosion; no infections occurred after year 2. The annual mortality rate postinfection was 0.6%/y. No lead extraction complications or bacteremia related to infection were observed. An infection risk score was created with diabetes, age, prior transvenous ICD implant, and ejection fraction as predictors. Patients with a risk score of ≥3 had an 8.8 hazard ratio (95% confidence interval 2.8-16.3) of infection compared with a 0 risk score. CONCLUSION: Infection rates in the S-ICD Post Approval Study were similar to other S-ICD populations and not associated with systemic blood-borne infections. Late infection (\u3e1 year) is uncommon and associated with system erosion. A high-risk infection cohort can be identified that may facilitate preventive measures. CLINCALTRIALS. GOV IDENTIFIER: NCT01736618

Multicenter automatic defibrillator implantation trial–subcutaneous implantable cardioverter defibrillator (madit s-icd): Design and clinical protocol

Patients with diabetes mellitus, prior myocardial infarction, older age, and a relatively preserved left ventricular ejection fraction remain at risk for sudden cardiac death that is potentially amenable by the subcutaneous implantable cardioverterdefibrillator with a good risk-benefit profile. The launched MADIT S-ICD study is designed to test the hypothesis that post–myocardial infarction diabetes patients with relatively preserved ejection fraction of 36%-50% will have a survival benefit from a subcutaneous implantable cardioverter defibrillator