The role of early cardiac resynchronization therapy implantation in dilated cardiomyopathy patients with narrow QRS carrying lamin A/C mutation.

BACKGROUND: Dilated cardiomyopathy (DCM) caused by Lamin A/C gene (LMNA) mutation is complicated with atrioventricular conduction disturbances, malignant ventricular arrhythmias and progressive severe heart failure. OBJECTIVE: We hypothesized that early cardiac resynchronization therapy (CRT) implantation in LMNA mutation carriers with an established indication for pacemaker or implantable cardioverter defibrillator (ICD), may preserve ejection fraction, and delay disease progression to end stage heart failure. METHODS: We compared the primary outcomes: time to heart transplantation, death due to end stage heart failure or ventricular tachycardia (VT) ablation and secondary outcomes: change in left ventricular ejection fraction (EF) and ventricular arrhythmia burden between LMNA DCM patients in the early CRT and non-CRT groups. RESULTS: Of ten LMNA DCM patients (age 51±10 years, QRS 96±14 msec, EF 55±7%) with indication for pacemaker or ICD implantation, five underwent early CRT-D implantation. After 7.2±4 years, three patients (60%) in the non-CRT group reached the primary outcome, compared to no patients in the CRT group (P=0.046). Four patients in non-CRT group (80%) experienced sustained ventricular tachycardia or received appropriate ICD shock compared to 1 patient (20%) in the CRT group (P=0.058). LMNA patients without early CRT had a higher burden of VPC/24 h in 12-lead holter (median 2352 vs 185, P=0.09). Echocardiography showed statistically lower LVEF in the non-CRT group compared to CRT group [(32±15)% vs (61±4)%, 95% CI: 32.97-61.03, P=0.016]. CONCLUSION: Early CRT implantation in LMNA cardiomyopathy patients, with an indication for pacemaker or ICD, may reduce heart failure deterioration and life-threatening heart failure complications.

The role of genetic testing in the prevention, diagnosis, and prognosis of sudden cardiac arrest in children.

Background: Determining the pathogenesis of sudden cardiac arrest (SCA) in children is crucial for its management and prognosis. Our aim is to analyze the role of broad genetic testing in the prevention, diagnosis, and prognosis of SCA in Children. Methods: ECG, 12-lead holter, exercise testing, cardiac imaging, familial study, and genetic testing were used to study 29 families, in whom a child experienced SCA. Results: After a thorough clinical and genetic evaluation a positive diagnosis was reached in 24/29 (83%) families. Inherited channelopathies (long QT syndrome and catecholaminergic polymorphic ventricular tachycardia) were the most prevalent 20/29 (69%) diagnosis, followed by cardiomyopathy 3/29 (10%). Broad genetic testing was positive in 17/24 (71%) cases. Using the Mann-Whitney test, we found that genetic testing (effect size = 0.625, p = 0.003), ECG (effect size = 0.61, p = 0.009), and exercise test (effect size = 0.63, p = 0.047) had the highest yield in reaching the final diagnosis. Genetic testing was the only positive test available for five (17%) families. Among 155 family members evaluated through cascade screening, 73 (47%) had a positive clinical evaluation and 64 (41%) carried a pathologic mutation. During 6 ± 4.8 years of follow-up, 58% of the survived children experienced an arrhythmic event. Of nine family members who had an ICD implant for primary prevention, four experienced appropriate ICD shock. Conclusions: The major causes of SCA among children are genetic etiology, and genetic testing has a high yield. Family screening has an additional role in both the diagnosis and preventing of SCA.

Elevated thrombin generation levels in the left atrial appendage in patients with atrial fibrillation.

Background: Atrial Fibrillation (AF) is the most common sustained tachi-arrhythmia. Thrombus formation in the left atrial appendage (LAA) increases the risk of stroke and systemic embolism in patients with AF. Objectives: The aim of this study was to compare thrombin generation in the LAA to the LA among patients with AF. Methods: A cross-sectional study of consecutive patients with AF undergoing pulmonary veins catheter ablation. Blood samples from the femoral vein (FV), right atrium (RA), left atrium (LA), and LAA were collected during the catheter ablation procedures. Thrombin generation was assessed by a Calibrated Automated Thrombogram. The LAA-calibrated automated thrombogram parameters were compared with the RA, LA, and FV. Results: A total of 47 consecutive patients were enrolled in the study. The endogenous thrombin potential and peak height were significantly higher in the LAA compared with the LA, the mean differences and 95% CI between the LA and LAA were -378.9 (-680.5, -77.2) (nM∗min) and -66.7 (-119.6, -13.8) (nM) in the endogenous thrombin potential and peak height respectively. Conclusion: In patients with AF undergoing catheter ablation, the LAA demonstrated increased thrombin generation compared with the LA. This finding might contribute to the understanding of why the LAA is more predisposed to thrombus formation than the LA. Clinical Trials Registration: NCT03795883.

Generalizable and robust deep learning algorithm for atrial fibrillation diagnosis across geography, ages and sexes.

To drive health innovation that meets the needs of all and democratize healthcare, there is a need to assess the generalization performance of deep learning (DL) algorithms across various distribution shifts to ensure that these algorithms are robust. This retrospective study is, to the best of our knowledge, an original attempt to develop and assess the generalization performance of a DL model for AF events detection from long term beat-to-beat intervals across geography, ages and sexes. The new recurrent DL model, denoted ArNet2, is developed on a large retrospective dataset of 2,147 patients totaling 51,386 h obtained from continuous electrocardiogram (ECG). The model's generalization is evaluated on manually annotated test sets from four centers (USA, Israel, Japan and China) totaling 402 patients. The model is further validated on a retrospective dataset of 1,825 consecutives Holter recordings from Israel. The model outperforms benchmark state-of-the-art models and generalized well across geography, ages and sexes. For the task of event detection ArNet2 performance was higher for female than male, higher for young adults (less than 61 years old) than other age groups and across geography. Finally, ArNet2 shows better performance for the test sets from the USA and China. The main finding explaining these variations is an impairment in performance in groups with a higher prevalence of atrial flutter (AFL). Our findings on the relative performance of ArNet2 across groups may have clinical implications on the choice of the preferred AF examination method to use relative to the group of interest.

Non-ischemic sudden cardiac arrest: Role of 12 lead Holter, family screening and genetic testing.

OBJECTIVE AND BACKGROUND: To evaluate the diagnostic and prognostic yield of a comprehensive protocol involving clinical and broad genetic testing in consecutive sudden cardiac arrest (SCA) population. Determining the pathogenesis of non-ischemic SCA is crucial for management and SCA prevention in other family members METHODS: Families with unexplained non-ischemic SCA event underwent rigorous clinical and genetic protocol after referral to our inherited arrhythmia clinic, during 2011-2017. RESULTS: One hundred and four index cases, 29 ± 16 years, and 421 family members were studied. After a thorough evaluation, diagnosis was made in 80 (77%) of families. The most prevalent 47/104 (45%) diagnosis was inherited channelopathy. The genetic test was positive, in 37 /69 (54%) of patients. Using the Mann Whitney test, we found that electrocardiography (ECG) (effect size 0.5, p < .001), 12 lead Holter (effect size 0.33, p = .001) and family screening (effect size 0.4, p = .001) had the highest yield in reaching the final diagnosis. Family screening, genetic testing, and cardiac MRI were the exclusive modalities for final diagnosis in 14%, 9%, and 2% of families, respectively. Among 421 family members evaluated through cascade screening, 127 (30%), were diagnosed and medically treated. Nine family members from 25 (40%) patients who underwent implantable cardioverter defibrillator (ICD) implantation have experienced appropriate ICD shock. CONCLUSIONS: A rigorous, systematic protocol in a specialized inherited arrhythmia clinic has a high diagnostic and prognostic yield. ECG, 12 lead Holter and family screening significantly increased the diagnostic yield. In nine families, without genetic testing, the diagnosis would have been missed.

Prognostic value of cardiac troponin levels in patients presenting with supraventricular tachycardias.

BACKGROUND: An association between paroxysmal supraventricular tachycardias (PSVT) and elevated cardiac troponin I (cTnI) has been reported in small studies, even in the absence of significant coronary artery or structural heart disease. We sought to explore the prognostic significance of elevated cTnI among patients presenting with PSVT. METHODS: This is a retrospective single-center observational study conducted between January 2014 and Decemebr 2016. 165 patients (60% men, mean age 55 ± 17 year-old) with an acute episode of regular supraventricular tachyarrhythmia were admitted to the emergency department at Rambam Medical Center. 131 patients had at least one serum cTnI value measured. Of those, 57 had a positive result, defined as serum cTnI of more than 0.028 ng/dL. RESULTS: Multivariate analysis showed that heart rate > 150 beats per minute (bpm) on admission (OR = 3.9; 95% CI 1.1.6-9.5; p < 0.003) and history of coronary artery disease (CAD) (OR = 3.4; 95% CI 1.2-10.1; p = 0.026) were the only independent predictors of cTnI elevation. After mean follow-up period of 23 ± 7 months, the combined primary outcome of death, coronary intervention (PCI) or myocardial infarction (MI) occurred in 7 patients (12.3%) out of 57 patients with positive cTnI and in zero patients with negative cTn (p = 0.002). Cox proportional hazard model showed that elevated cTnI on admission was an independent predictor of adverse outcomes only in patients with known coronary artery disease (CAD) (HR = 3.3, p = 0.05). CONCLUSION: Elevated cTnI among patients presenting with PSVT appears to have prognostic significance only in patients with history of CAD. In this patient group elevated cTnI is associated with increased risk of adverse cardiac outcomes. We therefore believe serum cTnI should be measured selectively, such as in patients with symptoms of ischemic chest pain and a high pretest likelihood of having CAD.

Specific Therapy Based on the Genotype in a Malignant Form of Long QT3, Carrying the V411M Mutation.

Congenital long QT syndrome (LQTS) is a cardiac channelopathy that leads to the prolongation of the QT interval. This prolongation can lead to ventricular tachyarrhythmia, syncope, and sudden cardiac death. There are various types of LQTS. Treatment of LQT1 and LQT2 is mainly based on antiadrenergic therapy. LQT3, on the other hand, is a result of a mutation of the SCN5A gene, which encodes the sodium channels. In this type, patients are sensitive to vagal stimuli and episodes tend to occur at rest. Sodium channel blocking compounds, such as ranolazine, mexiletine, and flecainide, have been found to be effective in selective mutations.In this case report, we report the case of a child with congenital LQT3 (V411M) who presented first with sudden cardiac death and three weeks later with an implantable cardioverter defibrillator storm. Knowing the specific mutation and understanding the mechanism at the molecular level through an in vitro study yielded a clinically meaningful result. The patient's arrhythmia burden was totally eliminated following successful treatment with flecainide.

Arrhythmic burden among asymptomatic patients with ischemic cardiomyopathy and an implantable cardioverter-defibrillator.

BACKGROUND: The clinical benefit of primary prevention implantable cardioverter-defibrillator (ICD) therapy in asymptomatic patients (New York Heart Association [NYHA] functional class I) with ischemic cardiomyopathy and left ventricular dysfunction is continually disputed. OBJECTIVE: The purpose of this study was to evaluate the incidence of ventricular arrhythmias, mortality rates, and appropriate device therapies by NYHA class in a prospective national ICD registry. METHODS: The study comprised 1670 consecutive patients with ischemic cardiomyopathy who were implanted with a primary prevention ICD and enrolled in the prospective national Israeli ICD Registry from 2010. The risk for clinical and arrhythmic events was assessed by NYHA class. RESULTS: Asymptomatic patients (NYHA I) composed 19% of the study cohort. Comparison according to NYHA class showed that the highest mortality rate was in the NYHA III-IV group vs NYHA I and NYHA II (10.5% vs 5.4% and 5.8%, respectively; log rank P = .003). Conversely, cumulative incidence of appropriate ICD therapies, corrected for death as a competing risk, were higher among patients with NYHA I (11% vs 7%; P = .021). In a multivariate model, NYHA I vs ≥II remained independently associated with a significant 2-fold risk for appropriate ICD therapy (hazard ratio 2.03; 95% confidence interval 1.28-3.24). CONCLUSION: Our findings indicate that patients with ischemic cardiomyopathy without heart failure symptoms have a higher risk of appropriate ICD therapy compared with symptomatic patients after adjustment for the competing risk of death, suggesting possible incremental benefit of primary ICD implantation in this population.

Risk of death without appropriate defibrillator shock in patients with advanced renal dysfunction.

AIMS: Heart failure patients with advanced chronic kidney disease (CKD) may experience an increased rate of non-arrhythmic mortality due to associated comorbidities. We aimed to evaluate the risk of mortality without appropriate implantable cardioverter-defibrillator (ICD) shocks in this high-risk population. METHODS AND RESULTS: The study population comprised 3542 patients who received an ICD, were enrolled, and prospectively followed-up in the Israeli ICD registry. Study patients were categorized into two groups: those with advanced CKD [defined by a glomerular filtration rate of <30 mL/min/1.73 m2 or being on dialysis at time of implantation (n = 197)], and those without advanced CKD (n = 3344). The primary endpoint was the risk of death without receiving appropriate ICD shock. Kaplan-Meier survival analysis showed that at 5 years of follow-up the rates of death without prior ICD shock were significantly higher in the advanced kidney disease group (46%) compared with the non-advanced CKD group (19%; log-rank P-value <0.001). Consistently, multivariate analysis showed that the risk of death without receiving appropriate ICD shock therapy at 5 years was 2.5-fold (P < 0.001) higher among advanced CKD patients. In contrast, the rate of appropriate ICD shock therapy at 5 years among advanced CKD patients was only 9%, with a very high mortality rate (63%) within 3.5 years subsequent to shock therapy. CONCLUSION: Nearly one-half of ICD with advanced CKD die within 5 years without receiving an appropriate ICD shock. These findings stress the importance of appropriate patient selection for primary ICD implantation in this high-risk population.

Arrhythmic Events in Brugada Syndrome: A Nationwide Israeli Survey of the Clinical Characteristics, Treatment; and Long-Term Follow-up (ISRABRU-VF).

BACKGROUND: Limited information exists about detailed clinical characteristics and management of the small subset of Brugada syndrome (BrS) patients who had an arrhythmic event (AE). OBJECTIVES: To conduct the first nationwide survey focused on BrS patients with documented AE. METHODS: Israeli electrophysiology units participated if they had treated BrS patients who had cardiac arrest (CA) (lethal/aborted; group 1) or experienced appropriate therapy for tachyarrhythmias after prophylactic implantable cardioverter defibrillator (ICD) implantation (group 2). RESULTS: The cohort comprised 31 patients: 25 in group 1, 6 in group 2. Group 1: 96% male, mean CA age 38 years (range 13-84). Nine patients (36%) presented with arrhythmic storm and three had a lethal outcome; 17 (68%) had spontaneous type 1 Brugada electrocardiography (ECG). An electrophysiology study (EPS) was performed on 11 patients with inducible ventricular fibrillation (VF) in 10, which was prevented by quinidine in 9/10 patients. During follow-up (143 ± 119 months) eight patients experienced appropriate shocks, none while on quinidine. Group 2: all male, age 30-53 years; 4/6 patients had familial history of sudden death age < 50 years. Five patients had spontaneous type 1 Brugada ECG and four were asymptomatic at ICD implantation. EPS was performed in four patients with inducible VF in three. During long-term follow-up, five patients received ≥ 1 appropriate shocks, one had ATP for sustained VT (none taking quinidine). No AE recurred in patients subsequently treated with quinidine. CONCLUSIONS: CA from BrS is apparently a rare occurrence on a national scale and no AE occurred in any patient treated with quinidine.

Multisite cardiac resynchronization therapy for traditional and non-traditional indications.

PURPOSE: Multisite cardiac resynchronization therapy (MSCRT) with dual-vein left ventricular (LV) pacing has theoretical advantages over conventional CRT in faster and more physiological LV activation. We aimed to define indications, feasibility, safety, acute, and long-term results of MSCRT. METHODS: All patients implanted with MSCRT during 2008-2014 in a single center were reviewed and analyzed. RESULTS: Thirty-nine patients (90% CRT-defibrillators, 64 ± 9 years, 85% male, 74% ischemic etiology) were included. Four groups of indications were recognized: (1) significant tricuspid regurgitation (TR) in patients planned for device implantation without right ventricular lead (n = 3). Follow-up (f/u) of 4 ± 3 years showed major symptomatic improvement in all, with stable LV size and function and deferral of valve surgery; (2) severe heart failure with reduced ejection fraction (HFrEF) and refractory ventricular tachycardia (VT) (n = 4). Except for 1 early death for acute renal failure, all others showed no VT episodes and HF improvement (f/u 4.5 ± 0.5 years); (3) severe HFrEF and wide QRS (≥ 150 ms) or failure of biventricular pacing to narrow QRS during implantation (n = 5). One patient had periprocedural mortality. The others had major clinical improvement; (4) severe HF and narrow QRS/RBBB (n = 27). 23/24 patients with available f/u of 3 ± 1.7 years improved clinically and 57% had EF improvement. In 3 patients, LV1 was disabled and one had LV2 dislodgement. CONCLUSIONS: MSCRT is feasible, safe, and valuable in selected patients with a need to avoid RV lead during device implantation, refractory VT with no other solution, severe HFrEF with wide QRS or CRT non-responsiveness, and severe HF without LBBB. Randomized controlled studies are required.

Impact of quadripolar LV leads on heart failure hospitalization rates among patients implanted with CRT-D: data from the Israeli ICD Registry.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an effective treatment for heart failure (HF); however, a third of patients are non-responders. The development of quadripolar left ventricular (LV) lead was shown, mainly in single manufactures' registry, to improve LV remodeling and overall mortality. However, limited reports exist on the impact of quadripolar LV leads on HF hospitalization rates in real-life cohorts. We evaluated the clinical outcomes associated with quadripolar LV leads in a large nation-wide registry including all patients implanted with a cardiac resynchronization therapy with defibrillator (CRT-D). METHODS: Between July 2010 and October 2016, 2913 consecutive patients were implanted with a CRT-D and all were prospectively enrolled in the Israeli ICD Registry. Quadripolar LV leads were implanted in 973 (33.4%) patients during this period, and their clinical outcomes were compared to CRT-D recipients implanted with a bipolar LV lead. Primary endpoint was HF hospitalization rate. RESULTS: Quadripolar leads were implanted more in patients with non-ischemic cardiomyopathy and for primary prevention indication and less in post-infarction patients and for secondary prevention of sudden death. Longer QRS duration was observed with quadripolar leads (147 ± 23 vs 143 ± 25; p < 0.001). Outcome event rate for 100 patient years revealed no difference in HF hospitalization rates between bipolar and quadripolar LV leads. Quadripolar lead implant led to lower cardiac mortality, with no influence on overall mortality. Multivariate analysis revealed no significant differences in study endpoints between bipolar and quadripolar LV leads. CONCLUSION: In a large real-life registry, implantation of quadripolar LV leads in patients with CRT-D did not influence HF hospitalization rates.

Comparison of the Efficacy of PVAC® and nMARQ™ for paroxysmal atrial fibrillation.

Pulmonary vein isolation (PVI) has become the mainstay of therapy for atrial fibrillation (AF) and one of the most frequently performed procedures in the cardiac electrophysiology laboratory. PVI by a single-tip radiofrequency (RF) ablation catheter remains a complex and time-consuming procedure, especially in centers with limited experience. In order to simplify the PVI procedure, to shorten it and reduce the complication rate, circular multi-electrode catheters were introduced for simultaneous mapping and ablation. The common concept of these "single-shot" AF ablation technologies is the creation of circular lesions for PVI by placing the ablation device at the antrum of the pulmonary veins without the need for continuous repositioning. In this review we describe the main features of two circular non-balloon ablation catheters- PVAC®, which is based on the phased RF, duty-cycled ablation technology, and nMARQ™, the irrigated multi-electrode electro-anatomically guided catheter - and compare the clinical outcomes of these technologies, mainly for paroxysmal AF patients, based on current available data.

Anemia and the Risk of Life-threatening Ventricular Tachyarrhythmias from the Israeli Implantable Cardioverter Defibrillator Registry.

Anemia was shown to be associated with increased risk for adverse events in patients with heart failure (HF). However, there are limited data on the association between anemia and the risk for ventricular arrhythmias (VAs) in patients with an implantable cardioverter defibrillator (ICD). The present study population comprised 2,352 patients who were enrolled and prospectively followed up in the Israeli ICD Registry. The risk for a first appropriate ICD shock for VA was assessed by the presence of anemia, categorized at the lower tertile of hemoglobin distribution (≤12 g/dL [n = 753]). Patients who had anemia displayed higher risk clinical characteristics including older age, more advanced HF symptoms, and atrial fibrillation (p <0.01 for all). Kaplan-Meier survival analysis showed that at 2.5 years of follow-up the rate of appropriate shocks was significantly higher in patients with low (11%) versus high (6%) hemoglobin (log-rank p <0.005). Multivariate analysis showed that anemia was independently associated with a significant 56% increased risk for first appropriate ICD shock (p <0.026). When hemoglobin was assessed as a continuous measure, each 1 g/dL reduction in hemoglobin was independently associated with a significant 8% increased risk for first appropriate shock (p <0.03). Anemia was also associated with increased risk for all-cause mortality (hazard ratio [HR] 1.78, 95% confidence interval [CI] 1.4 to 2.27], p <0.001), HF hospitalizations or death (HR 1.78, 95% CI 1.48 to 1.13, p <0.001), but not with inappropriate ICD shocks (HR 1.24, 95% CI 0.70 to 2.21, p = 0.47). In conclusion, our findings suggest that the presence of anemia in patients with ICD is associated with increased risk for VA during long-term follow-up.

Red cell distribution width predicts death and appropriate therapy in patients with implantable cardioverter defibrillator: A simple measurement with prognostic value in a variety of diseases, may help in better selection of patients who will benefit the most from this device.

BACKGROUND: Red cell distribution width (RDW) is a measure of the size variation of erythrocytes. Its prognostic value has been described in a variety of cardiac and noncardiac diseases. Implantable cardioverter defibrillator (ICD) is useful in preventing sudden cardiac death in high-risk patients, but many of these patients continue to survive without needing ICD therapy. We sought to examine whether RDW, with its prognostic values, can benefit in risk stratification of patients with ICD by predicting death and ICD therapy, and thus help in the selection of patients who will benefit the most from ICD, and minimizing its implantation in others at low risk of death and arrhythmias. METHODS: In a retrospective study, we enrolled patients with ICD implanted for both primary and secondary prevention of sudden cardiac death. Baseline RDW values, demographics, and clinical characteristics, as well as the occurrence of death or first appropriate ICD therapy in postimplantation follow-up were collected. We examined whether RDW can predict higher-risk ICD-implanted patients prone to death and first appropriate ICD therapy (the combined outcome). RESULTS: Final population included 432 patients. Compared to others, patients in the upper RDW tertile were older and had more comorbidities and outcomes. In multivariate analysis including RDW, age, gender, and ejection fraction, RDW was the only predictor of the combined outcome. CONCLUSION: RDW may be useful in risk stratification of patients selected for ICD implantation. But larger prospective randomized trials are needed.

Morbidity and mortality with cardiac resynchronization therapy with pacing vs. with defibrillation in octogenarian patients in a real-world setting.

AIMS: Cardiac resynchronization therapy (CRT) with a defibrillator (CRT-D) has downsides of high cost and inappropriate shocks compared to CRT without a defibrillator (CRT-P). Recent data suggest that the survival benefit of implantable cardioverter defibrillator (ICD) therapy is attenuated in the older age group. We hypothesized that, among octogenarians eligible for cardiac resynchronization therapy, CRT-P confers similar morbidity and mortality benefits as CRT-D. METHODS AND RESULTS: We compared morbidity and mortality outcomes between consecutive octogenarian patients eligible for CRT therapy who underwent CRT-P implantation at Barzilai MC (n = 142) vs. those implanted with CRT-D for primary prevention indication who were prospectively enrolled in the Israeli ICD Registry (n = 104). Among the 246 study patients, mean age was 84 ± 3 years, 74% were males, and 66% had ischaemic cardiomyopathy. Kaplan-Meier survival analysis showed that at 5 years of follow-up the rate of all-cause mortality was 43% in CRT-P vs. 57% in the CRT-D group [log-rank P = 0.13; adjusted hazard ratio (HR) = 0.79, 95% CI 0.46-1.35, P = 0.37]. Kaplan-Meier analysis also showed no significant difference in the rates of the combined endpoint of heart failure or death (46 vs. 60%, respectively, log-rank P = 0.36; adjusted HR was 0.85, 95% CI 0.51-1.44, P = 0.55). A Cox proportional hazard with competing risk model showed that re-hospitalizations for cardiac cause were not different for the two groups (adjusted HR 1.35, 95% CI 0.7-2.6, P = 0.37). CONCLUSION: Our data suggest that, in octogenarians with systolic heart failure, CRT-P therapy is associated with similar morbidity and mortality outcomes as CRT-D therapy.

Contemporary rates and outcomes of single- vs. dual-coil implantable cardioverter defibrillator lead implantation: data from the Israeli ICD Registry.

AIMS: Dual-coil leads were traditionally considered standard of care due to lower defibrillation thresholds (DFT). Higher complication rates during extraction with parallel progression in implantable cardioverter defibrillator (ICD) technology raised questions on dual coil necessity. Prior substudies found no significant outcome difference between dual and single coils, although using higher rates of DFT testing then currently practiced. We evaluated the temporal trends in implantation rates of single- vs. dual-coil leads and determined the associated adverse clinical outcomes, using a contemporary nation-wide ICD registry. METHODS AND RESULTS: Between July 2010 and March 2015, 6343 consecutive ICD (n = 3998) or CRT-D (n = 2345) implantation patients were prospectively enrolled in the Israeli ICD Registry. A follow-up of at least 1 year of 2285 patients was available for outcome analysis. The primary endpoint was all-cause mortality. Single-coil leads were implanted in 32% of our cohort, 36% among ICD recipients, and 26% among CRT-D recipients. Secondary prevention indication was associated with an increased rate of dual-coil implantation. A significant decline in dual-coil leads with reciprocal incline of single coils was observed, despite low rates of DFT testing (11.6%) during implantation, which also declined from 31 to 2%. In the multivariate Cox model analysis, dual- vs. single-coil lead implantation was not associated with an increased risk of mortality [hazard ratio (HR) = 1.23; P= 0.33], heart failure hospitalization (HR = 1.34; P=0.13), appropriate (HR = 1.25; P= 0.33), or inappropriate ICD therapy (HR = 2.07; P= 0.12). CONCLUSION: Real-life rates of single-coil lead implantation are rising while adding no additional risk. These results of single-coil safety are reassuring and obtained, despite low and contemporary rates of DFT testing.