Search

BACKGROUND: Medical treatment of inappropriate sinus tachycardia (IST) remains suboptimal. Radiofrequency sinus node (RF-SN) ablation has poor success and higher complication rates. OBJECTIVE: We aimed to compare clinical outcomes of the novel SN sparing hybrid ablation technique with those of RF-SN modification for IST management. METHODS: This is a multicenter prospective registry comparing the SN sparing hybrid ablation strategy with RF-SN modification. The hybrid procedure was performed using an RF bipolar clamp, isolating superior vena cava/inferior vena cava with the creation of a lateral line across the crista terminalis while sparing the SN region (identified by endocardial 3-dimensional mapping). RF-SN modification was performed by endocardial and/or epicardial mapping and ablation at the site of earliest atrial activation. RESULTS: Of the 100 patients (hybrid ablation group, n = 50; RF-SN group, n = 50), 82% were women, and the mean age was 22.8 years. Normal sinus rhythm and rate were restored in all patients in the hybrid group (vs 84% in the RF-SN group; P = .006). Hybrid ablation was associated with significantly better improvement in mean daily heart rate and peak 6-minute walk heart rate compared with RF-SN ablation. The RF-SN group had a significantly higher rate of redo procedures (100% vs 8%; P < .001), phrenic nerve injury (14% vs 0%; P = .012), lower acute pericarditis (48% vs 92%; P < .0001), permanent pacemaker implantation (50% vs 4%; P < .0001) than did the hybrid ablation group. CONCLUSION: The novel sinus node sparing hybrid ablation procedure appears to be more efficacious and safer in patients with symptomatic drug-resistant IST with long-term durability than RF-SN ablation.

BACKGROUND Arrhythmia-induced cardiomyopathy (AIC) is characterized by improvement in left ventricular ejection fraction (LVEF) following arrhythmia treatment. Predictors of recovery in LVEF are not well understood. OBJECTIVE We evaluated predictors of AIC recovery in a large multicenter cohort. METHODS In total, 243 patients (age 65 ± 11, 73% male) with AIC caused by atrial fibrillation (49%), atrial tachycardia (20%), and premature ventricular contractions (PVCs; 31%) were treated and included. LVEF was assessed before and after treatment. Patients were stratified by arrhythmia duration (known [KN, n = 132] vs. unknown [UKN, n = 111]), arrhythmia type, LVEF, and presence of structural heart disease (SHD). RESULTS Arrhythmia treatment was rhythm control in 95%. Median arrhythmia duration in the KN group was 47 months (25-75th percentile, 24-80 months). Post treatment LVEF was higher in KN group (55.9 ± 7 vs. 46.2 ± 12%; p

Sentinel cerebral embolic protection devices (CPDs) may limit periprocedural cerebrovascular events by preventing micro and macro-embolization to the brain, and has been used in many cardiology and radiology procedures. We hereby report the use of a Sentinel CPD to facilitate safe and effective atrial fibrillation ablation in a patient with a left atrial mass arising from the interatrial septum.

Introduction Prospective studies on rivaroxaban and apixaban have shown the safety and efficacy of direct anticoagulation agents (DOAC)s used peri-procedurally during radiofrequency ablation (RFA) of atrial fibrillation (AF). Studies comparing the two agents have not been performed. Methods Consecutive patients from a prospective registry who underwent RFA of AF between April 2012 and March 2015 and were on apixaban or rivaroxaban were studied. Clinical variables and outcomes were noted. Results There were a total of 358 patients (n = 56 on apixaban and n = 302 on rivaroxaban). There were no differences in baseline characteristics between both groups. The last dose of rivaroxaban was administered the night before the procedure in 96% of patients. In patients on apixaban, 48% of patients whose procedure was in the afternoon took the medication on the morning of the procedure. TIA/CVA occurred in 2 patients (0.6%) in rivaroxaban group with none in apixaban group (p = 0.4). There was no difference in the rate of pericardial effusion between apixaban and rivaroxaban groups [1.7% vs 0.6% (p = 0.4)]. Five percent of patients in both groups had groin complications (p = 0.9). In apixaban group, all groin complications were small hematomas except one patient who had a pseudoaneurysm (1.6%). One pseudo-aneurysm, 1 fistula and 3 large hematomas were noted in patients on rivaroxaban (1.7%) with the rest being small hematomas. DOACs were restarted post procedure typically 4 h post hemostasis. Conclusions Peri-procedural uninterrupted use of apixaban and rivaroxaban during AF RFA is safe and there are no major differences between both groups.

The STROKE-VT (Safety and Efficacy of Direct Oral Anticoagulant Versus Aspirin for Reduction of Risk of Cerebrovascular Events in Patients Undergoing Ventricular Tachycardia Ablation) study is a multicenter, randomized controlled trial that examined the differences in cerebrovascular events between direct oral anticoagulant (DOAC) and aspirin (ASA) use postprocedurally in patients who underwent left ventricular arrhythmia (LVA) ablation (ventricular tachycardia [VT] or premature ventricular contraction [PVC]) using radiofrequency ablation (RFA).There exists limited data regarding antiplatelet or anticoagulation strategy following LVA ablation.A total of 246 patients scheduled for LVA-RFA were randomized 1:1 postprocedurally to receive DOACs or ASA. The study's primary endpoint was the incidence of stroke or transient ischemic attack (TIA) or asymptomatic cerebrovascular events (ACEs) detected by magnetic resonance imaging at 24 hours and 30 days of follow-up. The secondary endpoints included procedure-related complications (composite of any vascular complication, pericardial complication, heart block, and thromboembolic event, excluding stroke or TIA) and in-hospital mortality.There were no differences between groups regarding baseline and ablation characteristics (except the percentage of patients who underwent VT ablation, rate of amiodarone use, and total RFA time). Postprocedure cerebrovascular events (stroke and TIA) were lower in the DOAC arm versus the ASA arm (0% vs 6.5%; P 0.001 and 4.9% vs. 18%; P 0.001, respectively). Patients in the ASA group had more MRI-detected ACEs compared with the DOAC group both at 24-hour (23% vs 12%; P = 0.03) and 30-day (18% vs 6.5%; P = 0.006) follow-up. Acute procedure-related complications and in-hospital mortality were similar between the 2 groups.DOAC use following endocardial and/or epicardial ablation for LVA-RFA was associated with reduced risk of TIA or stroke and asymptomatic MRI-detected cerebrovascular events.

Introduction: The role of remote magnetic navigation (RMN) for ventricular tachycardia (VT) ablation is not well established. In this meta- analysis, we aim to evaluate the safety and efficacy of RMN vs manual navigation (MAN) for VT ablation. Methods: A comprehensive literature search in PubMed, Google Scholar and Cochrane Review from inception till November 9th, 2019 was performed. Studies reporting clinical outcomes comparing MAN vs RMN were included. Two investigators independently extracted the data and individual quality assessment was performed. Results were expressed as odds ratio (OR) for dichotomous outcomes and mean differences (MD) for continuous variables with 95% confidence intervals (CI). Results: Eight studies including a total of 861 patients (475 in RMN arm and 386 in MAN arm) were included in the final analysis. VT recurrence was significantly lower with RMN compared with MAN (OR 0.65, 95% CI 0.48-0.88, p= 0.005). Acute procedural success was significantly higher with RMN (OR 2.21, 95% CI 1.51-3.23, p < 0.0001). Total procedure time [MD -8.83, 95% CI -17.72- 0.05, p=0.05], fluoroscopy time [MD -10.24, 95% CI -12.28- -8.19, p= 0.00001), and complications [OR 0.36, 95% CI 0.18- 0.72, p= 0.003] were significantly lower in RMN compared to MAN. Conclusion: Results of our meta-analysis indicate that RMN is safer and more effective than MAN in patients with VT undergoing ablation. Further, randomized studies are needed to validate these findings.

Background: Patients undergoing bariatric surgery are prone to develop symptomatic dysautonomia but the mechanisms remain unclear. Methods: N/A Results: A 61-year-old female with hyperlipidemia, fibromyalgia, morbid obesity status post gastric sleeve 2 years prior, was transferred to our institution after an unremarkable initial cardiac workup for recurrent syncope and bradycardia. Patient had significant weight loss (180 lbs) post-surgery over this 2-year period but began noticing increasing fatigue, and exercise intolerance in the last four months preceding recent syncopal episodes. Syncopal spells happened while trying to lift her head >60 degrees/sit up from a recumbent position. Baseline heart rate (HR) was 36-42 bpm (Figure lower Panel) while it was 75-90 bpm immediately following bariatric surgery (Figure upper panel). Blood pressure was normal. During witnessed syncopal episodes, HR remained in the 35-40 bpm range with no asystolic pauses and normal blood pressure. Video EEG showed loss of brain electrical activity during syncope; no seizure activity was noted. Progressive decline in HR and baseline bradycardia was suspected as the cause and she underwent permanent pacemaker implantation, which resulted in complete resolution of symptoms and no recurrence of syncope at 6-mo follow-up. Conclusion: We describe a unique case where marked decline in resting HR occurred in association with significant weight loss following bariatric surgery. This ‘HR deficit’ and resting bradycardia, likely due to dysautonomia, resulted in recurrent syncope without asystole or vasodepression, and completely resolved with permanent pacemaker implantation.

Background: The STROKE-VT is an ongoing, multicenter, randomized controlled trial that studies the differences in cerebrovascular events between DOAC vs ASA use post procedurally in ischemic and non-ischemic cardiomyopathy patients undergoing left ventricular tachycardia radiofrequency ablation (VT RFA). Methods: 52 Eligible patients scheduled for VT RFA were randomized 1:1 post procedurally to a DOAC (n=26; Dabigatran-11/Rivaroxaban-12 & Apixaban-3) or ASA (n=26, 81mg) for 30 days. VT ablation was performed under moderate sedation or general anesthesia either through retrograde aortic (n=28) or transseptal (n=24) approach. All patients were given IV heparin for ACT>300msec. Study drug was administered 3 hours after hemostasis. A brain MRI was done within 6-12 hours post VTRFA and at 30 days. NIH stroke scale was used to assess for neurological changes before, after and at 30 day follow up. Results: 52 patients (M:F- 4.2:1) with 55% ICM were enrolled. DOAC group was slightly older (65±8 vs 60±6 yrs, p=0.04)), had longer procedural (186±76 vs 150±51, p Conclusions: DOAC decrease the incidence of delayed ACE after VTRFA. However, retrograde aortic approach and prolonged procedural and RFA time can increase the risk of acute ACE.

As the coronavirus cases continue to surge, the urgent need for universal testing to identify positive cases for effective containment of this highly contagious pandemic has become the center of attention worldwide. However, in spite of extensive discussions, very few places have even attempted to implement it. We evaluated the efficacy of widespread testing in creating a safe workplace in our electrophysiology (EP) community. Furthermore, we assessed the new infection rate in patients undergoing EP procedure, to see if identification and exclusion of positive cases facilitated establishment of a risk-free operating environment. Viral-RNA and serology tests were conducted in 1670 asymptomatic subjects including patients and their caregivers and staff in our EP units along with the Emergency Medical Service (EMS) staff. Of 1670, 758 (45.4%) were patients and the remaining 912 were caregivers, EMS staff, and staff from EP clinic and lab. Viral-RNA test revealed 64 (3.8%) positives in the population. A significant increase in positivity rate was observed from April to June 2020 (p = 0.02). Procedures of positive cases (n = 31) were postponed until they tested negative at retesting. Staff testing positive (n = 33) were retested before going back to work after 2 weeks. Because of suspected exposure, 67 staff were retested and source was traced. No new infections were reported in patients during or within 2 weeks after the hospital-stay. Universal testing to identify positive cases was helpful in creating and maintaining a safe working environment without exposing patients and staff to new infections in the EP units. Trial Registration Number: clinicaltrials.gov : NCT04352764

Background No comparative study of outcomes in Riata and Sprint Fidelis leads undergoing lead extraction (LE), lead abandonment (LA), and generator change only (GC) has been published. Objectives Determine outcomes (major complications [MC]; death, extended hospitalization, or rehospitalization within 60 days [RH]; lead malfunction) of LE, LA, and GC for recalled leads. Methods Retrospective, multicenter, comparative study. Results A total of 298 LE, 85 LA, and 310 GC were performed. In the clinical setting of a lead intervention, there was no difference in a composite of MC, death, RH, lead revision, inappropriate shocks, or device infection between LE and LA groups (15% vs 22%, P = .140). In the clinical setting of a device at elective replacement interval (ERI), there were significantly more acute events at 60 days (MC, death, and RH) in the LE and LA groups at 15.4% (4) and 15.4% (4), and this was significantly (P = .017) higher than the GC group at 5.1% (16). There was no difference (P = 1.000) in the composite of MC, death, RH, lead malfunction, lead revisions, device infections, or inappropriate shocks between LE, LA, and GC groups at 15.4% (4), 15.4% (4), and 17.4% (54), respectively. Following generator change, 14 of 175 Fidelis leads and 3 of 135 Riata leads failed over a total of 12,714 months of follow-up. Conclusions The failure rate of recalled leads was substantially lower compared to previous reports. It may be prudent to perform generator change only when the device is at ERI, especially when the recalled lead has historical performance that likely outweighs the risks of extraction/abandonment.

Background Single-chamber leadless pacemakers (LPs) have been shown to be an effective alternative to conventional transvenous pacemakers (CTPs), but their benefit in the context of cardioinhibitory vasovagal syncope (CI-VVS) is unknown. Objective The purpose of this study was to evaluate the safety and efficacy of LP compared with dual-chamber CTP for CI-VVS. Methods We conducted a multicenter, retrospective study comparing patients who received LP or dual-chamber CTP for drug-refractory CI-VVS. CI-VVS was diagnosed clinically and supported by cardiac monitoring and head-up tilt table testing. The primary efficacy endpoint was freedom from syncope during follow-up. Secondary endpoints included device efficacy and safety estimated by device-related major and minor adverse events (AEs). Results Seventy-two patients (24 LP, 48 CTP; age 32 ± 5.5 years; 90% female; syncope frequency 7.6 ± 3.4 per year) were included. At 1 year, 91% of patients (22/24) in the LP group and 94% of patients (43/48) in the CTP group met the primary efficacy endpoint (P = .7). Device efficacy endpoint was met in 92% of the LP group and 98% of the CTP group (P = .2). Early major AEs occurred in 2 of 24 in the LP group and 3 of 48 in the CTP group (P = .4). Late major AEs occurred in 0 of 24 in the LP group and 2 of 48 in the CTP group (P = 1). Conclusion In patients with CI-VVS, single-chamber LP demonstrated equivalent efficacy in reducing syncopal events compared to dual-chamber CTP, with a similar safety profile.

Persistent left superior vena cava (PLSVC) is one of the most frequently reported congenital anomalies and may be an important source of trigger of atrial fibrillation (AF). This was a multicenter retrospective experience including 28 patients with PLSVC who were referred for catheter ablation for drug-refractory symptomatic AF. Pulmonary vein and PLSVC isolation were performed (3.5-mm open irrigated tip ablation catheter at maximum power of 20 W, maximum temperature 43 °C with flow rate of 17 ml/min). Clinical outcomes such as complications and long-term freedom from AF were measured. The mean age of the population was 61 ± 8 years, 21% were females, and AF duration was 60 ± 33 months. Sixty-one percent paroxysmal AF (17/28), 25% (7/28) persistent AF, and 14% (4/28) had long-standing persistent AF. There were no major complications that required any intervention. PLSVC isolation was achieved in 96% (27/28). Freedom from AF at 1 year without antiarrhythmic drugs was seen in 75% (21/28) of patients. In PLSVC patients with AF, segmental isolation of PLSVC appears to be feasible and safe and can translate into favorable clinical outcomes.

Background Percutaneous left atrial appendage exclusion (LAAE) has evolved as an alternative strategy for stroke prevention in atrial fibrillation (AF). Recent observational data have suggested that epicardial LAAE can have substantial impact on arrhythmia burden and hemodynamic profile. Objectives The authors aimed to study the impact of epicardial versus endocardial LAAE on systemic blood pressure in hypertensive AF patients. Methods This was a prospective, nonrandomized study comparing 247 patients who underwent epicardial LAAE with 124 patients with endocardial exclusion. Clinical outcomes were measured at 3 months and 1 year. Primary outcome was improvement in systolic blood pressure (SBP) between both groups compared with baseline. Secondary outcome included changes in diastolic pressures (DBP), serum electrolytes, and creatinine. Results There was no significant difference in baseline SBP between epicardial and endocardial groups. SBP was significantly lower in the epicardial group both at 3 months (122 ± 11.8 mm Hg vs. 129.7 ± 8.2 mm Hg; p Conclusions In hypertensive AF patients, epicardial LAAE significantly decreases SBP both at 3 and 12 months compared with endocardial exclusion.

Background: Premature ventricular contractions are a common clinical presentation that drives further diagnostic workup. We hypothesize the presence of underlying inflammation is often unrecognized in these patients with a potential for continued disease progression if not diagnosed and treated early in the disease course. Methods: This is a single-center, prospective study including 107 patients with frequent symptomatic premature ventricular contractions (>5000/24 h) and no known ischemic heart disease. Patients underwent a combination of laboratory testing, 18F-fluorodeoxyglucose positron emission tomography scan, cardiac magnetic resonance imaging, and biopsy. Patients were diagnosed with myocarditis based on a multidisciplinary approach and treated with immunosuppressive therapy. Results: The mean age of the cohort was 57±15 years, 41% were males, and left ventricular ejection fraction was 47±11.8%. Positive positron emission tomography scan was seen in 51% (55/107), of which 51% (28/55) had preserved left ventricle function. Based on clinical profile, 18F-fluorodeoxyglucose—positron emission tomography imaging, cardiac magnetic resonance, and histological data 58% patients (32/55) received immunosuppressive therapy alone and 25.4% (14/55) received immunosuppressive therapy and catheter ablation. Optimal response was seen in 67% (31/46) over a mean follow-up of 6±3 months. In patients with left ventricle systolic dysfunction, 37% (10/27) showed an improvement in mean left ventricular ejection fraction of 13±6%. Conclusions: Approximately 51% of patients presenting with frequent premature ventricular contractions have underlying myocardial inflammation in this cohort. 18F-fluorodeoxyglucose—positron emission tomography scan can be a useful modality for early diagnosis and treatment with immunosuppressive therapy in selected patients can improve clinical outcomes.

BACKGROUND The safety of perioperative anticoagulation (AC) and antiplatelet (AP) therapy with subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation is unknown. The purpose of this study was to identify the risk factors associated with hematoma complicating S-ICD implantation. METHODS Records were retrospectively reviewed from 200 consecutive patients undergoing S-ICD implantation at two academic medical centers. A hematoma was defined as a device site blood accumulation requiring surgical evacuation, extended hospital stay, or transfusion. RESULTS Among 200 patients undergoing S-ICD implantation (age 49 ± 17 years, 67% men), 10 patients (5%) had a hematoma, which required evacuation in six patients (3%). Warfarin was bridged or uninterrupted in 12 and 13 patients, respectively (6% and 6.5%). Four of 12 patients with warfarin and bridging AC (33%) and two of 13 patients with uninterrupted warfarin (15%) developed a hematoma. Neither of the two patients with uninterrupted DOAC had a hematoma. No patients on interrupted AC without bridging (n = 26, 13 with warfarin, 13 with DOAC) developed a hematoma. A hematoma was also more likely with the use of clopidogrel (n = 4/10 vs 10/190, 40% vs 5.3%, P

Background The impact of left atrial appendage (LAA) exclusion, comparing an epicardial LAA or an endocardial LAA device, on systemic homeostasis remains unknown. Objectives This study compared the effects of epicardial or endocardial LAA devices on the neurohormonal profiles of patients, emphasizing the roles of the renin-angiotensin-aldosterone system and the autonomic nervous system. Methods This is a prospective, single-center, observational study including 77 patients who underwent LAA closure by an epicardial (n = 38) or endocardial (n = 39) device. Key hormones involved in the adrenergic system (adrenaline, noradrenaline), renin-angiotensin-aldosterone system (aldosterone, renin), metabolic system (adiponectin, free fatty acids, insulin, β-hydroxybutyrate, and free glycerols), and natriuresis (atrial and B-type natriuretic peptides) were assessed immediately before the procedure, immediately after device deployment, at 24 h, and at 3 months follow-up. Results In the epicardial LAA device group, when compared with baseline blood adrenaline, noradrenaline and aldosterone were significantly lower at 24 h and 3 months (p Conclusions There are substantial differences in hemodynamics and neurohormonal effects of LAA exclusion with epicardial and endocardial devices. Further studies are required to elucidate the underlying mechanism of these physiological changes.

Objectives This study sought to evaluate the clinical outcomes of patients receiving hemodynamic support (HS) during ventricular tacchycardia (VT) ablation. Background There are limited real-world data evaluating its effect of HS in ablation outcomes. Methods An analysis of 1,655 patients from the International VT Ablation Center Collaborative group was performed. A total of 105 patients received HS with percutaneous ventricular assist device. Results Patients in the HS group had lower left ventricular ejection fraction (LVEF), higher New York Heart Association (NYHA) functional class, and more implantable cardioverter-defibrillator (ICD) shocks, VT storm, and antiarrhythmic drug use (all p Conclusions Patients requiring HS were sicker with multiple comorbidities and, as expected, had a significantly higher 1-year mortality than did those patients in the no-HS group. In patients with LVEF ≤20% and NYHA functional class III to IV, there was also no significant difference in clinical outcomes when compared with no HS. Further studies are needed to systematically evaluate patients undergoing VT ablation receiving HS.

Objectives The present study describes the use of octreotide (OCT) in patients with atrial fibrillation (AF) receiving oral anticoagulation (OAC) who have gastrointestinal (GI) bleeding related to arteriovenous malformations (AVMs), as well as its effect on OAC tolerance and subsequent rebleeding. Background AVMs cause significant GI bleeding, especially in patients with AF who are receiving OAC for stroke prevention. OCT has been shown to minimize recurrent GI bleeds related to AVMs. Methods In a multicenter, observational study, 38 AF patients with contraindications to OAC because of AVM-related GI bleeding were started on 100 μg of subcutaneous OCT twice daily. OAC was resumed in all patients within 48 h. Incidence of recurrent GI bleeds was calculated, and hemoglobin levels were recorded at enrollment and at 3 and 6 months’ follow-up. Results After a median follow-up of 8 months, 36 patients (mean age 69 ± 8.0 years; mean CHA2DS2-VASc score 3 ± 1 and mean HAS-BLED score 3 ± 1) were available for analysis. All were able to successfully resume OAC, and 28 of 36 (78%) remained on OAC at the conclusion of the study, whereas 8 underwent left atrial appendage closure with subsequent OAC discontinuation. No systemic thromboembolic events occurred in follow-up. Of the 28 patients who continued receiving OAC, 19 (68%) were free of recurrent GI bleed, 4 had minor GI bleeds, 4 required transfusion, and 1 required colectomy for GI bleeding. Mean hemoglobin levels in all patients receiving OAC were significantly higher at 3- and 6-month follow-up than at baseline (p Conclusions Subcutaneous OCT therapy is an attractive option in AF patients receiving OAC who have AVM-related GI bleeds. It allows successful reinitiation of OAC as a bridge to left atrial appendage exclusion or short-term relief from bleeding.

There are limited studies on the safety and efficacy of remote magnetic navigation (RMN) versus manual navigation (MAN) in ventricular tachycardia (VT) ablation. A comprehensive literature search was performed using the keywords VT ablation, stereotaxis, RMN and MAN in Pubmed, Ebsco, Web of Science, Cochrane, and Google scholar databases. The analysis included seven studies (one randomized, three prospective observational, and three retrospective) including 779 patients [both structural heart disease (SHD) and idiopathic VT] comparing RMN (N = 433) and MAN (N = 339) in VT ablation. The primary end point of long-term VT recurrence was significantly lower with RMN (OR 0.61, 95% CI 0.44–0.85, p = 0.003) compared with MAN. Other end points of acute procedural success (OR 2.13, 95% CI 1.40–3.23, p = 0.0004) was significantly higher with RMN compared with MAN. Fluoroscopy [mean difference −10.42, 95% CI −12.7 to −8.1, p

Dofetilide is a class III antiarrhythmic drug that has been reported to be safe and efficacious in the treatment of atrial dysrhythmias with a known initial risk of QT prolongation and torsades de pointes (TdP). As a result, the Federal Drug Administration (FDA) mandated in-hospital dofetilide initiation and adherence to a common dosing protocol. However, there is a lack of clarity on how to manage dofetilide re-initiation.An observational survey was performed including 347 cardiologists in the United States and worldwide to evaluate the deviations from approved manufacturer's protocol during dofetilide initiation and re-initiation among practicing cardiologists.Most practicing cardiologists were cautious about outpatient dofetilide use and adhered to the manufacturer's in-patient dofetilide protocol during de-novo initiation and reported low incidence of TdP in clinical practice. There were substantial differences among practicing cardiologists with deviation from the manufacturer's protocol during re-initiation of dofetilide. About 21% cardiologists always admitted patients to the hospital while 37% admitted patients10% of the time for dofetilide re-initiation. Only 4% reported major adverse events with outpatient dofetilide re-initiation. There was also wide variation regarding monitoring of electrolytes and QT interval as an outpatient with dofetilide.There is significant practice pattern variation in the use of dofetilide for the management of AF. This degree of variation noted is concerning and is a reflection of the current lack of substantial clinical evidence in the re-initiation dofetilide protocol to help direct the provider.

BACKGROUND Implantation of cardiac implanted electronic device (CIED) has surged lately. This resulted in a rise in cardiac device-related infections (CDI) and inevitably, lead extractions. We examined the recent national trend in the incidence of CIED infections and lead extractions in hospitalized patients and associated mortality. METHODS Using the Nationwide Inpatient Sample for the years 2003-2011 we identified patients diagnosed with a CDI-associated infection as determined by discharge ICD-9 diagnostic codes. We examined the trend of device-related infections overall and in different subgroups. We studied mortality associated with device infections, lead extractions, associated costs, and length of stay. RESULTS There is a significant increase in the number of hospitalizations due to CDI from 5,308 in the year 2003 to 9,948 in 2011. Males (68%), Caucasians (77%), and age group 65-84 years (56.4%) accounted for majority of CDI. The mortality associated with CDI was 4.5 %, and was worse in higher age groups (2.5% in 18-44 years compared to 5.3% in 85+ years, P < 0.001). Average length of stay was unchanged over the years remaining at 13.6 days; however, mean hospitalization charges increased from $91,348 in 2003 to $173,211 in 2011 (P < 0.001). Among all lead extraction procedures, the percentage of patients undergoing lead extraction secondary to CDI also increased from 2003 (59.1%) to 2011 (76.7%), P-value < 0.001. CONCLUSIONS Healthcare burden associated with CDI infections and associated lead extractions has significantly increased in the recent years. Despite an increase in cost associated with CIED infections, mortality remains the same, and is higher in older patients.

Background There have been an increasing number of atrial fibrillation (AF) patients with Watchman® left atrial appendage occlusion (LAAO) device, requiring catheter ablation (CA) for maintenance of normal sinus rhythm. In this study, we describe our experience with the feasibility and safety of CA in patients with a preexisting Watchman LAAO device. Methods This was a retrospective multicenter AF registry of 60 patients with Watchman® LAAO device who underwent CA for AF. Baseline clinical and procedural characteristics of the included subjects were retrieved from review of medical records and were analyzed. Results The mean age was 72.7±4.9 years and the mean CHADS2 score was 2.3±0.6. All patients had successful pulmonary vein isolation (PVI). The left atrial appendage (LAA) was electrically active in 34 (56%) while reentrant tachycardia and AF triggers were seen in 17 (28%) patients. Electrical isolation was attempted in these 17 patients with only 10 achieving complete LAA isolation. Repeat imaging showed new peri-device leaks in 30% (12/40) patients, while new significant peri-device leaks (≥5 mm) were noted in 10% (10/40) of patients after RFA, respectively, requiring continuation of oral anticoagulation. There were a higher proportion of patients with severe peri-device leaks (≥5 mm) after LAA isolation. However, >50% of those leaks sealed off on follow-up TEE. Conclusion AF ablation is a feasible and safe in patients with preexisting Watchman LAAO device. Electrical isolation of the LAA could be difficult and when attempted can result in increased risk of short-term peri device leak and recurrence of AT/AF in almost all patients. This article is protected by copyright. All rights reserved

Left atrial appendage closure (LAAC) is a promising site-directed therapy for stroke prevention in patients with non-valvular atrial fibrillation (AF) who are ineligible or contraindicated for long-term oral anticoagulation. A variety of LAAC modalities are available, including percutaneous endocardial occluder devices such as WATCHMAN TM (Boston Scientific Corp., Marlborough, MA, USA), and an ever-increasing body of evidence is helping to define the optimal use of each technique. Similarly increased experience with LAAC has revealed challenges such as device-related thrombi and peri-device leaks for which the long-term significance and appropriate management are areas of active investigation. We review the evolution and long-term outcomes with the WATCHMAN TM device with particular emphasis on the nuances of its use and its role in the broader landscape of appendageology.

Endocardial LAAO has been increasingly utilized in atrial fibrillation (AF) patients who are not suitable for long term oral anticoagulation. While overall procedural complications have decreased, rare complications like contiguous vessel and valve injury may be more frequently seen in the future with increase in the procedure volume. We performed a systematic search using predefined terms which reviewed all cases published in literature of contiguous vessel (pulmonary artery, pulmonary vein and left circumflex artery) and mitral valve injury caused by LAAO devices. Our results showed that Amplatzer Cardiac Plug (ACP) and Amplatzer Amulet devices were the most commonly used devices. Pulmonary artery perforation was the most commonly seen collateral vessel injury associated with LAAO. Close proximity of left atrial appendage to pulmonary artery was noted in all cases of pulmonary artery injury. Pulmonary artery injury commonly manifests as pericardial tamponade with hemodynamic collapse and is often fatal. Most common denominator of all the reviewed cases was the presence of an oversized LAAO device. In conclusion, collateral vessels and valve injury can be seen after LAAO mostly with double lobe devices such as ACP or Amulet. Increased awareness by the operators along with proper imaging and investigations could potentially mitigate such rare complications associated with LAAO.

Electrical isolation of the left atrial appendage (LAA) may provide incremental benefits for arrhythmia management in patients undergoing radiofrequency ablation (RFA) for persistent atrial fibrillation (AF). The aim of this study was to compare efficacy and safety of endocardial ablation and LAA exclusion with LARIAT device for electrical and mechanical exclusion of LAA. We compared patients who underwent endocardial LAA isolation during index RFA for persistent AF and underwent a repeat RFA to patients who underwent LAA exclusion with LARIAT device followed by RFA for AF in this multicenter registry. Efficacy of electrical and mechanical isolation of LAA was assessed. We included 182 patients of which 91 patients underwent endocardial LAA isolation during RFA for AF, and 91 patients underwent LAA exclusion with LARIAT device followed by RFA for AF. Baseline characteristics were similar except for higher CHA2DS2-VASc score, coronary artery disease, and prior stroke rate in LARIAT arm. Persistence of electrical isolation (measured at beginning of second procedure) after LARIAT procedure was higher than one-time AF-RFA (96.7% vs 52.8%, p < 0.01). Acute pulmonary vein isolation rates were similar in both arms. AF recurrence rate after second isolation attempts at 1 year was similar in both arms. No difference in major complications was noted between both arms. LAA exclusion with LARIAT device appears to be more efficacious as compared to one-time endocardial ablation, but not compared to repeat isolation, in achieving complete electrical isolation of LAA for persistent AF.

Use of oral anticoagulation (OAC) in patients with a history of intracranial hemorrhage (ICH) is often considered high risk as OAC-related ICH is associated with high mortality rates. Left atrial appendage closure with a WATCHMAN device is an alternative management strategy to OAC to decrease thrombotic risk in atrial fibrillation patients; however use of OAC followed by dual antiplatelet therapy (DAPT) or DAPT therapy alone is required for 6 months post-procedurally. In this study, we examined the safety of WATCHMAN implantation followed by 6 months of anti-thrombotic therapy in patients with a history of ICH. This is a retrospective analysis of 63 patients with a history of ICH prior to WATCHMAN implantation (Group I) and 95 patients without a history of ICH who underwent WATCHMAN placement (Group II). The primary outcome was death, stroke, or major bleeding within 6 months of WATCHMAN placement. The average CHA2DS2-VASc of Group I was 4.9 ± 1.7 vs 4.7 ± 1.4 for Group II (p = 0.34). The most common type of ICH in Group I was an intracerebral hemorrhage (57%). The median time between ICH and WATCHMAN implantation in Group I patients was 212 days. A total of 19% of Group I patients were managed with DAPT alone post-procedurally vs. 3% in Group II (p

Background Dofetilide is a class III antiarrhythmic drug commonly used for treatment of atrial fibrillation. Drug guidelines mandate a 3-month waiting period before initiating dofetilide after amiodarone use. Whether patients with an implantable cardioverter–defibrillator (ICD) can be rapidly switched from amiodarone to dofetilide is not known. Objective The purpose of this study was to evaluate whether rapid switching from amiodarone to dofetilide is safe in atrial fibrillation patients with an ICD. Methods In this retrospective observational study, we assessed the feasibility and the short- and long-term safety of rapid switching from amiodarone to dofetilide in hospitalized atrial fibrillation with an ICD. Results The study included a total of 179 patients who were followed for 12.6 ± 2.2 months. All patients had drug initiation during hospitalization. Dofetilide resulted in successful cardioversion in 66% (118/179). Twenty percent of patients (36/179) required dofetilide dose adjustments in the initiation phase because of QT prolongation and decreased creatinine clearance. A total of 6.1% of patients (11/179) required drug discontinuation. The incidence of torsades de pointes was 1.1% (2/179) during initiation. One patient (0.5%) had self-terminating ventricular tachycardia at follow-up. No other significant adverse events were noted during follow-up. Conclusion Atrial fibrillation patients with an ICD can be rapidly switched to dofetilide after 7 days of discontinuation of amiodarone without significant arrhythmia-related complications. Prospective studies with large sample sizes, especially of women, should be performed to further validate these findings.

Cardiac implantable electronic devices (CIED) have shown survival benefit in certain patient populations and as these devices continue to gain popularity, complications remain a concern, in particular CIED infection. An absorbable mesh envelope (TYRX, Medtronic), coated with absorbable polymer mixed

Background There is limited data regarding effect of prolonged radiation exposure during electrophysiological (EP) procedures on direct DNA damage. Comet test has shown to assess DNA damage following radiation exposure. Methods We performed a single-center prospective observational study assessing direct DNA damage using the quantitative comet assay in patients undergoing cardiac resynchronization (CRT) and atrial fibrillation (AF) catheter ablation procedures. Venous comet assay was performed pre, immediately post procedure and at 3-month duration in twenty-two (N=22) patients who underwent catheter ablation for symptomatic AF and fourteen (N=14) patients who underwent CRT implantation. Results The median [interquartile range (IQR)] fluoroscopy time, radiation dose and dose area product (DAP) were 34.3 (27.97 - 45.48) minutes, 853.07 (611.36 - 1334.76) mGy and 16,994.10 (9,023.65 - 58,845.00) UGym2 in the ablation group and 30.05 (18.75 - 37.33) minutes, 345.00 (165.09 - 924.79) mGy and 11,837.20 [7182.67 - 35567.75] UGym2 in the CRT group. When compared with pre-procedure, there was a statistically significant increase in median (IQR) DNA migration on comet assay in the ablation group immediately post procedure [+6.55 µm (0.78, 10.25, p=0.02)] that subsequently decreased at 3 months [-1.00 µm (-2.20, 0.78), p=0.03] but not in the CRT group. Conclusion There was a significant increase in DNA damage as detected by comet assay immediately post procedure that normalized at 3 months in patients undergoing AF ablation. Further large prospective studies are warranted to evaluate the impact of this prolonged radiation exposure and DNA damage on long-term follow up.

Background Left atrial (LA) strain (e) and e rate (SR) analysis by 2-dimensional speckle tracking echocardiography is a novel method for functional assessment of the LA. Objective The purpose of this study was to determine the impact of left atrial appendage (LAA) exclusion by Lariat epicardial ligation on mechanical function of the LA by performing e and SR analysis before and after the procedure. Methods A total of 66 patients who underwent successful LAA exclusion were included in the study. Of these 66 patients, 32 had adequate paired data for e and SR analysis. SR during ventricular systole (LA-SRs) represents LA reservoir function, and SR during early ventricular diastole (LA-SRe) represents LA conduit function. e and SR were determined from apical 4- and 2-chamber views using the electrocardiographic QRS as a reference point. LA volume index as surrogate for LA remodeling was measured from apical views. Results Mean patient age was 70 ± 9.2 years. LAA ligation resulted in improved reservoir function (LA-SRs: pre 0.72, confidence interval [CI] 0.63–0.83 vs post 0.81, CI 0.73–0.98; P = .043) and conduit function (LA-SRe: pre 0.74, CI 0.67–0.99 vs post 0.89, CI 0.82–1.07; P = .025). LA volume index improved significantly with the Lariat (pre 35.4, CI 29.4–37.2 vs post 29.2, CI 28.2–35.9; P Conclusion LAA exclusion seems to improve mechanical function of the LA and results in reverse LA remodeling.

Background Atrioventricular node (AVN) ablation and permanent pacing is an established strategy for rate control in the management of symptomatic atrial fibrillation (AF). Leadless pacemakers (LPs) can overcome some of the short-term and long-term limitations of conventional transvenous pacemakers (CTPs). Objectives The purpose of this study was to compare the feasibility and safety of LP with those of single-chamber CTP in patients with AF undergoing AVN ablation. Methods We conducted a multicenter observational study of patients undergoing AVN ablation and pacemaker implantation (LP vs single-chamber CTP) between February 1, 2014 and November 15, 2016. The primary efficacy end points were acceptable sensing (R wave amplitude ≥5.0 mV) and pacing thresholds (≤2.0 V at 0.4 ms) at follow-up. Safety end points included device-related major and minor (early 1 month) adverse events. Results A total of 127 patients with LP (n = 60) and CTP (n = 67) were studied. The median follow-up was 12 months (interquartile range 12–18 months). Ninety-five percent of the LP group and 97% of the CTP group met the primary efficacy end point at follow-up (57 of 60 vs 65 of 67; P = .66). There was 1 major adverse event (loss of pacing and sensing) in the LP group and 2 (lead dislodgement) in the CTP group (1 of 60 vs 2 of 67; P = 1.00). There were 6 minor adverse events (5 early and 1 late) in the LP group and 3 (early) in the CTP group (6 of 60 vs 3 of 67; P = .30). Conclusion Our results demonstrate the feasibility and safety of LP compared with CTP in patients undergoing AVN ablation for AF.

Background: We sought to investigate and compare the safety and efficacy of two commonly used antiarrhythmic drugs, Dofetilide (DF) and Sotalol (SL), during inpatient drug initiation in patients with symptomatic atrial fibrillation (AF). Methods: We performed a single center retrospective study of consecutive patients, admitted for initiation of either DF or SL, for AF between 2012 and 2015. Rates of successful cardioversion, QT interval prolongation, adverse events and drug discontinuations were calculated and compared. A two-tailed p value less than 0.05 was considered statistically significant. Results: Of 378 patients, 298 (78.8%) received DF and 80 (21.2%) SL, mean age was 64 ± 11 years, 90% were Caucasians and 66% were males. Among the patients who remained in AF upon admission (DF: 215/298 (72%) vs. SL: 48/80 (60%)), no significant differences were noted in pharmacological cardioversion rates (DF: 125/215(58%) vs. SL: 30/48 (62.5%); p = 0.58). Baseline QTc was similar between the groups, with higher dose dependent QTc prolongation with DF (472.25± 31.3 vs. 458± 27.03; p = 0.008). There were no significant differences in the rates of adverse events such as bradycardia (7.4% vs. 11.3%; p = 0.26), Torsades de pointes (1.3% vs. 1.2%; p = 1.00), and drug discontinuation (9.0% vs. 5.0%; p = 0.47) between the two groups. Conclusion: In our large, single center experience, we found that the use of Dofetilide resulted in significantly higher QTc without differences in the rates of successful cardioversion, adverse events, and drug intolerance when compared to Sotalol in AF patients.

Introduction: Radiofrequency catheter ablation (RFCA), an effective treatment for atrial fibrillation (AF), is rarely complicated by severe pulmonary vein stenosis (PVS) requiring intervention. We sought to evaluate the safety of repeat RFCA in AF patients with moderate PVS after index RFCA. Hypothesis: We hypothesized, in patients with moderate PVS, repeat RFCA would not result in significant progression of PVS. Methods: We performed a retrospective, observational study of all patients who developed moderate PVS (decrease in the PV cross sectional area ≥50% but Results: Of a total of 2550 AF patients who underwent RFCA from 2011-2016, 165 (6.4%) developed moderate PVS of at least one PV. Mean age was 65 ± 11 years, with 130 (79%) males and 113 (68%) with paroxysmal AF. Right superior, right inferior, left superior and left inferior PVs were involved in 31%, 29%, 41%, and 20% of patients, respectively. Of these 165 patients, 78 (47%) underwent repeat CT scan (with or without redo ablation), and 48 (29%) underwent redo RFCA in the antrum of the involved PV. Mean times between CT1-CT2 and CT2-CT3 were 6 and 11 months, respectively. On repeat CT, 6 (8%) developed severe PVS of at least one PV. There was no statistical difference in the incidence of severe PV stenosis between those who underwent repeat ablation compared to those who did not (4.2 vs. 14.3 respectively; p = 0.185) Conclusions: Repeat RFCA for AF in patients with prior moderate PV stenosis appears to be safe with an acceptable risk (4.2%) of developing severe PV stenosis.

Background: Catheter ablation (CA) has an estimated success rate of 50-90% after first procedure for atrial tachycardia/fibrillation (AT/AF), supraventricular tachycardia (SVT), premature ventricular complexes (PVC) and ventricular tachycardia (VT). We studied if combination of induction agents including isoproterenol (ISO), Caffeine, Calcium Chloride (CC), Atropine and Phenylephrine (PE) is better than ISO alone to uncover additional arrhythmic triggers or substrates, where supplemental CA may potentially improve long term procedural success. Methods: This is an observational study including 132 consecutive patients [AT/AF (N=27), SVT (N=25), PVC (N=42), VT (N=38)] undergoing CA for symptomatic atrial and ventricular arrhythmias. We compared combination chemical induction protocol (COMBO) which included ISO (range 5-20mcg/min) + Caffeine (50-250 mg) +CC (1gm) ± PE (range 5 -10 mcg/kg) ±intravenous atropine (0.25 mg, one time) with ISO-only (5-20 mcg/min) infusion to assess for arrhythmia re-inducibility after performing standard CA. Results: There was no significant difference in baseline or procedural characteristics between both groups. COMBO group had significantly higher induction of stable clinical arrhythmia triggers and substrates in patients undergoing CA for AT/AF (53.3% vs. 8.3%, p=0.01), SVT (33% vs 0%, p=0.04), PVC (28.5% vs 0%, p=0.02) and VT (33.3% vs. 4.3%, p=0.02) when compared with ISO group which were additionally ablated. At 1-year follow up, COMBO group had significantly higher freedom from arrhythmias in AT/AF (20% vs. 41.6%, p=0.05), SVT (0% vs. 23%, p=0.04), PVC (4.7% vs. 43%, p=0.009) and VT ablation (26% vs. 61%, p=0.05) groups. Conclusion: COMBO induction protocol during CA may uncover additional triggers and arrhythmia substrates in patients with supraventricular and ventricular arrhythmias. COMBO directed supplemental CA may improve freedom from clinical arrhythmias on long term follow up.

Background: Epicardial access (EA) is increasingly used in various electrophysiological procedures with wide variation in EA success and complications. Methods: A comprehensive search was performed in PubMed, EBSCO and Google Scholar databases for studies reporting success and complications with EA. Meta-analysis was done using MedCalc software with random effects-model. Procedural success was defined as successful pericardial access. Pericardial tamponade was defined as pericardial effusion requiring drainage. Success and complications were adjusted and calculated per 100 procedures. Results: A total of 6 studies [retrospective - 5, prospective - 1] including 1,122 patients [large bore (LB) - 878, micropuncture (MP) - 219 and EpiAcces- 25 patients] undergoing EA for ventricular tachycardia ablation and Lariat procedure. Table 1,2 demonstrates rates of procedural success and complications of EA. Acute procedural success was 94.9% [95% CI (93.1 - 96.1)]. Pericardial tamponade, pericardial effusion, emergency heart surgery and RV puncture were seen in 1.7%, 2.8%, 0.7% and 6.5% respectively. Conclusion: EA is feasible with a 95% procedural success and acceptable rate of major complications. Use of MP needle and advancement in other EA technology will further improve procedure safety.

Introduction Limited data is available regarding the novel Reveal LinQ™ (LinQ) which is a new generation implantable loop recorders (ILRs). Methods We performed a prospective, observational study of all consecutive patients undergoing conventional (Reveal XT™; XT) and LinQ devices at our institution between January 2012 and December 2014. Results A total of 217 patients underwent ILR implantation. XT was implanted in 105 and LinQ in 112 patients. There were no significant differences in baseline characteristics between the two groups. LinQ implantation using the manufacturer's technique termed, "manufacturer's method" group had significantly higher incidence of pocket infection compared to XT (6/50, 12% vs 3/105, 3%, p=0.032). With modifications to the LinQ implantation technique (using a conventional scalpel and placing a suture when needed to the incision) termed "modified method" group, the rate of infection has decreased significantly compared to "manufacturer's method group" (0/62, 0% vs 6/50, 12%, p=0.004) (Table 3). In multivariate regression analysis, the only independent predictors of infection were younger age (OR 0.95; p=0.04), insertion of LinQ device (OR 30.02; p=0.006) and procedure time (OR 1.07; p=0.03). Conclusion In our single-center, prospective, observational study we found that with the current implantable techniques, the novel insertable LinQ device is associated with increased risk of complications.

Background Watchman and Lariat left atrial appendage (LAA) occlusion devices are associated with LAA leaks postdeployment. Objective The purpose of this study was to compare the incidence, characteristics, and clinical significance of these leaks. Methods We performed a multicenter prospective observational study of all patients who underwent LAA closure. Baseline, procedural, and imaging variables along with LAA occlusion rates at 30–90 days and 1-year postprocedure were compared. Results A total of 478 patients (219 with the Watchman device and 259 with the Lariat device) with successful implants were included. Patients in the Lariat group had a higher CHADS 2 (congestive heart failure, hypertension, age >74 years, diabetes, stroke) score and a larger left atrium and LAA. A total of 79 patients (17%) had a detectable leak at 1 year. More patients in the Watchman group had a leak compared with those in the Lariat group (46 [21%] vs 33 [14%]; P = .019). All the leaks were eccentric (edge effect) in the Watchman group and concentric (gunny sack effect) in the Lariat group. The size of the leak was larger in the Watchman group than in the Lariat group (3.10 ± 1.5 mm vs 2.15 ± 1.3 mm; P = .001). The Watchman group had 1 device embolization requiring surgery and 2 pericardial effusions requiring pericardiocentesis. In the Lariat group, 4 patients had cardiac tamponade requiring urgent surgical repair. Three patients in each group had a cerebrovascular accident and were not associated with device leaks. Conclusion The Lariat device is associated with a lower rate of leaks at 1 year as compared with the Watchman device, with no difference in rates of cerebrovascular accident. There was no correlation between the presence of residual leak and the occurrence of cerebrovascular accident.