Search

Introduction: Rheumatic heart disease with persistent atrial fibrillation (RHD‐AF) is associated with increased morbidity. However, there is no standardized approach for the maintenance of sinus rhythm (SR) in them. We aimed to determine the utility of a stepwise approach to achieve SR in RHD‐AF. Methods: Consecutive patients with RHD‐AF from July 2021 to August 2023 formed the study cohort. The stepwise approach included pharmacological rhythm control and/or electrical cardioversion (Central illustration). In patients with recurrence, additional options included AF ablation or pace and ablate strategy with conduction system pacing or biventricular pacing. Clinical improvement, NT‐proBNP, 6‐Minute Walk Test (6MWT), heart failure (HF) hospitalizations, and thromboembolic complications were documented during follow‐up. Results: Eighty‐three patients with RHD‐AF (mean age 56.13 ± 9.51 years, women 72.28%) were included. Utilizing this approach, 43 (51.81%) achieved and maintained SR during the study period of 11.04 ± 7.14 months. These patients had improved functional class, lower NT‐proBNP, better distance covered for 6MWT, and reduced HF hospitalizations. The duration of AF was shorter in patients who achieved SR, compared to those who remained in AF (3.15 ± 1.29 vs 6.93 ± 5.23, p = 0.041). Thirty‐five percent (29) maintained SR after a single cardioversion over the study period. Only one underwent AF ablation. Of the 24 who underwent pace and ablate strategy, atrial lead was implanted in 22 (hybrid approach), and 50% of these achieved and maintained SR. Among these 24, none had HF hospitalizations, but patients who maintained SR had further improvement in clinical and functional parameters. Conclusions: RHD‐AF patients who could achieve SR with a stepwise approach, had better clinical outcomes and lower HF hospitalizations. [ABSTRACT FROM AUTHOR]

Background: J waves may be augmented by coronary angiography (CAG) or intracoronary drug administration but the underlying mechanism is unknown. Purpose: The effect of intracoronary normal saline (NS) on J waves were investigated. Patients and methods: After the standard CAG using iopamidol (IopamiroR Inj), NS was injected into the right coronary artery in 10 patients with and eight patients without J waves at the baseline. The 12‐lead ECG was monitored, stored on a computer and retrieved later for measurement of the J wave amplitude before or during the coronary interventions. Results: J waves in leads II, III and aVF at baseline increased significantly in each lead during the right CAG and NS injection into the right coronary artery. The J wave changes were similar between the two interventions and distinct similar alterations were observed in the QRS complex. We postulated that the ischemic myocardium that was induced during CAG or intracoronary NS administration slowed the conduction velocity of depolarization in the perfusion territory and delayed the timing of J waves to appear. Then, the delayed appearance of J waves would be less opposed by electromotive force from other areas resulting in augmentation. Conclusion: J wave augmentation was observed during CAG and intracoronary NS administration. As a mechanism of augmentation, we postulated that contrast media and NS induce myocardial ischemia and delay the timing of J waves to a point of less opposition by electromotive force from other areas. Highlights: J wave augmentation has been reported during intracoronary injection of contrast media or drugs.The present study confirmed that normal saline alone was able to augment J waves.Mechanistically, coronary interventions using anoxic solutions can cause regional myocardial ischemia and reduce the conduction velocity of depolarization.Then, delayed J waves are less opposed by the electromotive force from remote areas which leads to augmentation.When a drug is diluted in normal saline and given intracoronarily, changes in J waves can be due to normal saline.The pathophysiological and clinical significance of J waves augmented during coronary interventions need to be established. [ABSTRACT FROM AUTHOR]

Background: Several studies have demonstrated that females have a higher risk of arrhythmia recurrence after pulmonary vein (PV) isolation for atrial fibrillation (AF). There are limited data on sex‐based differences in PV reconnection rates at repeat ablation. We aimed to investigate sex‐based differences in electrophysiological findings and atrial arrhythmia recurrence after repeat AF ablation Methods: We conducted a retrospective study of 161 consecutive patients (32% female, age 65 ± 10 years) who underwent repeat AF ablation after index PV isolation between 2010 and 2022. Demographics, procedural characteristics and follow‐up data were collected. Recurrent atrial tachycardia (AT)/AF was defined as any atrial arrhythmia ≥30 s in duration. Results: Compared to males, females tended to be older and had a significantly higher prevalence of prior valve surgery (10 vs. 2%; P =.03). At repeat ablation, PV reconnection was found in 119 (74%) patients. Males were more likely to have PV reconnection at repeat ablation compared to females (81 vs. 59%; P =.004). Excluding repeat PV isolation, there were no significant differences in adjunctive ablation strategies performed at repeat ablation between females and males. During follow‐up, there were no significant differences in freedom from AT/AF recurrence between females and males after repeat ablation (63 vs. 59% at 2 years, respectively; P =.48). Conclusions: After initial PV isolation, significantly fewer females have evidence of PV reconnection at the time of repeat ablation for recurrent AF. Despite this difference, long‐term freedom from AT/AF was similar between females and males after repeat ablation. [ABSTRACT FROM AUTHOR]

Objective: The presence of cannon A waves, the so called "frog sign", has traditionally been considered diagnostic of atrioventricular nodal re‐entrant tachycardia (AVNRT). Nevertheless, it has never been systematically evaluated. The aim of this study is to assess the independent diagnostic utility of cannon A waves in the differential diagnosis of supraventricular tachycardias (SVTs). Methods: We prospectively included 100 patients who underwent an electrophysiology (EP) study for SVT. The right jugular venous pulse was recorded during the study. In 61 patients, invasive central venous pressure (CVP) was registered as well. CVP increase is thought to be related with the timing between atria and ventricle depolarization; two groups were prespecified, the short VA interval tachycardias (including typical AVNRT and atrioventricular reciprocating tachycardia (AVRT) mediated by a septal accessory pathway) and the long VA interval tachycardias (including atypical AVNRT and AVRT mediated by a left free wall accessory pathway). Results: The relationship between cannon A waves and AVNRT did not reach the statistical significance (OR: 3.01; p =.058); On the other hand, it was clearly associated with the final diagnosis of a short VA interval tachycardia (OR: 10.21; p <.001). CVP increase showed an inversely proportional relationship with the VA interval during tachycardia (b = −.020; p <.001). CVP increase was larger in cases of AVNRT (4.0 mmHg vs. 1.2 mmHg; p <.001) and short VA interval tachycardias (3.9 mmHg vs. 1.2 mmHg; p <.001). Conclusion: The presence of cannon A waves is associated with the final diagnosis of short VA interval tachycardias. [ABSTRACT FROM AUTHOR]

Background: Conduction system pacing (CSP) is increasingly utilized to prevent and correct dyssynchrony. Barriers to CSP adoption include limited training, methodologic variability, laboratory slot allocation, and few data on learning curves. We report learning curves/clinical outcomes from a single experienced electrophysiologist who was new to CSP, and share gained insights. Methods: Retrospective analysis of all patients who underwent attempted CSP implantation (2016–2023). Patient characteristics, ECGs, echocardiograms, fluoroscopy/procedure times, lead data were recorded at implant and follow‐up. Results: CSP leads were implanted successfully in 167/191(87.4%) patients with a follow‐up of 278 ± 378 days. His‐bundle pacing (HBP = 59) and left‐bundle‐area pacing (LBAP = 108) had similar procedure/fluoroscopy times, QRS duration decreases, and ejection fraction improvements (all p > NS). Eight HBP lead revisions were required for high capture thresholds LBAP demonstrated lower pacing thresholds, higher lead impedances, and greater R‐wave amplitudes at implant and follow‐up. After 25 HBP cases, implant pacing thresholds, fluoroscopy, procedural times did not decrease. After 25 LBAP cases, there were significant decreases in all these parameters (p < 0.05). A separate analysis in LBAP patients with recorded Purkinje signals showed no differences in paced ECG characteristics between patients with pre‐ QRS Purkinje signals versus patients with Purkinje signals post‐QRS onset. Conclusions: Experienced implanters who are new to CSP can achieve steady‐state procedural/fluoroscopy times after a learning curve of 25 implants. LBAP showed lower capture thresholds and higher success rates. Adequate depth of lead deployment (as determined by published parameters) does not require Purkinje potential to be pre‐QRS. Operators new to CSP.can forego HBP and directly implement LBAP. [ABSTRACT FROM AUTHOR]

Background and Aims: Left bundle branch block (LBBB) is common after transcatheter aortic valve replacement (TAVR) and associated with a left or normal QRS axis. We aim to assess the QRS frontal plane axis shift changes during LBBB after TAVR and determine if the risk of procedure‐related high degree atrioventricular block (AVB) is affected by QRS axis shift changes. Methods and Results: In a retrospective single‐center study of 720 consecutive patients who underwent TAVR, 141 (19.6%) with normal baseline QRS duration developed a new LBBB after TAVR and constituted the study group. Most patients (59.6%) were females and the mean age of the cohort was 81.2 ± 6 years. Results: As compared with the baseline QRS axis before TAVR, the occurrence of LBBB was associated with a leftward QRS axis shift (by 40 ± 28.3°) in 73% of the study patients and a rightward (by 18.6 ± 19.4°) or no change in QRS axis in 25.6% and 1.4% of the study patients, respectively. A left QRS axis (−30°) was observed in 14.9% and 38.3% of the study patients before and after TAVR, respectively. The group of patients exhibiting a rightward or no QRS axis shift had a greater incidence of high degree AVB than the group of patients exhibiting a leftward QRS axis shift (18.4% vs. 6.8%, p =.056). Conclusion: Although post TAVR‐LBBB is associated with a leftward QRS axis shift in most patients, a non‐negligible proportion of patients (27%) exhibited a rightward or no QRS axis shift. The latter group tend to have a higher risk of developing high degree AVB. [ABSTRACT FROM AUTHOR]

Introduction: Recently, a new cryoballoon (CB) technology (POLARx; Boston Scientific) has come onto the market. Preliminary data have shown that its acute safety and efficacy are similar to those of the first‐generation CB. The aim of this study was to assess the medium‐term outcome of pulmonary vein isolation (PVI) with the POLARxTM CB in a large multicenter registry. Methods: We prospectively collected data on 125 consecutive patients with paroxysmal atrial fibrillation (AF) who underwent PVI by means of a novel CB system. Two cases of transient phrenic nerve palsy occurred, with full recovery in the 48h post procedure; no major procedure‐related adverse events were reported. During the 90‐day blanking period, 4 (3.2%) patients experienced an early recurrence. After the blanking period, over a mean follow‐up of 411 ± 62 days, 19 patients (15.2%) suffered an AF/atrial tachycardia (AT) recurrence. The 1‐year freedom from AF/AT recurrence was 86.4% (n = 17): 10 (8%) patients had an AF recurrence, 6 (4.8%) had an AT occurrence and 1 (0.8%) suffered both events. Patients with AF/AT recurrences had both a shorter deflation time and total deflation time. Moreover, CB ablations with measured TTI < 90 s and TTI < 60 s were more frequent in patients without AF/AT recurrence (88.5% and 77.4%, respectively) than in those who experienced at least one AF/AT recurrence (67.5% and 55.0%, p =.001 and p =.005, respectively). Conclusion: The novel POLARx cryo‐balloon system is safe and effective for PV isolation, displaying a 1‐year freedom from atrial arrhythmia recurrence of 86.4%, which is in line to that reported with AFA‐Pro CB or RF ablation. Clinical trial registration: Catheter Ablation of Arrhythmias with a High‐Density Mapping System in Real‐World Practice (CHARISMA). URL: http://clinicaltrials.gov/ Identifier: NCT03793998. Registration date: January 4, 2019. [ABSTRACT FROM AUTHOR]

Background: Conduction system pacing (CSP), including His‐bundle pacing (HBP) and left bundle branch area pacing (LBBAP), have been proposed as alternatives to biventricular pacing (BVP) in patients scheduled for ablate and pace (A&P) strategy. The aim of this study was to compare the clinical outcomes, including the rate and nature of device‐related complications, between BVP and CSP in a cohort of patients undergoing A&P. Methods: Prospective, multicenter, observational study, enrolling consecutive patients undergoing A&P. The risk of device‐related complications and of heart failure (HF) hospitalization was prospectively assessed. Results: A total of 373 patients (75.3 ± 8.7 years, 53.9% male, 68.9% with NYHA class ≥III) were enrolled: 263 with BVP, 68 with HBP, and 42 with LBBAP. Baseline characteristics of the three groups were similar. Compared to BVP and HBP, LBBAP was associated with the shortest mean procedural and fluoroscopy times and with the lowest acute capture thresholds (all p <.05). At 12‐month follow‐up LBBAP maintained the lowest capture thresholds and showed the longest estimated residual battery longevity (all p <.05). At 12‐months follow‐up the three study groups showed a similar risk of device‐related complications (5.7%, 4.4%, and 2.4% for BVP, HBP, and LBBAP, respectively; p =.650), and of HF hospitalization (2.7%, 1.5%, and 2.4% for BVP, HBP, and LBBAP, respectively; p =.850). Conclusions: In the setting of A&P, CSP is a feasible pacing modality, with a midterm safety profile comparable to BVP. LBBAP offers the advantage of reducing procedural times and obtaining lower and stable capture thresholds, with a positive impact on the device longevity. [ABSTRACT FROM AUTHOR]

Introduction: New and persistent left bundle branch block (NP‐LBBB) following Transcatheter Aortic Valve Replacement (TAVR) is an ongoing concern with incidence ranging from as low as 4% to up to 65% (varying for different types of valves). Such patients are at risk of developing high‐grade atrioventricular block (HAVB) warranting permanent pacemaker (PPM) implantation. However, currently, there are no consensus guidelines or large prospective studies to risk stratify these patients for safer discharge after TAVR. Objectives: To provide insight from a single center study on using modified electrophysiology (EP) study to risk stratify post‐TAVR patients to outpatient monitoring for low‐risk versus pacemaker implantation for high‐risk patients. Methods and Results: Between June 2020 and March 2023, all patients who underwent a TAVR procedure (324 patients) at our institution were screened for development of NP‐LBBB post‐operatively. Out of 26 patients who developed NP‐LBBB, after a pre‐specified period of observation, 18 patients were deemed eligible for a modified EP study to assess His‐Ventricular (HV) interval. 11 out of 18 patients (61.1%) had normal HV interval (HV < 55 ms). Three out of 18 patients (16.7%) had HV prolongation (55 ms < HV < 70 ms) without significant HV prolongation (defined as an increase in HV interval > 30%) with intra‐procedural procainamide challenge. Four out of 18 patients (22.2%) had significant HV prolongation (HV > 70 ms) warranting PPM implantation based on a multidisciplinary approach and shared decision‐making with the patients. Total of 50% of patients discharged with PPM (two out of four patients) were noted to be pacemaker dependent based on serial device interrogations. All patients who did not receive PPM were discharged with ambulatory monitoring with 30‐day event monitor and did not develop HAVB on serial follow‐up. Conclusion: Normal HV interval up to 55 ms on modified EP study after TAVR and development of NP‐LBBB can be utilized as a threshold for risk stratification to facilitate safe discharge. The optimal upper limit of HV interval threshold remains unclear in determining appropriate candidacy for PPM. [ABSTRACT FROM AUTHOR]

Background: Vasovagal syncope (VVS) is one of the most common causes of syncope. Traditional treatment has not achieved satisfactory results. The purpose of this study was to assess the feasibility and efficacy of selective anatomical catheter ablation of left atrial ganglionated plexus (GP) as a therapeutic strategy for the patients of symptomatic VVS. Methods: A total of 70 patients with at least once recurrent syncopal episode of VVS with a positive head‐up tilt test were enrolled. They were divided into GP ablation group and control group. Patients in GP ablation group received anatomical catheter ablation of left superior ganglionated plexus (LSGP) and right anterior ganglionated plexus (RAGP). Patients in the control group were guideline‐directed conventional therapy. The primary endpoint was VVS recurrences. The secondary endpoint was the recurrence of syncope and prodrome events. Results: There were no statistical differences in clinical characteristics between the ablation group (n = 35) and the control group (n = 35). Over a follow‐up of 12 months, the ablation group had significantly lower syncope recurrence compared with the control group (5.7% vs. 25.7%, p =.02), and the ablation group had significantly lower syncope and prodrome recurrence compared with the control group (11.4% vs. 51.4%, p <.001). In GP ablation, 88.6% of the patients showed significant vagal response during LSGP ablation, and 88.6% of the patients showed significantly increased heart rate during RAGP ablation. Conclusions: For patients with recurrent VVS, selective anatomical catheter ablation of LSGP and RAGP is superior to conventional therapy in reducing syncope recurrence. [ABSTRACT FROM AUTHOR]

Background: Although pulmonary vein isolation (PVI) remains the cornerstone of catheter ablation of atrial fibrillation (AF), several studies have illustrated clinical benefits associated with PVI with posterior wall isolation (PWI). Methods: This retrospective study investigated the outcomes of PVI alone versus PVI+PWI performed using the cryoballoon in patients with cardiac implantable electronic devices (CIEDs) and paroxysmal AF (PAF) or persistent AF (PersAF). Results: Acute PVI was achieved in all patients using cryoballoon ablation. Compared to PVI alone, PVI+PWI was associated with longer cryoablation, fluoroscopy, and total procedure times. Adjunct radiofrequency was required to complete PWI in 29/77 patients (37.7%). Adverse events were similar with PVI alone versus PVI+PWI. But at 24 ± 7 months of follow‐up, not only cryoballoon PVI+PWI was associated with improved freedom from recurrent AF (74.3% vs. 46.0%, P =.007) and all atrial tachyarrhythmias (71.4% vs. 38.1%, P =.001) in patients with PersAF, cryoballoon PVI+PWI also yielded greater freedom from AF (88.1% vs. 63.7%, P =.003) and all atrial tachyarrhythmias (83.3% vs. 60.8%, P =.008) in those with PAF. Additionally, PVI+PWI was associated with higher reductions in atrial tachyarrhythmia burden (97.9% vs. 91.6%, P <.001), need for cardioversion (5.2% vs. 23.6%, P <.001) and repeat catheter ablation (10.4% vs. 26.1%, P =.005), and a longer time‐to‐arrhythmia recurrence (16 ± 6 months vs. 8 ± 5 months, P <.001) in both PersAF and PAF patients. Conclusion: In CIED patients with PersAF or PAF, cryoballoon PVI+PWI is associated with a greater freedom from recurrent AF and atrial tachyarrhythmias, as compared to PVI alone during long‐term follow‐up. [ABSTRACT FROM AUTHOR]

Aims: Left bundle branch area pacing (LBBaP) upgrade can improve cardiac function and clinical outcomes in patients with pacing‐induced cardiomyopathy (PICM), but the specific value of LBBaP upgrade, especially compared with the cardiac function level before right ventricular pacing (RVP) in patients with PICM and non‐pacing‐induced cardiomyopathy‐related upgrade status (Non‐PICMUS) is still unknown. Methods: This study retrospectively enrolled 70 patients with LBBaP upgrade (38 patients with PICM and 32 patients with Non‐PICMUS). All upgrade patients experienced three stages: before RVP (Pre‐RVP), before LBBaP upgrade (Pre‐LBBaP), and after LBBaP upgrade (Post‐LBBaP). QRS duration (QRSd), lead parameters, echocardiographic indicators, and clinical outcomes evaluation were recorded at multiple time points. Results: At the follow‐up of 12 months, for PICM patients, left ventricular ejection fraction (LVEF) significantly increased from 36.6% ± 7.2% to 51.3% ± 8.7% Post‐LBBaP (p <.001), and left ventricular end‐diastolic diameter (LVEDD) significantly decreased from 61.5 ± 6.4 mm to 55.2 ± 6.5 mm Post‐LBBaP (p <.001), but they both failed to restore the level Pre‐RVP (both p <.001). For PICM patients, New York Heart Association (NYHA) classification, the number of moderate‐to‐severe heart failure (NYHA III–IV), and diuretics using rate after the LBBaP upgrade also could not restore to the level Pre‐RVP (all p <.001). At the follow‐up of 12 months, Non‐PICMUS patients after the LBBaP upgrade had no significant improvement in LVEF, LVEDD, and NYHA classification (all p >.05). Conclusion: LBBaP upgrade effectively improved the cardiac function and clinical outcomes in PICM patients, but its effectiveness seemed to be limited as the deteriorated cardiac function cannot be completely reversed. For Non‐PICMUS patients, the cardiac function and clinical outcomes Post‐LBBaP had no significant improvement. [ABSTRACT FROM AUTHOR]

Background: The percutaneous extraction of endovascular cardiostimulation and defibrillation leads is the most frequent technique nowadays. The tools used today must guarantee the success of the procedure, with the minimum of complications. Our objective was to analyze the safety and efficacy of lead extraction using the Evolution mechanical dissection tool (Cook Medical, USA). Methods: A retrospective study was carried out in a total of 826 consecutive patients from October 2009 to December 2018 who underwent the procedure with the Evolution mechanical dissection tool. Preoperative study included complete blood tests, echocardiogram, and chest X‐ray. The procedures were performed in the operating room, under general anesthesia and echocardiographic control. Results: A total of 1227 leads were extracted with a mean chronicity of 10.3 ± 5.1 years. Clinical success (CS) rate was 99.7%. A total of 16 (1.9%) complications occurred, 2 (0.24%) were major complications and 14 (1.7%) were minor complications. There was no operative mortality. There was no statistically significant relationship between implant chamber and complete efficacy. The complete extraction was achieved in all left ventricular leads, in 762 of 774 (98.45%) of right ventricular lead removal, and in 330 of 334 (98.8%) of right atrial leads (p =.31). Conclusion: In our experience, percutaneous extraction of intravenous leads via the use of the Evolution tool (Cook Medical, USA), is a very effective and safe technique that offers low morbidity and mortality. [ABSTRACT FROM AUTHOR]

Background: Implantable cardioverter defibrillators (ICDs) offer effective therapy for the prevention of sudden cardiac death (SCD) due to ventricular arrhythmias. However, inappropriate shocks have detrimental effects on survival and quality of life. The addition of hemodynamic monitoring may be useful in discriminating clinically important ventricular arrhythmias. Objective: In this study, we assess the ability of laser Doppler flowmetry to assess the hemodynamic effect of paced atrial and ventricular arrhythmias using mean arterial blood pressure as the reference. Methods: In this acute human study in patients undergoing an elective electrophysiological study, laser Doppler flowmetry, arterial blood pressure, and surface ECG were acquired during high‐rate atrial and ventricular pacing to simulate supraventricular and ventricular tachycardias. Results: Arterial blood pressure and laser Doppler flow signals correlated well during atrial and ventricular pacing (rho = 0.694, p <.001). The hemodynamic impairment detected by both methods was greater during ventricular pacing than atrial pacing (–1.0% vs. 19.0%, p <.001). Laser Doppler flowmetry performed better than rate alone to identify hemodynamic impairments. Conclusion: In this acute study, laser Doppler flowmetry tissue perfusion served as a good surrogate measure for arterial pressure, which could be incorporated into future ICDs. [ABSTRACT FROM AUTHOR]

Background: Although much has been discussed about the early recurrence of atrial fibrillation (ERAF) after cryoballoon ablation (CBA), the clinical impact of very early recurrence of atrial fibrillation (VERAF) after CBA remains unclear. This study aimed to investigate the impact of VERAF after CBA. Methods: We enrolled 236 consecutive patients who underwent an initial CBA for paroxysmal atrial fibrillation between February 2017 and December 2020 in our hospital. These patients were categorized into three groups: VERAF group who experienced an initial recurrence of atrial tachyarrhythmia within 48 h after CBA, late‐ERAF (LERAF) group who experienced an initial recurrence of atrial tachyarrhythmia between 48 h and 3 months after CBA, and non‐ERAF (NERAF) group who did not experience a recurrence of atrial tachyarrhythmia within 3 months after CBA. We investigated the late recurrence of AF (LRAF, defined as recurrence of atrial tachyarrhythmia more than 3 months after CBA), and the incidence of non‐pulmonary vein (PV) triggers in the patients who experienced a repeat ablation procedure due to LRAF. Results: VERAF group had a higher incidence of freedom from LRAF than LERAF group (p = 0.032) and a lower incidence of freedom from LRAF than NERAF group (p = 0.002). Moreover, VERAF group had the highest incidence of non‐PV triggers at repeat ablation procedure among the three groups (p = 0.003). Conclusions: While ERAF was a predictor of LRAF, VERAF was less related to LRAF among the patients with ERAF after CBA. Furthermore, VERAF might be associated with non‐PV triggers. [ABSTRACT FROM AUTHOR]

Background: Cardiac contractility modulation (CCM), being reserved for patients with symptomatic chronic heart failure (HF) and narrow QRS complex under guideline directed medical therapy, can recover initially reduced left ventricular ejection fraction (LVEF); however, the influence of pre‐implantation LVEF on long‐term outcomes is not fully understood. This study aimed to compare the effects of lower and higher preimplantation LVEF on long‐term outcomes in CCM‐therapy. Methods: One‐hundred seventy‐two patients from our single‐centre registry were retrospectively included (2002–2019). Follow‐up data were collected up to 5 years after implantation. Patients were divided into Group 1 (baseline LVEF≤ 30%) and Group 2 (≥ 31%). Both groups were compared based on differences in survival, echocardiographic‐ and clinical parameters including LVEF, tricuspid annular plane systolic excursion (TAPSE), NYHA class or Minnesota living with heart failure questionnaire‐score (MLWHFQ). Results: 11% of the patients did have a LVEF ≥31%. Mean LVEF ± SD for both groups were 21.98 ± 5.4 versus 35.2 ± 3.7%, respectively. MLWHFQ (47 ± 21.2 vs. 42±21.4) and mean peak oxygen consumption (VO2, 13.6 ± 4.1 vs. 12.7 ± 2.8 ml/kg/min) were comparable between both groups. LVEF‐grouping did not influence survival. Lower baseline LVEF resulted in significantly better recovery of echocardiographic parameters such as LVEF and TAPSE. Irrespective from baseline LVEF, both groups showed nearly comparable improvements for clinical parameters like NYHA‐class and MLWHFQ. Conclusion: Long‐term biventricular systolic recovery potential in CCM‐therapy might be better for preimplantation LVEF values ≤30%, whereas clinical parameters such as NYHA‐class can improve irrespective from baseline LVEF. [ABSTRACT FROM AUTHOR]

Background: Pro‐inflammatory pathways play an important role in the follow‐ups of patients with intracardiac defibrillators (ICDs) for heart failure (HF) reduced with ejection fraction (HFrEF). A newly defined index ‐ the systemic immune‐inflammation index (SII)—has recently been reported to have prognostic value in patients with cardiovascular disease. This study's aim is to evaluate the SII value regarding its association with long‐term mortality and appropriate ICD therapy during a 10‐year follow‐up. Methods: This retrospective study included 1011 patients with ICD for HFrEF. The SII was calculated as the neutrophil—to—lymphocyte ratio × total platelet count in the peripheral blood. The study population was divided into two groups according to the SII's optimal cut‐off value to predict long‐term mortality. The long‐term prognostic impact of SII on these patients was evaluated regarding mortality and appropriate ICD therapy. Results: The patients with a higher SII (≥1119) had significantly higher long‐term mortality and appropriate ICD therapy rates. After adjustment for all confounding factors, the long‐term mortality rate was 5.1 for a higher SII. (95% CI: 2.9–8.1). The long‐term appropriate ICD therapy rate was 2.0 for a higher SII (95% CI: 1.4–3.0). Conclusion: SII may be an independent predictive marker for both long‐term mortality and appropriate ICD therapy in patients with HFrEF. [ABSTRACT FROM AUTHOR]

Introduction: We previously reported the clinical benefits of radiofrequency catheter ablation (RFCA) of premature ventricular contractions (PVCs) from the right ventricular outflow tract or near the His‐bundle, which can often deteriorate the clinical status. PVCs from the mitral valve (MA‐PVCs) also often deteriorate the patients' clinical status. This study aimed to evaluate the effect of ablating MA‐PVCs with RFCA from a trans‐interatrial septal approach on the clinical status in symptomatic patients with frequent MA‐PVCs without structural heart disease. Methods: The frequency of PVCs per the total heart beats by 24‐hours Holter monitoring and New York Heart Association (NYHA) functional class in 22 patients with MA‐PVCs were evaluated before and 6 months after RFCA. Results: Procedural success was achieved in 20 (91%) of 22 patients. Of the 22 patients, in 15 (68%) and 1 (5%) patient, a successful RFCA on the left ventricular side of the MA using the trans‐interatrial septal approach and trans‐coronary sinus approach was achieved. Interestingly, in four (18%) patients, a successful RFCA on the left atrial (LA) side of the MA using a trans‐interatrial septal approach was achieved. Ablating MA‐PVCs readily improved the NYHA functional class compared to that before. A ≥0.62 peak deflection index and ≤30 years old may be one of the important predictors of successfully ablated MA‐PVCs from the LA side of the MA. Conclusions: RFCA produces clinical benefits in patients with MA‐PVCs. Further, it may be necessary to initially consider a trans‐interatrial septal approach to ablate these PVCs. [ABSTRACT FROM AUTHOR]

Background: Endocardial pacing may be beneficial in patients who fail to improve following conventional epicardial cardiac resynchronization therapy (CRT). The potential to pace anywhere inside the left ventricle thus avoiding myocardial scar and targeting the latest activating segments may be particularly important. The WiSE‐CRT system (EBR systems, Sunnyvale, CA) reliably produces wireless, endocardial left ventricular (LV) pacing. The purpose of this analysis was to determine whether this system improved symptoms or led to LV remodeling in patients who were nonresponders to conventional CRT. Method: An international, multicenter registry of patients who were nonresponders to conventional CRT and underwent implantation with the WiSE‐CRT system was collected. Results: Twenty‐two patients were included; 20 patients underwent successful implantation with confirmation of endocardial biventricular pacing and in 2 patients, there was a failure of electrode capture. Eighteen patients proceeded to 6‐month follow‐up; endocardial pacing resulted in a significant reduction in QRS duration compared with intrinsic QRS duration (26.6 ± 24.4 ms; P =.002) and improvement in left ventricular ejection fraction (LVEF) (4.7 ± 7.9%; P =.021). The mean reduction in left ventricular end‐diastolic volume was 8.3 ± 42.3 cm3 (P =.458) and left ventricular end‐systolic volume (LVESV) was 13.1 ± 44.3 cm3 (P =.271), which were statistically nonsignificant. Overall, 55.6% of patients had improvement in their clinical composite score and 66.7% had a reduction in LVESV ≥15% and/or absolute improvement in LVEF ≥5%. Conclusion: Nonresponders to conventional CRT have few remaining treatment options. We have shown in this high‐risk patient group that the WiSE‐CRT system results in improvement in their clinical composite scores and leads to LV remodeling. [ABSTRACT FROM AUTHOR]

Background: Ablation of slow‐fast atrioventricular nodal reentrant tachycardia (S/F‐AVNRT) is occasionally refractory. We hypothesized that the site of ablation for curing S/F‐AVNRT can be screened by simple differential atrial entrainment pacing (EP) from the high right atrium (HRA) and proximal coronary sinus (prox‐CS). Methods: We enrolled 43 patients with S/F‐AVNRT who underwent successful differential atrial EP followed by successful ablation of slow pathway (SP) using step‐wise approach, and compared the atrio‐His (A‐H) interval at the recording of His bundle immediately after EP from the HRA [A‐H(HRA)], with the interval between atrial deflection at the prox‐CS and His bundle electrogram after EP at an identical cycle length from the prox‐CS [A‐H (prox‐CS)]. Results: A typical A‐H(CS) shorter than A‐H(HRA), consistent with typical SP conduction, was observed in 39 patients (91%), and an atypical A‐H(HRA) shorter than A‐H(CS) was observed in 4 patients (9%). Successful ablation was obtained at the posteroseptum/midseptum in 32/7 patients with typical responses but only at the midseptum in all 4 patients with atypical responses (P =.0027). The atypical responses predicted a necessity for ablation at the midseptum, with positive and negative predictive values of 100% and 82%, respectively. The mechanism of an atypical response remains unclear but may involve an anatomical variation of Koch's triangle and/or the participation of a variant of the SP, including the superior SP, over which retrograde conduction was observed more frequently in patients with atypical responses (P =.0013). Conclusions: Differential atrial EP predicts the ablation site for successfully curing S/F‐AVNRT. [ABSTRACT FROM AUTHOR]

Background After around 10% of heart transplant patients require pacemaker implantation. The bradyarrhythmias causing pacemaker requirement include sinus node dysfunction (SND) and atrioventricular block (AVB). This study sought to define clinical predictors for pacemaker requirement as well as identify differences in the patient groups developing SND and AVB. Methods Our operative database was used to collect retrospective recipient, donor, and operative data of all patients receiving orthotopic heart transplants between 1981 and 2016. Results In the 35-year period 1,179 transplants were performed (mean recipient age 45.5 ± 0.5 years, 20.4% female, 90.6% biatrial technique) with bradyarrhythmias requiring pacemaker implantation developing in 135 patients (11.5%). Independent risk factors were prolonged operative time 340 minutes versus 313 minutes (P = 0.027) and a biatrial anastomosis (P = 0.036). Ischemia time, cardiopulmonary bypass time, aortic cross clamp time, and reperfusion time all had no significant effect on pacemaker implantation rates. Similarly, whether the transplant was a reoperation, a retransplant, or performed after primary assist implantation had no effects on pacemaker implantation rates. There was no survival difference between the paced and nonpaced groups. The donor age was higher in the patients who developed AVB as the indication for pacemaker implantation (43 vs 34 years, P = 0.031). Patients with AVB had longer aortic cross clamp times and developed the arrhythmia later than those who developed SND. Conclusions Use of the bicaval instead of the biatrial technique and shortened operative times should reduce pacemaker requirement after heart transplantation. Survival is not affected by this complication. [ABSTRACT FROM AUTHOR]

Background Left ventricular end-systolic volume (LVESV) changes at 6 months and clinical status are useful for assessing responses to cardiac resynchronization therapy (CRT). Regression of the LVESV following CRT has not been described beyond 6 months. This study aimed to assess the proportion, predictors, and clinical outcomes of responders whose LVESVs had regressed. Methods We retrospectively analyzed 104 consecutive CRT patients. A responder was defined as a patient with a relative reduction in the LVESV ≥15% at 6 months after CRT. Fifty-six responders participated in this study. A transient responder was defined as a responder without a relative reduction in the LVESV ≥15% at 2 years after CRT or who died of cardiac events during the 24-month follow-up period. Results Of the 56 responders, 16 (29%) were transient responders. Multivariable logistic regression analysis showed that chronic atrial fibrillation (odds ratio [OR] = 19.2, 95% confidence interval [CI] [1.93, 190], P = 0.012) and amiodarone usage (OR = 60.9, 95% CI [4.18, 886], P = 0.003) were independent predictors of transient responses. Hospitalizations for heart failure were significantly higher among the transient responders than among the lasting responders during a mean follow-up period of 7.6 years (log-rank P < 0.001), and all-cause mortality tended to be higher among the transient responders (log-rank P = 0.093). Conclusions One-third of the responders were transient responders at 2 years after CRT, and their long-term prognoses were poor. Careful attention should be paid to maintain the reduction in LVESV especially in patients with chronic AF. [ABSTRACT FROM AUTHOR]

Background The role of J-waves in the pathogenesis of ventricular fibrillation (VF) occurring in structurally normal hearts is important. Methods We evaluated 127 patients who received an implantable cardioverter-defibrillator (ICD) for Brugada syndrome (BS, n = 53), early repolarization syndrome (ERS, n = 24), and patients with unknown or deferred diagnosis (n = 50). Electrocardiography (ECG), clinical characteristics, and ICD data were analyzed. Results J-waves were found in 27/50 patients with VF of unknown/deferred diagnosis. The J-waves were reminiscent of those seen in BS or ERS, and this subgroup of patients was termed variants of ERS and BS (VEB). In 12 VEB patients, the J/ST/T-wave morphology was coved, although amplitudes were <0.2 mV. In 15 patients, noncoved-type J/ST/T-waves were present in the right precordial leads. In the remaining 23 patients, no J-waves were identified. VEB patients exhibited clinical characteristics similar to those of BS and ERS patients. Phenotypic transition and overlap were observed among patients with BS, ERS, and VEB. Twelve patients with BS had background inferolateral ER, while five ERS patients showed prominent right precordial J-waves. Patients with this transient phenotype overlap showed a significantly lower shock-free survival than the rest of the study patients. Conclusions VEB patients demonstrate ECG phenotype similar to but distinct from those of BS and ERS. The spectral nature of J-wave morphology/distribution and phenotypic transition/overlap suggest a common pathophysiologic background in patients with VEB, BS, and ERS. Prognostic implication of these ECG variations requires further investigation. [ABSTRACT FROM AUTHOR]

Background Hypothermia is associated with the development of J waves. However, little is known about the impact of these electrocardiogram (ECG) findings on the development of ventricular arrhythmias and patient outcomes during therapeutic hypothermia (TH) postresuscitation from out-of-hospital cardiac arrest (OHCA). We investigated the prevalence of J waves in OHCA patients prior to and during TH. Additionally, we explored the incidence of atrial and ventricular arrhythmias and in-hospital mortality for patients with and without J waves either at baseline, during TH, or both. Methods We conducted a retrospective analysis of patients who suffered OHCA and underwent TH (goal temperature of 32-34°C). Fifty-nine patients were stratified dependent upon the presence of or the development of J waves on surface ECGs. Descriptive analysis and logistic regression modeling were used to assess the population differences and mortality, respectively, between patients who developed J waves during TH and those who did not. Results There was no difference in the development of in-hospital atrial or ventricular arrhythmias between patients with J waves present during TH (16%) and those without (17.6%, P = 0.834). Compared to patients without J waves at baseline and during TH, those with J waves present both at baseline and during TH had significantly worse survival (hazard ratio = 12.42, P = 0.046). Conclusions While J waves are common ECG findings during TH in patients resuscitated from OHCA, our study demonstrated an increase in mortality for patients with J waves present both at baseline and during TH. [ABSTRACT FROM AUTHOR]

Background Weight loss has been associated with adverse outcomes among heart failure (HF) patients, including those receiving cardiac resynchronization therapy with defibrillator (CRT-D). The effect of significant weight change on inappropriate implantable cardioverter-defibrillator (ICD) therapy among CRT-D patients is not well understood. Methods We evaluated the impact of significant weight change at 1 year on subsequent inappropriate ICD therapy during follow-up among 993 CRT-D patients enrolled in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy. Patients were divided into three subgroups based on weight change at 1 year after enrollment: weight loss (weight loss ≥ 5%), weight gain (weight gain ≥ 5%), and stable weight (weight loss and weight gain < 5%). The primary end point was inappropriate ICD therapy. Secondary end point included inappropriate ICD therapy related to supraventricular arrhythmias (SVAs). Results There were 102 (10.3%) patients who experienced weight loss, 689 (69.4%) whose weight was stable, and 202 (20.3%) who gained weight at 1 year. Patients with weight loss had increased risk of subsequent inappropriate ICD therapy relative to patients with stable weight (hazard ratio [HR] = 2.35, 95% confidence interval [CI]: 1.39-3.98, P = 0.001) or weight gain (HR = 2.27, 95% CI: 1.18-4.38, P = 0.014). Furthermore, patients losing weight were at greater risk of subsequent inappropriate ICD therapy related to SVAs when compared to patients with stable weight (HR = 2.16, 95% CI: 1.18-3.95, P = 0.013) or weight gain (HR = 2.02, 95% CI: 0.95-4.29, P = 0.068). Conclusion In mild HF patients receiving CRT-D, significant weight loss at 1 year is associated with increased risk of subsequent inappropriate ICD therapy, including risk related to SVAs. [ABSTRACT FROM AUTHOR]

Background Patients with congenital heart defects (CHD) often present more challenges to pacing therapy due to anatomy than those without CHD. The lumenless, 4.1Fr diameter M3830 pacing lead (Medtronic, Inc., Minneapolis, MN, USA), approved for use in 2005, has, to date, reported to have excellent short-term (<6 years) lead performance. Unfortunately, very long-term performance is unknown, especially among CHD patients and with implants at alternate pacing (AP) sites. This study reports a 10-year clinical experience with the M3830 lead. Methods Records of patients who received the M3830 lead were reviewed: patient demographics, implant techniques and locations, sensing and pacing characteristics, impedances (Imp), and any complications at implant and follow-up. Results From 2005 to 2015, 141 patients (ages 2-50, mean 20.1 years, 57% males) received 212 leads: atrial 115; ventricle 97. CHD was present in 62% of patients. Leads were inserted at AP sites in 96% of patients. Postimplant follow-up was from 3 months to 10 years (mean 56.3 months). Comparative implant versus follow-up values (mean ± standard deviation) were available on 196 leads (92.5%), showing persistently low (<1 v @ 0.4-0.5 ms) pacing thresholds (P = 0.57). Sensing was also comparable (atrial leads, P = 0.41; ventricular leads, P = 0.9). Impedances differed (P < 0.05) but remained within the normal range. Two A leads became dislodged and one was repositioned while two other leads (1 A, 1 V) were extracted. There are no differences observed in the pacing characteristics between the CHD and non-CHD groups on follow-up. Conclusions The 4.1Fr lumenless pacing lead shows ease of implant regardless of CHD or AP site, excellent very long-term (10 years) stability, and performance indices with a very low rate of complications. [ABSTRACT FROM AUTHOR]

Background Cryoballoon ablation (CBA) for paroxysmal atrial fibrillation (pAF) can be performed under general anesthesia (GA) or moderate sedation (MS). Our objective was to compare the effectiveness, safety, procedure duration, and time spent in the electrophysiology (EP) laboratory for CBA performed under GA and MS. Methods Patients undergoing a first CBA for pAF were identified. Patients received either GA administered by an anesthesiologist or MS with midazolam and fentanyl administered by EP laboratory staff. Total time in laboratory (sum of procedure and nonprocedure time); fluoroscopy time; freedom from documented AF, atrial flutter, and atrial tachycardia (FFAF); acute pulmonary vein isolation (PVI) rate; and 30-day complication rate were assessed. Results A total of 55 patients received GA and 119 patients received MS. PVI success rate was 100% in GA and 98.1% in MS (P = 0.04). Total laboratory time was longer for GA (280.4 ± 54.1 minutes vs 245.5 ± 54.7 minutes; P < 0.001), related to longer nonprocedure time (92.2 ± 28.8 minutes GA vs 71.0 ± 30.0 minutes MS; P < 0.001), but not procedure time (188.3 ± 49.3 minutes GA vs 174.5 ± 50.2 minutes MS; P = 0.09). FFAF was not significantly different over a median follow-up duration of 0.9 (interquartile range 0.4-1.9) years (61.8% GA vs 63.0% MS; log-rank P = 0.90). There was no significant difference in complication rate. Conclusion Compared to GA, MS during CBA for pAF was independently associated with shorter total EP laboratory time without compromising FFAF or complication rates. [ABSTRACT FROM AUTHOR]

Background We investigated computed tomography (CT) angiography (CTA) in assessment of left atrial appendage (LAA) stasis and thrombus in preprocedural evaluation for atrial fibrillation (AF) ablation in a large community cohort. Methods and Results We reviewed CTA and transesophageal echocardiographic images obtained in 861 consecutive patients with a history of AF undergoing same-day CTA and transesophageal echocardiogram (TEE) before AF ablation at a single hospital (2006-2013). CTA findings of LAA filling defects from acquisitions without electrocardiogram gating were compared to TEE features of LAA stasis (grade 0-4) and thrombus. Stasis grade 0 or 1 by TEE in the absence of thrombus was defined as a negative result. In addition, LAA peak flow velocity was assessed by TEE. Average age was 61 ± 10 years and 75% were male. On CTA, 161 patients (19%) had LAA filling defects on CTA and 21 had ≥grade 2 stasis on TEE, including two with thrombus, resulting in a positive predictive value of only 13%. However, among 670 CTA-negative patients, 669 (99%) were negative for thrombus or stasis by TEE with one false-negative CTA in a patient with grade 2 stasis by TEE but no thrombus, yielding a negative predictive value of 99.9%. Slow LAA Doppler flow velocity was the most important determinant of false-positive CTA results in multivariate analysis (P < 0.0001) Conclusion LAA filling defects on CT are associated with slow LAA flow velocity. AF patients without LAA filing defects on CT are free of significant stasis and thrombus on TEE. It may be possible to eliminate TEE in up to 80% of AF ablation patients based on negative CTA findings. [ABSTRACT FROM AUTHOR]

Background Atrial fibrillation (AF) is the most common sustained arrhythmia and is independently associated with increased risk of stroke and death. Although the exact mechanisms of AF are not completely elucidated, a large number of evidences demonstrate that autoimmunity may play an important role in the initiation, the progression, and the maintenance of AF. In this study, we aimed to compare anti-β1-adrenergic receptor autoantibody (anti-β1-R) and anti-M2-muscarinic receptor autoantibody (anti-M2-R) levels between nonvalvular AF patients and healthy control subjects. Methods The levels of serum anti-β1-R, antinuclear antibodies, and anti-M2-R were measured in both groups by enzyme-linked immunosorbent assay (ELISA). High-sensitivity C-reactive protein (hs-CRP) and interleukin (IL)-6 concentration were measured, respectively, by immunoturbidimetry and chemiluminescence. Results Anti-β1-R and anti-M2-R levels were significantly higher in patients with nonvalvular AF than in healthy controls (anti-β1-R 221.11 [132.38-291.69] ng/mL vs 198.14 [125.70-278.40] ng/mL, P < 0.01; anti-M2-R 271.81 [144.99-378.20] ng/mL vs 235.01 [121.53-358.99] ng/mL, P < 0.01). Compared with the control group, the serum levels of IL-6 and hs-CRP were higher in the nonvalvular AF group (IL-6 19.65 ± 5.6 pg/mL vs 6.79 ± 1.09 pg/mL, hs-CRP 6.03 ± 1.35 mg/L vs 2.73 ± 0.63 mg/L, P < 0.05). Antinuclear antibody (ANA) levels were similar between two groups (ANA 10.55 [1.86-271.8] U/mL vs 10.49 [1.303-161.7] U/mL, P > 0.05). The baseline value of serum anti-β1-R (odds ratio [OR]: 13.176, P < 0.001), anti-M2-R (OR: 4.41, P < 0.001), IL-6 (OR: 6.126, P < 0.05) levels, and left atrial diameter (OR: 5.781, P < 0.05) were independent predictors of nonvalvular AF by multivariable analyses. Conclusion We found a significant association between circulating serum anti-β1-R, anti-M2-R, IL-6 levels, and nonvalvular AF. We presume that the autoimmunity and inflammation might take part in electrical remodeling and structural remodeling of left atrium. [ABSTRACT FROM AUTHOR]

Background Characteristics and outcomes of concurrently diagnosed new rapid atrial fibrillation (AF) or atrial flutter (AFL) and new heart failure with reduced left ventricular ejection fraction (LVEF) are not well described. Methods A retrospective cohort study of subjects referred for expedited transesophageal echocardiography-guided rhythm-control strategies for concurrent new rapid AF/AFL and new LVEF ≤ 40% diagnosed during the same admission was analyzed. Results Twenty-five subjects (median age 57 years; 96% male; 96% Caucasian; median CHA2DS2-VASc = 2) presented with new AF (n = 18) or AFL (n = 7) with rapid ventricular rate (median 135 beats/min) and new reduced LVEF (median 27%; range, 10-37.5%). Seven (28%) subjects had left atrial appendage thrombi (LAAT) and five (20%) subjects had heavy or binge alcohol use. Baseline characteristics were similar between those with and without LAAT. Thirteen subjects with AF and without LAAT underwent direct-current cardioversion (DCCV) and 10 (77%) had AF recurrence within 90 days. Improvement of long-term LVEF to >40% was comparable for subjects with and without initial LAAT (83% vs 94%; P = 0.46). Three of four subjects who received primary prophylaxis implantable cardioverter-defibrillators improved their LVEF to >35% after sinus rhythm maintenance. The median long-term follow-up time was 3.0 years. Conclusions Subjects with concurrently diagnosed new rapid AF/AFL and new reduced LVEF are characterized by a high prevalence of LAAT and significant alcohol use. AF subjects without initial LAAT who underwent DCCV had a high 90-day AF recurrence rate. The presence of LAAT did not have a prognosticative effect on eventual LVEF improvement, which was observed in almost all subjects. [ABSTRACT FROM AUTHOR]

Background Little systematic evidence is available on potential gender differences in patients with an implantable cardioverter defibrillator (ICD) from a real-world cohort. We designed the DEFIB-WOMEN (The Utilization of Implantable Cardioverter DEFIBrillator Therapy in the Treatment of Heart Disease: Clinical and Psychological outcomes in WOMEN) study to examine gender differences on (1) patient-reported outcomes (PROs), (2) procedure- and device-related complications, and (3) ventricular tachyarrhythmia and mortality. This presents the study design and baseline characteristics of the cohort. Methods DEFIB-WOMEN is a national, multicenter, prospective, observational study. First-time implanted patients are asked to complete PROs at several time points. Information on baseline and follow-up characteristics are captured from patients' medical records, purpose-designed questions, and the Danish national registers. The DEFIB-WOMEN cohort is composed of 1,790 (19% women; 343/1,790) patients implanted between June 2010 and April 2013. Results Women and men differed on several demographic and clinical baseline characteristics, including on the prescription of β-blockers, statins, angiotensin-converting enzyme inhibitors, and psychotropic agents. Although women generally had a healthier clinical profile, they reported significantly more symptoms of anxiety and depression and ICD concerns (fear of shock) as compared to men. These differences were not only statistically significant but also clinically relevant, with the magnitude of the differences in anxiety and ICD concerns being 0.44 and 0.42, respectively, as indicated by Cohen's effect size index. Conclusions These preliminary results indicate that women with an ICD experience particularly more anxiety and ICD concerns as compared to men at the time of implant. Future results of DEFIB-WOMEN will show whether these gender differences persist and whether there are also gender differences in complications and survival. [ABSTRACT FROM AUTHOR]

Background Despite concerns about complications with the implantable cardioverter defibrillator (ICD), it is effective for the prevention of sudden cardiac death (SCD). We aimed to analyze our midterm experience with ICD in children and young adults. Methods This retrospective study included patients who were implanted with an ICD between 2001 and 2014. Demographic characteristics, clinical information, shock features, and complications for all patients with ICD were analyzed. The study population was divided into two groups: early-era patients implanted before 2008, and late-era patients implanted after 2008. Results Sixty-nine patients (median age: 12 years, median follow-up: 52 months) were implanted with an ICD. Diagnostic categories were channelopathy (56.6%), cardiomyopathy (36.2%), congenital heart disease (5.8%), and other (1.4%). We performed implantation for primary prevention in 66.6% (39.3% in early-era patients and 85.4% in late-era patients). Thirty-one (44.9%) received 139 appropriate shocks (66% of total shocks) while 14 (20.2%) received 71 inappropriate shocks. However, there was no statistically significant difference in the use of appropriate shocks in the primary (66.7%) versus the secondary (72.2%) prevention groups. The incidence of appropriate and inappropriate shock was 66.7% and 33.3% in the primary prevention group, and 72.2% and 27.8% in the secondary prevention group, respectively. Two patients died, although only one death was the result of a lead problem. Conclusions Although lead integrity problems, inappropriate shocks, and infections are significant issues, ICD therapy appears to be a safe, effective, and necessary option for the prevention of SCD in both children and young adults. [ABSTRACT FROM AUTHOR]

Background We aimed to identify the predictors of clinical outcomes after circumferential pulmonary vein isolation (CPVI) without any substrate modification for longstanding persistent atrial fibrillation (LSP-AF). Methods This study retrospectively analyzed 70 consecutive LSP-AF patients who underwent an initial CPVI and were followed-up for more than 1 year. The right and left atrial volumes indexed to the body surface areas (right atrial volume index [RAVI] and left atrial volume index [LAVI]) were determined by preacquired contrast-enhanced computed tomography (CT). The %RAVI/LAVI was obtained as 100 × RAVI/LAVI. Results During a median follow-up period of 15 months (interquartile range, 13-19 months), 21 patients (30%) had arrhythmia recurrences after the CPVI. Antiarrhythmic drugs were continued in 34 patients (48%). In the Cox proportional hazard model, the %RAVI/LAVI was a significant positive predictor of arrhythmia recurrences (hazard ratio, 1.048; P = 0.039). A receiver-operating characteristic analysis demonstrated that at an optimal cutoff of 100.1 for the %RAVI/LAVI, the sensitivity and specificity for predicting arrhythmia recurrences were 85.7% and 71.4%, respectively. The Kaplan-Meier analysis showed that arrhythmia recurrences were less frequent in patients with a %RAVI/LAVI of <100.1 than in those with a %RAVI/LAVI of ≥100.1 (P < 0.0001), and the arrhythmia-free survival rate at 12 months was 89.7% and 45.2%, respectively. Conclusions The ratio of the RAVI to LAVI on CT may be a useful predictor of clinical outcomes after CPVI of LSP-AF. LSP-AF patients with a less predominant right atrial enlargement relative to the left atrial enlargement may be good candidates for successful treatment with CPVI alone as the ablation strategy for LSP-AF. [ABSTRACT FROM AUTHOR]

Background The purpose of this study is to assess the electrocardiographic and electrophysiological parameters of conduction abnormalities in patients undergoing transcatheter aortic valve implantation (TAVI) due to severe aortic valve stenosis. Methods The study included 55 patients who underwent TAVI using either the Boston Scientific Lotus (n:25) (Boston Scientific, Natick, MA, USA) or Edwards Sapien XT (n:30) (Edwards Lifesciences, Irvine, CA, USA) prostheses. An electrophysiological study (EPS) was performed in the catheterization room immediately before the initial balloon valvuloplasty and immediately after prosthesis implantation. Results QRS duration and His-bundle to His-ventricle (HV) intervals, which were similar between the two groups before the procedure, were found to be significantly higher in the Lotus valve group postprocedure. Permanent pacemakers (PPMs) were required more frequently in the Lotus group than in the Sapien XT group at discharge (24.0% vs 6.7%, P = 0.07). With the exception of a higher prevalence of paravalvular leakage (P < 0.001) in patients undergoing Sapien XT implantation, other clinical outcomes were similar between the two groups. Multiple regression analysis revealed that baseline atrioventricular (AV) conduction disorders and HV intervals after the procedure were independently associated with PPM implantation after TAVI. Conclusion In this first study comparing the findings of EPS and electrocardiography, the impact of the Lotus valve on AV conduction systems was greater than that of the Sapien XT. However, the need for PPM was higher in the Lotus valve than in the Sapien XT. PPM requirement is related to valve design; it may decrease with reduced frame height and metal burden in novel valve systems. [ABSTRACT FROM AUTHOR]

Background This is a comparative effectiveness study for cardiac resynchronization therapy defibrillator (CRT-D) therapy enabled by quadripolar (QUAD) versus bipolar (BIP) left ventricular (LV) leads. Heart failure (HF) hospitalization (HFH) rates, associated costs, and 30-day readmissions after index HFH were compared. Methods Patients with de novo LV leads implanted as part of a CRT-D system between January 2011 and August 2013 with ≥1-year follow-up were included. Medical history, dates, and locations of HFH were collected thereafter. Patients were divided based on LV lead model: QUAD or BIP. Universal billing records (UB-04) for each HFH and ICD-9-CM (International Classification of Diseases, Ninth Revision, Clinical Modification) diagnoses/procedure codes were used to classify hospitalizations as HF or non-HF and calculate concurrent U.S. national-average medicare reimbursement. Rates, associated payer costs, and 30-day readmissions were then compared using nonparametric bootstrapping. Results Baseline characteristics (N = 69 QUAD and N = 56 BIP) were similar. The inpatient HFH for the QUAD group (0.20/patient-year) was lower than the BIP group (0.31/patient-year, incidence rate ratio [IRR] = 0.62, P = 0.036). The overall HFH rate for the inpatient or outpatient setting for QUAD (0.29/patient-year) was lower than the BIP group (0.42/patient-year, IRR = 0.69, P = 0.055). Average cost of HFH in QUAD ($4,428/patient-year) was lower than BIP ($7,354/patient-year), a 39.8% cost reduction (P = 0.026). The 30-day readmission rate was also lower in QUAD compared to BIP (19% vs 28%, IRR = 0.68, P = 0.18). Conclusion This U.S. economic comparative study demonstrated that QUAD exhibited lower postimplant inpatient HFH rates and reduced healthcare utilization compared to BIP systems. [ABSTRACT FROM AUTHOR]

Background Although a ventriculoatrial interval (VAI) of ≤70 ms is used to distinguish atrioventricular nodal reentrant tachycardia from orthodromic atrioventricular reciprocating tachycardia (AVRT), a VAI of ≤70 ms is sometimes observed in cases of AVRT. The study aimed to evaluate the short VAI that is seen in AVRT and to understand its underlying mechanism. Methods Electrophysiologic studies of 46 consecutive patients with AVRT involving an accessory pathway (AP) were examined retrospectively. Results AP was right sided in seven patients and left sided in 39. A VAI (interval from QRS onset to the earliest intracardiac atrial electrogram recorded by any mapping catheter during AVRT) ≤70 ms during AVRT (short VAI) was observed in eight patients: six with a left lateral AP and two with a left posteroseptal AP. During AVRT involving a left-sided AP, the QRS-V interval (from the earliest QRS onset to the local ventricular electrogram at a site which showed earliest atrial electrogram recorded from the coronary sinus catheter) was significantly shorter (37 ± 7 ms vs 54 ± 13 ms, P = 0.001) and supernormal conduction (QRS duration or the QRS-V interval shortening by ≥10 ms during AVRT) was more frequently seen (63% vs 6%, P = 0.02) in the short VAI group than in the normal VAI group. Furthermore, these parameters were shown to be determinants for short VAI. Conclusions A short VAI is sometimes observed during AVRT involving a left-sided AP. The short VAI may be caused by rapid propagation or supernormal conduction between the proximal Purkinje-muscle junction and basal left ventricular myocardium. [ABSTRACT FROM AUTHOR]

Background Visually guided laserballoon (LB) ablation has recently been introduced for pulmonary vein (PV) isolation (PVI). We analyzed efficacy and safety results of the newly introduced LB ablation technique in patients with persistent and longstanding persistent atrial fibrillation (AF), and compared this with an established standard method using the cryoballoon (CB). Methods A total of 35 patients with symptomatic persistent AF underwent LB ablation and were followed-up for 1 year. Results were compared to 35 patients who underwent CB ablation at the same institution and case matched for age, sex, CHA2DS2-VASc score, and left atrial volume. Results Complete isolation of all PVs was achieved in 68.6% in the LB and 97.1% in the CB group (P < 0.01). No significant differences were found for AF-free survival after 12 months in the complete cohort of all patients (LB: 53.3% vs CB: 70.4%; P = n.s.) and after excluding patients without complete PVI (LB: 57.8% vs CB: 72.5%; P = n.s.). LB ablation resulted in longer procedure (158.5 ± 37.9 minutes vs 110.9 ± 26.5 minutes; P < 0.01) and fluoroscopy durations (28.4 ± 11.1 minutes vs 23.5 ± 9.4 minutes; P = 0.04.), and a trend toward more major complications (14.3% vs 2.9%; P = n.s.). Procedure durations and complications declined over time and were level with CB-treated patients when reaching the last quartile of the LB patients. Conclusion PVI in patients with persistent AF using the LB or the CB resulted in comparable success rates. Initial prolongations in procedure and safety parameters as a result of a learning curve effect for the LB have to be considered before starting to use this technique. [ABSTRACT FROM AUTHOR]

Background Transvenous left ventricular (LV) lead placement for cardiac resynchronization therapy is unsuccessful in 5-10% of reported cases. These patients may benefit from isolated surgical placement of an epicardial LV lead via minithoracotomy approach. Aim To evaluate the success of this approach at long-term follow-up. Methods Retrospective evaluation of all consecutive patients undergoing isolated epicardial LV lead placement after failed transvenous attempt over a 6-year period. Data collected on baseline parameters, procedural details, and outcome at follow-up (hospital stay, complications, mortality, and clinical response). Results Forty-two patients underwent epicardial lead implant. Five died within 1 year (11.9%): two (4.8%) died within 30-days post op (one from intraoperative hemorrhage, the other from multiple organ failure); 39 (95.1%) were admitted to the high dependency unit and transferred to the ward <24 hours. Median hospital stay was 3.4 ± 1.9 days. The overall complication rate was 17.5% (n = 7): 15.0% (n = 6) short term and 2.5% (n = 1) long term; these included three (7.5%) LV noncapture events all treated with reprogramming. There were two (5.0%) wound infections requiring oral antibiotics and two (5.0%) device infections requiring intravenous antibiotics (one had device resiting, the other developed septic shock requiring intensive care admission). Assessment of clinical response was possible in 34 (81.0%) at follow-up: 21 (61.8%) were responders and 13 (28.2%) nonresponders with no significant differences between these groups; no clinical predictors of response were identified. Conclusion Isolated epicardial LV lead implant using minithoracotomy is relatively safe and effective at successful LV pacing. Response rate and postoperative recovery at long-term follow-up are reasonable in these high-risk patients. [ABSTRACT FROM AUTHOR]

Background According to the ACC/AHA/HRS guidelines, cardiac pacing is reasonable in patients with bifascicular block (BF-B) and syncope when other causes have been excluded. The purpose of this study was to assess the long-term outcome of patients with BF-B and unexplained syncope following cardiac pacing. Methods and Results Between 2009 and 2015, we identified 43 consecutive patients (mean age of 78 ± 12 years, 64% males) who presented with syncope and BF-B and had received a pacemaker (PM). During a mean follow-up period of 31 ± 21 months, syncope recurred in seven patients (16%): 7% (95% standard error [SE] ± 3%) at 1 year and 18% (95% SE ± 7%) at 5 years. At univariable analysis, the only predictor of syncope recurrence was empiric pacing (P = 0.03). There were no syncope recurrences in the 12 patients who received a PM following a positive electrophysiological study (EPS) and the five patients with documentation of paroxysmal atrioventricular block (AVB) during cardiac monitoring (insertable loop recorder [ILR]), (EPS/ILR Group, n = 17) compared to seven of 26 (27%) patients who received empiric pacing (Empiric Group, n = 26; P = 0.02). Progression to high-degree AVB was documented during follow-up in 16 (37%) patients: nine of 17 (53%) patients in the EPS/ILR Group and seven of 26 (27%) patients in the Empiric Group (P = 0.11). There were no injuries reported during ILR monitoring. Conclusions We have shown that syncope recurs not infrequently in patients with BF-B who received pacing for syncope. Nearly one in four patients who had empiric pacing suffered syncope recurrence compared to no recurrences in patients who received a PM following a positive EPS or documentation of transient AVB. [ABSTRACT FROM AUTHOR]

Background Pneumothorax (PTX) is a major cause of morbidity associated with cardiac implantable electronic devices (CIEDs). We sought to evaluate predictors of PTX at our centers during CIED implantations, including the venous access technique utilized, as well as to determine morbidity and costs associated with PTX. Methods We reviewed records of all patients undergoing cardiac device implant or revision with new venous access at our institutions between 2008 and 2014. Common demographic and procedure characteristics were collected including age, sex, body mass index (BMI), comorbidities, and method of venous access (axillary vein vs classic proximal subclavian vein technique). Results We identified 1,264 patients who met criteria for our analysis, with a total of 21 PTX cases during CIED implantation. The strongest predictor for PTX was the venous access strategy: 0 of 385 (0%) patients with axillary vein approach versus 21 of 879 (2.4%) with traditional subclavian vein approach, P = 0.0006. Additional predictors of PTX included advanced age, female sex, low BMI, and a new device implant (vs device upgrade). The occurrence of PTX was associated with increased length of stay: 3.0 days (median; interquartile range [IQR] 3) versus 1.0 day (median; IQR: 1), P = 0.0001, with a cost increase of 361.4%. Conclusion An axillary vein vascular access strategy was associated with greatly reduced risk of iatrogenic PTX versus the traditional subclavian approach for CIED placement. Similarly, device upgrade with patent vascular access carried less risk of PTX compared to new device implantation. PTX occurrence significantly prolonged hospitalization and increased costs. [ABSTRACT FROM AUTHOR]

Background Patients with myotonic muscular dystrophy (dystrophia myotonica, DM) are at risk of sudden cardiac death due to diverse arrhythmias, especially progressive atrioventricular (AV) conduction abnormalities. However, there are limited data on supraventricular and potentially life-threatening ventricular arrhythmias, especially according to type 1 and type 2 DM. Methods A group of 94 unselected consecutive patients with genetically confirmed DM and 45 healthy controls underwent electrocardiography, echocardiography, and 24-hour Holter monitoring. DM1 was diagnosed in 51, while DM2 in 43 patients (with mean age of 37.3 ± 12.5 and 48.3 ± 13.3 years, respectively). Results DM1 subjects presented more frequently intraventricular conduction defects (29.4% vs 6.6%, P = 0.0003) and first-degree AV block (25.0% vs 4.6%, P = 0.008) than DM2 patients. Nonsustained supraventricular tachycardia (37.2% vs 3.8%, P = 0.001) and nonsustained ventricular tachycardia and/or R-on-T ventricular beats (23.2% vs 7.8%, P = 0.04) were more frequently observed in DM2 than in DM1. No relationship between disease duration and neurological status and occurrence of arrhythmias was observed. Multivariate analysis showed that independent predictor for bradyarrhythmias occurrence was DM1 only (odds ratio [OR] 6.4, 95% confidence interval [CI] 2.0-20.8, P = 0.002), while for supraventricular or ventricular arrhythmias occurrence it was DM2 (OR 4.1, 95% CI 1.5-11.4, P = 0.007) and increased age (OR 1.09, 95% CI 1.05-1.15, P < 0.0001). Conclusions In the relatively large groups of DM1 and DM2 patients, we observed frequent various arrhythmias, which warrant their close cardiac monitoring. DM1 subjects when compared to DM2 presented more frequently intraventricular and AV conduction defects. However, all types of tachyarrhythmias (except atrial fibrillation) were more frequently observed in DM2 patients. [ABSTRACT FROM AUTHOR]

Background Preprocedure systemic antibiotic prophylaxis reduces infections in patients undergoing cardiac implantable electronic devices (CIEDs) implantations. Whether pocket irrigation with antibiotic solution offers any advantage over saline solution in CIED implantation is unknown. Methods Records from 327 consecutive patients who underwent CIED implantation by three operators from February 2011 to January 2014 were reviewed. From February 2011 to January 2012, the antibiotic solution was used for pocket irrigation; from February 2012 to January 2014, saline solution was used. All patients received preprocedural IV antibiotics. Baseline demographics, comorbidities, lab data, and occurrence of any pocket infection postimplant were collected. Results There were 118 and 209 patients in the antibiotic solution and saline solution group, respectively. A total of four (1.2%) patients had CIED infection: two in the antibiotic solution group and two in the saline solution group. Median time to infection from implant date was 81.5 ± 35 days. Two patients (50%) had infection after first device implantation. Of the four patients, one had positive blood culture, three had positive pocket cultures, one had lead vegetation, one underwent pocket exploration, and all of them had devices/leads extracted, with reimplantation on the contralateral side. No mortality was observed due to infectious complications. Conclusion When compared to pocket irrigation in the antibiotic solution group, the saline solution group was not associated with increased incidence of infectious complications after CIED implantation. The use of saline solution pocket irrigation alone may be used in CIED pocket irrigation periprocedurally. Further evaluation in larger randomized trials is needed. [ABSTRACT FROM AUTHOR]

Background Atrial fibrillation (AF) is an arrhythmia that can be difficult to identify and classify with short-term monitoring. However, current standard of practice requires only short-term monitoring to determine AF classifications and identify symptom-arrhythmia correlations prior to AF ablation procedures. Insertable cardiac monitors (ICMs) offer continuous arrhythmia monitoring, which could lead to a more accurate measurement of AF burden than standard of practice. Methods This analysis focused on 121 patients enrolled in the LINQ Usability Study indicated for an AF ablation. Patients were followed for up to 1 year after ICM insertion. Clinical AF classifications were made by physicians prior to ICM implantation based on available clinical information. Device-detected AF burden and maximum daily burden were collected from device interrogations and remote transmissions. Device AF classifications were determined by categorizing the AF burden based on guidelines. Results Agreement between clinical and device AF classifications preablation was poor (48.3%, N = 58). The strongest agreement was in the paroxysmal AF group but still was only 61.8%. Furthermore, device-detected preablation AF burden led to the decision to defer AF ablation procedures in 16 (13.2%) patients. The median AF burden in patients with ≥6 months follow-up postablation (n = 71) was reduced from 7.8% (interquartile range [IQR]: 0-32.1%) to 0% (IQR: 0-0.7%). Conclusions ICM monitoring to determine AF burden pre- and post-AF ablation may have clinical utility for management of ablation candidates through more accurate AF classification and guiding treatment decisions. [ABSTRACT FROM AUTHOR]

Background The impact of inappropriate implantable cardiac defibrillator (ICD) shocks on cardiac outcomes is controversial. Shocks due to lead noise are unique in that they are not an outcome of worsening rhythm status. In this study, we compared the outcome of patients with and without inappropriate shocks who underwent Sprint Fidelis lead (Medtronic Inc., Minneapolis, MN, USA) extraction. Methods We retrospectively identified 147 patients who underwent Sprint Fidelis lead extraction in our institution between May 2007 and August 2012. The patients were separated into those with (Group 1) and without (Group 2) inappropriate shocks due to lead noise. Pertinent data were obtained from chart review. Results There were 57 and 90 patients in Groups 1 and 2, respectively. The mean ± standard deviation number of inappropriate shocks in Group 1 was 16 ± 22. There was no difference in the baseline demographics, risk factors, and cardiac history between the groups. There were no extraction-related deaths and there was no difference in the rate of periprocedural complications between the groups. The mean total hospital length of stay (LOS) was longer for Group 1 versus 2; however, the mean postprocedure LOS was the same between the groups. During follow-up, there was no difference in the cardiac readmission rate over a 1-year period (four vs seven patients in Group 1 vs 2, respectively; P = 0.8). Long-term follow-up revealed similar mortality rates in both groups. (18 patients in Group 1, and 21 patients in Group 2; P = 0.8). Conclusions Inappropriate shocks due to lead noise do not seem to predispose to a worse clinical outcome after ICD lead extraction. [ABSTRACT FROM AUTHOR]

Background Cryoablation is increasingly utilized in children because of its safety profile. Recently, larger catheter tips have been more widely used to improve long-term success rates. The aim of this study was to assess the safety and efficacy of 8-mm-tip catheters for cryoablation of right-sided accessory pathways (APs) in children. Methods Electrophysiological procedures were performed using the EnSite™ system (St. Jude Medical Inc., St. Paul, MN, USA). Results Between July 2010 and July 2014, 54 patients (mean age: 13.1 ± 3.7 years) underwent cryoablation using an 8-mm-tip catheter. In 18 of 54 (33%) patients where an 8-mm-tip catheter was the first-choice catheter, the success rate was 18 of 18 (100%). There was a history of previous failed attempts or recurrence with radiofrequency ablation and/or 6-mm-tip cryoablation in 36 of 54 (67%) patients. The success rate in these patients was 24 of 36 (67%). No fluoroscopy was used in 34 of 54 procedures. The recurrence rate was six of 42 (14%) during a mean follow-up period of 32 ± 15 months. In one patient, transient atrioventricular block occurred. Conclusions Cryoablation with an 8-mm-tip catheter for right-sided APs in children who weigh over 40 kg appears to be safe and acutely effective in cases where conventional ablation methods fail and also as a first choice for ablation procedure. However, the recurrence rate still seems to be high. [ABSTRACT FROM AUTHOR]

Background Ischemic cardiomyopathy (ICM) can provide the substrate for ventricular tachycardia (VT). Objective To map noninvasively with high resolution the electrophysiologic (EP) scar substrate, identify its relationship to reentry circuits during VT, and stratify VT risk in ICM patients. Methods Noninvasive high-resolution epicardial mapping with electrocardiographic imaging (ECGI) was performed in 32 ICM patients (17 with clinical VT, 15 without VT). Abnormal scar EP substrate was determined based on electrogram (EGM) amplitude (as percentage of maximal peak-to-peak voltage over the entire ventricular epicardium; total scar [TS] < 30%; dense scar [DS] < 15%), fractionation, and presence of late potentials (LPs). Scar burden was defined as the ratio of the scar size to the total epicardial surface area. The VT activation pattern was mapped and correlated with the EP substrate to identify components of the reentry circuit. Results Patients with VT had higher scar burden (TS: 51.0 ± 9.3% vs 36.5 ± 5.4%, P < 0.05; DS: 29.5 ± 7.3% vs 16.8 ± 6.8%, P < 0.05) with lower normalized unipolar EGM voltage (TS: 0.107 ± 0.027 vs 0.153 ± 0.031, P < 0.05; DS: 0.073 ± 0.023 vs 0.098 ± 0.026, P < 0.05), greater prevalence of fractionated EGMs (TS: 44.1 ± 10.6% vs 26.8 ± 6.3%, P < 0.05; DS: 50.8 ± 10.8% vs 30.9 ± 7.0%, P < 0.05), and LPs (TS: 26.8 ± 10.7% vs 15.8 ± 5.3, P < 0.05). VTs were mapped in eight patients; the reentry circuits were closely related to the EP substrate. Conclusions ECGI noninvasively identified scar EP substrate that underlies abnormal conduction in ICM patients. It identified regions within the scar that aligned with critical elements of the reentry circuit during VT. ECGI can potentially be used for VT risk stratification in ICM patients. [ABSTRACT FROM AUTHOR]

Background Nonsustained ventricular tachycardia (NSVT) detected by ambulatory Holter (Holter NSVT) is a major risk factor for sudden cardiac death in hypertrophic cardiomyopathy (HCM). We hypothesized that the prognostic utility of Holter NSVT in HCM would improve with prolonged monitoring and a higher heart rate cut-off for detection. Methods We enrolled 60 patients (44 ± 14 years) with HCM, who had a prophylactic implantable cardioverter defibrillator (ICD). Positive Holter NSVT (prior to implant) was defined as ≥3 beats at ≥120 beats per minute (bpm). We assessed the prevalence of rapid NSVT (RNSVT) detected by their ICD within 12 months of its implant, defined as 4-16 beats at ≥150-200 bpm. The primary outcome was appropriate ICD therapy (antitachycardia pacing and shocks) for sustained ventricular arrhythmia (VA). Results Holter NSVT was detected in 34 patients. RNSVT occurred in 21 (35%) patients of whom five did not have Holter NSVT. Over a median follow-up of 61 (interquartile range 29, 129) months after ICD implant, nine patients had VA. RNSVT, but not Holter NSVT, was significantly associated with VA (hazard ratio 6.2, 95% confidence interval [1.3-30], P = 0.01) by multivariable Cox regression analysis that included conventional risk factors. Receiver operating characteristic analysis for RNSVT (area under curve 0.80, P = 0.005) showed that the occurrence of ≥2 episodes of RNSVT discriminated patients for VA optimally (sensitivity 78%, specificity 84%, positive predictive value 47%, negative predictive value 96%). Conclusions In this pilot study, RNSVT detected by continuous monitoring independently predicted VA in HCM and offered superior discrimination of VA risk compared to conventional risk factors, including Holter NSVT. Future studies are needed to validate these findings in a larger, unselected HCM cohort. [ABSTRACT FROM AUTHOR]

Background Left ventricular ejection fraction (LVEF) recovers during follow-up in a significant proportion of patients implanted with a cardioverter defibrillator (ICD) for primary prevention. Little is known about the midterm arrhythmic risk in this population, particularly in relation to the presence or absence of ischemic cardiomyopathy. Methods and Results We retrospectively analyzed 286 patients with an ICD implanted for primary prevention between 2002 and 2010. Patients were divided into two groups based on their last LVEF assessment: (1) Recovery, defined as an LVEF > 35%; and (2) No-Recovery, defined as an LVEF ≤ 35%. Kaplan-Meir curves and multivariate Cox regression analysis were performed separately for patients with ischemic (211 patients) and nonischemic (75 patients) cardiomyopathy. Forty-nine patients (17.1%) had LVEF recovery to >35% at last follow-up. Overall, 72 patients (25.2%) experienced ventricular arrhythmias requiring ICD therapy during a median follow-up of 4.4 years. With multivariate Cox regression, LVEF recovery was associated with a lower arrhythmic risk in the whole cohort (hazard ratio [HR]: 0.38 [0.13-0.85]; P = 0.02) and in the nonischemic cardiomyopathy cohort (HR: 0.10 [0.005-0.55]; P = 0.005), but not in the ischemic cardiomyopathy cohort (HR: 0.84 [0.25-2.10]; P = 0.74). Conclusion In conclusion, patients with nonischemic cardiomyopathy who improved their LVEF to >35% after primary prevention ICD implantation were at very low absolute arrhythmic risk. Our study raises the possibility that the LVEF cutoff to safely withhold ICD replacement might be higher in patients with ischemic compared to nonischemic cardiomyopathy. This will need to be confirmed in prospective studies. [ABSTRACT FROM AUTHOR]

Background Cardiac resynchronization defibrillator (CRT-D) devices improve survival for New York Heart Association classes II-IV systolic heart failure patients with QRS > 120 ms and left ventricular ejection fraction < 35%. A limitation of 100% CRT pacing is excess battery depletion and pulse generator (PG) replacement compared to VVI or dual-chamber systems. Ampere hour (Ah) measures PG battery capacity and may predict CRT-D device longevity. Methods We performed a multicenter retrospective study of all CRT-D devices implanted at our centers from August 1, 2008 to December 31, 2010. Analysis was performed for survival to elective replacement indicator (ERI) between 1.0 Ah, 1.4 Ah, and 2.0 Ah devices, per manufacturers' specifications. Results One thousand three hundred and two patients were studied through December 31, 2014. Patients were followed for an average of 3.0 ± 1.3 years (794 1.0 Ah, 322 2.0 Ah, and 186 1.4 Ah devices under study). CRT-D generator ERI occurred in 13.5% of 1.0 Ah systems (107 out of 794), versus 3.8% in 1.4 Ah (seven out of 186), and 0.3% in 2.0 Ah devices (one out of 322) over mean follow-up of 3.0 years. Odds ratio (OR) for reaching ERI with 1.0 Ah device versus 1.4 Ah or 2.0 Ah was 9.73, P < 0.0001. Univariate predictors for ERI included 1.0 Ah device and LV pacing output >3V @ 1 ms (OR: 3.74, P < 0.001). LV impedance >1,000 ohms predicted improved device survival (OR: 0.38, P = 0.0025). Conclusions CRT-D battery capacity measured by Ah is a strong predictor of survival to ERI for modern systems. Further study on cost and morbidity associated with early PG change in 1.0 Ah systems is warranted. [ABSTRACT FROM AUTHOR]

Background Different types of ventricular arrhythmias (monomorphic ventricular tachycardia [VT], polymorphic VT, or ventricular fibrillation) can be detected by implantable cardiac defibrillators (ICDs) in fast VT zone. The efficacy of antitachycardia pacing (ATP) depends on the type of the treated arrhythmia. We hypothesized that an automatic algorithm based on morphological affinity of ICD far-field electrograms during tachycardia can predict ATP success and the need of shock. Methods The algorithm was evaluated on ventricular arrhythmias recorded in CareLink ICD remote monitoring system (Medtronic Inc., Minneapolis, MN, USA). Patients were selected if first ATP programmed was a burst of eight pulses at 88% coupling interval and if a far-field electrogram was available. The algorithm calculated a stability coefficient (SC) for all their stored ATP-treated fast ventricular arrhythmia (VA) episodes (LC 200-300 ms), analyzing the morphology homogeneity of the last eight recorded far-field electrograms before ventricular arrhythmias detection. Results Inclusion criteria were fulfilled by 717 patients from 29 centers. Three hundred and twenty fast VA were recorded in 103 patients. A higher SC was observed in episodes terminated with the first-ATP (0.78 [0.72-0.84] vs 0.74 [0.60-0.84]; P = 0.006). These differences were especially marked among the 62 episodes of very fast VA (CL ≤250 ms) (0.77 [0.74-0.85] vs 0.64 [0.51-0.8]; P = 0.006). In the multivariate analysis, a SC > 70% was independently associated with a higher likelihood of first-ATP success (odds ratio [OR] = 2.5; [95% confidence interval (CI) = 1.4-4.5], P = 0.001) and a lower need of shock (OR = 0.37; [95% CI = 0.2-0.7], P = 0.002). Conclusion This automatic algorithm (stability coefficient) shows that ATP therapy response can be predicted in fast ventricular arrhythmias through morphology evaluation. [ABSTRACT FROM AUTHOR]