BACKGROUND Frequent premature ventricular complexes (PVCs) are common after a myocardial infarction (MI), but data on PVC ablation in this population are limited. OBJECTIVE The purpose of this study was to analyze data on PVC ablation in post-MI patients. METHODS Three hundred thirty-two patients with frequent PVCs and left ventricular (LV) dysfunction were prospectively studied. Data from 67 patients (20%; age 63 +/- 10 years; 65 men [93%]) with previous MI were compared with the remaining 265 patients. RESULTS PVCs in post-MI patients originate predominantly from the LV (92% LV vs 6% right ventricle [RV]; P <.001). The most frequent sites of origin (S00) were MI scar in 23 patients (34%) and left ventricular outflow tract (LVOT) in 22 patients (33%). A papillary muscle origin was more frequent in post-MI patients (16% vs 4%; P = .001), whereas an RV outflow tract origin was less frequent (1% vs 33%; P < .001) compared to patients without MI. In post-MI patients, PVC burden decreased from 29% +/- 12% at baseline to 4.6% +/- 7% (P <.001); left ventricular ejection fraction (LVEF) improved from 33.6% +/- 8% to 42% +/- 10% (P <.001); and New York Heart Association functional class improved from 2.1 +/- 0.7 to 1.4 +/- 0.5 points (P <. 001) at 12 months. Compared with the remaining 265 patients, there were no differences in acute ablation success (85% vs 85%; P = .45), complication rate (6% vs 6%; P = .41), or absolute improvement in LVEF (8.8 +/- 10 vs 9.9 +/- 11 absolute points; P = .38). CONCLUSION PVC ablation significantly improves cardiac function and functional status in post-MI patients. PVCs predominantly originate from MI scar and LVOT. A papillary muscle SOO was found to be strongly associated with previous MI.

The authors report no conflicts of interest for the published content. Address correspondence to: Paolo D. Dallaglio, MD. Email: paoloddallaglio@hotmail.com. Left ventricular (LV) assist devices (LVADs) are a treatment option in patients with advanced heart disease. Ventricular tachycardias (VTs) are common in patients with continuous-flow LVADs and have been associated with increased mortality rates.1 In this new clinical scenario, ablation has been proposed as a very promising treatment tool.2 Herein, we report a case of VT ablation in a 67-year-old patient with ischemic cardiomyopathy and severe LV dysfunction who had previously received an LVAD (HeartMate III) implanted as a bridge to heart transplantation. The patient was admitted to the intensive care unit due to multiple VT episodes with a suspected inferolateral and apical origin (Figure 1). VT episodes were resistant to antiarrhythmic drugs and to antitachycardia pacing, so a decision was made to perform VT ablation.

Abstract Funding Acknowledgements Type of funding sources: None. Background Epidemiological studies suggested that premature ventricular complexes (PVCs) are associated with cardiac mortality. But data are still inconclusive. Aim This study sought to analyze predictors of adverse outcomes in a population of patients with left ventricular (LV) systolic dysfunction who underwent PVC ablation. Methods 135 consecutive patients [100 (74%) men, 59 +12 y.o.] with LV systolic dysfunction [LV ejection fraction (LVEF) <50%] and frequent PVCs who underwent PVC ablation were included in a multicenter prospective international register. Patients were followed-up at 6 and 12 months and annually thereafter. The last evaluation performed was considered the long-term follow-up (LTFUP) evaluation. Cardiac mortality and/or cardiac transplantation and/or admission for heart failure was considered the primary endpoint. Results 82 (61%) patients had a left-sided PVC’s site of origin (LS-SOO), 51 (38%) had a right-sided SOO (RS-SOO) whereas SOO could not be determined in 2 (1%) patients. LS-SOO patients were older (61 ± 11 vs 52 ± 10, p < 0.001) more frequently men [71 (87%) vs 27 (53%), p < 0.001] with previous history of atrial fibrillation (AF) [14 (15%) vs 0, p = 0.001] and with a previously diagnosed structural heart disease (SHD) [43 (52%) vs 6 (11%), p < 0.001]. After a mean follow-up of 39 ± 21 months (range 24-94 months) there was a significant reduction in the PVC burden from 24 ± 13% at baseline to 4 ± 6% at LTFUP, p < 0.001; LVEF improved from 33 ± 8% at baseline to 41 ± 13% at LTFUP (p < 0.001) and NYHA class from 2.1 ± 0.6% to 1.4 ± 0.6% (p < 0.001); BNP levels decreased from 237 ± 231 pg/mL to 137 ± 185 pg/mL (p = 0.001). The primary end-point was reached in 10% patients (7 cardiac deaths, 1 cardiac transplantation and 5 heart failure admisions), 14,8% in LS-SOO and 1,9% in RS-SOO patients, log rank = 0.05 (Figure 1). Conclusions Among patients with LV dysfunction who underwent PVC ablation, those with LS-SOO were older and more frequently had AF and SHD. LS-SOO was associated with adverse cardiovascular outcomes. These findings suggest that PVCs with LS and RS-SOO should be considered as two different clinicals entities, with different prognostic values. Abstract Figure 1

BACKGROUND:Hypertrophic cardiomyopathy (HCM) carries an increased risk of sudden death due to ventricular arrhythmias (VAs). The implantable cardioverter-defibrillator (ICD) is a well-established therapy for treatment of VA. Monomorphic ventricular tachycardias (MVTs) are frequent in HCM patients and suitable for antitachycardia pacing (ATP) termination. OBJECTIVE:The purpose of this study was to describe ventricular tachycardia (VT) characteristics in a population of HCM patients with ICD and to study the effectiveness and safety of ATP for MVT. METHODS:Data were obtained from the multicenter prospective observational UMBRELLA trial, which included all patients with HCM and ICD followed by the CareLink Monitoring System. All episodes of VA were collected and analyzed. ATP effectiveness and safety were described, and factors related to ATP effectiveness were studied with generalized estimating equation (GEE) models. RESULTS:Among 251 patients followed for 47 months, 67 (26.7%) were implanted as secondary prevention. Fifty-six patients presented 326 episodes of VA (286 [87%] MVT). Mean cycle length was 312 ± 64 ms. Among 264 MVTs that received ICD therapy, 202 (76.5%) were ATP terminated. The first ATP burst was effective in 169 episodes (68.4%), and overall effectiveness of the first or second ATP burst was 73.8%. Multivariate GEE-adjusted analysis showed 2 variables related to ATP effectiveness: programming fast VT zone On vs Off (odds ratio [OR] 2.4; 95% confidence interval [CI] 1.5-5.2; P = .03) and programming ≥2 ATP bursts vs 1 burst only (OR 1.6; 95% CI 1.2-3.4; P = .04; and OR 2.9; 95% CI 1.8-6.3; P = .02; respectively). CONCLUSION:MVT is the predominant VA in HCM patients with ICD. ATP is highly effective in terminating the majority of MVTs, and its proved effectiveness should guide device selection and programming in order to avoid unnecessary high-energy shocks.

AIMS Frequent premature ventricular complexes (PVCs) can induce or worsen left ventricular systolic dysfunction. We aimed to investigate the influence of the baseline QRS in the response after PVC ablation in patients with depressed left ventricular ejection fraction (LVEF). METHODS AND RESULTS Two hundred and fifteen [59 ± 13 years old, 152 (71%) men] consecutive patients with left ventricular (LV) systolic dysfunction and frequent PVCs referred for ablation were included and followed-up for 12 months. Echocardiographic response was defined as an improvement of at least five absolute points in LVEF. Clinical, electrocardiogram, and electrophysiological characteristics were analysed. Mean baseline QRS duration was 110 ms [97-140]. Premature ventricular complex burden significantly decreased after ablation from 23% [16-33] at baseline to 1% [0-8] at 12 months, P < 0.001. Mean PVC burden reduction was 18 [8-30] points. There was a significant improvement of LVEF from 35% [29-40] at baseline to 44% [35-55] at 12 months, P < 0.001. One hundred and thirty (61%) patients were considered as echocardiographic responders. Baseline QRS duration (ms) [odds ratio (OR) 0.98 (0.97-0.99), P = 0.01] was an independent predictor of echocardiographic response. Mean LVEF improvement was 16 [10-21] points when the baseline QRS duration was <90 ms; 12 [4-20] when it was 90-110 ms; 5 [0-15] when it was 110 ± 130 ms; and 0 [0-6] points when it was >130 ms. CONCLUSIONS In patients with LV systolic dysfunction, intrinsic QRS duration is inversely related to the probability and the degree of echocardiographic response after frequent PVC ablation. Patients with a QRS duration >130 ms at baseline have the poorer response after ablation.

Aims Ablation of frequent premature ventricular complexes (PVCs) improves left ventricular ejection fraction in patients with left ventricular (LV) systolic dysfunction. This study aims to evaluate the long-term hard outcomes and potential prognostic variables in this population. Methods and results Prospective multicentre study including 101 consecutive patients [56 +/- 12 years old, 62 (61%) men] with LV systolic dysfunction and frequent PVCs who underwent PVC ablation before November 2015. The last evaluation performed was considered the long-term follow-up (LTFUP) evaluation. Mean follow-up was 34 +/- 16 months (range 24-84 months). Ablation was successful in 95 (94%) patients. There was a significant reduction in the PVC burden from 21 +/- 12% at baseline to 3.8 +/- 6% at LTFUP, P < 0.001. Left ventricular ejection fraction improved from 32 +/- 8% at baseline to 39 +/- 12% at LTFUP (P < 0.001) and New York Heart Association class from 2.2 +/- 0.6% to 1.3 +/- 0.6% (P < 0.001). Brain natriuretic peptide levels decreased from 136 (78-321) to 68 (32-144) pg/mL (P = 0.007). Most of this improvement occurs during the first 6 months after ablation. Persistent abolition of at least 18 points of the baseline PVC burden was independently and inversely associated with the composite endpoint of cardiac mortality, cardiac transplantation, or hospitalization for heart failure during follow-up [hazard ratio 0.18 (0.05-0.66), P = 0.01]. Conclusion In patients with LV systolic dysfunction, ablation of frequent PVCs induces a significant improvement in functional, structural, and neurohormonal status, which persists at LTFUP. A sustained reduction in the baseline PVC burden is associated with a lower risk of cardiac mortality, cardiac transplantation, or hospitalization for heart failure during follow-up.

Bundle branch reentrant ventricular tachycardia (BBRVT) is characterized by a unique, fast (200–300 beats/min), monomorphic wide complex tachycardia associated with syncope, hemodynamic compromise, and cardiac arrest. BBRVT is a reentrant VT with a well-defined reentry circuit, incorporating the right bundle branch (RB) and left bundle branch (LB) as obligatory limbs of the circuit, connected proximally by the His bundle (HB) and distally by the ventricular septal myocardium. It is often challenging to diagnose, usually requiring a His bundle recording and specific pacing maneuvers.

This report presents the findings of the 2018 Spanish Catheter Ablation Registry.Data collection was retrospective. A standardized questionnaire was completed by each of the participating centers.Data sent by 100 centers were analyzed, with a total number of 16 566 ablation procedures performed (the highest historically reported in this registry) for a mean of 165.5 ± 127.9 and a median of 119 procedures per center. The ablation targets most frequently treated were atrial fibrillation (n = 4234; 25.6%), atrioventricular nodal re-entrant tachycardia (n = 3525; 21.3%) and cavotricuspid isthmus (n = 3425; 20.7%). A new peak was observed in the ablation of atrial fibrillation, increasing the distance from the other substrates. The overall success rate was 91%. The rate of major complications was 2.2%, and the mortality rate was 0.04%. A total of 2.1% of the ablations were performed in pediatric patients.The Spanish Catheter Ablation Registry enrolls systematically and continuously enrolls the ablation procedures performed in Spain, showing a progressive increasing in the number of ablations over the years, with a high success rate and low percentage of complications.Se describen los resultados del Registro Nacional de Ablación con Catéter correspondientes al año 2018.La recogida de datos se ha realizado de manera retrospectiva con la cumplimentación de un formulario de recogida de datos por cada uno de los centros participantes.Se han analizado los datos enviados por 100 centros, con un número total de procedimientos de ablación de 16.566, el más alto comunicado históricamente en este registro (con una media de 165,5 ± 127,9 y una mediana de 119 procedimientos por centro). Se consolida la ablación de fibrilación auricular como el sustrato abordado con más frecuencia (n = 4.234; 25,6%), seguida de la taquicardia por reentrada nodular (n = 3.525; 21,3%) y el istmo cavotricuspídeo (n = 3.425; 20,7%). Se observa un nuevo pico en el número de procedimientos de ablación de fibrilación auricular y aumenta la distancia respecto a los demás sustratos. La tasa total de éxito fue del 91%; la de complicaciones mayores, del 2,2% y la mortalidad, del 0,04%. El 2,1% de las ablaciones se realizaron en pacientes pediátricos.El Registro Nacional de Ablación con Catéter con Catéter recoge sistemática e ininterrumpidamente los procedimientos de ablación realizados en España, lo que permite observar a lo largo de los años un aumento progresivo del número de ablaciones manteniendo una tasa de éxito elevada y unos porcentajes de complicaciones bajos.

The incidence of atrial fibrillation (AF) in congenital heart disease (CHD) adults has increased in the past decades due to a longer life expectancy of this population where the subjects are exposed to cardiac overflow, overpressure and structural changes for years. The literature regarding AF ablation in repaired CHD adults emphasizes the importance of intracardiac echocardiography (ICE) to perform the transseptal puncture and the ablation procedure in the left atrium (LA), both effectively and safely. In small case control studies, where the predominant congenital cardiomyopathy was the atrial septal defect, the most common strategy for ablation was antral isolation of the pulmonary veins showing results, at one year follow-up, similar to those in the general population. The positive results of AF ablation so far, in this specific population, widen the range of therapeutic options for a group of patients whose only chance has been pharmacological treatment, which has proved to be inefficacious in most of the cases and not free from adverse events.

Background: Regular intense physical exercise causes cardiovascular adaptations as well as functional and morphological changes in the athlete's heart. The aim of the present study is to characterize those changes using conventional echocardiography and new speckle tracking techniques to study myocardial deformation.Methods: 68 men were studied. 38 long distance runners (42 +/- 8 years), and 30 sedentary controls (40 +/- 7 years). Standard transthoracic echocardiography was performed: M mode, 2D, tissue and colour Doppler. Deformation parameters were studied by speckle tracking at short axis view basal (B), medium (M) and apical (Ap) levels and apical 4 and 2 chamber view of the left ventricle (LV) and right ventricle (RV). Longitudinal, radial and circumferential strain (S) and strain rate (SR) were measured as well as rotation (Rot) and untwisting (UT) at basal and apical levels.Results: Left ventricular ejection fraction and volumes were significantly higher in the athlete group. There were no differences in conventional diastolic parameters. Longitudinal and circumferential left ventricular strain and torsion were higher in the athlete group (p=0.02, p=0.005 and p=0.03 respectively). In addition, radial strain was lower in the athlete group. Right ventricular diameters, tricuspid annular plane systolic excursion (TAPSE) and longitudinal deformation were significantly higher in the athlete group (p=0.01, 0.002 y 0.006 respectively).Conclusion: Myocardial deformation parameters, studied by longitudinal and circumferential strain, as well as ventricular torsion are greater in athletes as compared to sedentary individuals. This increased myocardial longitudinal and circumferential deformation and ventricular torsion might represent an adaptive response to regular intense physical exercise.

Aspirin and Low Molecular Weight Heparin in Patients Undergoing Catheter Ablation of AFBackgroundTo prevent thrombo‐embolic (TE) events during ablation of atrial fibrillation (AF), warfarin is recommended in all patients irrespective of baseline TE risk. We evaluated the efficacy and safety of a simplified periprocedural anticoagulation strategy of aspirin (ASA) and low molecular weight heparin (LMWH) in patients at low TE risk.MethodsWe collected data from 214 low TE risk patients (CHADS2 score ≤1 and no warfarin at baseline) undergoing pulmonary vein isolation. After discontinuation of ASA, periprocedural antithrombotic therapy consisted of therapeutic subcutaneous LMWH injections (nadroparin 1 mL/kg once daily) from 10 days before until 10 days after the procedure, followed by ASA in all patients. At the time of procedure, transesophageal echocardiography (TEE) was not performed on a routine basis. During the procedure, unfractionated heparin was administered to achieve an ACT between 350 and 400 seconds. Data on TE events (stroke or transient ischemic attack), cardiac tamponade/perforation, and major vascular access complications within 3 months after the procedure were collected.ResultsMean CHADS2 was 0.3 ± 0.5. TEE was performed in 3% of patients. No periprocedural TE events occurred. No cardiac tamponade/perforation was observed. Major vascular access complications occurred in 3 patients (1.4%). No permanent injury was observed (0%).ConclusionIn selected low TE risk patients undergoing ablation for AF, a short period of periprocedural therapeutic anticoagulation with LMWH together with aspirin is an effective and safe strategy to prevent TE events. If confirmed in a randomized trial, this approach might simplify periprocedural antithrombotic management in ablation of selected AF patients.

Atrial fibrillation (AF) is the most prevalent arrhythmia in western countries and it is estimated that its prevalence will increase further over the coming decades. AF affects 1% of the general population and up to 17% of patients aged >84 years.1 Until recently, pharmacological therapy has been the only treatment, but its efficacy is limited in terms of maintenance of sinus rhythm and control of symptoms.2 Over the last decade catheter based ablation of AF has proved to be more efficacious in comparison to medical treatment,3 especially in the paroxysmal form. Moreover, the catheter ablation strategy has evolved considerably, leading to significant improvements in efficacy and reductions in the procedural complication rate. Initially, linear lesions were performed in the atria mimicking the surgical Maze procedure4 which, however, resulted in limited success and significant complications. Haissaguerre et al 5 and Chen et al 6 found that AF is most commonly initiated by a premature beat from the orifices of the pulmonary veins (PVs). As a result, the procedure initially targeted elimination of foci inside the triggering vein (the earliest PV electrogram that initiates tachycardia), but this strategy was not effective enough to prevent recurrences which originated from the same or other veins. Therefore, electrical disconnection of all four PVs from the atrium became the proposed treatment option. The antral (also called circumferential) isolation of the veins is the approach that is most frequently used nowadays,7 and in many cases cures the disease. As the atrium becomes more dilated and fibrotic, other structures in addition to PVs are increasingly being recognised as a possible source of AF initiation and/or are key in the perpetuation of AF. Typical locations of triggers and the micro-reentry circuit are one or more of the following atrial structures: left lateral ridge (LLR), left …

QRS-Based Optimization of Cardiac ResynchronizationBackgroundOptimization of atrioventricular (AV) and interventricular (VV) intervals may improve cardiac resynchronization therapy (CRT) response but is a complex task. Fusion with intrinsic conduction may increase the benefit of CRT. The aim was to describe fusion-optimized intervals (FOI), a new method of optimizing CRT based on QRS duration.Methods and ResultsSeventy-six consecutive patients with preserved AV conduction who received CRT were prospectively included. The AV interval was optimized by searching the narrowest QRS obtained within the fusion band during left ventricular (LV) pacing. The VV interval was then adjusted, comparing QRS duration in simultaneous biventricular, LV preexcitation (-30milliseconds), right ventricular (RV) preexcitation (-30milliseconds) and LV-only pacing. A substudy in 31 patients evaluated the invasive LV+dP/dt(max). The best fusion-optimized AV interval was 136 30milliseconds during atrial sensing and 192 +/- 35milliseconds during atrial pacing. The best QRS was obtained with simultaneous biventricular pacing in 28 patients (37%), LV preexcitation in 22 (29%), LV-only in 20 (26%), and RV preexcitation in 6 (8%). Baseline QRS was shortened more by FOI (59 +/- 19milliseconds) than by nominal settings (40 +/- 21milliseconds; P < 0.001). Sixty-five patients (86%) showed >10% shortening of the baseline QRS with FOI; none prolonged the QRS duration by FOI compared to nominal settings. All echocardiographic asynchrony parameters were corrected by FOI. Baseline+dP/dt(max) improvement was greater in FOI (127 +/- 95 mmHg/seconds) than in nominal settings (102 +/- 71 mmHg/seconds; P= 0.05).ConclusionThe FOI method is feasible, further reduces QRS duration, and improves acute hemodynamic response compared to nominal programming of CRT.