The individual relationship between atrial fibrillation sources from CARTOFINDER mapping and atrial cardiomyopathy: the catch me if you can trial

Background Targeting individual sources identified during atrial fibrillation (AF) has been used as an ablation strategy with varying results. Objective Aim of this study was to evaluate the relationship between regions of interest (ROIs) from CARTOFINDER (CF) mapping and atrial cardiomyopathy from late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR). Methods Twenty consecutive patients underwent index catheter ablation for persistent AF (PERS AF). Pre-processed LGE CMR images were merged with the results from CF mapping to visualize harboring regions for focal and rotational activities. Atrial cardiomyopathy was classified based on the four Utah stages. Results Procedural success was achieved in all patients (n = 20, 100%). LGE CMR revealed an intermediate amount of 21.41% ± 6.32% for LA fibrosis. ROIs were identified in all patients (mean no ROIs per patient n = 416.45 ± 204.57). A tendency towards a positive correlation between the total amount of atrial cardiomyopathy and the total number of ROIs per patient (regression coefficient, β = 10.86, p = .15) was observed. The degree of fibrosis and the presence of ROIs per segment showed no consistent spatial correlation (posterior: β = 0.36, p-value (p) = .24; anterior: β = −0.08, p = .54; lateral: β = 0.31, p = 39; septal: β = −0.12; p = .66; right PVs: β = 0.34, p = .27; left PVs: β = 0.07, p = .79; LAA: β = −0.91, p = .12). 12 months AF-free survival was 70% (n = 14) after ablation. Conclusion The presence of ROIs from CF mapping was not directly associated with the extent and location of fibrosis. Further studies evaluating the relationship between focal and rotational activity and atrial cardiomyopathy are mandatory

First clinical experience using the DiamondTemp catheter and a novel omnipolar high-resolution mapping system for atrial fibrillation ablation

Background: The DiamondTemp (DT) radiofrequency ablation (RFA) catheter has been introduced as a new tool for atrial fibrillation (AF) ablation. The new technology allows for temperature-controlled irrigated ablation and real-time lesion assessment. Recently, the EnSite X mapping system became commercially available allowing for omnipolar and ultra-high-resolution mapping. We aimed to assess the feasibility of the new DT RFA catheter in performing AF ablation procedures in conjunction with the novel EnSite X system under routine clinical conditions. Methods: We analyzed data from 10 consecutive patients who underwent AF ablation using the DT RFA guided by EnSite X. Procedural data and short-term follow-up were assessed as well as potential technical issues. Results: Nine out of 10 patients underwent de-novo pulmonary vein isolation (PVI), and one patient underwent repeat ablation. First-pass isolation was observed in 7/10 patients. Total procedure duration (skin-to-skin) was 88.9 ± 30.1 min, and left atrium dwell time was 70 ± 22.3 min. The mean number of RF applications needed for PVI and additional ablation was 70.52 ± 26.70. The HD Grid SE mapping catheter was utilized in 8 patients and the Advisor SE in 2 patients. Bidirectional block of the applied lines was achieved in all patients. No steam pops were observed, and no intraprocedural complications occurred. Conclusions: This first clinical series demonstrated that temperature-controlled irrigated ablation in combination with the novel omnipolar and high-resolution mapping system resulted in rapid, efficient, and durable lesion formation under routine clinical conditions. Randomized controlled trials are needed to elucidate the impact on lesion formation, long-term outcomes, and reproducibility of our initial findings

When dystrophia meets ischaemia

$\bf Background$ This case reviews the cardiac involvement of myotonic dystrophy type 2 in terms of ventricular arrhythmias (VAs) and individual myocardial scar formation as target for catheter ablation. $\textbf {Case summary}$ A 62-year-old woman with myotonic dystrophy type 2 and a severely reduced left ventricular ejection fraction (25%) presented with recurrent episodes of VAs and consecutive implantable cardioverter-defibrillator therapies. The patient already underwent two VA ablation attempts focusing on an ischaemia-related arrhythmia substrate in the left ventricle. The patient was scheduled for repeat ablation after the progression of coronary artery disease was ruled out. Interestingly bipolar voltage as well as activation mapping revealed an arrhythmia substrate along with the basal and inferior aspects of the right ventricle (RV). Catheter ablation of this scarred area in the RV resulted in specific termination of the VAs. Due to end-stage heart failure, key heart transplant criteria were met. The patient was evaluated for heart transplantation and added to the waiting list. Hitherto, no further VAs were documented during follow-up. $\bf Discussion$ As these patients present with specific dystrophia-related arrhythmia substrates, we propose pre-procedural visualization of dystrophy-associated arrhythmia substrates using cardiac magnetic resonance imaging allowing for personalized ablation approaches in these patients

Combination of High-Density and Coherent Mapping for Ablation of Ventricular Arrhythmia in Patients with Structural Heart Disease

The present study describes our experience with a new mapping approach for ventricular arrhythmia (VA) ablation in patients with structural heart disease (SHD). Consecutive patients undergoing catheter ablation for recurrent VA were analyzed. High-density mapping was conducted in all patients. In patients with inducible VA, local activation time (LAT) mapping and a novel vector-based mapping algorithm were implemented to analyze arrhythmia propagation. In case of focal tachycardia, the location of earliest activation was targeted. In VAs with re-entrant mechanisms, zones of slow conduction based on coherent mapping were ablated. Substrate modification was performed when pathologic electrograms were identified. Seventy-four patients were included. Sixty-five patients (87.8%) were male. Ischemic cardiomyopathy was the underlying disease in 35 patients (47.3%) and nonischemic cardiomyopathy was the underlying disease in 39 patients (52.7%). Mean left ventricular ejection fraction was 33.8 ± 9.9%. Non-inducibility of any VA was achieved in 70 patients (94.6%). Termination of VA was achieved in 93.5% of patients with stable VA. In 4 patients (5.4%), partial success was achieved. VA (p < 0.001), ATP (p < 0.001) and shock burden (p = 0.001) were significantly reduced after ablation. Mean arrhythmia-free survival after 12 months was 85.1 ± 4.7%. High-density mapping in combination with coherent mapping may facilitate the understanding of the tachycardia mechanism, providing targets for effective ablation

Lessons learned from catheter ablation of ventricular arrhythmias in patients with a fully magnetically levitated left ventricular assist device

Introduction!#!Data on catheter ablation of ventricular arrhythmias (VA) are scarce in patients with left ventricular assist devices (LVADs) and current evidence predominantly consists of case reports with outdated LVAD. This prospective observational study reports our experience in terms of catheter ablation of VAs in patients with novel 3!##!Methods and results!#!Between 2018 and 2020, nine consecutive patients undergoing a total number of ten ablation procedures for VAs were analyzed. The mean duration between LVAD implantation and catheter ablation was 23 ± 16 months. Acute procedural success was achieved in all patients. VA substrates were not related to the LVAD scarring (cannula) site in the majority of patients. All procedures were conducted without any relevant procedure-related complications. In terms of follow-up, only one patient presented with a repeat episode of electrical storm requiring ICD-shocks 16 months after the initial ablation procedure. Four patients suffered of singular VA effectively treated with antitachycardia pacing via their ICD. The remainder were free of any VA relapse (n = 4). Two non-procedure-related deaths occurred during follow-up.!##!Conclusions!#!Catheter ablation of VAs in patients with 3rd generation LVAD is feasible and leads to satisfying clinical results in terms of freedom from VA recurrence and quality of life. The majority of arrhythmia substrates in these patients are not directly related to the LVAD cannulation site and may represent a progress of heart failure

News from the Cold Chamber: Clinical Experiences of POLARx versus Arctic Front Advance for Single-Shot Pulmonary Vein Isolation

Cryoballoon (CB)-guided pulmonary vein isolation (PVI) represents a cornerstone in the treatment of atrial fibrillation (AF). Recently, a novel balloon-guided single shot device (POLARx, Boston Scientific) was designed. Our study aimed to compare the efficacy, safety and characteristics of the novel CB system with the established one (Arctic Front Advance (Pro), AFA, Medtronic). A total number of 596 patients undergoing CB-guided ablation for AF were included. 65 patients (65.0 ± 11.6, 31% female) undergoing PVI with the POLARx were compared to a cohort of 531 consecutive patients (63.0 ± 27.9, 25% female) treated with AFA. Acute PVI was achieved in all patients (n = 596, 100%). Total procedure duration (POLARx 113.3 ± 23.2 min, AFA 100.9 ± 21.3 min; p < 0.001) and fluoroscopy time (POLARx 10.5 ± 5.9 min, AFA 4.8 ± 3.6 min; p < 0.001) were significantly longer in the POLARx group. The POLARx balloon achieved significantly lower nadir temperatures (POLARx −57.7 ± 0.9 °C, AFA −45.1 ± 2.6 °C; p < 0.001) and a significantly higher percentage of pulmonary veins successfully isolated with the first freeze (p = 0.027 *). One major complication occurred in the POLARx (2%) and three (1%) in the AFA group. Both ablation systems are comparably safe and effective. AF ablation utilizing the POLARx system is associated with longer procedure and fluoroscopy times as well as lower nadir temperatures

Magnetic-Resonance-Imaging-Based Left Atrial Strain and Left Atrial Strain Rate as Diagnostic Parameters in Cardiac Amyloidosis

Aims: The present study aims to evaluate magnetic-resonance-imaging (MRI)-assessed left atrial strain (LAS) and left atrial strain rate (LASR) as potential parameters for the diagnosis of cardiac amyloidosis (CA), the distinction of clinical subtypes and differentiation from other cardiomyopathies. Methods and results: LAS and LASR were assessed by MRI feature tracking in patients with biopsy-proven CA. LAS and LASR of patients with CA were compared to healthy subjects and patients with hypertrophic cardiomyopathy. LAS and LASR were also analyzed concerning differences between patients with transthyretin (ATTR) and light chain amyloidosis (AL). A total of 44 patients with biopsy-proven CA, 19 patients with hypertrophic cardiomyopathy and 24 healthy subjects were included. In 22 CA patients (50%), histological examination identified ATTR as CA subtype and AL in the remaining patients. No significant difference was observed for reservoir, conduit or booster LAS in patients with AL or ATTR. Reservoir LAS, conduit LAS and booster LAS were significantly reduced in patients with CA and HCM as compared to healthy subjects (p < 0.001). Reservoir LAS and booster LAS were significantly reduced in CA as compared to HCM patients (p < 0.001). A linear correlation was observed between LA global reservoir strain and LA-EF (p < 0.001, r = 0.5), conduit strain and global longitudinal LV strain (p < 0.001, r = 0.5), global booster strain rate and LA-EF (p < 0.001, r = 0.6) and between global booster strain rate and LA area at LVED (p < 0.0001, 0.5). Conclusions: LAS and LASR are severely impaired in patients with CA. The MRI-based assessment of LAS and LASR might allow non-invasive diagnosis and categorization of CA and its distinct differentiation from other hypertrophic phenotypes

The Role of Daily Implant-Based Multiparametric Telemonitoring in Patients with a Ventricular Assist Device

The telemonitoring of heart failure (HF) patients is becoming increasingly important. This study aimed to evaluate the benefit of telemonitoring in end-stage HF patients with a ventricular-assistance device (VAD). A total of 26 HF-patients (66 ± 11 years, 88% male) on VAD therapy with an implantable cardioverter-defibrillator (ICD) or a cardiac resynchronization defibrillator (CRT-D) including telemonitoring function were enrolled. The long-term follow-up data (4.10 ± 2.58 years) were assessed. All the patients (n = 26, 100%) received daily ICD/CRT-D telemonitoring. In most of the patients (73%, n = 19), the telemedical center had to take action for a mean of three times. An acute alert due to sustained ventricular arrhythmias (VAs) occurred in 12 patients (63%) with 50% of them (n = 6) requiring ICD shock delivery. Eight patients (67%) were hospitalized due to symptomatic VAs. In 11 patients (92%), immediate medication adjustments were recommended. Relevant lead issues were revealed in thirteen patients (50%), with six patients (46%) undergoing consecutive lead revisions. Most of the events (83%) were detected within 24 h. Daily telemonitoring significantly reduced the number of in-hospital device controls by 44% (p < 0.01). The telemonitoring ensured that cardiac arrhythmias and device/lead problems were identified early, allowing pre-emptive and prompt interventions. In addition, the telemonitoring significantly reduced the number of in-hospital device controls in this cohort of HF patients

Catheter ablation in patients with ventricular fibrillation by purkinje de-networking

$\bf Background:$ Ventricular fibrillation (VF) is a leading cause of cardiovascular death worldwide. However, recurrence rates of arrhythmia are high leading to mortality and morbidity. Recently, Purkinje fibers have been identified as potential sources of VF initiation and maintenance. $\bf Aim:$ The study analyzes the feasibility and effectiveness of catheter ablation in patients with recurrent VF by specific Purkinje de-networking (PDN). \ud $\bf Methods:$ Consecutive patients with recurrent VF undergoing PDN were included in this observational study. The procedural endpoint was the non-inducibility of sustained ventricular arrhythmia. A three-dimensional -anatomical mapping was conducted, and the specific cardiac conduction system and Purkinje fibers were tagged. All detectable Purkinje signals were ablated in the left ventricle (LV). Additional right ventricular (RV) PDN was performed in case of VF inducibility after LV ablation. Follow-up was performed by patient visits at our outpatient clinic including device interrogation and by telephone interviews. $\bf Results:$ Eight patients were included in the study. Six patients were females (75%); the median age during the procedure was 43 [37;57] years and the median body mass index was 24 [23;33] $kg/m^{2}$. Four patients (50%) had known structural heart disease with two cases of ischemic cardiomyopathy and two cases of dilated cardiomyopathy. In four patients (50%), no underlying structural heart disease could be identified. The median LV ejection fraction was 42 $\pm$ 16.4%. All patients had an implantable cardioverter-defibrillator (ICD) prior to ablation with documentation of recurrent VF. The median number of ICD shocks before the ablation was 5 [3;7]. LV PDN was performed in all patients. In two patients (25%), an additional RV PDN was performed. Non-inducibility of any ventricular arrhythmia was achieved in all patients after PDN. Two patients showed complete left bundle branch block post-ablation. The median follow-up duration was 264 [58;421] days. Two patients (25%) experienced ventricular arrhythmia recurrence with recurrent ICD-shock delivery. One patient died during follow-up with an unknown cause of death. Six patients (75%) experienced no arrhythmia recurrence during follow-up. $\bf Conclusion:$ Purkinje de-networking represents a novel treatment option for patients with recurrent VF without arrhythmia substrate or specific arrhythmia triggers with promising results in terms of efficiency and feasibility. Larger and more prospective studies are needed for a systematic evaluation