First-in-human high-density epicardial mapping and ablation through a left anterior minithoracotomy in an LVAD patient presenting in electrical storm

$\bf Background$ Despite substantial technical improvements in long-term mechanical circulatory support, ventricular tachycardia (VT) remains a major challenge in left ventricular assist device (LVAD) patients. Recurrent VTs in LVAD patients are not only associated with limited quality of life, but also increased mortality. Although LVAD therapy improves VT tolerance of the left ventricle, haemodynamical deterioration of the right ventricle is the limiting factor in these patients. $\textbf {Case summary}$ We present a case report of a hybrid epicardial VT ablation of incessant VTs in a 53-year-old man with advanced heart failure and St.p. LVAD implantation. With this unique clinical case report, we describe an epicardial VT ablation using secondary surgical open-heart access in a patient with therapy-refractory VTs combing left-sided minithoracotomy with high-density (HD) mapping and catheter ablation. $\bf Discussion$ To the best of our knowledge, the presented approach is the first interdisciplinary case of epicardial VT ablation using secondary surgical open-heart access in an LVAD patient with therapy-refractory VTs. By combing left-sided minithoracotomy with HD mapping and catheter ablation, we could to demonstrate that even in these complex patients epicardial VT ablations can be performed safely and improve quality of life of LVAD patients with recurrent implantable cardioverter-defibrillator shock therapies

Posterior wall substrate modification using optimized and contiguous lesions in patients with atrial fibrillation

$\bf Background:$ Radiofrequency (RF) linear ablation at the left atrial (LA) roof and bottom to isolate the LA posterior wall using contiguous and optimized RF lesions was evaluated. Achieving isolation of the LA posterior wall is challenging as two continuous linear lesion sets are necessary. $\bf Methods:$ Forty consecutive patients with symptomatic atrial fibrillation (AF) and arrhythmia substrates affecting the LA posterior wall underwent posterior wall isolation by linear lesions across the roof and bottom. The cohort was divided into two groups: group 1 (20 patients) linear ablation guided by contact force (CF) only; group 2 (20 patients) guided by ablation index (AI) and interlesion distance. $\bf Results:$ Bidirectional block across the LA roof and bottom was achieved in 40/40 patients. Additional endocardial RF applications in 5 patients from group 1 vs. 3 patients from group 2 resulted in posterior wall isolation in all patients. Procedure duration was almost equal in both groups. CF and AI were significantly higher in group 2 for the roof line, whereas no statistical difference was found for the bottom line. AI-guided LA posterior wall isolation led to a significantly lower maximum temperature increase. The mean AI value as well as the mean value for catheter-to-tissue CF for the roof line were significantly higher when AI-guided ablation was performed. Standard deviation in group 2 showed a remarkably lower dispersion. $\bf Conclusions:$ Ablation index guided posterior wall isolation for substrate modification is safe and effective. AI guided application of the posterior box lesion allows improved lesion formation

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

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

$\bf Background:$ 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. $\bf Methods:$ We analyzed data from 10 consecutive patients who underwent AF ablation using the DT RFA catheter guided by EnSite X. Procedural data and short-term follow-up were assessed as well as potential technical issues. $\bf Results:$ Nine out of 10 patients underwent de-novo pulmonary vein isolation (PVI), and 1 patient underwent repeat ablation. First pass isolation was observed in 7/10 patients. Total procedure duration (skin-to-skin) was 88.9 $\pm$ 30.1 min, and left atrium dwell time was 70 $\pm$ 22.3 min. The mean number of RF applications needed for PVI and additional ablation was 70.52 $\pm$ 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. $\bf Conclusions:$ 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

Two competing cryoballoon technologies for single shot pulmonary vein isolation

Following its introduction into clinical practice, the cryoballoon (CB) has proved to be an alternative for pulmonary vein isolation (PVI) in patients with paroxysmal and persistent atrial fibrillation (AF). In comparison with the standard radiofrequency procedure, the CB method results in a shorter procedure time and learning curve as well as a higher degree of reproducibility. A new cryoballoon (NCB) was recently introduced on the market. In this review, we addressed the following questions: Is the new system technically similar to the previous one? Is there a difference in terms of periprocedural parameters? Are acute success and complication rates similar? Is the learning curve different

Baroreflex activation therapy in advanced heart failure therapy

$\bf Aims$ Baroreflex activation therapy (BAT) is an innovative treatment option for advanced heart failure (HFrEF). We analysed patients' BAT acceptance and the outcome of BAT patients compared with HFrEF patients solely treated with a guideline-directed medical therapy (GDMT) and studied effects of sacubitril/valsartan (ARNI). $\bf Methods$ In this prospective study, 40 HFrEF patients (71 $\pm$ 3 years, 20% female) answered a questionnaire on the acceptance of BAT. Follow-up visits were performed after 3, 6, and 12 months. Primary efficacy endpoints included an improvement in QoL, NYHA class, LVEF, HF hospitalization, NT-proBNP levels, and 6MHWD. $\bf Results$ Twenty-nine patients (73%) showed interest in BAT. Ten patients (25%) opted for implantation. BAT and BAT + ARNI patients developed an increase in LVEF (BAT +10%, $\it P$-value ($\it P$) = 0.005*; BAT + ARNI +9%, $\it P$ = 0.049*), an improved NYHA class (BAT −88%, $\it P$ = 0.014*, BAT + ARNI −90%, $\it P$ = 0.037*), QoL (BAT +21%, $\it P$ = 0.020*, BAT + ARNI +22%, $\it P$ = 0.012*), and reduced NT-proBNP levels (BAT −24%, $\it P$ = 0.297, BAT + ARNI −37%, $\it P$ = 0.297). BAT HF hospitalization rates were lower (50%) compared with control group patients (83%) ($\it P$ = 0.020*). $\bf Conclusions$ Although BAT has generated considerable interest, acceptance appears to be ambivalent. BAT improves outcome with regard to LVEF, NYHA class, QoL, NT-proBNP levels, and HF hospitalization rates. BAT + ARNI resulted in more pronounced effects than ARNI alone

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 $\pm$ 11.6, 31% female) undergoing PVI with the POLARx were compared to a cohort of 531 consecutive patients (63.0 $\pm$ 27.9, 25% female) treated with AFA. Acute PVI was achieved in all patients ($\ n$ = 596, 100%). Total procedure duration (POLARx 113.3 $\pm$ 23.2 min, AFA 100.9 $\pm$ 21.3 min; $\ p$ < 0.001) and fluoroscopy time (POLARx 10.5 $\pm$ 5.9 min, AFA 4.8 $\pm$ 3.6 min; $\ p$ < 0.001) were significantly longer in the POLARx group. The POLARx balloon achieved significantly lower nadir temperatures (POLARx −57.7 $\pm$ 0.9 °C, AFA −45.1 $\pm$ 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

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

$\bf Introduction$ 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 $3^{rd}$ generation LVADs. $\textbf {Methods and results}$ 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 $\pm$ 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 ($\it n$ = 4). Two non-procedure-related deaths occurred during follow-up. $\bf Conclusions$ 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

Find me if you can

Aims: The CARTOFINDER module allows for simultaneous and automated detection of repetitive focal and rotational activations in patients with atrial arrhythmias. This study aimed to validate the CARTOFINDER algorithm for the detection of potential drivers for atrial fibrillation (AF) and to access their potential impact on individual arrhythmia substrates. Methods: Fifty consecutive patients underwent AF ablation for persistent AF (PERS), using a 3D-mapping system with the integrated CARTOFINDER module. Regions of interest (ROIs) were identified before and after ablation, and their spatial and temporal relationship was correlated with areas of fibrosis. Results: Procedural success was achieved in all patients and 42% received ablation beyond pulmonary vein isolation (PVI). AF termination was observed in 6 patients (12%). The mean procedure duration was 134 $\pm$ 29 min. ROIs were revealed in all patients (mean $\it n$ = 77 $\pm$ 52) and there was no statistical evidence for a predilection site. There was no significant anatomical correlation between ROIs and bipolar low voltage. Remapping confirmed the elimination of ROIs in relation to the individual ablation site, a limited reproducibility of rotational ROIs and persistent focal activity over time in some anatomical segments. ROIs were not a predictor for AF recurrence during following ablation. Conclusions: CARTOFINDER mapping can be integrated into a routine workflow for AF ablation. ROIs could be discriminated in all patients and an ablation effect was observed in some patients, whereas persistent activity was found in certain anatomical segments, even after ablation. ROIs might be an additional ablation target when we are able to understand the individual substrate

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 $\pm$ 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 $\pm$ 2.58 years) were assessed. All the patients ($\it n$ = 26, 100%) received daily ICD/CRT-D telemonitoring. In most of the patients (73%, $\it n$ = 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 ($\it n$ = 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% ($\it p$ < 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