Impact of sleep-disordered breathing treatment on ventricular tachycardia in patients with heart failure

Background: Sleep-disordered breathing (SDB) is a highly common comorbidity in patients with heart failure (HF), and a known risk factor for ventricular tachycardia (VT) development. However, little is known about the impact of SDB treatment on VT burden in HF patients to date. Therefore, this study investigated VT burden, as well as implantable cardioverter-defibrillator (ICD) therapies in HF patients with SDB treatment, in comparison to untreated SDB HF patients. Methods: This retrospective study analyzed VT burden, rate of antitachycardia pacing (ATP), and the number of shocks delivered in a propensity score-matched patient cohort of patients with SDB treatment or control. Patients had moderate or severe SDB (n = 73 per each group; standardized mean difference of 0.08) and were followed for a minimum of one year. In addition, survival over 4 years was assessed. Results: Mean patient age was 67.67 $\pm$ 10.78 and 67.2 $\pm$ 10.10, respectively, with 15.06% and 10.95% of the patients, respectively, being female. Regarding SDB subtypes in the control and SDB treatment group, central sleep apnea was present in 42.46% and 41.09% of the patients, respectively, and obstructive sleep apnea was present in 26.02% and 31.50% of the patients, respectively. Mixed type sleep disorder was present in 31.50% and 27.40% of cases. Among the SDB treatment group, a significantly lower number of VTs (28.8% vs. 68.5%; $\it p$ = 0.01), ATP (21.9% vs. 50.7%; $\it p$ = 0.02), as well as a lower shock rate (5.5% vs. 31.5%; p$\it p$ < 0.01), was observed compared to the control group. Furthermore, the VT burden was significantly lower in the SDB treatment group when compared to the time prior to SDB treatment ($\it p$ = 0.02). Event-free survival was significantly higher in the SDB treatment group (Log-rank $\it p$ < 0.01). Conclusion: SDB treatment in HF patients with ICD leads to significant improvements in VT burden, ATP and shock therapy, and may even affect survival. Thus, HF patients should be generously screened for SDB and treated appropriately

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

Machine-learning-based diagnostics of cardiac sarcoidosis using multi-chamber wall motion analyses

Background: Hindered by its unspecific clinical and phenotypical presentation, cardiac sarcoidosis (CS) remains a challenging diagnosis. Objective: Utilizing cardiac magnetic resonance imaging (CMR), we acquired multi-chamber volumetrics and strain feature tracking for a support vector machine learning (SVM)-based diagnostic approach to CS. Method: Forty-five CMR-negative (CMR(−), 56.5(53.0;63.0)years), eighteen CMR-positive (CMR(+), 64.0(57.8;67.0)years) sarcoidosis patients and forty-four controls (CTRL, 56.5(53.0;63.0)years)) underwent CMR examination. Cardiac parameters were processed using the classifiers of logistic regression, KNN(K-nearest-neighbor), DT (decision tree), RF (random forest), SVM, GBoost, XGBoost, Voting and feature selection. Results: In a three-cluster analysis of CTRL versus vs. CMR(+) vs. CMR(−), RF and Voting classifier yielded the highest prediction rates (81.82%). The two-cluster analysis of CTRL vs. all sarcoidosis (All Sarc.) yielded high prediction rates with the classifiers logistic regression, RF and SVM (96.97%), and low prediction rates for the analysis of CMR(+) vs. CMR(−), which were augmented using feature selection with logistic regression (89.47%). Conclusion: Multi-chamber cardiac function and strain-based supervised machine learning provides a non-contrast approach to accurately differentiate between healthy individuals and sarcoidosis patients. Feature selection overcomes the algorithmically challenging discrimination between CMR(+) and CMR(−) patients, yielding high accuracy predictions. The study findings imply higher prevalence of cardiac involvement than previously anticipated, which may impact clinical disease management

CMR-based right ventricular strain analysis in cardiac amyloidosis and its potential as a supportive diagnostic feature

$\it Background:$ Right ventricular (RV) strain has provided valuable prognostic information for patients with $\underline {cardiac amyloidosis}$ (CA). However, the extent to which RV strain and strain rate can differentiate CA is not yet clinically established. CA underdiagnosis delays treatment strategies and exacerbates patient prognosis. $\it Aims:$ Evaluation of $\underline {cardiac magnetic resonance}$ (CMR) quantified RV global and regional strain of CA and $\underline {HCM}$ patients along with CA subtypes. $\it Methods:$ CMR feature tracking attained longitudinal, radial and circumferential global and regional strain in 47 control subjects (CTRL), 43 CA-, 20 hypertrophic cardiomyopathy- (HCM) patients. CA patients were subdivided in 21 transthyretin-related amyloidosis (ATTR) and 20 acquired immunoglobulin light chain (AL) patients. Strain data and baseline clinical parameters were statistically analysed with respect to $\underline {diagnostic performance}$ and discriminatory power between the different clinical entities. $\it Results:$ Effective differentiation of CA from HCM patients was achieved utilizing global longitudinal (GLS: 16.5 $\pm$ 3.9% vs. −21.3 $\pm$ 6.7%, p = 0.032), radial (GRS: 11.7 $\pm$ 5.3% vs. 16.5 $\pm$ 7.1%, p < 0.001) and circumferential (GCS: -7.6 $\pm$ 4.0% vs. −9.4 $\pm$ 4.4%, p = 0.015) right ventricular strain. Highest strain-based hypertrophic phenotype differentiation was attained using GRS (AUC = 0.86). Binomial regression found right $\underline {ventricular ejection fraction}$ (RV-EF) (p = 0.017) to be a significant predictor of CA-HCM differentiation. CA subtypes had comparable cardiac strains. $\it Conclusion:$ CMR-derived RV global strains and various regional longitudinal strains provide discriminative radiological features for CA-HCM differentiation. However, in terms of feasibility, cine-derived RV-EF quantification may suffice for efficient differential diagnostic support

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

Long-term efficacy and impact on mortality of remote magnetic navigation guided catheter ablation of ventricular arrhythmias

Remote magnetic navigation (RMN) facilitates ventricular arrhythmia (VA) ablation. This study aimed to evaluate the long-term efficacy of RMN-guided ablation for ventricular tachycardia (VT) and premature ventricular contractions (PVC). A total of 176 consecutive patients (mean age 53.23 $\pm$ 17.55 years, 37% female) underwent VA ablation for PVC (132 patients, 75%) or VT (44 patients, 25%). The cohort consisted of 119 patients (68%) with idiopathic VA, 31 (18%) with ischemic (ICM), and 26 (15%) with dilated cardiomyopathy (DCM). VA recurrence was observed in 69 patients (39%, mean age 51.71 $\pm$ 19.91 years, 23% female) during a follow-up period of 5.48 years (first quartile 770.50 days, second quartile 1101.50 days, third quartile 1615.50 days). Left ventricular ejection fraction <40% lead to a significantly increased risk for VA ($\it p$ = 0.031*). Multivariate analyses found DCM to be an independent predictor (IP) for VA recurrence ($\it p$ < 0.001*, hazard ratio (HR) 3.74, confidence interval (CI) 1.58–8.88). ICM resulted in a lower increase in VA recurrence ($\it p$ = 0.221, HR 1.49, CI 0.79–2.81). Class I/III/IV antiarrhythmic drug therapy (AADs) was also identified as IP for recurrence ($\it p$ = 0.030*, HR 2.48, CI 1.11–5.68). A total of 16 patients (9%) died within the observational period. RMN-guided ablation of VA lead to acceptable long-term results. An impaired LV function, DCM, and AADs were associated with a significant risk for VA recurrence. Personalized paths are needed to improve efficacy and outcome