Incidence and predictors of thermal oesophageal and vagus nerve injuries in Ablation Index-guided high-power-short-duration ablation of atrial fibrillation: a prospective study

AIMS

High-power-short-duration (HPSD) ablation is an effective treatment for atrial fibrillation but poses risks of thermal injuries to the oesophagus and vagus nerve. This study aims to investigate incidence and predictors of thermal injuries, employing machine learning.

METHODS AND RESULTS

A prospective observational study was conducted at Leipzig Heart Centre, Germany, excluding patients with multiple prior ablations. All patients received Ablation Index-guided HPSD ablation and subsequent oesophagogastroduodenoscopy. A machine learning algorithm categorized ablation points by atrial location and analysed ablation data, including Ablation Index, focusing on the posterior wall. The study is registered in clinicaltrials.gov (NCT05709756). Between February 2021 and August 2023, 238 patients were enrolled, of whom 18 (7.6%; nine oesophagus, eight vagus nerve, one both) developed thermal injuries, including eight oesophageal erythemata, two ulcers, and no fistula. Higher mean force (15.8 ± 3.9 g vs. 13.6 ± 3.9 g, P = 0.022), ablation point quantity (61.50 ± 20.45 vs. 48.16 ± 19.60, P = 0.007), and total and maximum Ablation Index (24 114 ± 8765 vs. 18 894 ± 7863, P = 0.008; 499 ± 95 vs. 473 ± 44, P = 0.04, respectively) at the posterior wall, but not oesophagus location, correlated significantly with thermal injury occurrence. Patients with thermal injuries had significantly lower distances between left atrium and oesophagus (3.0 ± 1.5 mm vs. 4.4 ± 2.1 mm, P = 0.012) and smaller atrial surface areas (24.9 ± 6.5 cm2 vs. 29.5 ± 7.5 cm2, P = 0.032).

CONCLUSION

The low thermal lesion's rate (7.6%) during Ablation Index-guided HPSD ablation for atrial fibrillation is noteworthy. Machine learning based ablation data analysis identified several potential predictors of thermal injuries. The correlation between machine learning output and injury development suggests the potential for a clinical tool to enhance procedural safety.

Cryocure-VT: the safety and effectiveness of ultra-low-temperature cryoablation of monomorphic ventricular tachycardia in patients with ischaemic and non-ischaemic cardiomyopathies

AIMS

The ultra-low-temperature cryoablation (ULTC) ablation system using -196°C N2 cryogen has been reported to create lesions with freeze duration-dependent depth titratable to over 10 mm with minimum attenuation by scar. Cryocure-VT (NCT04893317) was a first-in-human clinical trial evaluating the safety and efficacy of a novel, purpose-built ULTC catheter in endocardial ablation of scar-dependent ventricular tachycardias (VTs).

METHODS AND RESULTS

This prospective, multi-centre study enrolled patients referred for de novo or second ablations of recurrent monomorphic VT of both ischaemic and non-ischaemic aetiologies. Primary safety and efficacy endpoints of the study were freedom from device- or procedure-related major adverse events (MAEs) up to 30 days post-ablation, acute non-inducibility of clinical VTs at the end of the procedure, and freedom from sustained VT or implantable defibrillator intervention at 6 months. Ultra-low-temperature cryoablation was performed in 64 patients (age 67 ± 11 years, 78% ischaemic, ejection fraction = 35 ± 10%) at 9 centres. The primary acute effectiveness endpoint was achieved in 94% (51/54) of patients in whom post-ablation induction was attempted. There were no protocol-defined MAEs; four procedure-related serious adverse events resolved without clinical sequelae. At 6-month follow-up, 38 patients (60.3%) remained VT-free, and freedom from defibrillator shock was 81.0%, with no significant difference between ischaemic and non-ischaemic cohorts. In 47 patients with defibrillator for at least 6 months prior to the ablation, the VT burden was reduced from median of 4, inter-quartile range (IQR, 1-9) to 0, IQR (0-2).

CONCLUSION

In this first-in-human multi-centre experience, endocardial ULTC ablation of monomorphic VT appears safe and effective in patients with both ischaemic-cardiomyopathy and non-ischaemic-cardiomyopathy.

CLINICAL TRIAL REGISTRATION

NCT04893317.

Single catheter approach for treatment of premature ventricular contractions

BACKGROUND

Catheter ablation has become one of the main treatment strategies in patients with premature ventricular complexes (PVC). The successful mapping and ablation can be performed with an ablation catheter without additional diagnostic catheters.

HYPOTHESIS

We hypothesize that using a single catheter for PVC ablation may decrease complications, procedure time, and fluoroscopy exposure while maintaining comparable success rates.

METHODS

Sixty-nine consecutive patients with PVC were treated with a single catheter approach compared to a historical cohort, in which a conventional setup was used. Propensity score matching was conducted with a 1:1 ratio. Outcome parameters included acute procedural success with elimination of all premature ventricular contractions after catheter ablation, procedural data as well as complication rates.

RESULTS

Patients treated with a single catheter approach had shorter total procedure (60 minutes [IQR: 47,5-69,0 minutes] vs. 90 minutes [IQR 60-120 minutes]; p = 0.001) and fluoroscopy times (218 seconds [IQR: 110,5-446 seconds] vs. 310 seconds [IQR 190-640 seconds]; p = 0.012), which consecutively leads to a reduction of radiation exposure signified by a lower dose area product (155 cGycm² [IQR 74.4-334.5 cGycm²] vs. 368.4 cGycm² [IQR: 126-905.4 cGycm²]; p value 0.009). Acute procedural success rates were comparable in both groups (54 [84.3%] in the single catheter approach group and 58 [90.6%] in the conventional group; p: 0.287).

CONCLUSION

A single catheter approach for the treatment of PVC is associated with a reduction of procedure- and fluoroscopy time, as well as a lesser radiation exposure, while maintaining equivalent acute success and complication rates compared with a conventionally used catheter setup.

Impact of repeat ablation of ventricular tachycardia in patients with structural heart disease

AIMS

Recurrences of ventricular tachycardia (VT) after initial catheter ablation is a significant clinical problem. In this study, we report the efficacy and risks of repeat VT ablation in patients with structural heart disease (SHD) in a tertiary single centre over a 7-year period.

METHODS AND RESULTS

Two hundred ten consecutive patients referred for repeat VT ablation after previous ablation in our institution were included in the analysis (53% ischaemic cardiomyopathy, 91% males, median age 65 years, mean left ventricular ejection fraction 35%). After performing repeat ablation, the clinical VTs were acutely eliminated in 82% of the patients, but 46% of the cohort presented with VT recurrence during the 25-month follow-up. Repeat ablation led to a 73% reduction of shock burden in the first year and 61% reduction until the end of follow-up. Similarly, VT burden was reduced 55% in the first year and 36% until the end of the study. Fifty-two patients (25%) reached the combined endpoint of ventricular assist device implantation, heart transplantation, or death. Advanced New York Heart Association functional class, anteroseptal substrate, and periprocedural complication after repeat ablation were associated with worse prognosis independently of the type of cardiomyopathy.

CONCLUSION

While complete freedom from VT after repeat ablation in SHD was difficult to achieve, ablation led to a significant reduction in VT and shock burden. Besides advanced heart failure characteristics, anteroseptal substrate and periprocedural complications predicted a worse outcome.

Probing site-selective doping and charge compensating defects in KMgF3: insights from a hybrid DFT study

Design of optoelectronic materials with tunable properties using activators and defect clusters has become one of the prime interests of current research. In this study, detailed Density Functional Theory based calculations have been presented to investigate the geometries and electronic structures of various possible defect clusters using Eu-KMgF3 as a probe which has numerous technological and industrial applications. Using a more reliable hybrid density functional, we have calculated defect formation energies and thermodynamic transition levels to get knowledge about the site selectivity of Eu. It has been observed that the electronic structure of Eu-KMgF3 is not only dependent on the site of doping but also on the oxidation state of Eu (2+/3+). The present study also investigates the relative stability of different kinds of defects and defect clusters under various synthetic growth conditions. The ultimate aim is to find out the microscopic origin of the fundamental optical properties of Eu-KMgF3 and provide an unambiguous explanation of available experimental results. Thus, it has been revealed that doping with Eu results in the spontaneous formation of intrinsic defects, which contribute to the observed optical behaviour. We have also extended our study to investigate the role of codoping with Li in determining the geometry and electronic structure of Eu-KMgF3 aiming to explain its impact on the optical properties. Thus, a complete presentation of the influence of the activator in the absence and presence of lattice defects on the optical properties of KMgF3 has been accomplished in the current study. We strongly believe that the present study will be helpful in designing tunable phosphor materials by a defect-controlled synthesis strategy.

Effectiveness of conduction system pacing for cardiac resynchronization therapy: A systematic review and network meta-analysis

INTRODUCTION

Cardiac resynchronization therapy (CRT) with biventricular pacing (BiV-CRT) is ineffective in approximately one-third of patients. CRT with Conduction system pacing (CSP-CRT) may achieve greater synchronization. We aimed to assess the effectiveness of CRT with His pacing (His-CRT) or left bundle branch pacing (LBB-CRT) in lieu of biventricular CRT.

METHODS AND RESULTS

The PubMed, Embase, Web of Science, Scopus, and the Cochrane Library were systematically searched until August 19, 2023, for original studies including patients with reduced left ventricular ejection fraction (LVEF) who received His- or LBB-CRT, that reported either CSP-CRT success, LVEF, QRS duration (QRSd), or New York Heart Association (NYHA) classification. Effect measures were compared with frequentist network meta-analysis. Thirty-seven publications, including 20 comparative studies, were included. Success rates were 73.5% (95% CI: 61.2-83.0) for His-CRT and 91.5% (95% CI: 88.0-94.1) for LBB-CRT. Compared to BiV-CRT, greater improvements were observed for LVEF (mean difference [MD] for His-CRT +3.4%; 95% CI [1.0; 5.7], and LBB-CRT: +4.4%; [2.5; 6.2]), LV end-systolic volume (His-CRT:17.2mL [29.7; 4.8]; LBB-CRT:15.3mL [28.3; 2.2]), QRSd (His-CRT: -17.1ms [-25.0; -9.2]; LBB-CRT: -17.4ms [-23.2; -11.6]), and NYHA (Standardized MD [SMD]: His-CRT:0.4 [0.8; 0.1]; LBB-CRT:0.4 [-0.7; -0.2]). Pacing thresholds at baseline and follow-up were significantly lower with LBB-CRT versus both His-CRT and BiV-CRT. CSP-CRT was associated with reduced mortality (R = 0.75 [0.61-0.91]) and hospitalizations risk (RR = 0.63 [0.42-0.96]).

CONCLUSION

This study found that CSP-CRT is associated with greater improvements in QRSd, echocardiographic, and clinical response. LBB-CRT was associated with lower pacing thresholds. Future randomized trials are needed to determine CSP-CRT efficacy.

Evidence of vacancy ordered structures in PuO2-x and AmO2-x from first-principles calculations

A combination of first-principles calculations and cluster expansion method is used to study ordering of oxygen vacancies in PuO_2-x and AmO_2-x. Vacancy ordered stable/metastable structures of composition Pu₈O₁₅ (PuO_1.875), Pu₆O₁₁ (PuO_1.833), Pu₈O₁₄ (PuO_1.75) and Am₁₀O₁₉ (AmO_1.90), Am₈O₁₅ (AmO_1.875), Am₁₀O₁₈ (AmO_1.80), Am₈O₁₃ (AmO_1.625) are identified in PuO_2-x and AmO_2-x, respectively, from cluster expansion calculations. A comparison of formation enthalpies of vacancy ordered and vacancy disordered structures shows that Am₈O₁₅ (AmO_1.875) and Am₈O₁₃ (AmO_1.625) are more stable by 52 and 55 meV per atom, respectively, compared to their disordered counterparts. Similarly, vacancy ordered Pu₈O₁₅ (PuO_1.875) and Pu₈O₁₄ (PuO_1.75) structures are more stable compared to the disordered structures by 10 and 8 meV per atom, respectively. In contrast, the disordered PuO_1.625 structure is more stable compared to the cluster expansion generated structures. The vacancy ordered structures are mechanically stable and their bulk modulus, Young's modulus, shear modulus and Poisson's ratio are reported.

Cardiac tamponade complicating ventricular arrhythmia ablation: Real life data on incidence, management, and outcome

BACKGROUND AND OBJECTIVE

Cardiac tamponade during ablation procedures is a life-threatening complication. While the incidence and management of tamponade in atrial fibrillation ablation have been extensively described, the data on tamponade during ventricular ablations are very limited. The purpose of this study is to shed light on the incidence, typical perforation sites, and optimal management as observed through real-life data in a tertiary referral center for ventricular ablation.

METHODS AND RESULTS

Consecutive patients with structural heart disease undergoing ventricular tachycardia ablation from 2008-2020 were analyzed. Of the 1078 patients undergoing 1287 ventricular ablation procedures, 20 procedures (1.5%) were complicated by cardiac tamponade. In all but one patient, the tamponade was treated with emergent pericardial drainage, while nine patients eventually underwent surgical repair. The perforation occurred during transseptal or subxiphoid puncture in six patients, during ventricle mapping in two patients, and during ablation in five patients (predominantly basal left ventricle). Steam pop as definite perforation cause could only be established in two patients. Regardless of the management of the complication, all patients survived to discharge.

CONCLUSION

Cardiac tamponade during ventricular ablation occurred in 1.5% of the procedures. In nine patients cardiac repair was necessary. Perforation was mostly associated with subxiphoid puncture or ablation of the basal left ventricle.

P-wave duration and atrial fibrillation recurrence after catheter ablation: a systematic review and meta-analysis

AIMS

Atrial fibrillation (AF) is a global health problem with high morbidity and mortality. Catheter ablation (CA) can reduce AF burden and symptoms, but AF recurrence (AFr) remains an issue. Simple AFr predictors like P-wave duration (PWD) could help improve AF therapy. This updated meta-analysis reviews the increasing evidence for the association of AFr with PWD and offers practical implications.

METHODS AND RESULTS

Publication databases were systematically searched and cohort studies reporting PWD and/or morphology at baseline and AFr after CA were included. Advanced interatrial block (aIAB) was defined as PWD ≥ 120 ms and biphasic morphology in inferior leads. Random-effects analysis was performed using the Review Manager 5.3 and R programs after study selection, quality assessment, and data extraction, to report odds ratio (OR) and confidence intervals. : Among 4175 patients in 22 studies, 1138 (27%) experienced AFr. Patients with AFr had longer PWD with a mean pooled difference of 7.8 ms (19 studies, P < 0.001). Pooled OR was 2.04 (1.16-3.58) for PWD > 120 ms (13 studies, P = 0.01), 2.42 (1.12-5.21) for PWD > 140 ms (2 studies, P = 0.02), 3.97 (1.79-8.85) for aIAB (5 studies, P < 0.001), and 10.89 (4.53-26.15) for PWD > 150 ms (4 studies, P < 0.001). There was significant heterogeneity but no publication bias detected.

CONCLUSION

P-wave duration is an independent predictor for AF recurrence after left atrium ablation. The AFr risk is increasing exponentially with PWD prolongation. This could facilitate risk stratification by identifying high-risk patients (aIAB, PWD > 150 ms) and adjusting follow up or interventions.

Clinical Outcomes in Patients With Dilated Cardiomyopathy and Ventricular Tachycardia

BACKGROUND

Recurrent ventricular tachycardia (VT) due to dilated cardiomyopathy (DCM) is difficult to treat, and long-term outcome data are limited.

OBJECTIVES

The aim of this study was to identify predictors of mortality or heart transplantation (HTx) and VT recurrence.

METHODS

Consecutive patients with DCM accepted for radiofrequency catheter ablation (RFCA) of VT at 9 centers were prospectively enrolled and followed.

RESULTS

Of 281 consecutive patients (mean age 60 ± 13 years, 85% men, mean left ventricular ejection fraction [LVEF] 36% ± 12%), 35% had VT storm, 20% had incessant VT, and amiodarone was unsuccessful in 68%. During follow-up of 21 months (IQR: 6-30 months), 67 patients (24%) died or underwent HTx, and 138 (49%) had VT recurrence (45 within 30 days, defined as early); the 4-year rate of VT recurrence or mortality or HTx was 70%. Independent predictors of mortality or HTx were early VT recurrence (HR: 2.92; 95% CI: 1.37-6.21; P < 0.01), amiodarone at discharge (HR: 3.23; 95% CI: 1.43-7.33; P < 0.01), renal dysfunction (HR: 1.92; 95% CI: 1.01-3.64; P = 0.046), and LVEF (HR: 1.36; 95% CI: 1.0-1.84; P = 0.052). LVEF ≤32% identified patients at risk for mortality or HTx (area under the curve: 0.75). Mortality or HTx per 100 person-years was 40.4 events after early, compared with 14.2 events after later VT recurrence and 8.5 events with no VT recurrence after RFCA (P < 0.01 for both). Patients with early recurrence and LVEFs ≤32% had a 1-year rate of mortality or HTx of 55%. VT recurrence was predicted by prior implantable cardioverter-defibrillator shocks, basal anteroseptal VT origin, and procedural failure but not LVEF.

CONCLUSIONS

Patients with DCM needing RFCA for VT are a high-risk group. Following RFCA, approximately one-half remain free of VT recurrence. Early VT recurrence with LVEF ≤32% identifies those at very high risk for mortality or HTx, and screening for mechanical support or HTx should be considered. Late VT recurrence after RFCA does not predict worse outcome.

Outcomes following cardiac sympathetic denervation in patients with structural heart disease and refractory ventricular arrhythmia

Aim

Cardiac sympathetic denervation (CSD) has been introduced as a bailout therapy in patients with structural heart disease and refractory ventricular arrhythmias (VAs), but available data are scarce. Purpose of this study was to estimate immediate results, complications, and mid-term outcomes of CSD following recurrent VA after catheter ablation.

Methods and results

Adult patients who underwent CSD in the Heart Center Leipzig from March 2017 to February 2021 were retrospectively analysed. Follow-up (FU) was executed via implantable cardioverter defibrillator (ICD) interrogation, telephone interviews, and reviewing medical records. Twenty-one patients (age 63.7 ± 14.4 years, all men, 71.4% non-ischaemic cardiomyopathy, left ventricular ejection fraction 31.6 ± 12.6%) received CSD via video-assisted thoracoscopic surgery (90.5% bilateral, 9.5% left-sided only). Indication for CSD was monomorphic ventricular tachycardia in 76.2% and ventricular fibrillation in 23.8 with 71.4% of patients presenting with electrical storm before index hospitalization. Procedure-related major complications occurred in 9.5% of patients. In-hospital adverse events not related to surgery were common (28.6%) and two patients died during the index hospital stay. During FU (mean duration 9.1 ± 6.5 months), five more patients died. Of the remaining patients, 38.5 and 76.9% were free from any VA or ICD shocks, respectively.

Conclusions

The CSD showed additional moderate efficacy to suppress VAs, when performed as a bailout therapy after previously unsuccessful catheter ablation. At 9 months, it was associated with freedom of ICD shocks in two-thirds of patients. In a population with many comorbidities, the rate of CSD-related complications was acceptable, although there was an overall high risk of procedure unrelated adverse events and death.

A randomized trial of non-fasting vs. fasting for cardiac implantable electronic device procedures (Fast-CIED Study)

AIMS

Data on safety and efficacy of a non-fasting strategy in minimal invasive cardiac procedures are lacking. We assessed a non-fasting strategy compared with a fasting strategy regarding patient's well-being and safety in elective cardiac implantable electronic device (CIED) procedures.

METHODS AND RESULTS

In this randomized, single-blinded clinical trial, 201 patients (non-fasting = 100, fasting = 101) with a mean age of 72.0 ± 11.6 years (66.7% male) were assigned to a non-fasting strategy (solids/fluids allowed up to 1 h) or a fasting strategy (at least 6 h no solids and 2 h no fluids) before the procedure and analysed on an intention-to-treat basis. The co-primary outcomes were patients' well-being scores (based on numeric rating scale, 0-10) and incidence of intra-procedural food-related adverse events, including vomiting, perioperative pulmonary aspiration, and emergency intubation. Renal, haematological, and metabolic blood parameters and 30-day follow-up data were gathered. The summed pre-procedural patients' well-being score was significantly lower in the non-fasting group [non-fasting: 13.1 ± 9.6 vs. fasting: 16.5 ± 11.4, 95% confidence interval (CI) of mean difference (MD) -6.35 to -0.46, P = 0.029], which was mainly driven by significantly lower scores for hunger and tiredness in the non-fasting group (non-fasting vs. fasting; hunger: 0.9 ± 1.9 vs. 3.1 ± 3.2, 95% CI of MD -2.86 to -1.42, P < 0.001; tiredness: 1.6 ± 2.3 vs. 2.6 ± 2.7, 95% CI of MD -1.68 to -0.29, P = 0.023). No intra-procedural food-related adverse events were observed. Relevant blood parameters and 30-day follow-up did not show significant differences.

CONCLUSION

These results showed that a non-fasting strategy is beneficial to a fasting one regarding patient's well-being and comparable in terms of safety for CIED procedures (NCT04389697).

P-wave duration and atrial fibrillation recurrence after catheter ablation, a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is a global health problem with high morbidity and mortality. Catheter ablation (CA) can reduce AF burden and symptoms, but AF recurrence (AFr) remains an issue. Simple AFr predictors like P-wave duration (PWD) could help improve AF therapy.

Purpose

This updated meta-analysis reviews the increasing evidence for the association of AFr with PWD and offers practical implications.

Methods

Publication databases were systematically searched and cohort studies reporting PWD and/or morphology at baseline and AFr after CA were included. Complete interatrial block (cIAB) was defined as PWD≥120 ms and biphasic morphology in inferior leads. Random-effects analysis was performed using the Review Manager 5.3 and R programs after study selection, quality assessment and data extraction, to report odds ratio (OR) and confidence intervals (CI).

Results

Among 4175 patients in 22 studies, 1138 (27%) experienced AFr. Patients with AFr had longer PWD with a mean pooled difference of 7.8 ms (19 studies, p&lt;0.001)(Figure 1). Pooled OR was 2.04 (1.16-3.58) for PWD&gt;120 ms (13 studies, p=0.01), 2.42 (1.12-5.21) for PWD&gt;140 ms (2 studies, p=0.02), 3.97 (1.79-8.85) for cIAB (6 studies, p&lt;0.001) and 10.89 (4.53-26.15) for PWD&gt;150 ms (2 studies, p&lt;0.001)(Figure 2). There was significant heterogeneity but no publication bias detected.

Conclusion

PWD is an independent predictor for AF recurrence after LA ablation. The AFr risk is increasing exponentially with PWD prolongation. This could facilitate risk-stratification by identifying high-risk patients (cIAB, PWD&gt;150 ms) and adjusting follow-up or interventions.

Pacing electrodes to ablate, not to pace: what settings to use to create lesions even deep in the septum

Funding Acknowledgements

Type of funding sources: None.

Background

Intramural septal ventricular arrhythmia remains challenging, requiring emergent technologies and experimental approaches. Although conduction system pacing (CSP) has allowed us to reach deep in the septum, ablation though pacing electrodes has not been examined yet.

Purpose

To evaluate lesion creation by radiofrequency ablation (RFA) through pacing electrodes.

Methods

A custom ex vivo swine model in a saline bath with an indifferent electrode was used to apply RFA with an 8 mm non-irrigated catheter (SJM, MN, USA) on the proximal end of pacing (CapSureFix 5086) or CSP-electrodes (SelectSecure 3830, Medtronic, MN, USA), screwed in perpendicularly to the slab. A generator (Ampere, SJM, MN, USA) applied RFA at varying settings (1-10 W, 1-20 sec). Lesion depth (D), width (W) and volume (V=3,14*W2*D/4) were assessed and analyzed (SPSS 23).

Results

A total of 80 lesions were used for analysis. Median RFA with 3 W over 6 sec resulted in an impedance drop from 200 to 140 Ω and a lesion of 2x3 mm or 9.4 mm3 (Figure 1). Higher energy settings caused impedance rise with abort (n=3, 4%) or charring (n=3, 4%). Compared to conventional electrodes, lesions with CSP-electrodes had similar volume (9.3±7 vs. 10.8±9 mm3, p=0.45) and width (2±0.8 vs. 2±0.7, p=0.58), but more depth (2.6±0.5 vs. 3±0.6, p=0.0.01). Regression analysis showed final-impedance (FI), power and duration (WS=W*Sec) as independent predictors of lesion volume (V=4.7WS-4.1WS2+4.5FI-4, p&lt;0.001).

Conclusions

Effective ablation through pacing electrodes is possible, but lesion size is limited and low-power settings are necessary. Using CSP-electrodes for effective intramural lesions is possibly a new tool for septal arrhythmias. Further in vivo studies are warranted and bailout use should be considered.

Effects of positive endomyocardial biopsy on the survival and the outcomes of catheter ablation of ventricular tachycardia in patients with cardiac sarcoidosis

Funding Acknowledgements

Type of funding sources: Private hospital(s). Main funding source(s): Heart center of Leipzig

Background

Cardiac sarcoidosis (CS) is frequently unrecognized cause of non-ischemic cardiomyopathy associated ventricular tachycardia (VT), who eventually require VT ablations because of refractory VTs; however, the reported long-term outcomes after VT ablation are conflicting. Because of the low diagnostic yield of the endomyocardial biopsy (EMB), diagnosis of CS is often based on clinical and imaging criteria, which can lead to misdiagnosing.

Purpose and objectives

The purpose of this study was to identity whether patients with histologically-proven CS (EMB+) have different patient, procedural characteristics and outcomes after VT ablation as compared to those in whom the diagnosis was based on clinical criteria only (EMB-).

Methods

Between 2015-2021, 153 patients with suspected CS were evaluated according to a specified protocol including CMR, 18FDG-PET, EMB, bronchoscopy and EBUS biopsy, and serum markers. Those who fulfilled the latest criteria for CS of the Japanese Circulation Society (JCS) were divided into 2 groups: EMB (+) CS proven by myocardial biopsy, and EMB (-) CS fulfilling the clinical criteria for CS. The following endpoints were defined: 1) VT recurrence after ablation; and 2) the composite endpoint of death, heart transplantation or LVAD implantation.

Results

We identified 76 patients fulfilling the JCS criteria for CS (mean age 50 ± 10.6 years, 38% female, EMB (+) 35.5%). The leading symptoms were as follows: sustained VT in 23 (30%), high-grade AV block in 23 (30%), heart failure in 18 (24%), and other in 12 pts (16%). EMB (+) and the EMB (-) patients had similar clinical characteristics except for the imaging findings. EMB (+) patients exhibit LGE in CMR in 96% vs. 73% in EMB (-); P=0.024, whereas 18FDG-PET showed abnormal myocardial activity in 91% in the EMB (+) vs. 65% in the EMB (-); P=0.028. The primary composite endpoint was reached in 7.4% in EMB (+) group and in 12.2 % in EMB (-) group; P = 0.7. VT ablation was performed in 15 cases: 9 ablations (33%) in EMB (+) vs. 6 ablations (12%) in EMB (-); P=0.037. At the end of the procedure, all inducible VTs were successfully ablated in 100% of the EMB (-) patients vs. 56% in EMB (+) patients; P=0.1. VT recurrence was 78% in EMB (+) group vs. 67% in EMB (-); P = 0.6. The only procedural difference between the groups was the presence of vast RV low-voltage areas in 67% of the EMB (+) vs. 0% in EMB (-); P = 0.028.

Conclusions

Patients with CS and positive EMB exhibit more often LGE in CMR, abnormal 18FDG-PET activity and required more frequently VT ablation. The procedural characteristics between both groups were similar, except for the frequently observed RV low-voltage areas in most EMB (+) patients, whereas the RV was not affected in any of the EMB (-) patients. In spite of these differences, the VT recurrence rates and the survival seemed not to be affected by the histological evidence of CS in EMB.

Supraglottic carcinoma with skeletal muscle and multiple bone secondaries

Soft tissue and bone secondaries in supraglottic carcinoma are extremely rare. A 55 year old male presented with history of hoarseness of voice, lump in left side of neck and pain in right shoulder region. Patient underwent Radiotherapy to primary as well as metastatic sites. After 10 months of follow-up, patient presented with distant metastasis to left shoulder, lumbar vertebra and sacrum. This case is being reported on account of its rarity.

Migrating rivers, consequent paleochannels: The unlikely partners and hotspots of flooding

Furious floods have become an omnipresent reality with the dawn of climate change and its transition to adulthood. Since climate change has now become an accepted reality, analysing the factors that favour or disfavour floods are an urgent requirement. Here we showcase the role of paleochannels, a product of migrating rivers, in a catastrophic flood in the south-western part of the Indian Peninsula. This study exposes whether these geomorphic features facilitate or impede floods. For the purpose of extracting paleochannels and floodwater mapping, we utilized multiple satellite datasets and took advantage of diversified feature selection algorithms. Paleochannels were demarcated viz., initial identification of a few paleochannels from literature and confirmation through high-resolution Google Earth (GE) images, followed by Principal Component Analysis (PCA) of Sentinel-2 images using Google Earth Engine (GEE), and a supervised classification of the principal bands 1, 2, and 3. False-positives were eliminated using Object-Oriented Analysis (OOA), which reduced the 964,254 polygons to 23,254. These polygons were visually affirmed using GE images that resulted in 115 paleochannels as the final collection. A few locations were verified through Vertical Electrical Sounding (VES) using the Schlumberger method. The features were analysed with the floodwaters of the 2018 catastrophic flood, extracted from Synthetic Aperture Radar (SAR) data, which was delineated for different temporal limits including the day of peak flood of August 17, 2018. During the peak flood, the inundation of the study area extended to 534.86 km2 with all the paleochannels getting immersed in floodwater. After 44 days of peak flood, the post-flood analysis revealed that when the floodwater receded 50%, the paleochannels emptied 87.39%, with the midland paleochannels discharging more than those of lowlands. Thus, such geomorphic features can be flood hotspots, but can be considered for discharging floodwater to mitigate flood risk in case of unprecedented rain.

Feasibility and Reliability of Smartwatch to Obtain Precordial Lead Electrocardiogram Recordings

The Apple Watch is capable of recording single-lead electrocardiograms (ECGs). To incorporate such devices in routine medical care, the reliability of such devices to obtain precordial leads needs to be validated. The purpose of this study was to assess the feasibility and reliability of a smartwatch (SW) to obtain precordial leads compared to standard ECGs. We included 100 participants (62 male, aged 62.8 ± 13.1 years) with sinus rhythm and recorded a standard 12-lead ECG and the precordial leads with the Apple Watch. The ECGs were quantitively compared. A total of 98 patients were able to record precordial leads without assistance. A strong correlation was observed between the amplitude of the standard and SW-ECGs’ waves, in terms of P waves, QRS-complexes, and T waves (all p-values < 0.01). A significant correlation was observed between the two methods regarding the duration of the ECG waves (all p-values < 0.01). Assessment of polarity showed a significant and a strong concordance between the ECGs’ waves in all six leads (91–100%, all p-values < 0.001). In conclusion, 98% of patients were able to record precordial leads using a SW without assistance. The SW is feasible and reliable for obtaining valid precordial-lead ECG recordings as a validated alternative to a standard ECG.

Starch bio-based composite active edible film functionalized with Carum carvi L. essential oil: antimicrobial, rheological, physic-mechanical and optical attributes

In the present study, the antimicrobial, rheological, mechanical, barrier and optical properties of Carrageenan and Manihot esculenta (composite) starch biobased edible film incorporated with caraway (Carum carvi L.) essential oil (EO) were investigated. The Minimum Inhibitory Concentration (MIC) of caraway oil against B. cereus, E. coli, P. aeruginosa and S. aureus were found to be 0.6, 1.4, 1.4 and 0.8% respectively. The Gas Chromatography- Mass Spectroscopy (GC-MS) of caraway EO expressed a distinct chromatogram peak for phenolic compounds. Rheological results of Film-Forming Solution (FFS) revealed solid-like viscoelastic behavior. Incorporation of caraway EO in the film caused significant (P < 0.05) increase in moisture, moisture absorption, bio-degradability in terms of film solubility, L value, total color difference (ΔE), haziness and transparency value, however, significantly (P < 0.05) decreased tensile strength and whiteness index were observed. The zone of inhibition of caraway EO incorporated films against all test bacteria were highly significant (P < 0.01) than control whereas antibacterial activity was found more towards gram-positive bacteria than gram-negative bacteria. No significant (P>0.05) changes in thickness, density, water activity, swelling, elongation at break, water vapor transmission rate, a and b value were observed with increasing caraway EO concentration. These results with some good rheological, physic-mechanical, antimicrobial and optical characteristics suggest the application of such active film into a variety of foods with improved food safety and quality.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13197-021-05028-1.

Epicardial ablation of ventricular tachycardia in patients with structural heart disease: a single-centre experience over 12 years

AIMS

Epicardial ablation has risen to an essential part of the treatment of ventricular tachycardias (VTs). In this study, we report the efficacy, risks, and current trends of epicardial ablation in structural heart disease as reported in a tertiary single centre over a 12-year period.

METHODS AND RESULTS

Two hundred and thirty-six patients referred for VT ablation underwent a successful epicardial access and were included in the analysis (89% non-ischaemic cardiomyopathy, 90% males, mean age 60 years, mean left ventricular ejection fraction 38.4%). After performing epicardial ablation the clinical VTs were eliminated in 87% of the patients and 71% of the cohort achieved freedom from VT during 22-month follow-up. Twelve patients (5%) suffered major procedure-related complications. Until the end of follow-up 47 (20%) patients died, 9 (4%) underwent a left ventricular assist device implantation and 10 (4%) patients received a heart transplantation. Antiarrhythmic drugs at baseline and during follow-up were independent predictors of VT recurrence. Atrial fibrillation, renal dysfunction, worse New York Heart Association class, and antiarrhythmic drugs at follow-up were associated with worse survival in our cohort.

CONCLUSION

In this large tertiary single-centre experience, percutaneous epicardial access was feasible in the large majority of the cohort with acceptably low complications rates. A combined endo-/epicardial approach resulted in 87% acute and 71% long-term success. Further studies are needed to clarify the role of routine combined endo-/epicardial ablation in these complex cardiomyopathies.

Inactivation of the superoxide dismutase by malondialdehyde in the nonalcoholic fatty liver disease: a combined molecular docking approach to clinical studies

The objective of the present study was to investigate the plasma levels of oxidative stress markers and the activity of antioxidant enzymes in NAFLD and healthy subjects. Furthermore, the interaction behaviors of malondialdehyde (MDA) with Cu/Zn superoxide dismutase (SOD1) enzyme were elucidated by molecular docking. The study involved 60 patients with NAFLD and 25 healthy volunteers. The plasma levels of oxidative stress parameters and antioxidant enzymes activity were determined. NAFLD patients had significantly higher alanine aminotransferase, MDA and nitric oxide metabolites values, as well as significantly lower total thiol and SOD activity than the control group. Based on the molecular docking, MDA could deactivate the enzymatic activity of SOD1. Impaired antioxidant defense systems may be involved in the progression of NAFLD. This study provides direct evidence at a molecular level to explain that MDA may exert its oxidant activity by specific action within the specific molecular pathway.HighlightsImpairing antioxidant defense systems may be a main factor in the progression of nonalcoholic fatty liver disease (NAFLD).Increasing MDA and NO metabolites, as well as decreasing TSH values and SOD activity in NAFLD patients as compared to control subjectsIncreasing MDA level in NAFLD patients may be inactivate SOD activity by reaction with the key residues Cu ion inside active site of the enzyme catalytic site.

LV Pseudoaneurysm With Concomitant Mitral Valve Defect After LV Summit Ablation: A Rare Late Complication

A 25-year-old male patient with highly symptomatic, monomorphic, premature ventricular contractions presented for repeat ablation after failed endocardial ablation. Three weeks after excessive endocardial and epicardial ablation on the left ventricular summit, the patient was admitted again with tamponade following a pseudoaneurysm on the ablation site. (Level of Difficulty: Advanced.).

Atrial fibrillation: is there a role for cardiac troponin?

Atrial fibrillation (AF) is the most common sustained arrhythmia, and its prevalence rate is expected to be doubled over the next decades. Despite the wide use of biomarkers in the management of different cardiac diseases such as myocardial infarction and heart failure, utilization of biomarkers in AF management is not routinely recommended by current guidelines. There is also growing evidence that higher levels of cardiac-specific troponin, as an intracellular protein involved in cardiomyocyte contraction, may be associated with the risk of incident and recurrent AF and its complications. In the present paper, we review the association between troponin and AF and propose clinical suggestions for use of troponin in the management of AF patients.

Gender differences in patients with structural heart disease undergoing VT ablation

INTRODUCTION

This study sought to examine gender differences in patients with structural heart disease (SHD) referred for ablation of ventricular tachycardia (VT).

BACKGROUND

Female patients are often underrepresented in large studies. Significant differences in the clinical presentation, treatment, and prognosis of female patients have been described in previous studies.

METHODS AND RESULTS

We investigated 88 female patients with SHD undergoing VT ablation (mean age 59 years, 56% nonischemic cardiomyopathy, mean left ventricular ejection fraction 35%, 82% in electrical storm). A case-control study with 88 male patients was performed and the results regarding clinical and procedural characteristics, acute and long-term results of the two groups were compared. The female patients had more arrhythmogenic substrate, as they more commonly presented with electrical storm (p = .016) and had a higher number of inducible VT morphologies during the procedure (p = .018). Moreover, the female patients were less likely to have an optimized heart failure medical treatment at baseline (p = .030) and required more time from the first manifestation of the VT to ablation referral (p = .034). Although fewer epicardial ablations were performed in female patients (p = .019), the two groups showed similar results regarding VT noninducibility as ablation endpoint (p = .844), major procedure-related complications (p = .719) and freedom from VT during follow-up (p = .268). Moreover, the overall mortality in the two groups was similar (p = .176). Advanced NYHA class was associated with worse transplant and assist-device-free survival in the female group.

CONCLUSION

Female patients presenting for VT ablation had more arrhythmogenic substrate and were less likely to have an optimized heart failure medical treatment. Nevertheless, the procedural acute and long-term outcomes between the two genders were similar.

Role of assist device implantation and heart transplantation in the long-term outcome of patients with structural heart disease after catheter ablation of ventricular tachycardia

Introduction

Ablation of ventricular tachycardias (VTs) in patients with structural heart disease (SHD) has been associated with advanced heart failure and poor survival.

Methods and results

This matched case-control study sought to assess the difference in survival after left ventricular assist device (LVAD) implantation and/or heart transplantation (HTX) in SHD patients undergoing VT ablation. From the initial cohort of 309 SHD patients undergoing VT ablation (187 ischemic cardiomyopathy, mean age 64 ± 12 years, ejection fraction of 34 ± 13%), 15 patients received an LVAD and nine patients HTX after VT ablation during a follow-up period of 44 ± 33 months.

Long-term survival after LVAD did not differ from the matched control group (p = 0.761), although the cause of lethal events was different. All post-HTX patients survived during follow-up.

Conclusion

In this matched case-control study on patients with SHD undergoing VT ablation, patients that received LVAD implantation had similar survival compared to the control group after 4‑year follow-up, while the patients with HTX had a significantly better outcome.

Observations during the COVID-19 pandemic in chronic heart failure patients with complex devices in a tertiary care cardiac centre using the HeartLogic software

Funding Acknowledgements

Type of funding sources: None.

Introduction

Decompensation of heart failure leading (HF) to hospitalisation is the single most important drain on healthcare resources when managing patients with left ventricular systolic dysfunction. Cardiac resynchronisation therapy with/without defibrillators (CRT-P/D) decreases hospitalisation due to HF and improves survival while implantable cardiac defibrillators (ICD"s) have a favourable effect on the former. Proprietary software algorithms embedded in these complex devices give an early warning to clinicians when decompensation of HF is imminent allowing preventative action to be undertaken.

HeartLogic (HL) is one such new algorithm in Boston Scientific CRT-D/ICD devices using multiple sensors to track 5 physiological parameters, combining them into one composite Index, with an Alert being triggered if the Index is >16. The COVID-19 pandemic, due to multiple reasons, resulted in a significant decrease in availability of routine HF services in the United Kingdom, especially during the initial lockdown period from 23rd March to 1st July 2020.

Aim

To assess the impact of the COVID-19 pandemic, using HL, in patients with HF and complex devices. 

Materials and Methods

Retrospective analysis of patients in a tertiary care cardiac centre in whom the HL software had been activated in March/April 2019 (n = 49) and comparison of those with (Group A n = 21) and without (Group B n = 28) an Alert (HLA) during the COVID-19 pandemic. 

Results (Table): Whole cohort n = 49. Age:  72 ± 12 years, Median: 75, Range: 36-95. 36/49 (73.5%) males. Type of device implanted: Resonate X4 CRT-D: 28/49 (57.1%); Momentum CRT-D: 8/49 (16.3%); Resonate ICD: 13/49 (26.5%). Ischaemic aetiology of HF: 35/49 (71.4%), Total duration of HL monitoring: 632 ± 7 days (median: 632; range: 626-672).  There was no difference in the age, gender, and type of device implanted between Group A and Group B. Over nearly ∼1 year of monitoring in each of the groups, Group A had more unstable HF with 10/21 (47.6%) having their first HLA during the pandemic. Multiple HLA"s, longer period in HLA and those with ischaemic aetiology of HF were higher in Group A. 17/40 (42.5%) HLA"s in Group A were within the first lockdown period (March - July). 24/28 (85.7%) patients in Group B had no HLA"s either before or during the pandemic. There was no difference in the HLA score between Groups A and B.

Conclusion

In this limited group of patients with a medium term follow-up, using the HeartLogic software, patients with ischaemic aetiology of HF and those with more HLA"s prior to the pandemic did worse than those who no HLA"s. First HLA"s, multiple alerts and longer duration of alerts in this group of patients suggests a lack of access to adequate HF services during the pandemic. It has implications with regard to how HF services are configured in future whenever resources are constrained.

Chemical ordering as a precursor to formation of orderedδ-UZr2phase: a theoretical and experimental study

A combination of special quasi-random structure (SQS) analysis, density functional theory (DFT) based simulations and experimental techniques are employed in determining the transformation pathway for the disorderedγ-(U, Zr) phase (bcc structure) to transform into the chemically orderedδ-UZr₂phase (C32, AlB₂type structure). A novel Monte-Carlo based strategy is developed to generate SQS structures to study theβ→ωdisplacive phase transformation in A_1-xB_xbinary random alloy. Structures generated with this strategy and using DFT calculations, it is determined that (222)_bccplane collapse mechanism is energetically unfavorable in chemically disordered environment at UZr₂composition. A mechanically and dynamically stable 24 atom SQS structure is derived which serves as a structural model of chemically orderedδ-UZr₂structure. Finally, a thermodynamic basis for the mechanism of theγtoδtransformation has been established which ensures chemical ordering is a precursor to the subsequent displacive transformation to form chemically orderedδ-UZr₂structure.

Association of low-voltage areas with the regional wall deformation and the left atrial shape in patients with atrial fibrillation: A proof of concept study

Background

Left atrium (LA) remodeling is associated with atrial fibrillation (AF) and reduced success after AF ablation, but its relation with low-voltage areas (LVA) is not known. This study aimed to evaluate the relation between regional LA changes and LVAs in AF patients.

Methods

Pre-interventional CT data of patients (n = 24) with LA-LVA (<0.5 mV) in voltage mapping after AF ablation were analyzed (Surgery Explorer, QuantMD LLC). To quantify asymmetry (ASI = LA-A/LAV) a cutting plane parallel to the rear wall and along the pulmonary veins divided the LA-volume (LAV) into anterior (LA-A) and posterior parts. To quantify sphericity (LAS = 1-R/S), a patient-specific best-fit LA sphere was created. The average radius (R) and the mean deviation (S) from this sphere were calculated. The average local deviation (D) was measured for the roof, posterior, septum, inferior septum, inferior-posterior and lateral walls.

Results

The roof, posterior and septal regions had negative local deviations. There was a correlation between roof and septum (r = 0.42, p = 0.04), lateral and inferior-posterior (r = 0.48, p = 0.02) as well as posterior and inferior-septal deviations (r = −0.41, p = 0.046). ASI correlated with septum deformation (r = −0.43, p = 0.04). LAS correlated with dilatation (LAV, r = 0.49, p = 0.02), roof (r = 0.52, p = 0.009) and posterior deformation (r = −0.56, p = 0.005). Extended LVA correlated with local deformation of all LA walls, except the roof and the septum. LVA association with LAV, ASI and LAS did not reach statistical significance.

Conclusion

Extended LVA correlates with local wall deformations better than other remodeling surrogates. Therefore, their calculation could help predict LVA presence and deserve further evaluation in clinical studies.

Plasma Levels and Gene Expression of RANK in Non-Alcoholic Fatty Liver Disease

BACKGROUND

The pathobiology of initiation and progression of nonalcoholic fatty liver disease (NAFLD) has not been completely elucidated. It seems that the RANK/RANKL/OPG cytokine system play an etiologic role in pathogenesis of this disease. This study aimed to investigate the plasma content and gene expression of RANK in NAFLD patients as compared to healthy individuals.

METHODS

This case-control work was performed on 63 patients with NAFLD and 25 healthy subjects. The plasma levels of RANK and biochemical parameters were measured using ELISA and colorimetric methods, respectively. Also, RANK mRNA content was evaluated by quantitative RT-PCR in peripheral blood mononuclear cells.

RESULTS

RANK plasma contents were shown to be lower in NAFLD patients than in control subjects (1.02 ± 0.75 and 1.41 ± 1 ng/mL, respectively (p = 0.008)). The differences in gene expression of RANK between NAFLD patients and controls were significant (p = 0.001). In the NAFLD patients, RANK was inversely correlated with HDL. Logistic regression showed the association of RANK plasma content with the risk of NAFLD. Moreover, ROC curve analysis showed that RANK has a great ability to differentiate between NAFLD patients and controls.

CONCLUSIONS

This study for the first time showed lower plasma and mRNA levels of RANK in NAFLD patients compared to control individuals. These results recommend a possible association between RANK and pathobiology of NAFLD.

VT ablation in geriatric patients with structural heart disease: Should there still be an age limit?

INTRODUCTION

This study sought to examine the feasibility and outcome of ablation of ventricular tachycardias (VTs) in a contemporary cohort of geriatric patients with structural heart disease (SHD).

BACKGROUND

Geriatric patients are often underrepresented in large studies. As frailty is becoming an increasing problem, we need to examine the best course of action for this population.

METHODS AND RESULTS

We investigated 68 SHD-patients ≥ 75 years old undergoing VT-ablation (men 88%, ischemic cardiomyopathy 77%, electrical storm 72%, mean left ventricular ejection fraction 31%) and divided the cohort into two groups: 75-79 years old (n = 51) and ≥80 years old (n = 17). The two groups showed similar results regarding noninducibility as ablation endpoint (p = .693), major procedure-related complications (p = .488), and VT-recurrence (p = .882) during the 39-month follow-up. At the end of the follow-up, 10 patients in the octogenarian group (59%) versus 16 patients of the other group (31%) died.

CONCLUSION

Geriatric patients with SHD including octogenarians showed similar results regarding procedural endpoints, freedom of VT, and major procedure-associated complications after VT-ablation. When ablation is indicated, age alone should not be an inhibiting factor to treat these patients.

Validation of the VT-LVAD score for prediction of late VAs in LVAD recipients

OBJECTIVES

This study sought to validate the performance of the VT-LVAD risk model in predicting late ventricular arrhythmias (VAs) in patients after left ventricular assist device (LVAD) implantation.

BACKGROUND

The need for implantable cardioverter-defibrillator (ICD)-implantation in LVAD recipients is not well studied. A better selection of the patients with high risk for late VAs could lead to a more targeted ICD-implantation or replacement.

METHODS

The study evaluated the performance of the VT-LVAD prognostic score (VAs prior LVAD, no ACE-inhibitor in medication, heart failure duration > 12 months, early VAs post-LVAD implantation, atrial fibrillation prior LVAD, idiopathic dilated cardiomyopathy) for the endpoint of the occurrence of late VAs in 357 LVAD patients in Heart Centre of Leipzig.

RESULTS

From the initial 460 patients, 357 (age: 58 ± 10 years; left ventricular ejection fraction: 20 ± 6%; HeartWare: 50%; HeartMate III: 42%) were assigned to four risk groups according to their VT-LVAD score varying from low risk to very high risk. After 25 months, late VAs occurred in 130 patients. The VT-LVAD score was an independent predictor of late VAs (multivariate analysis; p = < .001; goodness-of-tip p = .347; odds ratio: 4.8). While there was no statistically significant difference between the low- and intermediate-risk group, risk stratification for patients with high risk and very high risk performed more accurately (pairwise comparison p = .005 and p < .001, respectively).

CONCLUSIONS

The VT-LVAD score predicted accurately the occurrence of late VAs in high-risk LVAD recipients in a large external cohort of LVAD recipients supporting its utility for more targeted ICD implantations.

Predictors of rhythm outcomes after cardiac resynchronization therapy in atrial fibrillation patients: When should we use an atrial lead?

BACKGROUND

Cardiac resynchronization therapy (CRT) is widely used in atrial fibrillation (AF) patients and could impact rhythm stability.

HYPOTHESIS

We aimed to identify predictors of sinus rhythm (SR) stability or AF progression in a real-word cohort of CRT-AF patients.

METHODS

From 330 consecutive implantable cardioverter-defibrillator implantations due to ischemic or dilated cardiomyopathy, 65 (20%) patients with AF history (paroxysmal, n = 32) underwent a CRT implantation with an atrial electrode and were regularly followed every 4-6 months. Rhythm restoration was attempted for most AF patients based on symptoms, biventricular pacing (BP), and lack of thrombi.

RESULTS

After 33 months, 18 (28%) patients progressed to permanent mode switch (MS≥99%) and 20 (31%) patients had stable SR (MS < 1%). Logistic regression showed that history of persistent AF (OR: 8.01, 95%CI: 2.0-31.7, p = .003) is associated with higher risk of permanent MS. In persistent AF patients, a bigger left atrium (OR: 1.2 per mm, 95%CI: 1.03-1.4, p = .025) and older age (OR: 1.15 per life-year, 95%CI: 1.01-1.3, p = .032) were predictors of future permanent MS. Paroxysmal AF at implantation (OR: 5.96, 95%CI: 1.6-21.9, p = .007) and increased BP (OR: 1.4 per 1%, 95%CI: 1.05-1.89, p = .02) were associated with stable SR. In persistent AF patients, stable SR correlated with higher BP (98 ± 2 vs. 92 ± 8%, p < .001).

CONCLUSION

In patients with AF undergoing CRT implantation, persistent AF, LA dilatation and advanced age relate to future permanent MS (AF), whereas high BP promotes SR stability. These findings could facilitate the management of CRT-AF patients and guide therapy in order to maximize its effect on rhythm.

Very late arrhythmia recurrences in patients with sinus rhythm within the first year after catheter ablation: The Leipzig Heart Center AF Ablation Registry

AIMS 

Arrhythmia recurrences after catheter ablation of atrial fibrillation (AF) still remain an important management issue. Recently, the APPLE score had been introduced to predict rhythm outcomes within 12 months after catheter ablation, while the simple MB-LATER score was developed for the prediction of very late recurrence of AF (VLRAF) occurring after 12 months. The aim of this study was to compare APPLE and MB-LATER scores in predicting VLRAF.

METHODS AND RESULTS 

The study population included arrhythmia-free patients within first 12 months after first radiofrequency catheter ablation from The Heart Center Leipzig AF Ablation Registry. The APPLE [one point for Age >65 years, Persistent AF, imPaired eGFR <60 mL/min/1.73 m2, Left atrial (LA) diameter ≥43 mm, EF <50%] and MB-LATER scores [one point for Male gender, Bundle branch block or QRS >120 ms, LA diameter ≥47 mm, AF Type (persistent AF), Early Recurrence <3 months] were calculated before and 3 months after ablation, respectively. We followed 482 patients {age 61 [interquartile range (IQR) 54-68] years, 66% males, 32% persistent AF} for median 40 (IQR 35-50) months. There were 184 patients (38.3%) with arrhythmia recurrences within 13-60 months after ablation. On multivariate analysis, APPLE [odds ratio (OR) 1.517, 95% confidence interval (CI) 1.244-1.850, P < 0.001] and MB-LATER (OR 1.437, 95% CI 1.211-1.705, P < 0.001) scores and diabetes mellitus (OR 2.214, 95% CI 1.353-3.625, P = 0.002) were significantly associated with arrhythmia recurrences. Receiver operating characteristic curve analyses demonstrated moderate prediction for both scores [area under the curve (AUC) 0.607, P < 0.001 for APPLE score, AUC 0.604, P < 0.001 for MB-LATER].

CONCLUSION 

Prediction of VLRAF is similar for both APPLE and MB-LATER scores. A better score remains still a clinical unmet need.

Left atrial activation and asymmetric anatomical remodeling in patients with atrial fibrillation: The relation between anatomy and function

BACKGROUND

Identifying patients with advanced left atrial (LA) remodeling before catheter ablation (CA) of atrial fibrillation (AF) is crucial.

HYPOTHESIS

This study aimed to identify echocardiographic parameters associated with changes in anatomy and conduction properties of the left atrium (LA).

METHODS

We examined 75 AF patients prior to CA and measured the intervals from the P-wave-onset to four mitral annulus sites by pulsed-wave tissue Doppler imaging (PW-TDI). Patients were grouped to an upward U-pattern (delayed anterior activation) and a downward D-pattern (earliest LA activation anterior). CT-data were used to measure the LA volume (LAV). LAV was divided into anterior- (LA-A) and posterior-parts by a plane, parallel to the posterior wall and between the veins and the appendage, to calculate the asymmetry index (ASI = LA-A/LAV).

RESULTS

Patients with U-pattern (n = 66) had a higher ASI (65 ± 6 vs. 61 ± 3%, p = .014), older age (61 ± 11 vs. 51 ± 11 years, p = .03) and more diastolic dysfunction (71 vs. 22%, p = .008) Multivariate regression showed that age (OR 1.1 per year, CI 1.007-1.199) and diastolic dysfunction (OR 6.36, CI 1.132-35.7, p = .036) were independent predictors of the U-pattern. Diastolic dysfunction (B 4.49, CI 1.61-7.37, p = .003) was the only independent predictor of ASI in linear regression analysis.

CONCLUSION

AF patients with a U-pattern have an increased LA asymmetry. Diastolic dysfunction is a common cause of this LA activation and remodeling. Therefore, detection of a U-pattern signifies patients with advanced AF and may facilitate selection for an appropriate ablation strategy.

Circulating mRNA and plasma levels of osteoprotegerin and receptor activator of NF-κB ligand in nonalcoholic fatty liver disease

Pathogenesis of the beginning and progression of nonalcoholic fatty liver disease (NAFLD) has not been clarified exactly. The osteoprotegerin (OPG)/receptor activator of NF-κB ligand (RANKL) axis seems to play an imperative function in the onset and progression of this disease. The goal of the present study was to investigate the peripheral blood mononuclear cell (PBMC) expression and plasma levels of RANKL and OPG cytokines in NAFLD patients and compare them with healthy group. Plasma levels of OPG and RANKL were determined with ELISA kits in 57 men with NAFLD and 25 healthy men as controls. Biochemical and anthropometric parameters tests were also evaluated in the study groups. RANKL and OPG mRNA contents were evaluated by quantitative RT-PCR. OPG contents were markedly decreased in NAFLD patients as compared with healthy patients [1.43 (1.05-5.45)] versus [2.94 (1.76-4.73)] ng/mL; P = 0.007). The levels of RANKL were significantly reduced in NAFLD patients [74.00 (56.26-203.52) ng/mL] than in healthy patients [119.37 (83.71-150.13) ng/mL]; (P = 0.03). Also, OPG and RANKL gene expression were significantly decreased in NAFLD patients in comparison with the control group (P < 0.05). Moreover, receiver operating characteristic curve indicated that OPG may have a good capability to discriminate between NAFLD patients and normal individuals. A positive correlation was observed between OPG and RANKL in plasma sample (r = 0.495) (P = 0.000). Decreased plasma levels and gene expression of RANKL and OPG cytokines in NAFLD patients indicate that there is a relationship between these cytokines and the pathology of NAFLD disease. Confirmation of this association as well as the mechanism and role of these cytokines in NAFLD require further studies.

Feasibility and Reliability of SmartWatch to Obtain 3-Lead Electrocardiogram Recordings

Some of the recently released smartwatch products feature a single-lead electrocardiogram (ECG) recording capability. The reliability of obtaining 3-lead ECG with smartwatches is yet to be confirmed in a large study. This study aimed to assess the feasibility and reliability of smartwatch to obtain 3-lead ECG recordings, the classical Einthoven ECG leads I-III compared to standard ECG. To record lead I, the watch was worn on the left wrist and the right index finger was placed on the digital crown for 30 s. For lead II, the watch was placed on the lower abdomen and the right index finger was placed on the digital crown for 30 s. For lead III, the same process was repeated with the left index finger. Spearman correlation and Bland-Altman tests were used for data analysis. A total of 300 smartwatch ECG tracings were successfully obtained. ECG waves' characteristics of all three leads obtained from the smartwatch had a similar duration, amplitude, and polarity compared to standard ECG. The results of this study suggested that the examined smartwatch (Apple Watch Series 4) could obtain 3-lead ECG tracings, including Einthoven leads I, II, and III by placing the smartwatch on the described positions.

Complex cases of acquired pulmonary vein stenosis after radiofrequency ablation: is surgical repair an option?

Aims

Results of catheter based interventional treatment for pulmonary vein stenosis (PVS) following radiofrequency ablation (RFA) for atrial fibrillation remain suboptimal. Surgical repair may represent an alternative therapy, though long-term results have not been thoroughly investigated.

Methods and results

We retrospectively assessed all patients in our centre undergoing surgical repair for radiofrequency-induced PVS. Data regarding surgical technique, clinical outcome, and rate of pulmonary vein (PV) restenosis were collected and analysed. Between 2004 and 2016, the rate for PVS resulting from RFA for atrial fibrillation in our institution was 0.79% (76/9633). During this period, five male patients with multiple PVS (3 ± 1) underwent surgical repair of a total of 13 symptomatic PVS. Surgery was performed in a standard setting under cardiopulmonary bypass. Stenotic veins were incised longitudinally followed by a patch augmentation plasty using either bovine pericard (n = 7) or polytetrafluoroethylene (PTFE) patches (n = 5). Localization of incision was on the anterior side of the PV only (n = 8) or on both the anterior and posterior sides (n = 4). In one PVS lesion, mechanical dilatation was sufficient. Long-term follow-up after 60 ± 69 months revealed an average restenosis rate of 38%. Restenosis was defined as narrowing >70%. All patients reported clinical improvement of symptoms at follow-up.

Conclusion

Even in the era of wide circumferential lesions, PVS still occurs. While surgical PV patch plasty represents a valuable treatment option, restenosis remains an issue during follow-up. Nevertheless, surgical repair achieves highly acceptable long-term results for RFA-acquired PVS. Hence, it should be routinely discussed as a therapeutic option in cases with multiple PVS.

Predictors of long-term mortality after catheter ablation of ventricular tachycardia in a contemporary cohort of patients with structural heart disease

Aims

Ablation of ventricular tachycardias (VTs) in patients with structural heart disease has been established in the past decades as an effective and safe treatment. However, the prognosis and long-term outcome remains poor.

Methods and results

We investigated 309 patients with ischaemic cardiomyopathy (ICM) and non-ischaemic cardiomyopathy (NICM) (186 ICM, 123 NICM; 271 males; mean age 64.1 ± 12 years; ejection fraction 34 ± 13%) after ≥1 VT ablations over a mean follow-up period of 34 ± 28 months. Electrical storm was the indication for 224 patients (73%), whereas 86 patients (28%) underwent epicardial as well as endocardial ablation. During follow-up, 132 patients (43%) experienced VT recurrence and 97 (31%) died. Ischaemic cardiomyopathy and NICM patients showed comparable results, regarding procedural endpoints, complications, VT recurrence and survival. The Cox-regression analysis for all-cause mortality revealed that the presence of higher left ventricular end-diastolic volume (LVEDV; P &lt; 0.001), male gender (P = 0.018), atrial fibrillation (AF; P &lt; 0.001), chronic obstructive pulmonary disease (COPD; P = 0.001), antiarrhythmic drugs during the follow-up (P &lt; 0.001), polymorphic VTs (P = 0.028), and periprocedural complications (P = 0.001) were independent predictors of mortality.

Conclusion

Ischaemic cardiomyopathy and NICM patients undergoing VT ablation had comparable results regarding procedural endpoints, complications, VT recurrence and 3-year mortality. Higher LVEDV, male gender, COPD, AF, polymorphic VTs, use of antiarrhythmics, and periprocedural complications are strong and independent predictors for increased mortality. The PAINESD score accurately predicted the long-term outcome in our cohort.

Oesophageal Probe Evaluation in Radiofrequency Ablation of Atrial Fibrillation (OPERA): results from a prospective randomized trial

Aims

The aim of the study was to determine the incidence of oesophageal lesions after radiofrequency ablation (RFA) of atrial fibrillation (AF) with or without the use of oesophageal temperature probes.

Methods and results

Two hundred patients were prospectively randomized into two groups: the OPERA+ group underwent RFA using oesophageal probes (SensiTherm™); the OPERA− group received RFA using fixed energy levels of 25 W at the posterior wall without an oesophageal probe. All patients underwent post-interventional endoscopy and Holter-electrocardiogram after 6 months. (Clinical.Trials.gov: NCT03246594). One hundred patients were randomized in OPERA+ and 100 patients in OPERA−. The drop-out rate was 10%. In total, 18/180 (10%) patients developed endoscopically diagnosed oesophageal lesions (EDEL). There was no difference between the groups with 10/90 (11%) EDEL in OPERA+ vs. 8/90 (9%) in OPERA− (P = 0.62). Despite the higher power delivered at the posterior wall in OPERA+ [28 ± 4 vs. 25 ± 2 W (P = 0.001)], the average EDEL size was equal [5.7 ± 2.6 vs. 4.5 ± 1.7 mm (P = 0.38)]. The peak temperature did not correlate with EDEL size. During follow-up, no patient died. Only one patient in OPERA− required a specific therapy for treatment of the lesion. Cumulative AF recurrence after 6 (3–13) months was 28/87 (32%) vs. 34/88 (39%), P = 0.541.

Conclusion

This first randomized study demonstrates that intraoesophageal temperature monitoring using the SensiTherm™ probe does not affect the probability of developing EDEL. The peak temperature measured by the thermoprobe seems not to correlate with the incidence of EDEL. Empiric energy reduction at the posterior wall did not affect the efficacy of the procedure.

Direct hybridization gap from intersite and onsite electronic interactions in CeAg2Ge2

Electronic and crystal structure studies are presented to describe the role of intersite and onsite interactions for antiferromagnetic ordering in CeAg2Ge2. The crystal structure showed a prominent magnetovolume effect with anomalous negative thermal expansion at low temperature as a consequence of itinerant electron magnetism. The direct hybridization gap with a V-shaped band observed in the angle resolved photoemission data at room temperature, indicates that spin polarized quasiparticle states exist in the gapped region. Valence band broadening and enhanced localization effects at low temperature indicate strong hybridization of the valence orbitals of Ce atoms with the near neighbor Ge atoms. We find that the intersite interaction between the Ce atoms at high temperature stabilizes the onsite interaction at low temperature that leads to the spin density wave type antiferromagnetism in CeAg2Ge2.

Clinical utility of cardiovascular magnetic resonance imaging in patients with implantable cardioverter defibrillators presenting with electrical instability or worsening heart failure symptoms

BACKGROUND

Data on the usefulness of cardiovascular magnetic resonance (CMR) imaging for clinical decision making in patients with an implanted cardioverter defibrillator (ICD) are scarce. The present study determined the impact of CMR imaging on diagnostic stratification and treatment decisions in ICD patients presenting with electrical instability or progressive heart failure symptoms.

METHODS

212 consecutive ICD patients underwent 1.5 T CMR combining diagnostic imaging modules tailored to the individual clinical indication (ventricular function assessment, myocardial tissue characterization, adenosine stress-perfusion, 3D-contrast-enhanced angiography); four CMR examinations (4/212, 2%) were excluded due to non-diagnostic CMR image quality. The resultant change in diagnosis or clinical management was determined in the overall population and compared between ICD patients for primary (115/208, 55%) or secondary prevention (93/208, 45%). Referral indication consisted of documented ventricular tachycardia, inadequate device therapy or progressive heart failure symptoms.

RESULTS

Overall, CMR imaging data changed diagnosis in 40% (83/208) with a significant difference between primary versus secondary prevention ICD patients (37/115, 32% versus 46/93, 49%, respectively; p = 0.01). The information gain from CMR led to an overall change in treatment in 21% (43/208) with a similar distribution in primary versus secondary prevention ICD patients (25/115,22% versus 18/93,19%, p = 0.67). The effect on treatment change was highest in patients initially scheduled for ventricular tachycardia ablation procedure (18/141, 13%) with revision of the treatment plan to medical therapy or coronary revascularization.

CONCLUSIONS

CMR imaging in ICD patients presenting with electrical instability or worsening heart failure symptoms provided diagnostic or management-changing information in a considerable proportion (40% and 21%, respectively).

Circulating Levels of Pro-inflammatory Cytokines in Patients with Nonalcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis

BACKGROUND

Pro-inflammatory cytokines are associated with systemic inflammatory responses.

OBJECTIVE

To investigate the levels of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) in patients with non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH) compared to healthy individuals.

METHODS

This case-control study was conducted on 30 patients with NAFL, 30 patients with NASH, and 30 healthy volunteers. The plasma level of IL-1β, IL-6, and TNF-α were determined by ELISA, and biochemical parameters were measured using colorimetric methods.

RESULTS

IL-1β and IL-6 levels were significantly higher in patients with NASH compared with NAFL and control group. However, TNF-α levels had no significant variations in NAFL and NASH patients compared to the control group (p=0.903 and p=0.960, respectively).

CONCLUSION

Results showed that the levels of ALT activity and pro-inflammatory cytokines were higher in patients with NASH compared to control and NAFL subjects; Therefore, steatosis and inflammation develop as a result of excessive pro-inflammatory factors in NASH.

Structural, thermodynamic, electronic and elastic properties of Th1-xUxO2 and Th1-xPuxO2 mixed oxides

The structural, thermodynamic, electronic, and elastic properties of Th1-xUxO2 and Th1-xPuxO2 mixed oxides (MOX) have been calculated with Hubbard corrected density functional theory (DFT+U) to account for the strong 5f electron correlations. The ideal solid solution is approximated by special quasi-random structures and the U-ramping method is used to account for the presence of metastable states in the self-consistent field solution of the DFT+U approach. The mixing enthalpy (ΔHmix) is positive throughout the composition range of the Th1-xUxO2 MOX, consistent with a simple miscibility gap (at low temperature) phase diagram. The behavior of the Th1-xPuxO2 MOX is more complex, where ΔHmix is positive in the ThO2-rich region and negative in the PuO2-rich region. Electronic structure analysis shows that substitution of Th by U/Pu in ThO2 leads to a reduction of the average Th-O bond lengths, causing distortion in the crystal structure. The distortion in the crystal structure results in an increase in the conduction bandwidth and a reduction of the band-gap in the MOX. Good agreement of our DFT+U calculated elastic properties of ThO2, UO2 and PuO2 compounds with experiments leads to convincing prediction of these properties for Th1-xUxO2 and Th1-xPuxO2 MOX.

Dynamic changes in the signal-averaged electrocardiogram are associated with the long-term outcomes after ablation of ischemic ventricular tachycardia

PURPOSE

Signal-averaged ECG (SAECG) can detect inhomogeneous myocardial conduction in patients presenting with ventricular tachycardia (VT) after myocardial infarction. Radiofrequency ablation (RFCA) aims at elimination of the endocardial late potentials and non-inducibility of VT. Previously, we demonstrated that abnormal SAECG at baseline can return to normal after a successful VT ablation. The present research investigates the post-ablation changes in SAECG after RFCA of VT and their relation to the procedural long-term outcomes.

METHODS

Thirty-three patients (31 male; age 68 ± 9 years; EF 36 ± 12%) with ischemic VT were prospectively enrolled to receive RFCA. One VT (range 1-7) per patient was ablated using substrate-guided RFCA and complete success was achieved in 28 (85%) cases. SAECG was performed before (t1), immediately after (t2), and at least 6 months (t3) after the RFCA.

RESULTS

After RFCA, the amount of patients showing abnormal SAECG decreased from 82% initially (t1) to 57.6% post-interventionally (t2); P = 0.008; and remained unchanged thereafter in 57% (t3). Patients who experienced VT recurrence (VT+) during the follow-up period had broader averaged QRS (t2): (VT+) 150 ± 26 vs. (VT-) 129 ± 21 ms; P = 0.015, as well as longer LAS40 (t2): (VT+) 60 ± 26 vs. (VT-) 43 ± 18 ms; P = 0.03. Abnormal SAECG (t2) was a strong predictor for VT recurrence: HR 5.4; 95% CI 1.5-21. SAECG detected more late potentials in patients with inferior than in those with anterior scars: 95% vs. 58%; P = 0.016.

CONCLUSIONS

RFCA of VT in the left ventricle can improve an abnormal SAECG in some patients after myocardial infarction. Normal SAECG after RFCA of VT is associated with a lower risk for VT recurrence and death.

Materiality of Edible Film Packaging in Muscle Foods: A Worthwhile Conception

Muscle foods are extremely extensive food products that are relished throughout the world. They are known for their exclusive nutritional content and bio-availability however, at the same time, they also provide apposite media for the growth of pathogenic and spoilage microorganisms. Packaging seems to be a substantial approach to overcome this problem, but most of the packaging involves the usage of non-biodegradable and non-renewable material like plastic, nylon, polyester, etc. The alarming situation caused by synthetic material has been realized worldwide and several scientists, agencies, and the food industry are working globally to explore materials that are derived from the natural source. Biodegradable films are an excellent alternative to conventional plastics. These biodegradable films and coatings are derived from various biological sources and are receiving considerable importance in recent years. Different meat and meat product needs specific packaging condition and these active, composite bio-based films are having a wide potential in the meat sector. This review gathers the research and findings over the period of time-related to biodegradable edible film applied to muscle foods.