Ventricular insertion site ablation of a Mahaim atriofascicular fibre in Ebstein anomaly

Ebstein anomaly is frequently associated with accessory pathways, including Mahaim atriofascicular fibres. We herein illustrate successful Mahaim fibre ablation in Ebstein anomaly by targeting the ventricular insertion site below the tricuspid ridge.

Comparing pulsed field electroporation and radiofrequency ablation for the treatment of paroxysmal atrial fibrillation: design and rationale of the BEAT PAROX-AF randomized clinical trial

AIMS

Using thermal-based energy sources [radiofrequency (RF) energy/cryo energy] for catheter ablation is considered effective and safe when performing pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (AF). However, treatment success remains limited and complications can occur due to the propagation of thermal energy into non-target tissues. We aim to compare pulsed field ablation (PFA) with RF ablation in terms of efficacy and safety for patients with drug-resistant paroxysmal AF.

METHODS AND RESULTS

The BEAT PAROX-AF trial is a European multicentre, superiority, open-label randomized clinical trial in two parallel groups. A total of 292 participants were recruited in 9 high-volume European clinical centres in 5 countries. Patients with paroxysmal AF were randomized to PFA (FARAPULSE Endocardial Ablation System©, Boston Scientific) or RF using the CLOSE protocol with contact force sensing catheter (SmartTouch© catheter and CARTO© Biosense Webster). The primary endpoint will be the 1-year recurrence of atrial arrhythmia, and the major secondary safety endpoint will be the occurrence of acute (<7 days) procedure-related serious adverse events, or pulmonary vein stenosis, or atrio-oesophageal fistula up to 12 months. Additionally, five sub-studies investigate the effect of PFA on oesophageal safety, cerebral lesions, cardiac autonomic nervous system, durability of PVI as assessed during redo ablation procedures, and atrial and ventricular function. The study began on 27 December 2021 and concluded recruitment on 17 January 2024. Results will be available in mid-2025.

CONCLUSION

The BEAT PAROX-AF trial aims to provide critical insights into the optimal treatment approach for patients with paroxysmal AF.

Dual energy for pulmonary vein isolation using dual-energy focal ablation technology integrated with a three-dimensional mapping system: SmartfIRE 3-month results

AIMS

Contact force (CF)-sensing radiofrequency (RF) catheters with an ablation index have shown reproducible outcomes for the treatment of atrial fibrillation (AF) in large multicentre studies. A dual-energy (DE) focal CF catheter to deliver RF and unipolar/biphasic pulsed field ablation (PFA), integrated with a three-dimensional (3D) mapping system, can provide operators with additional flexibility. The SmartfIRE study assessed the safety and efficacy of this novel technology for the treatment of drug-refractory, symptomatic paroxysmal AF. Results at 3 months post-ablation are presented here.

METHODS AND RESULTS

Pulmonary vein isolation (PVI) was performed using a DE focal, irrigated CF-sensing catheter with the recommendation of PFA at posterior/inferior and RF ablation at the anterior/ridge/carina segments. Irrespective of energy, a tag size of 3 mm; an inter-tag distance ≤6 mm; a target index of 550 for anterior, roof, ridge, and carina; and a target index of 400 for posterior and inferior were recommended. Cavotricuspid isthmus ablation was permitted in patients with documented typical atrial flutter. The primary effectiveness endpoint was acute procedural success. The primary safety endpoint was the rate of primary adverse events (PAEs) within 7 days of the procedure. A prespecified patient subset underwent oesophageal endoscopy (EE; 72 h post-procedure), neurological assessment (NA; pre-procedure and discharge), and cardiac computed tomography (CT)/magnetic resonance angiogram (MRA) imaging (pre-procedure and 3 months post-procedure) for additional safety evaluation, and a mandatory remapping procedure (Day 75 ± 15) for PVI durability assessment. Of 149 patients enrolled between February and June 2023, 140 had the study catheter inserted (safety analysis set) and 137 had ablation energy delivered (per-protocol analysis set). The median (Q1/Q3) total procedure and fluoroscopy times were 108.0 (91.0/126.0) and 4.2 (2.3/7.7) min (n = 137). The acute procedural success rate was 100%. First-pass isolation was achieved in 89.1% of patients and 96.8% of veins. Cavotricuspid isthmus ablations were successfully performed in 12 patients [pulsed field (PF) only: 6, RF only: 5, and RF/PF: 1]. The PAE rate was 4.4% [6/137 patients; 2 pulmonary vein (PV) stenoses, 2 cardiac tamponades/perforations, 1 stroke, and 1 pericarditis]. No coronary artery spasm was reported. No oesophageal lesion was seen in the EE subset (0/31, 0%). In the NA subset (n = 30), microemboli lesions were identified in 2 patients (2/30, 6.7%), both of which were resolved at follow-up; only 1 was symptomatic (silent cerebral lesion, 3.3%). In the CT/MRA subset (n = 30), severe PV narrowing (of >70%) was detected in 2 patients (2/30, 6.7%; vein level 2/128, 1.6%), of whom 1 underwent dilatation and stenting and 1 was asymptomatic; both were associated with high index values and a small inter-tag distance. In the PV durability subset (n = 30), 100/115 treated PVs (87%) were durably isolated and 18/30 patients (60.0%) had all PVs durably isolated.

CONCLUSION

A DE focal CF catheter with 3D mapping integration showed a 100% acute success rate with an acceptable safety profile in the treatment of paroxysmal AF. Prespecified 3-month remapping showed notable PVI durability.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05752487.

Predictors of Success for Pulmonary Vein Isolation With Pulsed-Field Ablation Using a Variable-Loop Catheter With 3D Mapping Integration: Complete 12-Month Outcomes From inspIRE

BACKGROUND

We previously presented the safety and early efficacy of inspIRE study (Pulsed-Field Ablation (PFA) System for the Treatment of Paroxysmal Atrial Fibrillation by Irreversible Electroporation). With the study's conclusion, we report the outcomes of the full pivotal study cohort, with an additional analysis of predictors of success.

METHODS

InspIRE was a prospective, multicenter, single-arm clinical trial of drug-refractory paroxysmal atrial fibrillation. Pulmonary vein isolation was performed with a variable-loop circular catheter integrated with a 3-dimensional mapping system. Follow-up with 24-hour Holter was at 3, 6, and 12 months, as well as remote rhythm monitoring: weekly from 3 to 5 months, monthly from 6 to 12 months, and for symptoms. The primary effectiveness end point (PEE) was acute pulmonary vein isolation plus freedom from any atrial arrhythmia at 12 months. Additional subanalyses report predictors of PEE success.

RESULTS

The patient cohort included 186 patients: aged 59±10 years, female 30%, and CHA2DS2-VASc 1.3±1.2. The previously reported primary adverse event rate was 0%. One serious procedure-related adverse event, urinary retention, was reported. The PEE was achieved in 75.6% (95% CI, 69.5%-81.8%). The clinical success of freedom from symptomatic recurrence was 81.7% (95% CI, 76.1%-87.2%). Simulating a monitoring method used in standard real-world practice (without protocol-driven remote rhythm monitoring), this translates to a freedom from all and symptomatic recurrence of 85.8% (95% CI, 80.8%-90.9%) or 94.0% (95% CI, 90.6%-97.5%), respectively. Multivariate analyses revealed that left ventricular ejection fraction ≥60% (adjusted odds ratio, 0.30) and patients receiving ≥48 PFA applications (adjusted odds ratio, 0.28) were independent predictors of PEE success. Moreover, PEE success was 79.2% in patients who received ≥12 PFA applications/vein compared with 57.1% in patients receiving fewer PFA applications.

CONCLUSIONS

The inspIRE study confirms the safety and effectiveness of pulmonary vein isolation using the novel 3-dimensional mapping integrated circular loop catheter. An optimal number of PFA applications (≥48 total or ≥12 per vein) resulted in an improved 1-year success rate of ≈80%.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04524364.

Longer and better lives for patients with atrial fibrillation: the 9th AFNET/EHRA consensus conference

AIMS

Recent trial data demonstrate beneficial effects of active rhythm management in patients with atrial fibrillation (AF) and support the concept that a low arrhythmia burden is associated with a low risk of AF-related complications. The aim of this document is to summarize the key outcomes of the 9th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA).

METHODS AND RESULTS

Eighty-three international experts met in Münster for 2 days in September 2023. Key findings are as follows: (i) Active rhythm management should be part of the default initial treatment for all suitable patients with AF. (ii) Patients with device-detected AF have a low burden of AF and a low risk of stroke. Anticoagulation prevents some strokes and also increases major but non-lethal bleeding. (iii) More research is needed to improve stroke risk prediction in patients with AF, especially in those with a low AF burden. Biomolecules, genetics, and imaging can support this. (iv) The presence of AF should trigger systematic workup and comprehensive treatment of concomitant cardiovascular conditions. (v) Machine learning algorithms have been used to improve detection or likely development of AF. Cooperation between clinicians and data scientists is needed to leverage the potential of data science applications for patients with AF.

CONCLUSIONS

Patients with AF and a low arrhythmia burden have a lower risk of stroke and other cardiovascular events than those with a high arrhythmia burden. Combining active rhythm control, anticoagulation, rate control, and therapy of concomitant cardiovascular conditions can improve the lives of patients with AF.

Anticoagulation with edoxaban in patients with long atrial high-rate episodes ≥24 h

BACKGROUND AND AIMS

Patients with long atrial high-rate episodes (AHREs) ≥24 h and stroke risk factors are often treated with anticoagulation for stroke prevention. Anticoagulation has never been compared with no anticoagulation in these patients.

METHODS

This secondary pre-specified analysis of the Non-vitamin K antagonist Oral anticoagulants in patients with Atrial High-rate episodes (NOAH-AFNET 6) trial examined interactions between AHRE duration at baseline and anticoagulation with edoxaban compared with placebo in patients with AHRE and stroke risk factors. The primary efficacy outcome was a composite of stroke, systemic embolism, or cardiovascular death. The safety outcome was a composite of major bleeding and death. Key secondary outcomes were components of these outcomes and electrocardiogram (ECG)-diagnosed atrial fibrillation.

RESULTS

Median follow-up of 2389 patients with core lab-verified AHRE was 1.8 years. AHRE ≥24 h were present at baseline in 259/2389 patients (11%, 78 ± 7 years old, 28% women, CHA2DS2-VASc 4). Clinical characteristics were not different from patients with shorter AHRE. The primary outcome occurred in 9/132 patients with AHRE ≥24 h (4.3%/patient-year, 2 strokes) treated with anticoagulation and in 14/127 patients treated with placebo (6.9%/patient-year, 2 strokes). Atrial high-rate episode duration did not interact with the efficacy (P-interaction = .65) or safety (P-interaction = .98) of anticoagulation. Analyses including AHRE as a continuous parameter confirmed this. Patients with AHRE ≥24 h developed more ECG-diagnosed atrial fibrillation (17.0%/patient-year) than patients with shorter AHRE (8.2%/patient-year; P < .001).

CONCLUSIONS

This hypothesis-generating analysis does not find an interaction between AHRE duration and anticoagulation therapy in patients with device-detected AHRE and stroke risk factors. Further research is needed to identify patients with long AHRE at high stroke risk.

Prevalence and prognostic impact of bone disease in chronic heart failure with reduced ejection fraction

AIMS

Chronic heart failure is associated with a bone-catabolic state and increases the risk of osteoporosis and fractures. Prospective studies investigating the clinical relevance of bone disease in heart failure are lacking. We aimed to assess the prevalence and prognostic impact of osteoporosis and vertebral fractures (VFs) in chronic heart failure with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

Symptomatic outpatients with chronic heart failure and a previous diagnosis of overtly reduced left ventricular ejection fraction < 40% on stable, optimal HFrEF therapy and left ventricular ejection fraction < 50% at enrolment were included into a prospective single-centre study. Osteoporosis was determined with dual-energy X-ray absorptiometry and defined as a T-score ≤ 2.5 at any site. VFs were assessed using X-ray of both thoracic and lumbar spine applying the semiquantitative Genant score. We enrolled 205 patients (22% women), with a median age of 66 (IQR 58-74) years. Median left ventricular ejection fraction was 37 (IQR 30-43) % and median N-terminal pro B-type natriuretic peptide was 964 (IQR 363-2173) pg/mL. Osteoporosis, as defined by bone mineral density, and at least one VF were prevalent in 31 (15%) and 29 patients (14%). Osteoporosis or VF were present in 55 patients (27%) and 5 patients (2%) had both osteoporosis and a VF. During a median follow-up of 4.7 (IQR 4.0-5.3) years, 18 patients (9%) died due to cardiovascular (CV) cause, and 46 patients (22%) had a worsening heart failure (WHF) hospitalization. In multivariate Cox regression analyses, presence of VF independently predicted CV death (HR 2.82, 95% CI 1.04-7.65, P = 0.042), WHF hospitalizations (HR 2.39, 95% CI 1.18-4.82, P = 0.015), and a composite endpoint of CV death and WHF hospitalizations (HR 2.44, 95% CI 1.23-4.82, P = 0.011). Osteoporosis was not significantly associated with CV events.

CONCLUSIONS

In a prospective study, bone disease affected every fourth patient with HFrEF, and patients with VF at baseline had a two-fold risk of subsequent CV death or WHF hospitalization. Prevalent bone disease, particularly VF, should be considered as a clinically relevant comorbidity in HFrEF.

Cardiovascular Rehabilitation With a WCD-Data From the CR3 Study (Cardiac Rehab Retrospective Review)

PURPOSE

Patients at risk for sudden cardiac death may temporarily need a wearable cardioverter-defibrillator (WCD). Exercise-based cardiac rehabilitation (CR) has a class I recommendation in patients with cardiac disease. The aim of this study was to evaluate the safety and feasibility of undergoing CR with a WCD.

METHODS

We performed a retrospective analysis of all patients with a WCD who completed a CR in Austria (2010-2020).

RESULTS

Patients (n = 55, 60 ± 11 yr, 16% female) with a median baseline left ventricular ejection fraction (LVEF) of 36 (30, 41)% at the start of CR showed a daily WCD wearing duration of 23.4 (22, 24) hr. There were 2848 (8 [1, 26]/patient) automatic alarms and 340 (3 [1, 7]/patient) manual alarms generated. No shocks were delivered by the WCD during the CR period. One patient had recurrent hemodynamically tolerated ventricular tachycardias that were controlled with antiarrhythmic drugs.No severe WCD-associated adverse events occurred during the CR stay of a median 28 (28, 28) d. The fabric garment and the device setting needed to be adjusted in two patients to diminish inappropriate automatic alarms. Left ventricular ejection fraction after CR increased significantly to 42 (30, 44)% ( P < .001). Wearable cardioverter-defibrillator therapy was stopped due to LVEF restitution in 53% of patients. In 36% of patients an implantable cardioverter-defibrillator was implanted, 6% had LVEF improvement after coronary revascularization, one patient received a heart transplantation (2%), two patients discontinued WCD treatment at their own request (4%).

CONCLUSION

Completing CR is feasible and safe for WCD patients and may contribute positively to the restitution of cardiac function.

Evaluation of left ventricular and left atrial volumetric function from native MR multislice 4D flow magnitude data

OBJECTIVES

To assess the feasibility, precision, and accuracy of left ventricular (LV) and left atrial (LA) volumetric function evaluation from native magnetic resonance (MR) multislice 4D flow magnitude images.

MATERIALS & METHODS

In this prospective study, 60 subjects without signs or symptoms of heart failure underwent 3T native cardiac MR multislice 4D flow and bSSFP-cine realtime imaging. LV and LA volumetric function parameters were evaluated from 4D flow magnitude (4D flow-cine) and bSSFP-cine data using standard software to obtain end-diastolic volume (EDV), end-systolic volume (ESV), ejection-fraction (EF), stroke-volume (SV), LV muscle mass (LVM), LA maximum volume, LA minimum volume, and LA total ejection fraction (LATEF). Stroke volumes derived from both imaging methods were further compared to 4D pulmonary artery flow-derived net forward volumes (NFV). Methods were compared by correlation and Bland-Altman analysis.

RESULTS

Volumetric function parameters from 4D flow-cine and bSSFP-cine showed high to very high correlations (r = 0.83-0.98). SV, LA volumes and LATEF did not differ between methods. LV end-diastolic and end-systolic volumes were slightly underestimated (EDV: -2.9 ± 5.8 mL; ESV: -2.3 ± 3.8 mL), EF was slightly overestimated (EF: 0.9 ± 2.6%), and LV mass was considerably overestimated (LVM: 39.0 ± 11.4 g) by 4D flow-cine imaging. SVs from both methods correlated very highly with NFV (r = 0.91 in both cases) and did not differ from NFV.

CONCLUSION

Native multislice 4D flow magnitude data allows precise evaluation of LV and LA volumetric parameters; however, apart from SV, LV volumetric parameters demonstrate bias and need to be referred to their respective normal values.

CLINICAL RELEVANCE STATEMENT

Volumetric function assessment from native multislice 4D flow magnitude images can be performed with routinely used clinical software, facilitating the application of 4D flow as a one-stop-shop functional cardiac MR exam, providing consistent, simultaneously acquired, volume and flow data.

KEY POINTS

• Native multislice 4D flow imaging allows evaluation of volumetric left ventricular and atrial function parameters. • Left ventricular and left atrial function parameters derived from native multislice 4D flow data correlate highly with corresponding standard cine-derived parameters. • Multislice 4D flow-derived volumetric stroke volume and net forward volume do not differ.

Impact of Left Atrial Posterior Wall Ablation During Pulsed-Field Ablation for Persistent Atrial Fibrillation

BACKGROUND

Pulmonary vein isolation (PVI) alone is insufficient to treat many patients with persistent atrial fibrillation (PersAF). Adjunctive left atrial posterior wall (LAPW) ablation with thermal technologies has revealed lack of efficacy, perhaps limited by the difficulty in achieving lesion durability amid concerns of esophageal injury.

OBJECTIVES

This study aims to compare the safety and effectiveness of PVI + LAPW ablation vs PVI in patients with PersAF using pulsed-field ablation (PFA).

METHODS

In a retrospective analysis of the MANIFEST-PF (Multi-National Survey on the Methods, Efficacy, and Safety on the Post-approval Clinical Use of Pulsed Field Ablation) registry, we studied consecutive PersAF patients undergoing post-approval treatment with a pentaspline PFA catheter. The primary effectiveness outcome was freedom from any atrial arrhythmia of ≥30 seconds. Safety outcomes included the composite of acute and chronic major adverse events.

RESULTS

Of the 547 patients with PersAF who underwent PFA, 131 (24%) received adjunctive LAPW ablation. Compared to PVI-alone, patients receiving adjunctive LAPW ablation were younger (65 vs 67 years of age, P = 0.08), had a lower CHA2DS2-VASc score (2.3 ± 1.6 vs 2.6 ± 1.6, P = 0.08), and were more likely to receive electroanatomical mapping (48.1% vs 39.0%, P = 0.07) and intracardiac echocardiography imaging (46.1% vs 17.1%, P < 0.001). The 1-year Kaplan-Meier estimate for freedom from atrial arrhythmias was not statistically different between groups in the full (PVI + LAPW: 66.4%; 95% CI: 57.6%-74.4% vs PVI: 73.1%; 95% CI: 68.5%-77.2%; P = 0.68) and propensity-matched cohorts (PVI + LAPW: 71.7% vs PVI: 68.5%; P = 0.34). There was also no significant difference in major adverse events between the groups (2.2% vs 1.4%, respectively, P = 0.51).

CONCLUSIONS

In patients with PersAF undergoing PFA, as compared to PVI-alone, adjunctive LAPW ablation did not improve freedom from atrial arrhythmia at 12 months.

Impact of the evaluation method on 4D flow-derived diastolic transmitral and myocardial peak velocities: Comparison with echocardiography

PURPOSE

To compare agreement of different evaluation methods of magnetic resonance (MR) 4D flow-derived diastolic transmitral and myocardial peak velocities as well as their ratios, using echocardiography as reference.

METHODS

In this prospective study, 60 subjects without symptoms of cardiovascular disease underwent echocardiography and non-contrast 3 T MR 4D flow imaging of the heart. Early- (E) and late-diastolic (A) transmitral peak filling velocities were evaluated from 4D flow data using three different strategies: 1) at the mitral valve tips in short-axis orientation (SA-method), 2) between the mitral valve tips in 4-chamber orientation (4-chamber-method), and 3) as maximal velocities in the transmitral inflow volume (max-velocity-method). Septal, lateral and average early-diastolic myocardial peak velocities (e') were derived from the myocardial tissue in the vicinity of the mitral valve. 4D flow parameters were compared with echocardiography by correlation and Bland-Altman analysis.

RESULTS

All 4D flow-derived E, A and E/A values correlated with echocardiography (r = 0.65-0.73, 0.75-0.83 and 0.74-0.86, respectively). While the SA- and 4-chamber-methods substantially underestimated E and A compared to echocardiography (p < 0.001), the max-velocity-method provided E (p = 0.13) and E/A (p = 0.07) without significant bias. Septal, lateral and average e' from 4D flow as well as the max-velocity-method-derived E/e' correlated with echocardiographic measurements (r = 0.64-0.81) and showed no significant bias (p = 0.26-0.54).

CONCLUSION

MR 4D flow imaging allows precise and accurate evaluation of transmitral and myocardial peak velocities for characterization of LV diastolic function without significant bias to echocardiography, when transmitral velocities are assessed from the transmitral inflow volume. This enables the use of validated echocardiography threshold values.

Zero-fluoroscopy ablation with multielectrode pulse field ablation system: Case series

Pulse field ablation (PFA) is a novel nonthermal ablation modality for treatment of atrial fibrillation. While mostly lacking 3D electroanatomical mapping integration, reported radiation doses in procedures using multielectrode PFA catheters are relatively high. We report a first case series of three patients where a zero-fluoroscopy approach by intracardiac echocardiography was utilized and present a possible workflow for zero-fluoroscopy ablation with the Farapulse PFA system.

Detection of brain lesions after catheter ablation depends on imaging criteria: insights from AXAFA-AFNET 5 trial

AIMS

Left atrial catheter ablation is well established in patients with symptomatic atrial fibrillation (AF) but associated with risk of embolism to the brain. The present analysis aims to assess the impact of diffusion-weighted imaging (DWI) slice thickness on the rate of magnetic resonance imaging (MRI)-detected ischaemic brain lesions after ablation.

METHODS AND RESULTS

AXAFA-AFNET 5 trial (NCT02227550) participants underwent MRI using high-resolution (hr) DWI (slice thickness: 2.5-3 mm) and standard DWI (slice thickness: 5-6 mm) within 3-48 h after ablation. In 321 patients with analysable brain MRI (mean age 64 years, 33% female, median CHA2DS2-VASc 2), hrDWI detected at least one acute brain lesion in 84 (26.2%) patients and standard DWI in 60 (18.7%; P < 0.01) patients. High-resolution diffusion-weighted imaging detected more lesions compared to standard DWI (165 vs. 104; P < 0.01). The degree of agreement for lesion confirmation using hrDWI vs. standard DWI was substantial (κ = 0769). Comparing the proportion of DWI-detected lesions, lesion distribution, and total lesion volume per patient, there was no difference in the cohort of participants undergoing MRI at 1.5 T (n = 52) vs. 3 T (n = 269).

CONCLUSION

The pre-specified AXAFA-AFNET 5 sub-analysis revealed significantly increased rates of MRI-detected acute brain lesions using hrDWI instead of standard DWI in AF patients undergoing ablation. In comparison to DWI slice thickness, MRI field strength had a no significant impact in the trial. Comparing the varying rates of ablation-related MRI-detected brain lesions across previous studies has to consider these technical parameters. Future studies should use hrDWI, as feasibility was demonstrated in the multicentre AXAFA-AFNET 5 trial.

Clinical Outcomes by Sex After Pulsed Field Ablation of Atrial Fibrillation

Importance

Previous studies evaluating the association of patient sex with clinical outcomes using conventional thermal ablative modalities for atrial fibrillation (AF) such as radiofrequency or cryoablation are controversial due to mixed results. Pulsed field ablation (PFA) is a novel AF ablation energy modality that has demonstrated preferential myocardial tissue ablation with a unique safety profile.

Objective

To compare sex differences in patients undergoing PFA for AF in the Multinational Survey on the Methods, Efficacy, and Safety on the Postapproval Clinical Use of Pulsed Field Ablation (MANIFEST-PF) registry.

Design, Setting, and Participants

This was a retrospective cohort study of MANIFEST-PF registry data, which included consecutive patients undergoing postregulatory approval treatment with PFA to treat AF between March 2021 and May 2022 with a median follow-up of 1 year. MANIFEST-PF is a multinational, retrospectively analyzed, prospectively enrolled patient-level registry including 24 European centers. The study included all consecutive registry patients (age ≥18 years) who underwent first-ever PFA for paroxysmal or persistent AF.

Exposure

PFA was performed on patients with AF. All patients underwent pulmonary vein isolation and additional ablation, which was performed at the discretion of the operator.

Main Outcomes and Measures

The primary effectiveness outcome was freedom from clinically documented atrial arrhythmia for 30 seconds or longer after a 3-month blanking period. The primary safety outcome was the composite of acute (<7 days postprocedure) and chronic (>7 days) major adverse events (MAEs).

Results

Of 1568 patients (mean [SD] age, 64.5 [11.5] years; 1015 male [64.7%]) with AF who underwent PFA, female patients, as compared with male patients, were older (mean [SD] age, 68 [10] years vs 62 [12] years; P < .001), had more paroxysmal AF (70.2% [388 of 553] vs 62.4% [633 of 1015]; P = .002) but had fewer comorbidities such as coronary disease (9% [38 of 553] vs 15.9% [129 of 1015]; P < .001), heart failure (10.5% [58 of 553] vs 16.6% [168 of 1015]; P = .001), and sleep apnea (4.7% [18 of 553] vs 11.7% [84 of 1015]; P < .001). Pulmonary vein isolation was performed in 99.8% of female (552 of 553) and 98.9% of male (1004 of 1015; P = .90) patients. Additional ablation was performed in 22.4% of female (124 of 553) and 23.1% of male (235 of 1015; P = .79) patients. The 1-year Kaplan-Meier estimate for freedom from atrial arrhythmia was similar in male and female patients (79.0%; 95% CI, 76.3%-81.5% vs 76.3%; 95% CI, 72.5%-79.8%; P = .28). There was also no significant difference in acute major AEs between groups (male, 1.5% [16 of 1015] vs female, 2.5% [14 of 553]; P = .19).

Conclusion and Relevance

Results of this cohort study suggest that after PFA for AF, there were no significant sex differences in clinical effectiveness or safety events.

Extracellular Matrix Protein-1 as a Mediator of Inflammation-Induced Fibrosis After Myocardial Infarction

Irreversible fibrosis is a hallmark of myocardial infarction (MI) and heart failure. Extracellular matrix protein-1 (ECM-1) is up-regulated in these hearts, localized to fibrotic, inflammatory, and perivascular areas. ECM-1 originates predominantly from fibroblasts, macrophages, and pericytes/vascular cells in uninjured human and mouse hearts, and from M1 and M2 macrophages and myofibroblasts after MI. ECM-1 stimulates fibroblast-to-myofibroblast transition, up-regulates key fibrotic and inflammatory pathways, and inhibits cardiac fibroblast migration. ECM-1 binds HuCFb cell surface receptor LRP1, and LRP1 inhibition blocks ECM-1 from stimulating fibroblast-to-myofibroblast transition, confirming a novel ECM-1-LRP1 fibrotic signaling axis. ECM-1 may represent a novel mechanism facilitating inflammation-fibrosis crosstalk.

MR 4D flow-derived left atrial acceleration factor for differentiating advanced left ventricular diastolic dysfunction

OBJECTIVES

The magnetic resonance (MR) 4D flow imaging-derived left atrial (LA) acceleration factor α was recently introduced as a means to non-invasively estimate LA pressure. We aimed to investigate the association of α with the severity of left ventricular (LV) diastolic dysfunction using echocardiography as the reference method.

METHODS

Echocardiographic assessment of LV diastolic function and 3-T cardiac MR 4D flow imaging were prospectively performed in 94 subjects (44 male/50 female; mean age, 62 ± 12 years). LA early diastolic peak outflow velocity (vE), systolic peak inflow velocity (vS), and early diastolic peak inflow velocity (vD) were evaluated from 4D flow data. α was calculated from α = vE / [(vS + vD) / 2]. Mean parameter values were compared by t-test; diagnostic performance of α in predicting diastolic (dys)function was investigated by receiver operating characteristic curve analysis.

RESULTS

Mean α values were 1.17 ± 0.14, 1.20 ± 0.08, 1.33 ± 0.15, 1.77 ± 0.18, and 2.79 ± 0.69 for grade 0 (n = 51), indeterminate (n = 9), grade I (n = 13), grade II (n = 13), and grade III (n = 8) LV diastolic (dys)function, respectively. α differed between subjects with non-advanced (grade < II) and advanced (grade ≥ II) diastolic dysfunction (1.20 ± 0.15 vs. 2.16 ± 0.66, p < 0.001). The area under the curve (AUC) for detection of advanced diastolic dysfunction was 0.998 (95% CI: 0.958-1.000), yielding sensitivity of 100% (95% CI: 84-100%) and specificity of 99% (95% CI: 93-100%) at cut-off α ≥ 1.58. The AUC for differentiating grade III diastolic dysfunction was also 0.998 (95% CI: 0.976-1.000) at cut-off α ≥ 2.14.

CONCLUSION

The 4D flow-derived LA acceleration factor α allows grade II and grade III diastolic dysfunction to be distinguished from non-advanced grades as well as from each other.

CLINICAL RELEVANCE STATEMENT

As a single continuous parameter, the 4D flow-derived LA acceleration factor α shows potential to simplify the multi-parametric imaging algorithm for diagnosis of advanced LV diastolic dysfunction, thereby identifying patients at increased risk for cardiovascular events.

KEY POINTS

• Detection of advanced diastolic dysfunction is typically performed using a complex, multi-parametric approach. • The 4D flow-derived left atrial acceleration factor α alone allows accurate detection of advanced left ventricular diastolic dysfunction. • As a single continuous parameter, the left atrial acceleration factor α could simplify the diagnosis of advanced diastolic dysfunction.

Outcomes of ECLS-SHOCK Eligibility Criteria Applied to a Real-World Cohort

BACKGROUND

Cardiogenic shock (CS) exhibits high (~50%) in-hospital mortality. The recently published Extracorporeal life Support in Cardiogenic Shock (ECLS-SHOCK) trial demonstrated the neutral effects of the use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) on all-cause death, as well as on all secondary outcomes in subjects presenting with myocardial-infarction (MI)-related CS. Here, we compared ECLS-SHOCK eligibility criteria with a real-world cohort of CS patients.

METHODS AND RESULTS

ECLS-SHOCK eligibility criteria were applied to a prospective single-center CS registry (the PREPARE CS registry) consisting of 557 patients who were consecutively admitted to the catheterization laboratory (cath lab) of the Medical University of Graz, Austria, due to CS (SCAI C-E). Overall use of mechanical circulatory support (MCS) in this cohort was 19%. Sixty-nine percent of the entire cohort had MI-related CS, 38% of whom would have met ECLS-SHOCK eligibility criteria, thus representing only 27% of the PREPARE CS registry. Exclusion from the ECLS-SHOCK trial was based on patients with initial lactate values below 3 mmol/L (n = 168; 43.6%), aged over 80 years (n = 65; 16.9%), and with a duration of cardiopulmonary resuscitation (CPR) exceeding 45 min (n = 22; 5.7%). The 30-day mortality of patients of the PREPARE CS registry who met the ECLS-SHOCK eligibility criteria was 57.0%, compared to 48.4% of patients in the ECLS-SHOCK trial. The patients' baseline characteristics, however, differed considerably with respect to type of infarction, age, and gender.

CONCLUSIONS

In a real-world cohort of patients with MI-related CS, only 38% of patients met the eligibility criteria of the ECLS-SHOCK trial. Thus, the impact of the use of VA-ECMO on outcome parameters in MI-related CS, as observed in the ECLS-SHOCK trial, may differ in a more heterogeneous real-world CS population of the PREPARE CS registry.

No Effect of Continued Antiarrhythmic Drug Treatment on Top of Optimized Pulmonary Vein Isolation in Patients With Persistent Atrial Fibrillation: Results From the POWDER-AF2 Trial

BACKGROUND

In patients with persistent atrial fibrillation (PersAF), catheter ablation aiming for pulmonary vein isolation (PVI) is associated with moderate clinical effectiveness. We investigated the benefit of continuing previously ineffective class 1C or 3 antiarrhythmic drug therapy (ADT) in the setting of a standardized PVI-only ablation strategy.

METHODS

In this multicenter, randomized controlled study, patients with PersAF (≥7 days and <12 months) despite ADT were prospectively randomized 1:1 to PVI with ADT continued versus discontinued beyond the blanking period (ADT ON versus ADT OFF). Standardized catheter ablation was performed aiming for durable isolation with stable, contiguous, and optimized radio frequency applications encircling the pulmonary veins (CLOSE protocol). Clinical visits and 1-to-7-day Holter were performed at 3, 6, and 12 months. The primary end point was any documented atrial tachyarrhythmia lasting >30 seconds beyond 3 months. Prospectively defined secondary end points included repeat ablations, unscheduled arrhythmia-related visits, and quality of life among groups.

RESULTS

Of 200 PersAF patients, 98 were assigned to ADT OFF and 102 to ADT ON. The longest atrial fibrillation episode qualifying for PersAF was 28 (10-90) versus 30 (11-90) days. Clinical characteristics and procedural characteristics were similar. Recurrence of atrial tachyarrhythmia was comparable in both groups (20% OFF versus 21.2% ON). No differences were observed in repeat ablations and unscheduled arrhythmia-related visits. Marked improvement in quality of life was observed in both groups.

CONCLUSIONS

In patients with PersAF, there is no benefit in continuing previously ineffective ADT beyond the blanking period after catheter ablation. The high success rate of PVI-only might be explained by the high rate of durable isolation after optimized PVI and the early stage of PersAF (POWDER-AF2).

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03437356.

Electrophysiological findings during re-do procedures after single-shot pulmonary vein isolation for atrial fibrillation with pulsed field ablation

BACKGROUND

Pulsed field ablation (PFA) is a novel ablation technology recently adopted in the treatment of atrial fibrillation (AF). Currently, little is known about the durability of PFA ablation lesions.

METHODS

We investigated patients who underwent redo-ablation due to recurrent AF/atrial-flutter or tachycardia (AFL/AT) following PVI with PFA. We report electrophysiological findings and ablation strategy during redo-ablation.

RESULTS

Of 447 patients undergoing index PVI with PFA, 14 patients (age: 61.9±10.8 years; 7 (50.0%) males; left atrial volume index (n=10): 39.4±14.6 mL/m2) were referred for redo-ablation. Initial indication was paroxysmal-AF in 7 patients, persistent-AF in 6 and long-standing-persistent-AF in one patient. Mean time-to-recurrence was 4.9±1.9 months. Three patients received additional posterior-wall-isolation during index PFA. Twelve (85.7%) patients suffered AF recurrence and 5/12 had concomitant AFL. In the remaining 2 patients, one had a (box-dependent) AFL, and one had an atypical AT. No patients had all PVs reconnected. Reconnection in zero, one, two or three PVs was found in 35.7%, 21.4%, 14.3%, and 28.6% of patients, respectively. All 7 patients with zero or one reconnection with AF recurrence received additional/repeat posterior-wall-isolation during re-ablation, while in the others, PVs were re-isolated. Patients with only AFL/AT had no reconnection of PVs, and the substrate was successfully ablated.

CONCLUSIONS

Durable PVI (all PV's isolated) was observed in over one-third of patients at re-do. The predominant recurrent arrhythmia following PVI-only was AF. Concomitant (35.7%) or isolated (14.3%) AFL/AT recurrence was observed in 50% of patients.

Anticoagulation with Edoxaban in Patients with Atrial High-Rate Episodes

BACKGROUND

Device-detected atrial high-rate episodes (AHREs) are atrial arrhythmias detected by implanted cardiac devices. AHREs resemble atrial fibrillation but are rare and brief. Whether the occurrence of AHREs in patients without atrial fibrillation (as documented on a conventional electrocardiogram [ECG]) justifies the initiation of anticoagulants is not known.

METHODS

We conducted an event-driven, double-blind, double-dummy, randomized trial involving patients 65 years of age or older who had AHREs lasting for at least 6 minutes and who had at least one additional risk factor for stroke. Patients were randomly assigned in a 1:1 ratio to receive edoxaban or placebo. The primary efficacy outcome was a composite of cardiovascular death, stroke, or systemic embolism, evaluated in a time-to-event analysis. The safety outcome was a composite of death from any cause or major bleeding.

RESULTS

The analysis population consisted of 2536 patients (1270 in the edoxaban group and 1266 in the placebo group). The mean age was 78 years, 37.4% were women, and the median duration of AHREs was 2.8 hours. The trial was terminated early, at a median follow-up of 21 months, on the basis of safety concerns and the results of an independent, informal assessment of futility for the efficacy of edoxaban; at termination, the planned enrollment had been completed. A primary efficacy outcome event occurred in 83 patients (3.2% per patient-year) in the edoxaban group and in 101 patients (4.0% per patient-year) in the placebo group (hazard ratio, 0.81; 95% confidence interval [CI], 0.60 to 1.08; P = 0.15). The incidence of stroke was approximately 1% per patient-year in both groups. A safety outcome event occurred in 149 patients (5.9% per patient-year) in the edoxaban group and in 114 patients (4.5% per patient-year) in the placebo group (hazard ratio, 1.31; 95% CI, 1.02 to 1.67; P = 0.03). ECG-diagnosed atrial fibrillation developed in 462 of 2536 patients (18.2% total, 8.7% per patient-year).

CONCLUSIONS

Among patients with AHREs detected by implantable devices, anticoagulation with edoxaban did not significantly reduce the incidence of a composite of cardiovascular death, stroke, or systemic embolism as compared with placebo, but it led to a higher incidence of a composite of death or major bleeding. The incidence of stroke was low in both groups. (Funded by the German Center for Cardiovascular Research and others; NOAH-AFNET 6 ClinicalTrials.gov number, NCT02618577; ISRCTN number, ISRCTN17309850.).

Prevention of Early Sudden Cardiac Death after Myocardial Infarction Using the Wearable Cardioverter Defibrillator-Results from a Real-World Cohort

BACKGROUND

After acute myocardial infarction (AMI), patients are at risk of sudden cardiac death. The VEST trial failed to show a reduction in arrhythmic mortality in AMI patients with an LVEF ≤ 35% prescribed with a WCD, having a lower-than-expected WCD wearing compliance.

OBJECTIVES

The aim was to investigate on outcomes of patients in a real-world Austrian cohort with good compliance.

METHODS

A retrospective analysis of all eligible Austrian WCD patients according to the VEST trial inclusion and exclusion criteria between 2010 and 2020 was performed.

RESULTS

In total, 105 Austrian patients (64 ± 11 years, 12% female; LVEF 28 ± 6%) received a WCD for a median of 69 (1; 277) days after AMI (wearing duration 23.5 (0; 24) hours/day). Within the first 90 days, 4/105 (3.8%) patients received 9 appropriate shocks (2 (1; 5) shocks). No inappropriate shocks were delivered, and 3/105 (2.9%) patients died during follow-up. Arrhythmic mortality (1.9% Austria vs. 1.6% VEST, p = 0.52), as well as all-cause mortality (2.9% vs. 3.1%, p = 0.42) was comparable in both cohorts.

CONCLUSIONS

The WCD is a safe treatment option in a highly selected cohort of patients with LVEF ≤ 35% after AMI. However, despite excellent WCD wearing duration in our cohort, the arrhythmic mortality rate was not significantly different.

AMH in Males: Effects of Body Size and Composition on Serum AMH Levels

Serum concentrations of anti-Müllerian hormone (AMH) have been found to decrease with increasing body mass index (BMI) in many studies. It is not yet clear whether this stems from an adverse effect of adiposity on AMH production, or from dilution due to the greater blood volume that accompanies a larger body size. To investigate a possible hemodilution effect, we explored the relationships between serum AMH levels and different parameters of body composition using linear regression models in a cohort of adult males. Body weight, lean mass (LM), and body surface area (BSA) were found to be better predictors of AMH than measures of adiposity, such as BMI or fat mass. Since both LM and BSA correlate with plasma volume better than adipose tissue, we conclude that hemodilution of AMH does occur in adult males and should be considered for normalization in future studies.

Photoplethysmography-documented atrial fibrillation in the first week after catheter ablation is associated with lower success rates

Aims

To test the feasibility of postprocedural photoplethysmography (PPG) rhythm telemonitoring during the first week after atrial fibrillation (AF) ablation and its predictive value for later AF recurrence.

Methods

PPG rhythm telemonitoring during the first week after the ablation procedure was offered to a total of 382 consecutive patients undergoing AF ablation. Patients were instructed to perform 1 min PPG recordings by a mobile health application 3 times per day and in case of symptoms. Clinicians assessed the PPG tracings via a secured cloud and the information was remotely integrated into the therapeutic pathway via teleconsultation (TeleCheck-AF approach).

Results

119 patients (31%) agreed to perform PPG rhythm telemonitoring after ablation. Patients included in the TeleCheck-AF approach were younger compared to those who declined participation (58 ± 10 vs. 62 ± 10 years, p < 0.001). Median follow up duration was 544 (53-883) days. 27% of patients had PPG tracings suggestive of AF in the week following the ablation. In 24% of patients, the integration of PPG rhythm telemonitoring resulted in a remote clinical intervention during teleconsultation. During follow-up of one year, 33% of patients had ECG-documented AF recurrences. PPG recordings suggestive of AF in the week after ablation were predictive of late recurrences (p < 0.001).

Conclusion

PPG rhythm telemonitoring during the first week after AF ablation often triggered clinical interventions. Due to its high availability, PPG-based follow-up actively involving patients after AF ablation may close a diagnostic and prognostic gap in the blanking period and increase active patient-involvement.

Automated external defibrillator delivery by drone in mountainous regions to support basic life support - A simulation study

Background

Out-of-hospital cardiac arrest (OHCA) is associated with poor survival rates. Factors that may enable survival include cardiopulmonary resuscitation (CPR) initiated by bystanders and early use of an automated external defibrillator (AED). This explorative simulation study was conceptualized to test the feasibility of a semi-autonomously operating drone that delivers an AED to a remote emergency location and its bystander-use.

Methods

Ten paramedics and nineteen laypersons were confronted with a manikin simulating an OHCA as single bystanders within a field test located in a mountainous region between Austria and Slovenia. The scenario included a mock-call to the local emergency response center that dispatched a drone towards the caller's GPS coordinates and supported the ongoing CPR. The outcomes were the successful delivery of the AED, the time to the first shock, hands-off times, and the overall performance of the CPR.

Results

The AED was delivered by drone and used in all 29 scenarios without serious adverse events. The flight time of the drone was in median 5:20 (range: 1:35-8:19) minutes. The paramedics delivered the first shock after a mean of 12:15 ± 2:03 min and hands-off times were 50 ± 22 s. The laypersons delivered the first shock after 14:04 ± 2:10 min and hands-off times were 2:11 ± 0:39 min. All participants felt confident in the handling of the delivered AED.

Conclusion

The delivery and usage of an AED via a semi-autonomously flying drone in a remote region is feasible. This approach can lead to early administration of shocks.

Safety and Effectiveness of Pulsed Field Ablation to Treat Atrial Fibrillation: One-Year Outcomes From the MANIFEST-PF Registry

BACKGROUND

Pulsed field ablation is a novel nonthermal cardiac ablation modality using ultra-rapid electrical pulses to cause cell death by a mechanism of irreversible electroporation. Unlike the traditional ablation energy sources, pulsed field ablation has demonstrated significant preferentiality to myocardial tissue ablation, and thus avoids certain thermally mediated complications. However, its safety and effectiveness remain unknown in usual clinical care.

METHODS

MANIFEST-PF (Multi-National Survey on the Methods, Efficacy, and Safety on the Post-Approval Clinical Use of Pulsed Field Ablation) is a retrospective, multinational, patient-level registry wherein patients at each center were prospectively included in their respective center registries. The registry included all patients undergoing postapproval treatment with a multielectrode 5-spline pulsed field ablation catheter to treat atrial fibrillation (AF) between March 1, 2021, and May 30, 2022. The primary effectiveness outcome was freedom from clinical documented atrial arrhythmia (AF/atrial flutter/atrial tachycardia) of ≥30 seconds on the basis of electrocardiographic data after a 3-month blanking period (on or off antiarrhythmic drugs). Safety outcomes included the composite of acute (<7 days postprocedure) and latent (>7 days) major adverse events.

RESULTS

At 24 European centers (77 operators) pulsed field ablation was performed in 1568 patients with AF: age 64.5±11.5 years, female 35%, paroxysmal/persistent AF 65%/32%, CHA₂DS₂-VASc 2.2±1.6, median left ventricular ejection fraction 60%, and left atrial diameter 42 mm. Pulmonary vein isolation was achieved in 99.2% of patients. After a median (interquartile range) follow-up of 367 (289-421) days, the 1-year Kaplan-Meier estimate for freedom from atrial arrhythmia was 78.1% (95% CI, 76.0%-80.0%); clinical effectiveness was more common in patients with paroxysmal AF versus persistent AF (81.6% versus 71.5%; P=0.001). Acute major adverse events occurred in 1.9% of patients.

CONCLUSIONS

In this large observational registry of the postapproval clinical use of pulsed field technology to treat AF, catheter ablation using pulsed field energy was clinically effective in 78% of patients with AF.

Antiarrhythmic Drug Dosing in Children-Review of the Literature

Antiarrhythmic drugs represent a mainstay of pediatric arrhythmia treatment. However, official guidelines and consensus documents on this topic remain scarce. There are rather uniform recommendations for some medications (including adenosine, amiodarone, and esmolol), while there are only very broad dosage recommendations for others (such as sotalol or digoxin). To prevent potential uncertainties and even mistakes with regard to dosing, we summarized the published dosage recommendations for antiarrhythmic drugs in children. Because of the wide variations in availability, regulatory approval, and experience, we encourage centers to develop their own specific protocols for pediatric antiarrhythmic drug therapy.

Urinary C-Peptide to Creatinine Ratio (UCPCR) as Indicator for Metabolic Risk in Apparently Healthy Adults-A BioPersMed Cohort Study

Background: C-peptide is produced in equimolar amounts with insulin from pancreatic beta cells, and thus is a fundamental biomarker for beta cell function. A non-invasive urinary C-peptide-to-creatinine ratio (UCPCR) has attracted attention as a biomarker for metabolic conditions. However, the UCPCR as an indicative risk predictor for prediabetes is still being investigated. Methods: We aimed to characterize UCPCRs in healthy people using American Diabetes Association (ADA) criteria and to evaluate their metabolic outcomes over time. A total of 1022 participants of the Biomarkers in Personalized Medicine cohort (BioPersMed) were screened for this study. Totals of 317 healthy with normal glucose metabolism, 87 prediabetic, and 43 diabetic subjects were included. Results: Prediabetic participants had a significantly higher UCPCR median value than healthy participants (p < 0.05). Dysglycaemia of healthy baseline participants was measured twice over 4.5 ± 0.9 years; 25% and 30% were detected with prediabetes during follow-ups, predicted by UCPCR both for the first (p < 0.05) and the second visit (p < 0.05), respectively. This is in good agreement with the negative predictive UCPCR value of 60.2% based on logistic regression. UCPCR levels were equal in both sexes. Conclusion: UCPCR measurements provide an indicative approach for metabolic risk, representing a potential use for prevention and monitoring of impaired glucose metabolism.

Impact of cryoballoon application abortion due to phrenic nerve injury on reconnection rates: a YETI subgroup analysis

AIMS

Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an effective treatment for atrial fibrillation (AF). The most frequent complication during CB-based PVI is right-sided phrenic nerve injury (PNI) which is leading to premature abortion of the freeze cycle. Here, we analysed reconnection rates after CB-based PVI and PNI in a large-scale population during repeat procedures.

METHODS AND RESULTS

In the YETI registry, a total of 17 356 patients underwent CB-based PVI in 33 centres, and 731 (4.2%) patients experienced PNI. A total of 111/731 (15.2%) patients received a repeat procedure for treatment of recurrent AF. In 94/111 (84.7%) patients data on repeat procedures were available. A total of 89/94 (94.7%) index pulmonary veins (PVs) have been isolated during the initial PVI. During repeat procedures, 22 (24.7%) of initially isolated index PVs showed reconnection. The use of a double stop technique did non influence the PV reconnection rate (P = 0.464). The time to PNI was 140.5 ± 45.1 s in patients with persistent PVI and 133.5 ± 53.8 s in patients with reconnection (P = 0.559). No differences were noted between the two populations in terms of CB temperature at the time of PNI (P = 0.362). The only parameter associated with isolation durability was CB temperature after 30 s of freezing. The PV reconnection did not influence the time to AF recurrence.

CONCLUSION

In patients with cryoballon application abortion due to PNI, a high rate of persistent PVI rate was found at repeat procedures. Our data may help to identify the optimal dosing protocol in CB-based PVI procedures.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT03645577?term=YETI&cntry=DE&draw=2&rank=1 ClinicalTrials.gov Identifier: NCT03645577.

Paroxysmal AF Ablation Using a Novel Variable-Loop Biphasic Pulsed Field Ablation Catheter Integrated With a 3D Mapping System: 1-Year Outcomes of the Multicenter inspIRE Study

Background - The inspIRE study evaluated safety and effectiveness of a fully integrated biphasic pulsed field ablation (PFA) system with a variable loop circular catheter for the treatment of drug-refractory paroxysmal atrial fibrillation (AF). Methods - Subjects underwent pulmonary vein isolation (PVI) with the PFA system, using at least 12 applications per vein; adenosine/isoproterenol was administered to confirm entrance block. Wave I assessed initial safety, including for esophageal lesions, silent cerebral lesions (SCLs), and PV stenosis. Wave II (pivotal phase) tested i) primary safety - incidence of early onset primary adverse events (PAEs), and primary effectiveness - confirmed PVI with freedom from documented atrial arrhythmia at 12-months (12M). The study design specified an interim analysis to determine early success once 30 subjects reached 12M follow-up (FU) and all subjects reached 3M FU. Results - Across 13 centers in Europe/Canada, 226 subjects were enrolled, met criteria for safety and effectiveness evaluations and received PFA (Wave I: 40; Wave II: 186). Wave I demonstrated no esophageal thermal lesions or PV stenosis. Among 39 subjects with cerebral MRI, SCLs were detected in 4 of the first 6 subjects, after which workflow enhancements, including a 10s pause between PFA applications was implemented; subsequently, only 4 of 33 subjects had SCLs. In the Wave II phase, no PAE was reported. Upon declaring early success, 83 subjects reached 12M FU. With 100% entrance block, PVI without acute reconnection was achieved in 97.1% of targeted veins. For Wave II, the primary effectiveness endpoint per Kaplan Meier at the time of interim analysis was 70.9%; 12M freedom from symptomatic AF/atrial flutter/atrial tachycardia recurrence and repeat ablation was 78.9% and 92.3%, respectively. Total procedure and transpired PFA times were 70.1 ± 27.7 min and 26.7 ± 14.0 min, respectively. Conclusions - The inspIRE trial confirmed the safety and effectiveness of the novel mapping-integrated PFA system.

Assessing the weak links - Necessity and impact of regional cardiac arrest awareness campaigns for laypersons

Introduction

Public knowledge of out-of-hospital cardiac arrest (OHCA), and initiation of basic life support (BLS) is crucial to increase survival in OHCA.

Methods

The study analysed the knowledge and willingness to perform BLS of laypersons passing an AED at a public train station. Interviewees were recruited at two time points before and after a four year-long structured regional awareness campaign, which focused on call, compress, shock in a mid-size European city (270,000 inhabitants). Complete BLS was defined as multiple responses for call for help; initiation of chest compressions; and usage of an AED, without mentioning recovery position. Minimal BLS was defined as call for help and initiation of chest compressions.

Results

A total of 784 persons were interviewed, 257 at baseline and 527 post-campaign. Confronted with a fictional OHCA, at baseline 8.5% of the interviewees spontaneously mentioned actions for complete BLS and 17.9% post-campaign (p = 0.009). An even larger increase in knowledge was seen in minimal BLS (34.6% vs 60.6%, p < 0.001).

Conclusion

After a regional cardiac arrest awareness campaign, we found an increase in knowledge of BLS actions in the lay public. However, our investigation revealed severe gaps in BLS knowledge, possibly resulting in weak first links of the chain of survival.

Very High-Power Ablation for Contiguous Pulmonary Vein Isolation: Results From the Randomized POWER PLUS Trial

BACKGROUND

Very high-power, short-duration (90-W/4-second) ablation for pulmonary vein isolation (PVI) may reduce procedural times. However, shorter applications with higher power may impact lesion quality.

OBJECTIVES

In this multicenter, randomized controlled trial, we compared procedural efficiency, efficacy, and safety of PVI using 90-W/4-second ablation to 35/50-W ablation.

METHODS

Patients with paroxysmal or persistent atrial fibrillation undergoing first-time PVI were randomized to pulmonary vein encirclement with contiguous applications using very high-power, short-duration applications (90 W over 4 seconds) or 35/50-W applications (titrated up to ablation index >550 anteriorly and >400 posteriorly). Prospective endpoints were procedural efficiency (procedure time and first-pass isolation), safety (including esophageal endoscopic evaluation), and 6-month effectiveness using repetitive Holter monitoring.

RESULTS

One hundred eighty patients were randomized, 90 to the 90-W group (mean age: 64.2 ± 8.9 years) and 90 to the 35/50-W group (mean age: 62.3 ± 10.8 years). Procedural time was shorter in the 90-W group vs the 35/50-W group (70 [interquartile range: 60-80] vs 75 [interquartile range: 65-88.3] minutes; P = 0.009). A nonsignificant trend towards lower rates of first-pass isolation was seen in the 90-W group (83.9% vs 90%; P = 0.0852). No major complications were observed in both groups with esophageal injury occurring in 1 patient per group. At 6 months, 17% of patients in the 90-W group vs 15% in the 35/50-W group experienced recurrent arrhythmia (P = 0.681).

CONCLUSIONS

Contiguous ablation using very high-power, short-duration applications results in a significant but modest reduction in procedure time with similar safety and 6-month efficacy vs a conventional approach. A hybrid approach combining both ablation modalities might be the most optimal strategy. (POWER PLUS [Very High Power Ablation in Patients With Atrial Fibrillation Schedule for a First Pulmonary Vein Isolation]; NCT04784013).

Patient selection, peri-procedural management, and ablation techniques for catheter ablation of atrial fibrillation: an EHRA survey

Catheter ablation (CA) of atrial fibrillation (AF) is the therapy of choice for the maintenance of sinus rhythm in patients with symptomatic AF. Time towards interventional treatment and peri-procedural management of patients undergoing AF ablation may vary in daily practice. The scope of this European Heart Rhythm Association (EHRA) survey was to report the current clinical practice regarding the management of patients undergoing AF ablation and physician's adherence to the European Society of Cardiology Guidelines and the EHRA/HRS/ECAS expert consensus statement on the CA for AF. This physician-based survey was conducted among EHRA members, using an internet-based questionnaire developed by the EHRA Scientific Initiatives Committee. A total of 258 physicians participated in the survey. In patients with paroxysmal or persistent AF, 42 and 9% of the physicians would routinely perform AF ablation as first-line therapy respectively, whereas 71% of physicians would consider ablation as first-line therapy in patients with symptomatic AF and left ventricular ejection fraction <35%. Only 14% of the respondents manage cardiovascular risk factors in patients referred for CA using a dedicated AF risk factor management programme. Radiofrequency CA is the preferred technology for first-time AF (56%), followed by cryo-balloon CA (40%). This EHRA survey demonstrated a considerable variation in the management of patients undergoing AF ablation in routine practice and deviations between guideline recommendations and clinical practice.

Sudden cardiac death while waiting: do we need the wearable cardioverter-defibrillator?

Sudden cardiac death (SCD) is the most frequent cause of cardiovascular death in industrialized nations. Patients with cardiomyopathy are at increased risk for SCD and may benefit from an implantable cardioverter-defibrillator (ICD). The risk of SCD is highest in the first months after myocardial infarction or first diagnosis of severe non-ischemic cardiomyopathy. On the other hand, left ventricular function may improve in a subset of patients to such an extent that an ICD might no longer be needed. To offer protection from a transient risk of SCD, the wearable cardioverter-defibrillator (WCD) is available. Results of the first randomized clinical trial investigating the role of the WCD after myocardial infarction were recently published. This review is intended to provide insight into data from the VEST trial, and to put these into perspective with studies and clinical experience. As a non-invasive, temporary therapy, the WCD may offer advantages over early ICD implantation. However, recent data demonstrate that patient compliance and education play a crucial role in this new concept of preventing SCD.

Transcriptomic and proteomic profiling of human diabetic heart disease

 

Studies in animal models demonstrated the capability of type 2 diabetes (T2D) to induce cardiac dysfunction in the absence of vascular disease. However, whether and how T2D also impairs structure and function in human hearts remains poorly understood. Here, we performed transcriptional and proteomic profiling of left ventricular samples of 8 subjects with T2D, preserved EF (63,5%) and no history of ischemic heart disease (= diabetic cardiomyopathy; DbCM), 7 subjects with T2D, reduced EF (26,9%) and ischemic heart disease (= diabetic heart failure; DbHF), and 15 non-diabetic individuals with normal EF (64,7%) serving as controls. Among 1168 proteins identified by LC-MS/MS, 146 proteins were differentially regulated in DbHF, but only 66 in DbCM. Pathway analysis revealed downregulation of energy metabolic proteins, but upregulation of proteins involved in oxidative stress and inflammatory response. In DbCM, pathways of structural remodeling, cardiomyocyte proliferation, and mechanotransduction were upregulated. Bulk RNA sequencing revealed 1795 differentially regulated genes in DbHF, and 527 in DbCM, with only 128 genes being commonly regulated. DbHF, but not DbCM, could be clearly discriminated from controls by hierarchical clustering. While inflammation/immunity were major regulated pathways in DbHF, extracellular matrix remodeling and cellular growth were the most regulated pathways in DbCM. Thus, the differential regulation of biological pathways in DbCM versus DbHF suggests the existence of two distinct disease entities rather than DbHF being an advanced disease stage of DbCM.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Austrian Diabetes Society

A personalized real-time virtual model of whole heart electrophysiology

Computer models capable of representing the intrinsic personal electrophysiology (EP) of the heart in silico are termed virtual heart technologies. When anatomy and EP are tailored to individual patients within the model, such technologies are promising clinical and industrial tools. Regardless of their vast potential, few virtual technologies simulating the entire organ-scale EP of all four-chambers of the heart have been reported and widespread clinical use is limited due to high computational costs and difficulty in validation. We thus report on the development of a novel virtual technology representing the electrophysiology of all four-chambers of the heart aiming to overcome these limitations. In our previous work, a model of ventricular EP embedded in a torso was constructed from clinical magnetic resonance image (MRI) data and personalized according to the measured 12 lead electrocardiogram (ECG) of a single subject under normal sinus rhythm. This model is then expanded upon to include whole heart EP and a detailed representation of the His-Purkinje system (HPS). To test the capacities of the personalized virtual heart technology to replicate standard clinical morphological ECG features under such conditions, bundle branch blocks within both the right and the left ventricles under two different conduction velocity settings are modeled alongside sinus rhythm. To ensure clinical viability, model generation was completely automated and simulations were performed using an efficient real-time cardiac EP simulator. Close correspondence between the measured and simulated 12 lead ECG was observed under normal sinus conditions and all simulated bundle branch blocks manifested relevant clinical morphological features.

Cardiac relapse of extranodal NK/T-cell lymphoma manifesting as incessant ventricular tachycardia: a case report

Background

Cardiac tumours are rare but affected patients may present with symptoms mimicking other cardiac diseases. The most frequent symptoms include heart failure, arrhythmias, or embolic phenomena.

Case summary

A 39-year-old man with a history of extranodal NK/T-cell lymphoma of the nasal type (ENKTL-NT) in clinical remission presented at our department with incessant ventricular tachycardia. The arrhythmia could only be controlled with a combination of intravenously administered beta-blockers, ajmaline, and amiodarone. Diagnostic workup excluded ischaemia, but imaging revealed a tumour located in the apex of the left ventricle. Endomyocardial biopsy confirmed the diagnosis of cardiac relapse of ENKTL-NT. Upon chemotherapy no further arrhythmias developed.

Discussion

Many malignancies can metastasize into the heart. Multimodal imaging including echocardiography, cardiac magnetic resonance imaging, and a positron-emission tomography computed tomography paved the way to the diagnosis that was finally established by endomyocardial biopsy. In the present case, a cardiac metastasis from an ENKTL-NT presented with incessant ventricular tachycardia.

Patient motivation and adherence to an on-demand app-based heart rate and rhythm monitoring for atrial fibrillation management: data from the TeleCheck-AF project

AIMS

The aim of this TeleCheck-AF sub-analysis was to evaluate motivation and adherence to on-demand heart rate/rhythm monitoring app in patients with atrial fibrillation (AF).

METHODS AND RESULTS

Patients were instructed to perform 60 s app-based heart rate/rhythm recordings 3 times daily and in case of symptoms for 7 consecutive days prior to teleconsultation. Motivation was defined as number of days in which the expected number of measurements (≥3/day) were performed per number of days over the entire prescription period. Adherence was defined as number of performed measurements per number of expected measurements over the entire prescription period.Data from 990 consecutive patients with diagnosed AF [median age 64 (57-71) years, 39% female] from 10 centres were analyzed. Patients with both optimal motivation (100%) and adherence (≥100%) constituted 28% of the study population and had a lower percentage of recordings in sinus rhythm [90 (53-100%) vs. 100 (64-100%), P < 0.001] compared with others. Older age and absence of diabetes were predictors of both optimal motivation and adherence [odds ratio (OR) 1.02, 95% coincidence interval (95% CI): 1.01-1.04, P < 0.001 and OR: 0.49, 95% CI: 0.28-0.86, P = 0.013, respectively]. Patients with 100% motivation also had ≥100% adherence. Independent predictors for optimal adherence alone were older age (OR: 1.02, 95% CI: 1.00-1.04, P = 0.014), female sex (OR: 1.70, 95% CI: 1.29-2.23, P < 0.001), previous AF ablation (OR: 1.35, 95% CI: 1.03-1.07, P = 0.028).

CONCLUSION

In the TeleCheck-AF project, more than one-fourth of patients had optimal motivation and adherence to app-based heart rate/rhythm monitoring. Older age and absence of diabetes were predictors of optimal motivation/adherence.

Early diagnosis and better rhythm management to improve outcomes in patients with atrial fibrillation: the 8th AFNET/EHRA consensus conference

Despite marked progress in the management of atrial fibrillation (AF), detecting AF remains difficult and AF-related complications cause unacceptable morbidity and mortality even on optimal current therapy. This document summarizes the key outcomes of the 8th AFNET/EHRA Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA). Eighty-three international experts met in Hamburg for 2 days in October 2021. Results of the interdisciplinary, hybrid discussions in breakout groups and the plenary based on recently published and unpublished observations are summarized in this consensus paper to support improved care for patients with AF by guiding prevention, individualized management, and research strategies. The main outcomes are (i) new evidence supports a simple, scalable, and pragmatic population-based AF screening pathway; (ii) rhythm management is evolving from therapy aimed at improving symptoms to an integrated domain in the prevention of AF-related outcomes, especially in patients with recently diagnosed AF; (iii) improved characterization of atrial cardiomyopathy may help to identify patients in need for therapy; (iv) standardized assessment of cognitive function in patients with AF could lead to improvement in patient outcomes; and (v) artificial intelligence (AI) can support all of the above aims, but requires advanced interdisciplinary knowledge and collaboration as well as a better medico-legal framework. Implementation of new evidence-based approaches to AF screening and rhythm management can improve outcomes in patients with AF. Additional benefits are possible with further efforts to identify and target atrial cardiomyopathy and cognitive impairment, which can be facilitated by AI.

PRospective REgistry of PAtients in REfractory cardiogenic shock-The PREPARE CardShock registry

Aim

Cardiogenic shock (CS) is a hemodynamically complex multisystem syndrome associated with persistently high morbidity and mortality. As CS is characterized by progressive failure to provide adequate systemic perfusion, supporting end‐organ perfusion using mechanical circulatory support (MCS) seems intriguing. Since most patients with CS present in the catheterization laboratory, percutaneously implantable systems have the widest adoption in the field. We evaluated feasibility, outcomes, and complications after the introduction of a full‐percutaneous program for both the Impella CP device and venoarterial extracorporeal membrane oxygenator (VA‐ECMO).

Methods

PREPARE CardShock (PRospective REgistry of PAtients in REfractory cardiogenic shock) is a prospective single‐center registry, including 248 consecutive patients between May 2019 and April 2021, who underwent cardiac catheterization and displayed advanced cardiogenic shock. The median age was 70 (58–77) years and 28% were female. Sixty‐five percent of the cases had cardiac arrest, of which 66% were out‐of‐hospital cardiac arrest. A local standard operating procedure (SOP) indicating indications as well as relative and absolute contraindications for different means of MCS (Impella CP or VA‐ECMO) was used to guide MCS use. The primary endpoint was in‐hospital death and secondary endpoints were spontaneous myocardial infarction and major bleedings during the hospital stay.

Results

Overall mortality was 50.4% with a median survival of 2 (0–6) days. Significant independent predictors of mortality were cardiac arrest during the index event (odds ratio [OR] with 95% confidence interval [CI]: 2.53 [1.43–4.51]; p = 0.001), age > 65 years (OR: 2.05 [1.03–4.09]; p = 0.036]), pH < 7.30 (OR: 2.69 [1.56–4.66]; p < 0.001), and lactate levels > 2 mmol/L (OR: 4.51 [2.37–8.65]; p < 0.001).

Conclusions

Conclusive SOPs assist target‐orientated MCS use in CS. This study provides guidance on the implementation, validation, and modification of newly established MCS programs to aid centers that are establishing such programs.

miR-1183 Is a Key Marker of Remodeling upon Stretch and Tachycardia in Human Myocardium

Many cardiac insults causing atrial remodeling are linked to either stretch or tachycardia, but a comparative characterization of their effects on early remodeling events in human myocardium is lacking. Here, we applied isometric stretch or sustained tachycardia at 2.5 Hz in human atrial trabeculae for 6 h followed by microarray gene expression profiling. Among largely independent expression patterns, we found a small common fraction with the microRNA miR-1183 as the highest up-regulated transcript (up to 4-fold). Both, acute stretch and tachycardia induced down-regulation of the predicted miR-1183 target genes ADAM20 and PLA2G7. Furthermore, miR-1183 was also significantly up-regulated in chronically remodeled atrial samples from patients with persistent atrial fibrillation (3-fold up-regulation versus sinus rhythm samples), and in ventricular myocardium from dilative cardiomyopathy hearts (2-fold up-regulation) as compared to non-failing controls. In sum, although stretch and tachycardia show distinct transcriptomic signatures in human atrial myocardium, both cardiac insults consistently regulate the expression of miR-1183 and its downstream targets in acute and chronic remodeling. Thus, elevated expression of miR-1183 might serve as a tissue biomarker for atrial remodeling and might be of potential functional significance in cardiac disease.

Fine-Tuning Cardiac Insulin-Like Growth Factor 1 Receptor Signaling to Promote Health and Longevity

BACKGROUND

The insulin-like growth factor 1 (IGF1) pathway is a key regulator of cellular metabolism and aging. Although its inhibition promotes longevity across species, the effect of attenuated IGF1 signaling on cardiac aging remains controversial.

METHODS

We performed a lifelong study to assess cardiac health and lifespan in 2 cardiomyocyte-specific transgenic mouse models with enhanced versus reduced IGF1 receptor (IGF1R) signaling. Male mice with human IGF1R overexpression or dominant negative phosphoinositide 3-kinase mutation were examined at different life stages by echocardiography, invasive hemodynamics, and treadmill coupled to indirect calorimetry. In vitro assays included cardiac histology, mitochondrial respiration, ATP synthesis, autophagic flux, and targeted metabolome profiling, and immunoblots of key IGF1R downstream targets in mouse and human explanted failing and nonfailing hearts, as well.

RESULTS

Young mice with increased IGF1R signaling exhibited superior cardiac function that progressively declined with aging in an accelerated fashion compared with wild-type animals, resulting in heart failure and a reduced lifespan. In contrast, mice with low cardiac IGF1R signaling exhibited inferior cardiac function early in life, but superior cardiac performance during aging, and increased maximum lifespan, as well. Mechanistically, the late-life detrimental effects of IGF1R activation correlated with suppressed autophagic flux and impaired oxidative phosphorylation in the heart. Low IGF1R activity consistently improved myocardial bioenergetics and function of the aging heart in an autophagy-dependent manner. In humans, failing hearts, but not those with compensated hypertrophy, displayed exaggerated IGF1R expression and signaling activity.

CONCLUSIONS

Our findings indicate that the relationship between IGF1R signaling and cardiac health is not linear, but rather biphasic. Hence, pharmacological inhibitors of the IGF1 pathway, albeit unsuitable for young individuals, might be worth considering in older adults.

Multi-national survey on the methods, efficacy, and safety on the post-approval clinical use of pulsed field ablation (MANIFEST-PF)

AIMS

Pulsed field ablation (PFA) is a novel atrial fibrillation (AF) ablation modality that has demonstrated preferential tissue ablation, including no oesophageal damage, in first-in-human clinical trials. In the MANIFEST-PF survey, we investigated the 'real world' performance of the only approved PFA catheter, including acute effectiveness and safety-in particular, rare oesophageal effects and other unforeseen PFA-related complications.

METHODS AND RESULTS

This retrospective survey included all 24 clinical centres using the pentaspline PFA catheter after regulatory approval. Institution-level data were obtained on patient characteristics, procedure parameters, acute efficacy, and adverse events. With an average of 73 patients treated per centre (range 7-291), full cohort included 1758 patients: mean age 61.6 years (range 19-92), female 34%, first-time ablation 94%, paroxysmal/persistent AF 58/35%. Most procedures employed deep sedation without intubation (82.1%), and 15.1% were discharged same day. Pulmonary vein isolation (PVI) was successful in 99.9% (range 98.9-100%). Procedure time was 65 min (38-215). There were no oesophageal complications or phrenic nerve injuries persisting past hospital discharge. Major complications (1.6%) were pericardial tamponade (0.97%) and stroke (0.4%); one stroke resulted in death (0.06%). Minor complications (3.9%) were primarily vascular (3.3%), but also included transient phrenic nerve paresis (0.46%), and TIA (0.11%). Rare complications included coronary artery spasm, haemoptysis, and dry cough persistent for 6 weeks (0.06% each).

CONCLUSION

In a large cohort of unselected patients, PFA was efficacious for PVI, and expressed a safety profile consistent with preferential tissue ablation. However, the frequency of 'generic' catheter complications (tamponade, stroke) underscores the need for improvement.

Single-center outcome after ablation of atrial fibrillation using very high-power short duration pulmonary vein isolation

Funding Acknowledgements

Type of funding sources: None.

Background

Catheter ablation of atrial fibrillation is (AF) an established second line therapy for patients with symptomatic paroxysmal (PAF) and persistent AF (persAF). Novel ablation catheters with integrated thermocouples allow fast application of radiofrequency lesions with powers up to 90W.

We aimed to describe primary and secondary outcomes after very high-power short duration (vHPSD) ablation.

Methods

126 consecutive patients (78 PAF, 43 persAF, 5 longstanding persistent AF) underwent pulmonary vein isolation (PVI) using the QDOT Micro Catheter (Biosense Webster) with the ablation mode QMODE+ (90W, 4s, interlesion distance ≤4mm anterior, ≤6mm posterior).

Results

Mean age was 62±9 years, 33% were female, median CHA2DS2-VASc Score was 2 (0, 7). Median follow up duration was 204 (14, 461) days. 30% of patients had additional ablation of typical right atrial flutter.

Primary success rate to achieve pulmonary vein isolation was achieved in all patients, no catheter-related complications (e.g., charring, steam pop) occurred. First pass isolation of all 4 PVs was achieved in 48% of patients, re-ablations were necessary in the carina regions (right: 37% of cases, left: 29%) and ridge (14%). Median procedure for PVI only were 102 (45-210) minutes.

Arrhythmia-free survival was 79,6% (see Figure 1). Eight patients underwent re-do procedures during follow-up showing most commonly showing gaps in the right inferior PV (63%) and ridge (50%).

Conclusion

Very high-power short duration ablation allows safe and quick pulmonary vein isolation. However, first pass isolation rate is low due to gaps in the carina regions. Arrhythmia-free survival is comparable to other pulmonary vein isolation techniques.

Figure 1: Left panel: Sample image of a vHPSD-PVI, posterior view of the left atrium. Right panel: Single procedure arrhythmia-free survival after vHPSD-PVI.

Photoplethysmography telemonitoring during the first week after atrial fibrillation ablation: Feasibility and clinical implications

Funding Acknowledgements

Type of funding sources: None.

The incidence of early atrial fibrillation (AF) recurrence within the first week after AF ablation and its predictive value for late AF recurrences are unclear. TeleCheck-AF is a remote on-demand mobile health (mHealth) infrastructure, which is based on a mobile phone app using photoplethysmography (PPG) technology (Fibricheck) allowing rate and rhythm monitoring through teleconsultations. The feasibility and clinical implications of PPG telemonitoring specifically during the first week after atrial fibrillation ablation is unknown.

Methods

Within the TeleCheck-AF project, the Medical University offered a total of 382 consecutive patients undergoing AF ablation (between June 1st 2020 and December 15th 2021) photoplethysmography (PPG) telemonitoring with "FibriCheck" during the first week after the ablation procedure. Patients received a QR code for activation of the software on their smartphone and were connected to the clinician’s telemedicine portal. They were instructed to perform rhythm monitoring three times per day and in case of symptoms. Clinicians assessed the tracings and contacted the patients if therapeutic steps were indicated.

Results

In total, 119 patients (31%) agreed to perform telemonitoring after ablation. Patients undergoing telemonitoring were younger compared to those who refused participation (58±10years vs. 62±10years, p&lt;0.001). 34% were female, median CHA2DS2-VASc-Score was 1 (0-6). 62% of patients had paroxysmal AF and 37% had persistent AF. One of four patients (24%) had already undergone previous ablations. Most index ablations were radiofrequency ablations (89%; 7% cryo; 4% pulsed field ablation). Median follow up duration was 281 (16-620) days.

27% of patients had tracings suggestive of AF in the week following the index ablation. Telemonitoring resulted in clinical interventions ins 24% of patients: amiodarone was started in 8%, class I antiarrhythmic drugs were up titrated in 7%, cardioversion was scheduled in 5%, antiarrhythmic drugs were reduced due to symptomatic bradycardia in 3% of patients.

During follow-up, 22% of patients had ECG-documented AF recurrences. PPG recordings suggestive of AF in the week after ablation were predictive of late recurrences (p&lt;0.001).

Conclusion

Rhythm monitoring with a PPG-based mHealth application was feasible and often resulted in clinical interventions. Due to its high availability, PPG-based follow-up actively involving patients after AF ablation may close a diagnostic and prognostic gap and increase active patient-involvement.

Figure 1: Schematic overview of the telemonitoring process. After the ablation, the patient measures PPGs for one week, dashboard view for clinician shows regular rhythm (green, atrial fibrillation (red) and unclear tracings (blue).

Electroanatomic mapping system guided his bundle pacemaker implantation: experience of the his bundle registry graz

Funding Acknowledgements

Type of funding sources: None.

Background

Patients with bradyarrhythmia in need for ventricular pacing may suffer from pacing-induced heart failure due to unphysiological right ventricular pacing. His bundle pacing (HBP) allows to overcome this common issue with a more physiologic approach but real-life procedural data using this technology is scarce.

Methods

We report a single centre experience of the first 44 consecutive patients being implanted with a His-bundle-based pacemaker 09/2020-11/2021 per 3D-mapping guided implantation due to different types of bradyarrhythmia, or for cardiac resynchronisation therapy in heart failure combined with a left-ventricular lead (HOT-CRT) ± a right ventricular defibrillator lead. The positioning of the His-bundle-lead was done by identifying the His-bundle-location with a 3D electroanatomic mapping system via an introducing sheath that is provided with electrodes at its tip.

Results

Mean age was 70 [16;86] years, 12/44 (27%) patients were female, mean baseline LVEF was 44±18%. Baseline ECG was captured: QRS width was 123±33ms, with typical LBBB in 14/44 (32%), typical RBBB in 4/44 (9%), alternating BBB in one patient (2%) and either no BBB or ventricular escape rhythm in 25/44 (57%). Indications for implantation were AV-block grade II-III in 19/44 (43%), primary prophylactic ICD indication in HFrEF in 13/44 (30%), atrial fibrillation with bradycardic conduction in 7/44 patients (16%), sick-sinus-syndrome in 4/44 (9%) and secondary prophylactic ICD indication in one patient (2%). In 41/44 (93%) a primary device was implanted, in 3/44 (7%) a pre-existent device was upgraded with a HB lead.

Therefore, 14 dual-chamber-pacemaker, 5 single-chamber-pacemaker, 8 single-chamber CRT-P, 11 dual-chamber CRT-P, 4 single-chamber CRT-D, 2 dual-chamber CRT-D were implanted. In 50 patients HBP was attempted, while in 6/50 (12%) patients outside of this analysis the attempt was not successful, these patients were consecutively implanted with a non-HBP-device and therefor excluded from the further analysis.

In the 44 patients included in this analysis with primary successful HBP, 4/44 (9%) his-bundle-leads dislocated within the first 48 hours, leading to a secondary success rate of 91%. There were two post-procedural pneumothorax that needed drainage, no major procedure-related complications occurred. Median skin-to skin procedure time was 109±50 minutes. The paced QRS width at the post-implantation follow up was 115±32ms with a change in QRS width of -10ms (+72;-92ms). When excluding the secondary lead dislocations and including only the successful HB paced QRS complexes, the paced QRS width was 105±30ms and the change in QRS width was -12±42ms. The mean his-bundle threshold was 1,2±1V over 0,5ms (0,5;1,5ms). The proportion of ventricular pacing was 69±38%.

Conclusion

Electroanatomic-guided His bundle pacing is feasible, with high implantation success rate and electric impact, both regarding QRS width and pacing threshold.

Prevention of early sudden cardiac death after myocardial infarction using the wearable cardioverter defibrillator - results from a real-life cohort

Funding Acknowledgements

Type of funding sources: None.

Background

Patients are at elevated risk of sudden cardiac death (SCD) after acute myocardial infarction (MI). The VEST trial failed to show a significant reduction in arrhythmic mortality in patients prescribed with a wearable converter-defibrillator (WCD), having a lower than expected wearing compliance. We aimed to investigate the incidence of WCD treatments and outcomes of all patients with acute MI and LVEF ≤35% in a real life and well-compliant cohort in Austria.

Methods

We performed a retrospective analysis of all patients meeting the in- and exclusion criteria of the original VEST trial within the Austrian WCD registry between 2010 and 2021.

Results

105/896 patients (12%) with an average age of 64±11 years (12% female; LVEF 28±6%) registered in the Austrian WCD registry met the VEST in- and exclusion criteria. 104/105 patients were revascularized and prescribed with a WCD prescription for 69 (1;277) days, the median wearing duration was 23.5 (0;24) hours/day. 4/105 (3.8%) patients received 9 appropriate WCD shocks, the per patient shock rate was 2 (1;5). No inappropriate shock was delivered. During follow-up, 46/105 patients (44%) received an ICD after the WCD period, 4/105 (3.8%) patients died during follow-up. Arrhythmic mortality (1.9% Austria vs. 1.6% VEST, p=ns), as well as all-cause mortality (3.8% vs. 3.1%, p=ns) in the Austrian cohort were comparable to the VEST cohort.

Conclusion

The WCD is a safe treatment option in a highly selected cohort of patients with a LVEF ≤35% after acute myocardial infarction. However, despite excellent WCD compliance as opposed to the VEST study, only 3.8% of patients receive appropriate WCD shocks and the arrhythmic mortality rate was not significantly improved.

Graded lower body negative pressure induces intraventricular negative pressures and incremental diastolic suction: a pressure volume study in a porcine model

Lower body negative pressure (LBNP) has been a tool to study compensatory mechanisms to central hypovolemia for decades. However, underlying hemodynamic mechanisms were mostly assessed non-invasively and remain unclear. We hypothesized that incremental LBNP reduces diastolic filling and thereby affects left ventricular (LV) diastolic suction (DS). Here, we investigated the impact of graded LBNP at 3 different levels of seal as well as during beta-adrenergic stimulation by invasive pressure-volume (PV) analysis. Eight Landrace pigs were instrumented closed-chest for PV assessment. LBNP was applied at three consecutive locations: I) cranial, 10cm below xiphoid process; II) medial, half-way between cranial and caudal; III) caudal, at the iliac spine. Level III) was repeated under dobutamine infusion. At each level, baseline measurements were followed by application of incremental LBNP of -15, -30 and -45 mmHg. LBNP induced varying degrees of preload-dependent hemodynamic changes, with cranial LBNP inducing more pronounced effects than caudal. According to the Frank-Starling mechanism, graded LBNP progressively reduced LV stroke volume (LV SV) following a decrease in LV end-diastolic volume. Negative intraventricular minimal pressures were observed during dobutamine-infusion as well as higher levels of LBNP. Of note, incremental LV negative pressures were accompanied by increasing DS volumes, derived by extrapolating the volume at zero transmural pressure, the so-called equilibrium volume (V0), related to LV SV. In conclusion, graded preload reduction shifts the PV loop to smaller volumes and end-systolic volume below V0, which induces negative LV pressures and increases LV suction. Accordingly, LBNP induced central hypovolemia is associated with increased DS.