Malcolm Finlay

EP Europace·Potter et al.·Guideline

Vascular access and closure management for electrophysiological interventions in 2025: a Clinical Consensus Statement of the European Heart Rhythm Association and the European Association of Percutaneous Cardiovascular Interventions of the ESC, and the ESC Working Group on Cardiovascular Surgery

Adopt these standardized vascular access protocols in EP procedures to reduce complications; extends prior expert opinion into unified clinical and research guidance.

European Heart Journal - Quality of Care and Clinical Outcomes·Dulal et al.·Original Research

Catheter Ablation in Patients with Atrial Fibrillation and Hypertrophic Obstructive Cardiomyopathy: A Real-World Comparative Outcomes Study

Observational analysis found catheter ablation reduced mortality and ischemic stroke in patients with atrial fibrillation and hypertrophic obstructive cardiomyopathy.

Heart Rhythm·Kanthasamy et al.·cohort

Ambulatory AF ablation shows safety with a 1.2% acute adverse event rate and no major complications.

Supports ambulatory AF ablation in selected patients; hypothesis-generating and requires prospective validation before broader adoption.

Heart Rhythm·Kanthasamy et al.·cohort

AF-PROMs questionnaire demonstrates excellent internal consistency, strong test-retest reliability, and responsiveness to clinical changes.

AF-PROMs supports reliable QoL assessment in AF; leaves open routine adoption pending prospective validation.

JACC. Clinical electrophysiology·Kanthasamy et al.·cohort

Subclavian ansae stimulation elicits a positive hemodynamic response in ~65% of paroxysmal AF patients.

Percutaneous subclavian ansae stimulation in humans successfully modulates cardiac autonomic tone, demonstrating significant acute hemodynamic and electrophysiological effects.

Nature Cardiovascular Research·Vyas et al.·Original Research

Tissue-resident memory T cells in epicardial adipose tissue comprise transcriptionally distinct subsets that are modulated in atrial fibrillation

EP Europace·Creta et al.·Original Research

Near-zero fluoroscopy technique for cardiac electronic device implantation: long-term outcomes

Introduction Radiation hazards are a major concern for both patients and staff. We have previously described a near-zero fluoroscopy technique for cardiac electronic device implantation. In this study, we aimed to investigate the long-term safety of this technique and compare outcomes and procedural metrics with a conventional approach in a larger population. Methods Low-dose fluoroscopy technique. Radiation exposure during fluoroscopy is directly proportional to the time the unit is activated. Typically, the pedal switch is depressed for at least a few seconds per imaging sequence in order to visualize "live" movements of either the leads during their positioning or the needle during a fluoroscopy-guided puncture of the subclavian vein. Our technique consists of setting a low frame rate per second (0.5-3.75fps) and momentarily triggering the foot pedal switch only to obtain screenshots of the position of the leads/needle. Use of live electrograms to assist spatial awareness of lead position (e.g. Atrial, Coronary Sinus, Ventricular signals) acts as an adjunct to guidance. Study design We included consecutive patients undergoing permanent pacemaker (PPM) or cardiac defibrillator (ICD) implant at our center from July 2018 to December 2022 using the near-zero fluoroscopy technique. Procedures were performed by three operators (AC, MD, MF). Cumulative radiation dose was measured using dose-area product (DAP). We assessed procedure success and complication rate during long-term follow-up. We compared the procedural metrics and outcomes with a cohort of patients with PPM or ICD implanted in our centre by senior operators, using a traditional fluoroscopic approach. Propensity score was adopted to match baseline characteristics between the study and control group. Results The total population consisted of 412 patients (74.2±13.9 years, 60.9% male). We included 206 who underwent PPM or ICD implantation using the low-dose fluoroscopy technique, and 206 matched-control. A PPM or ICD was successfully implanted in all patients. Fluoroscopy time and DAP were significantly lower in the low-dose fluoroscopy group, mean 2.3±2.0 seconds versus 258.4±252.1 seconds (P<0.001) and 3.4±3.5 µGym2 versus 29.8±55.4 µGym2 (P<0.001), respectively. Mean procedure time was 49.0±20.8 minutes in the low fluoroscopy group and 65.7±26.8 minutes in the control group (P<0.001). Median frame per second setting was 0.5 in the low-dose cohort. After a mean follow-up of 441±470 days, the rate of complications was identical across groups (2.4%, p = 1.0). Conclusion This near-zero dose fluoroscopy technique is effective and safe, enabling a 10x reduction in radiation exposure during device implant. Modification of traditional implant and imaging techniques can provide material reductions in fluoroscopy dose to even below that for a standard PA chest radiograph.

EP Europace·Kanthasamy et al.·Original Research

The influence of subclavian ansae stimulation on cardiac hemodynamics and electrophysiology in atrial fibrillation- exploring a novel target for neuromodulation in atrial fibrillation (SAS-AF study)

Background Sympathetic nervous system activation plays a significant role in arrhythmia development and maintenance.Neuromodulation techniques such as stellate ganglion block and sympathectomy, are limited by off-target side effects and complex targeting.The Subclavian Ansae (SA,a nerve cord encircling the subclavian artery) may be an intravascular site allowing specific targeting of the cardiac afferent sympathetic system.Preclinical studies have revealed increased sympathetic tone upon selective SA stimulation. Objective We sought to define for the first time in Humans the functional anatomy and physiology of Subclavian Ansae via a percutaneous approach. Methods A prior cadaveric study defined the anatomical course of the subclavian ansae, encircling the subclavian arteries and connecting the middle cervical ganglia to inferior cervical ganglia/stellate.Patients undergoing catheter ablation for paroxysmal atrial fibrillation(pAF) under general anesthesia were prospectively recruited for the study. Subclavian Ansae stimulation (SAS) was performed on the left and/or the right (L/SAS ± R/SAS) within the subclavian artery using the TactiCath Ablation Catheter introduced via a femoral arterial sheath. Stimulation parameters included up to 70 V output, 10 Hz frequency, and pulse width of 2-4ms for 20-30s. Test pulses ensured no cardiac capture during stimulation. Participants discontinued antiarrhythmic agents at least 4-5 half-lives prior to the procedure. Invasive arterial blood pressure(BP), heart rate (HR), and electrophysiological parameters were recorded in response to selective stimulation. An increase of ten percent or more in either arterial blood pressure(BP) or heart rate(HR) from the initial baseline measurements was deemed a positive response. Results 15 patients (62±11 years, 9 males, pAF duration 51±24 months) underwent the simulation protocol prior to their clinical AF ablation procedure. A positive hemodynamic response was observed in nine patients, and among them, arrhythmia was inducible in 3 patients (atrial fibrillation in 2 patients and repeated runs of atrial ectopy in 1 patient) in response to SAS. Mean sinus cycle length(CL) decreased(chronotropic) after stimulation,particularly with a significant change observed in response to R/SAS. Additionally,L/SAS led to a notable increase in mean systolic (SBP) and diastolic(DBP) blood pressure (inotropic). While the mean right atrial effective refractory period (ERP) did not significantly decrease after stimulation, there was a demonstrable difference in interatrial conduction time(dromotropy). Six patients, including the initial 3 subjected to low-energy stimulation (up to 12V), did not exhibit an adrenergic response. Conclusion This study represents the first successful application of selective SAS in humans. A heterogeneity in electrophysiological modulation by SAS exists, including laterality.The SA is a potential important target for targeted autonomic neuromodulation therapy

EP Europace·Kanthasamy et al.·Original Research

Objective randomised blinded investigation of therapeutic ablation versus cardioversion for persistent atrial fibrillation- outcomes of the feasibility

Background Patients with persistent atrial fibrillation (pers.AF) commonly undergo catheter ablation (CA) for symptom relief and improved quality of life(QoL). However,the benefits of CA compared to DC cardioversion (DCCV) or medical therapy lack substantial evidence from blinded randomized trials. Purpose Conducting such a large-scale trial presents substantial challenges in terms of recruitment, maintaining blinding, and implementation.To address this, we conducted a pilot study prior to a definitive larger study. Methods This feasibility trial is a single-centre, prospective, randomised, double-blinded placebo control study. Patients with early pers AF (<2 years) eligible for pulmonary vein isolation (PVI) or DCCV were enrolled. Twenty patients were recruited, accounting for 10% of the proposed larger trial based on power calculation. The intervention arm (PVI + DCCV) and placebo arm (Placebo + DCCV) were randomised in a 1:1 manner after ultrasound-guided vascular access with local anaesthetic and deep sedation (Midazolam + opioid). All procedures were performed as day cases on uninterrupted oral anticoagulation. Phrenic nerve pacing was performed in the Placebo group, mimicking lab interactions and fluoroscopy system movements. Implantable loop monitors were inserted immediately after heparin reversal and groin sheath removal. A 6-week(wk) blanking period was observed post-procedure. Blinding was assessed using Bang's blinding index (BI) for both patients and medical staff and a successful blinding is considered BI between -0.2 to 0.2. Health-related quality of life (HRQoL) was evaluated using SF12, EQ5D-5L, and AF PROMS. The study obtained ethical approval (REC ref 19/LO/0775),adhered to the principles of the Declaration of Helsinki,and obtained written informed consent from all participants. Results A remarkable 92% of patients approached, expressed a willingness to participate in the study. Procedure time and time to discharge were similar between groups. The study successfully achieved blinding among the patients at day0 (BI = PVI-0.2 vs placebo- 0) and was maintained throughout the 6-wk and 3M follow-up, among the patients as well as clinical staff. HRQoL improved in the active group in terms of AF PROMS [Improved difference from baseline PVI 23 (±22); vs Placebo 2 (±10), p=<0.001 and SF-12 mental component (MCS) at 12M (PVI 11.8 (±11) vs placebo 8.54(±11.5), p= 0.017). Over a follow up period of 12M, there was a trend towards greater recurrence (60% vs 30%; p=0.07) and repeat procedures (70% vs 40%; p=0.4) in the placebo group. Conclusion: Performing a blinded placebo-controlled interventional study to assess the efficacy of PVI is feasible and high recruitment rates are achievable. CA appears to result in better arrhythmic and QoL outcomes;a full-scale follow-on study will assess the true efficacy of CA in patients with early pers.AF and allow consideration of whether there is a role for DCCV in many patients.

Circulation Arrhythmia and Electrophysiology·Maclean et al.·cohort

The BLISTER score demonstrated superior discriminative performance compared to the PADIT score for predicting cardiac implantable electronic device infection.

May inform CIED infection risk stratification; leaves open prospective validation and outcome impact.

EP Europace·Honarbakhsh et al.·cohort

Successful PVI was achieved in 99.3% of patients, with 97.2% performed as day cases and a complication rate of <1%; safety and efficacy were comparable between PolarX and AFA cohorts.

Same-day discharge after PolarX PVI appears feasible; leaves open the need for randomized trials to confirm safety versus AFA.

Heart Rhythm O2·Dhillon et al.·cohort

ECGI-guided ablation linked to ~46% arrhythmia freedom off drugs at one year in recurrent post-PVI AF.

May support ECGI-guided driver ablation in recurrent persistent AF post-PVI; leaves open efficacy in randomized trials.

Circulation Arrhythmia and Electrophysiology·Specterman et al.·preclinical

Kir6.2 global knockout prevents hypoxia-induced atrial arrhythmogenicity and wavefront path length shortening in murine models.

KATP blockade should not yet inform clinical AF management; leaves open translation of murine hypoxia findings to human arrhythmias.

Frontiers in Cardiovascular Medicine·Creta et al.·cohort

An amplified P-wave duration ≥ 150 ms independently predicted a higher risk of arrhythmia recurrence following cryoballoon pulmonary vein isolation in patients with non-paroxysmal AF.

Amplified P-wave duration ≥150 ms is an independent predictor of arrhythmia recurrence after cryoballoon pulmonary vein isolation, identifying patients with significant atrial cardiomyopathy who may benefit from additional ablation strategies.

Journal of Cardiovascular Electrophysiology·Kanthasamy et al.·cohort

Catheter ablation of atrial fibrillation using the Heliostar RF balloon achieved successful isolation of all pulmonary veins with a low complication rate and no mortality at 30 days.

Heliostar balloon PVI appears feasible with short times; hypothesis-generating pending randomized comparisons to established catheters.

Journal of Cardiovascular Electrophysiology·Honarbakhsh et al.·cohort

Coronary sinus cycle length variability <30 ms strongly predicted freedom from atrial fibrillation or atrial tachycardia recurrence during long-term follow-up.

Hypothesis-generating for CS electrogram-guided ablation in persistent AF; prospective trials needed before clinical adoption.

EP Europace·Honarbakhsh et al.·cohort

The PolarX Cryoballoon showed comparable efficacy to the AFA Cryoballoon for atrial fibrillation ablation, with time to reach -40°C predicting initial pulmonary vein isolation.

Comparable efficacy observed with PolarX versus AFA cryoballoon in this cohort; hypothesis-generating for temperature metrics pending randomized trials.

Science·Reynolds et al.·Original Research

Immune boosting by B.1.1.529 ( Omicron) depends on previous SARS-CoV-2 exposure

The Omicron, or Pango lineage B.1.1.529, variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carries multiple spike mutations with high transmissibility and partial neutralizing antibody (nAb) escape. Vaccinated individuals show protection against severe disease, often attributed to primed cellular immunity. We investigated T and B cell immunity against B.1.1.529 in triple BioNTech BNT162b2 messenger RNA-vaccinated health care workers (HCWs) with different SARS-CoV-2 infection histories. B and T cell immunity against previous variants of concern was enhanced in triple-vaccinated individuals, but the magnitude of T and B cell responses against B.1.1.529 spike protein was reduced. Immune imprinting by infection with the earlier B.1.1.7 (Alpha) variant resulted in less durable binding antibody against B.1.1.529. Previously infection-naïve HCWs who became infected during the B.1.1.529 wave showed enhanced immunity against earlier variants but reduced nAb potency and T cell responses against B.1.1.529 itself. Previous Wuhan Hu-1 infection abrogated T cell recognition and any enhanced cross-reactive neutralizing immunity on infection with B.1.1.529.

Journal of Cardiovascular Electrophysiology·Maclean et al.·cohort

Use of a transseptal guidewire reduced the risk of TSP-related cardiac tamponade, as did top quartile operator experience and TOE guidance, whereas failure to cross first pass increased risk.

Transseptal guidewire and TOE may lower tamponade risk in left atrial ablation; extends observational data but leaves open need for RCTs.