Improved procedural workflow for catheter ablation of paroxysmal AF with high-density mapping system and advanced technology: Rationale and study design of a multicenter international study

The antral region of pulmonary veins (PV)s seems to play a key role in a strategy aimed at preventing atrial fibrillation (AF) recurrence. Particularly, low-voltage activity in tissue such as the PV antra and residual potential within the antral scar likely represent vulnerabilities in antral lesion sets, and ablation of these targets seems to improve freedom from AF. The aim of this study is to validate a structured application of an approach that includes the complete abolition of any antral potential achieving electrical quiescence in antral regions.The improveD procEdural workfLow for cathETEr ablation of paroxysmal AF with high density mapping system and advanced technology (DELETE AF) study is a prospective, single-arm, international post-market cohort study designed to demonstrate a low rate of clinical atrial arrhythmias recurrence with an improved procedural workflow for catheter ablation of paroxysmal AF, using the most advanced point-by-point RF ablation technology in a multicenter setting. About 300 consecutive patients with standard indications for AF ablation will be enrolled in this study. Post-ablation, all patients will be monitored with ambulatory event monitoring, starting within 30 days post-ablation to proactively detect and manage any recurrences within the 90-day blanking period, as well as Holter monitoring at 3, 6, 9, and 12 months post-ablation. Healthcare resource utilization, clinical data, complications, patients' medical complaints related to the ablation procedure and patient's reported outcome measures will be prospectively traced and evaluated.The DELETE AF trial will provide additional knowledge on long-term outcome following a structured ablation workflow, with high density mapping, advanced algorithms and local impedance technology, in an international multicentric fashion. DELETE AF is registered at ClinicalTrials.gov (NCT05005143).© 2022 The Authors. Clinical Cardiology published by Wiley Periodicals LLC

A new mapping method with the Rhythmia™ navigation system reduces radiation exposure. Preliminary experience in SVT procedures

Purpose: Electrophysiological studies and ablation procedures expose both physicians and patients to a significant amount of radiation. Most 3-D mapping systems provide improved tracking of catheters and enable radiation exposure to be reduced or even eliminated. However, there are no data on the ability of the Rhythmia ™ mapping system (Boston Scientific) to minimize fluoroscopy time and dose. Methods: Here, we report on the feasibility and safety of a novel non-fluoroscopic approach (NFA) that uses the Rhythmia ™ mapping system and a novel navigation-enabled ablation catheter in SVT and atrial flutter procedures, and describe in detail our modified procedural work-flow. A total of 20 consecutive patients who were referred to our center for RF ablation of SVT arrhythmias were included in this analysis to test our procedural work flow. Results: In our preliminary experience of the NFA work-flow, fluoroscopy times and radiological exposure were significantly reduced in comparison with the conventional approach. Conclusion: In our preliminary experience, arrhythmia ablation through a near-zero fluoroscopy approach involving the use of a novel ablation technology and the Rhythmia™ mapping system proved to be safe, feasible and effective in common atrial arrhythmias

High density mapping of aortic cusps improves near field detection of pre-potentials during premature ventricular contractions

Recognition of pre-potentials during activation mapping of aortic cusp premature ventricular contractions is useful to localize the precise site of origin and is an indicator of successful ablation, but sometimes these electrograms can be blunt and have low amplitude. High resolution mapping in the aortic cusp region allows improved near field detection of these signals in very few beats

Outcome of a Modified Sympathicotomy for Cardiac Neuromodulation of Untreatable Ventricular Tachycardia

Objectives: This study aimed to describe the preliminary results of a modified sympathicotomy for cardiac sympathetic denervation (CSD), which may reduce the predictive risk and intraoperative surgical time of the procedure. Background: CSD, in patients with refractory ventricular tachycardia (VT), is comprehensively recognized as an important treatment option for patients with structural heart disease as well as congenital inherited arrhythmia syndrome. Methods: We consecutively enrolled 5 patients with refractory VT. Baseline demographic, medical, and surgical data as well as arrhythmia outcomes and procedural complications were evaluated. Results: A total of 5 patients (mean age: 67.4 years) were enrolled for the treatment of refractory VT with a modified CSD technique. In 3 of 5 patients, an overall reduction in VT burden (ranging from 75% to 100%) and VT number was observed after the CSD despite an in-hospital early recurrence. Conclusions: A modified CSD (sympathicotomy T2–T5) with stellate ganglion sparing and the use of unipolar radiofrequency is feasible, effective, and safe in the setting of untreatable VT

Occlusion tool software for pulmonary vein occlusion verification in atrial fibrillation cryoballoon ablation

Background: Optimal pulmonary vein (PV) occlusion, usually verified with selective contrast injection, is mandatory to obtain an effective PV isolation during cryoballoon (CB) ablation. Aim of the study: The purpose of this study was to verify the feasibility and the accuracy of a new dielectric sensing system in assessing PV occlusion during CB ablation in patients with atrial fibrillation (AF). Methods: We enrolled 28 consecutive patients with paroxysmal or persistent AF. After transseptal access, a detailed image reconstruction of left atrium and PVs was achieved with an octapolar or decapolar mapping catheter (Achieve catheter, Medtronic Inc.) and KODEX-EPD system (EPD Solutions, a Philips company). The degree of PV occlusion with the inflated Arctic Front Advance Cryoballoon (Medtronic Inc.) was verified using the new “occlusion tool” software module (EPD Solutions, a Philips company) and compared to an angiogram obtained with contrast medium injection in each PV. Results: A total of 105 PV CB occlusion were tested. The new occlusion tool software module showed a 91% sensitivity and 76% specificity in assessing a complete PV occlusion verified with contrast medium injection. The positive predictive value was 80%, and the negative predictive value was 88.6%. Mean procedure time was 81 ± 17 minutes. Mean fluoroscopy time was 6 ± 2 minutes. No 30-day complications were observed. Conclusion: The new dielectric imaging system was able to assess the degree of PV occlusion during a CB ablation with good sensitivity and specificity

Increased temporal dispersion of myocardial repolarization in myotonic dystrophy Type 1 Beyond the cardiac conduction system

Background and objectives: The most frequently mechanism underlying sudden cardiac death in myotonic dystrophy type 1 (DM1) is bradyarrhythmias due to cardiac conduction abnormalities. However the risk of ventricular tachyarrhythmias remains a concern in clinical management as well as in its determinant. We therefore assessed autonomic nervous system activity aiming to disclose differences in the QT variability index (QTVI)-a marker of temporal myocardial repolarization lability-between DM1 patients and healthy controls. We also investigated the possible differences within DM1 patients by subdividing them according either to the presence of first degree atrioventricular block (1st AVB) or to the cytosine-thymine-guanine (CTG) repeat expansion size. Methods: Sixty-two DM1 patients and 20 healthy subjects underwent neurological and cardiological examinations, the latter including ECG, echocardiography and 24-hour Holter monitoring. All underwent a 5-minute ECG recording to assess heart rate variability power spectral components, and the QTVI values. Results: Power spectral data, namely total power, low frequency power and high frequency power, were lower, whereas QTVI values were higher in DM1 patients than in controls (p<.0001). Higher QTVI values were found in DM1 subgroups with 1st AVB (p=.009) and more than 500 CTG repeat (p=.014) with respect to DM1 patients without 1st AVB and CTG<500. Spectral data did not significantly differ. At multivariable analysis, QTVI and age were independently associated with PR interval and CTG repeat. Conclusions: The increased values of QTVI argue in favour of an important heart involvement extending beyond the conduction system. Whether QTVI could be useful in predicting clinical course of DM1 clearly requires larger prospective studies. (C) 2010 Elsevier Ireland Ltd. All rights reserved