Predicting and Recognizing Drug-Induced Type I Brugada Pattern Using ECG-Based Deep Learning.

BACKGROUND: Brugada syndrome (BrS) has been associated with sudden cardiac death in otherwise healthy subjects, and drug-induced BrS accounts for 55% to 70% of all patients with BrS. This study aims to develop a deep convolutional neural network and evaluate its performance in recognizing and predicting BrS diagnosis. METHODS AND RESULTS: Consecutive patients who underwent ajmaline testing for BrS following a standardized protocol were included. ECG tracings from baseline and during ajmaline were transformed using wavelet analysis and a deep convolutional neural network was separately trained to (1) recognize and (2) predict BrS type I pattern. The resultant networks are referred to as BrS-Net. A total of 1188 patients were included, of which 361 (30.3%) patients developed BrS type I pattern during ajmaline infusion. When trained and evaluated on ECG tracings during ajmaline, BrS-Net recognized a BrS type I pattern with an AUC-ROC of 0.945 (0.921-0.969) and an AUC-PR of 0.892 (0.815-0.939). When trained and evaluated on ECG tracings at baseline, BrS-Net predicted a BrS type I pattern during ajmaline with an AUC-ROC of 0.805 (0.845-0.736) and an AUC-PR of 0.605 (0.460-0.664). CONCLUSIONS: BrS-Net, a deep convolutional neural network, can identify BrS type I pattern with high performance. BrS-Net can predict from baseline ECG the development of a BrS type I pattern after ajmaline with good performance in an unselected population.

Anti-Arrhythmic Effects of Heart Failure Guideline-Directed Medical Therapy and Their Role in the Prevention of Sudden Cardiac Death: From Beta-Blockers to Sodium-Glucose Cotransporter 2 Inhibitors and Beyond.

Sudden cardiac death (SCD) accounts for a substantial proportion of mortality in heart failure with reduced ejection fraction (HFrEF), frequently triggered by ventricular arrhythmias (VA). This review aims to analyze the pathophysiological mechanisms underlying VA and SCD in HFrEF and evaluate the effectiveness of guideline-directed medical therapy (GDMT) in reducing SCD. Beta-blockers, angiotensin receptor-neprilysin inhibitors, and mineralocorticoid receptor antagonists have shown significant efficacy in reducing SCD risk. While angiotensin-converting enzyme inhibitors and angiotensin receptor blockers exert beneficial impacts on the renin-angiotensin-aldosterone system, their direct role in SCD prevention remains less clear. Emerging treatments like sodium-glucose cotransporter 2 inhibitors show promise but necessitate further research for conclusive evidence. The favorable outcomes of those molecules on VA are notably attributable to sympathetic nervous system modulation, structural remodeling attenuation, and ion channel stabilization. A multidimensional pharmacological approach targeting those pathophysiological mechanisms offers a complete and synergy approach to reducing SCD risk, thereby highlighting the importance of optimizing GDMT for HFrEF. The current landscape of HFrEF pharmacotherapy is evolving, with ongoing research needed to clarify the full extent of the anti-arrhythmic benefits offered by both existing and new treatments.

SCN5A gene variants and arrhythmic risk in Brugada syndrome: An updated systematic review and meta-analysis.

BACKGROUND: A rare gene variant in SCN5A can be found in approximately 20%-25% of patients with Brugada syndrome (BrS). OBJECTIVE: The aim of this systematic review and meta-analysis was to evaluate the differences in clinical characteristics of BrS patients with and without SCN5A rare variants and the prognostic role of SCN5A for ventricular arrhythmias in BrS. METHODS: PubMed and Cochrane Central Register of Controlled Trials (CENTRAL) were systematically searched from inception to January 2024 to identify all relevant studies. Studies were analyzed if they included patients diagnosed with BrS in whom genetic testing for SCN5A variants was performed and arrhythmic outcomes were reported. RESULTS: A total of 17 studies with 3568 BrS patients, of whom 3030 underwent genetic testing for SCN5A variants, fulfilled the eligibility criteria and were included. Compared with SCN5A- patients, SCN5A+ BrS patients more frequently had spontaneous type 1 electrocardiogram, history of syncope, and documented arrhythmias. Furthermore, higher PQ and QRS intervals in SCN5A+ BrS patients compared with SCN5A- have been found. The pooled analysis demonstrated a significant association between the presence of SCN5A rare variants in BrS patients and the risk of major arrhythmic events, with a pooled odds ratio of 2.14 (95% confidence interval, 1.53-2.99; I2 = 29%). CONCLUSION: SCN5A+ BrS patients showed a worse clinical phenotype compared with SCN5A-. The pooled analysis demonstrated a significant association between SCN5A+ mutation status and the risk of major arrhythmic events in BrS patients.

Pericarditis prophylactic therapy after sinus node-sparing hybrid ablation for inappropriate sinus tachycardia/postural orthostatic sinus tachycardia.

Background: Pericarditis is the most common complication following hybrid sinus node-sparing ablation for inappropriate sinus tachycardia (IST)/postural orthostatic tachycardia syndrome (POTS). Objective: The study sought to evaluate the association of prophylaxis therapy on the risk of symptomatic pericarditis following hybrid IST/POTS ablation. Methods: All consecutive patients undergoing to hybrid ablation of symptomatic IST/POTS refractory or intolerant to drugs were retrospectively analyzed. Pharmacological prophylaxis therapy was based on acetylsalicylic acid and colchicine started on the day of the ablation and continued for at least 3 months. The primary endpoint was occurrence of symptomatic pericarditis. The secondary endpoint was occurrence of pericarditis-related complications, including the following: duration of pericarditis >3 months, hospitalization for pericarditis, postpericardiectomy pleuro-pericarditis, and pericardiectomy. Results: A total of 220 patients undergone to hybrid IST/POTS ablation were included and 44 (20%) underwent prophylaxis therapy. Pericarditis occurred in 101 (45.9%) patients, with 97 (96%) in the first 5 days. At survival analysis, prophylaxis was associated with higher rate of freedom from pericarditis (81.9% vs 47.2%, log-rank P < .001). Pericarditis-related complications were low, occurring in 7 (3.2%) patients. There was no difference in pericarditis-related complications between the patients who underwent prophylaxis therapy and patients who did not. At Cox multivariate analysis, predictors of pericarditis were IST (vs POTS) (hazard ratio 0.61, 95% confidence interval0.39-0.99, P = .04) and prophylaxis therapy (hazard ratio 0.27, 95% confidence interval 0.13-0.55, P < .001). Conclusion: In a large cohort of patients undergoing hybrid ablation for IST/POTS, a prophylaxis therapy with acetylsalicylic acid and colchicine was associated with a lower rate of symptomatic pericarditis.

Genetic Testing in Brugada Syndrome: A 30-Year Experience.

BACKGROUND: A pathogenic/likely pathogenic variant can be found in 20% to 25% of patients with Brugada syndrome (BrS) and a pathogenic/likely pathogenic variant in SCN5A is associated with a worse prognosis. The aim of this study is to define the diagnostic yield of a large gene panel with American College of Medical Genetics and Genomics variant classification and to assess prognosis of SCN5A and non-SCN5A variants. METHODS: All patients with BrS, were prospectively enrolled in the Universitair Ziekenhuis Brussel registry between 1992 and 2022. Inclusion criteria for the study were (1) BrS diagnosis; (2) genetic analysis performed with a large gene panel; (3) classification of variants following American College of Medical Genetics and Genomics guidelines. Patients with a pathogenic/likely pathogenic variant in SCN5A were defined as SCN5A+. Patients with a reported variant in a non-SCN5A gene or with no reported variants were defined as patients with SCN5A-. All variants were classified as missense or predicted loss of function. RESULTS: A total of 500 BrS patients were analyzed. A total of 104 patients (20.8%) were SCN5A+ and 396 patients (79.2%) were SCN5A-. A non-SCN5A gene variant was found in 75 patients (15.0%), of whom, 58 patients (77.3%) had a missense variant and 17 patients (22.7%) had a predicted loss of function variant. At a follow-up of 84.0 months, 48 patients (9.6%) experienced a ventricular arrhythmia (VA). Patients without any variant had higher VA-free survival, compared with carriers of a predicted loss of function variant in SCN5A+ or non-SCN5A genes. There was no difference in VA-free survival between patients without any variant and missense variant carriers in SCN5A+ or non-SCN5A genes. At Cox analysis, SCN5A+ or non-SCN5A predicted loss of function variant was an independent predictor of VA. CONCLUSIONS: In a large BrS cohort, the yield for SCN5A+ is 20.8%. A predicted loss of function variant carrier is an independent predictor of VA.

Pulsed field ablation of the right superior pulmonary vein prevents vagal responses via anterior right ganglionated plexus modulation.

BACKGROUND: Pulsed field ablation (PFA) is selective for the myocardium. However, vagal responses and reversible effects on ganglionated plexi (GP) are observed during pulmonary vein isolation (PVI). Anterior-right GP ablation has been proven to effectively prevent vagal responses during radiofrequency-based PVI. OBJECTIVE: The purpose of this study was to test the hypothesis that PFA-induced transient anterior-right GP modulation when targeting the right superior pulmonary vein (RSPV) before any other pulmonary veins (PVs) may effectively prevent intraprocedural vagal responses. METHODS: Eighty consecutive paroxysmal atrial fibrillation patients undergoing PVI with PFA were prospectively included. In the first 40 patients, PVI was performed first targeting the left superior pulmonary vein (LSPV-first group). In the last 40 patients, RSPV was targeted first, followed by left PVs and right inferior PV (RSPV-first group). Heart rate (HR) and extracardiac vagal stimulation (ECVS) were evaluated at baseline, during PVI, and postablation to assess GP modulation. RESULTS: Vagal responses occurred in 31 patients (78%) in the LSPV-first group and 5 (13%) in the RSPV-first group (P <.001). Temporary pacing was needed in 14 patients (35%) in the LSPV-first group and 3 (8%) in the RSPV-first group (P = .003). RSPV isolation was associated with similar acute HR increase in the 2 groups (13 ± 11 bpm vs 15 ± 12 bpm; P = .3). No significant residual changes in HR or ECVS response were documented in both groups at the end of the procedure compared to baseline (all P >.05). CONCLUSION: PVI with PFA frequently induced vagal responses when initiated from the LSPV. Nevertheless, an RSPV-first approach promoted transient HR increase and reduced vagal response occurrence.

Lower rate of major bleeding in very high risk patients undergoing left atrial appendage occlusion: A propensity score-matched comparison with direct oral anticoagulation.

BACKGROUND: Long-term oral anticoagulation is the mainstay therapy for thromboembolic (TE) prevention in patients with atrial fibrillation. However, left atrial appendage occlusion (LAAO) could be a safe alternative to direct oral anticoagulants (DOACs) in patients with a very high TE risk profile. OBJECTIVE: The purpose of this study was to compare the safety and efficacy of LAAO vs DOACs in patients with atrial fibrillation at very high stroke risk (CHA2DS2-VASc [congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65-74 years, sex category] score ≥ 5). METHODS: Data from patients with CHA2DS2-VASc score ≥ 5 were extracted from a prospective multicenter database. To attenuate the imbalance in covariates between groups, propensity score matching was used (covariates: CHA2DS2-VASc and HAS-BLED [hypertension, abnormal renal or liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol] scores), which resulted in a matched population of 277 patients per group. The primary end point was a composite of cardiovascular death, TE events, and clinically relevant bleeding during follow-up. RESULTS: Of 2381 patients, 554 very high risk patients were included in the study (mean age 79 ± 7 years; CHA2DS2-VASc score 5.8 ± 0.9; HAS-BLED score 3.0 ± 0.9). The mean follow-up duration was 25 ± 11 months. A higher incidence of the composite end point was documented with DOACs compared with LAAO (14.9 events per 100 patient-years in the DOAC group vs 9.4 events per 100 patient-years in the LAAO group; P = .03). The annualized clinically relevant bleeding risk was higher with DOACs (6.3% vs 3.2%; P = .04), while the risk of TE events was not different between groups (4.1% vs 3.2%; P = .63). CONCLUSION: In high-risk patients, LAAO had a similar stroke prevention efficacy but a significantly lower risk of clinically relevant bleeding when compared with DOACs. The clinical benefit of LAAO became significant after 18 months of follow-up.

Posterior wall isolation via a multi-electrode radiofrequency balloon catheter: feasibility, technical considerations, endoscopic findings and comparison with cryoballoon technologies.

BACKGROUND: Posterior wall (PW) isolation is an important adjunctive ablation target in patients with non-paroxysmal atrial fibrillation (AF). Traditionally performed with point-by-point radiofrequency (RF) ablation, PW isolation has also been performed with different cryoballoon technologies. We aimed at assessing the feasibility of PW isolation with the novel RF balloon catheter Heliostar™ (Biosense Webster, CA, USA). METHODS: We prospectively enrolled 32 consecutive patients with persistent AF scheduled for first-time ablation with the Heliostar™ device. Procedural data were compared with those from 96 consecutive persistent AF patients undergoing pulmonary vein (PV) plus PW isolation with a cryoballoon device. The ratio RF balloon/cryoballoon was 1:3 for each operator involved in the study, aiming at avoiding any imbalance related to different experience. RESULTS: Single-shot PV isolation was documented in a significantly higher number of cases with the RF balloon technology compared to cryoballoon ablation (89.8% vs. 81.0%; p = 0.02, respectively). PW isolation was achieved with a similar number of balloon applications between the two groups (11 ± 4 with the RF balloon versus 11 ± 2 with the cryoballoon; p = 0.16), but in a significantly shorter time among RF balloon patients (228 ± 72 s versus 1274 ± 277 s with cryoballoon; p < 0.001). Primary safety endpoint occurred in none of the RF balloon patients versus 5 (5.2%) patients in the cryoballoon group (p = 0.33). Primary efficacy endpoint was achieved in all (100%) RF balloon patients versus 93 (96.9%) cryoballoon ones (p = 0.57). Oesophageal endoscopy did not show any signs of thermal lesions in RF balloon patients with luminal temperature rise. CONCLUSIONS: RF balloon-based PW isolation was safe and promoted shorter procedure times compared to similar cryoballoon-based ablation procedures.

Coronary artery disease in atrial fibrillation ablation: impact on arrhythmic outcomes.

AIMS: Catheter ablation (CA) is an established treatment for atrial fibrillation (AF). A computed tomography (CT) may be performed before ablation to evaluate the anatomy of pulmonary veins. The aim of this study is to investigate the prevalence of patients with coronary artery disease (CAD) detected by cardiac CT scan pre-ablation and to evaluate the impact of CAD and revascularization on outcomes after AF ablation. METHODS AND RESULTS: All consecutive patients with AF diagnosis, hospitalized at Universitair Ziekenhuis Brussel, Belgium, between 2015 and 2019, were prospectively screened for enrolment in the study. Inclusion criteria were (i) AF diagnosis, (ii) first procedure of AF ablation with cryoballoon CA, and (iii) contrast CT scan performed pre-ablation. A total of 576 consecutive patients were prospectively included and analysed in this study. At CT scan, 122 patients (21.2%) were diagnosed with CAD, of whom 41 patients (7.1%) with critical CAD. At survival analysis, critical CAD at CT scan was a predictor of atrial tachyarrhythmia (AT) recurrence during the follow-up, only in Cox univariate analysis [hazard ratio (HR) = 1.79] but was not an independent predictor in Cox multivariate analysis. At Cox multivariate analysis, independent predictors of AT recurrence were as follows: persistent AF (HR = 2.93) and left atrium volume index (HR = 1.04). CONCLUSION: In patients undergoing CT scan before AF ablation, critical CAD was diagnosed in 7.1% of patients. Coronary artery disease and revascularization were not independent predictors of recurrence; thus, in this patient population, AF ablation should not be denied and can be performed together with CAD treatment.

Redo procedures after sinus node sparing hybrid ablation for inappropriate sinus tachycardia/postural orthostatic sinus tachycardia.

AIMS: A novel sinus node (SN) sparing hybrid ablation for inappropriate sinus node tachycardia (IST)/postural orthostatic tachycardia syndrome (POTS) has been demonstrated to be an effective and safe therapeutic option in patients with symptomatic drug-resistant IST/POTS. The aim of this study was to evaluate the long-term rate of redo procedures after hybrid IST ablation and procedural strategy, outcomes and safety of redo procedures. METHODS AND RESULTS: All consecutive patients from 2015 to 2023 were prospectively enrolled in the UZ Brussel monocentric IST/POTS registry. They were analysed if the following inclusion criteria were fulfilled: 1) diagnosis of IST or POTS, 2) symptomatic IST/POTS refractory or intolerant to drugs, and 3) hybrid SN sparing ablation performed. The primary endpoint was redo procedure. The primary safety endpoint was pacemaker (PM) implantation. A total of 220 patients undergone to hybrid IST ablation were included, 185 patients (84.1%) were treated for IST and 61 patients (27.7%) for POTS.After a follow-up of 73.3 ± 16.2 months, 34 patients (15.4%) underwent a redo. A total of 23 patients (67.6%) had a redo for IST recurrence and 11 patients (32.4%) for other arrhythmias. Pacemaker implantation was performed in 21 patients (9.5%). Nine patients (4.1%) had no redo procedure and experienced sick sinus syndrome requiring a PM. Twelve patients (5.4%) received a PM as a shared therapeutic choice combined with SN ablation procedure. CONCLUSION: In a large cohort of patients the long-term free survival from redo procedure after hybrid IST ablation was 84.6% with a low PM implantation rate.

Safety of the Radiofrequency Balloon for Pulmonary Vein Isolation: A Focus on Lesion Metric Analysis of Posterior Electrodes.

Previous clinical studies on pulmonary vein isolation (PVI) with radiofrequency balloons (RFB) reported safe and effective procedures for a 20 s RF delivery via posterior electrodes. Recent recommendations from the manufacturer suggest reducing the application time to 15 s on the posterior wall (PW) when facing the esophagus region. Here, we retrospectively assess whether 15 s of RF delivery time on posterior electrodes is safe while still ensuring lesion metrics of sufficient quality. This retrospective study included 133 patients with paroxysmal and persistent atrial fibrillation who underwent PVI using an RFB (Heliostar, Biosense Webster, Inc., Irvine, CA, USA) at two European centers. The ablation protocol was set for an RF duration of 20 s/60 s for the posterior/anterior electrodes. A multielectrode temperature probe was systematically used. In the case of an esophageal temperature rise (ETR) above 42 °C (ETR+), an endoscopic evaluation was performed. All posterior electrode lesion metric dynamics (temperature (T) and impedance (Z)) were collected from the RFB generator and analyzed offline. In total, 2435 posterior electrode applications were analyzed. With an RF delivery of 19.8 (19.7-19.8) s, the median impedance drop was 18.4 (12.2-25.2) Ω, while the temperature rise was 11.1 (7.1-14.9) °C. Accordingly, impedance (84.6 (79.3-90.2) Ω) and temperature plateaus (38 (35.3-41.1) °C) were reached at 13.9 (10.6-16) s and 16.4 (12.6-18.5) s, respectively. Overall, 99.6% and 95.8% of electrodes reached 90% (16.6 Ω) and 95% (17.5 Ω) of their impedance drops within 15 s of RF delivery, while 97.2% and 92.8% achieved 90% (34.2 °C) and 95% (36.1 °C) of their temperature rise to reach the plateaus within 15 s of RF delivery. An ETR >42 °C occurred in 37 (30.1%) patients after 17.7 ± 2.3 s of RF delivery. In the ETR+ group, the impedance drop and temperature rise on the posterior electrodes were higher compared to patients where ETR was <42 °C. Two asymptomatic thermal esophageal injuries were observed. In conclusion, 15 s of RF delivery on the posterior electrodes provides a good balance between safety, with no esophageal temperature rise, and efficacy with high-profile lesion metrics.

Prognostic value of chronic kidney disease in patients undergoing left atrial appendage occlusion.

AIMS: Atrial fibrillation (AF) and chronic kidney disease (CKD) often coexist and share an increased risk of thrombo-embolism (TE). CKD concomitantly predisposes towards a pro-haemorrhagic state. Our aim was to evaluate the prognostic value of CKD in patients undergoing percutaneous left atrial appendage occlusion (LAAO). METHODS AND RESULTS: A total of 2124 consecutive AF patients undergoing LAAO were categorized into CKD stage 1+2 (n = 1089), CKD stage 3 (n = 796), CKD stage 4 (n = 170), and CKD stage 5 (n = 69) based on the estimated glomerular filtration rate at baseline. The primary endpoint included cardiovascular (CV) mortality, TE, and major bleeding. The expected annual TE and major bleeding risks were estimated based on the CHA2DS2-VASc and HAS-BLED scores. A non-significant higher incidence of major peri-procedural adverse events (1.7 vs. 2.3 vs. 4.1 vs. 4.3) was observed with worsening CKD (P = 0.14). The mean follow-up period was 13 ± 7 months (2226 patient-years). In comparison to CKD stage 1+2 as a reference, the incidence of the primary endpoint was significantly higher in CKD stage 3 (log-rank P-value = 0.04), CKD stage 4 (log-rank P-value = 0.01), and CKD stage 5 (log-rank P-value = 0.001). Left atrial appendage occlusion led to a TE risk reduction (RR) of 72, 66, 62, and 41% in each group. The relative RR of major bleeding was 58, 44, 51, and 52%, respectively. CONCLUSION: Patients with moderate-to-severe CKD had a higher incidence of the primary composite endpoint. The relative RR in the incidence of TE and major bleeding was consistent across CKD groups.

Quantitative assessment of transient autonomic modulation after single-shot pulmonary vein isolation with pulsed-field ablation.

INTRODUCTION: Pulmonary vein isolation (PVI) with thermal energy is characterized by concomitant ablation of the surrounding ganglionated plexi (GP). Pulsed-field ablation (PFA) selectively targets the myocardium and seems associated with only negligible effects on the autonomic nervous system (ANS). However, little is known about the dynamic effects of PFA on the GP immediately after PVI. This study sought to investigate the degree and acute vagal modulation induced by the FarapulseTM PFA system during PVI compared with single-shot thermal ablation. METHODS: A total of 76 patients underwent first-time PVI with either FarapulseTM PFA (PFA group, n = 40) or cryoballoon ablation (thermal ablation group, n = 36) for paroxysmal atrial fibrillation (AF). The effect on the ANS in the two groups was assessed before and after PVI with extracardiac vagal stimulation (ECVS). To capture any transient effects of PFA on the ANS, in a subgroup of PFA patients ECVS was repeated at three predefined timepoints: (1) before PVI (T0); (2) immediately after PVI (T1); and (3) 10 min after the last energy application (T2). RESULTS: Despite similar baseline values, the vagal response induced by ECVS after PVI almost disappeared in the thermal ablation group but persisted in the PFA group (thermal group: 840 [706-1090] ms, p < .001 compared to baseline; PFA group: 11 466 [8720-12 293] ms, p = .70 compared to baseline). Intraprocedural vagal reactions (defined as RR increase >50%, transitory asystole, or atrioventricular block) occurred more frequently with PFA than thermal ablation (70% vs. 28%, p = .001). Moreover, heart rate 24 h post-PVI increased more with thermal ablation than with PFA (16.5 ± 9.0 vs. 2.6 ± 6.1 beats/min, p < .001). In the subgroup of PFA patients undergoing repeated ANS modulation assessment (n = 11), ECVS demonstrated that PFA determined a significant acute suppression of the vagal response immediately after PVI (p < .001 compared to baseline), which recovered almost completely within 10 min. CONCLUSION: PVI with the FarapulseTM PFA system is associated with only transitory and short-lasting vagal effects on the ANS which recover almost completely within a few minutes after ablation. The impact of this phenomenon on AF outcome needs to be further investigated.

Outcomes of pulmonary vein isolation with radiofrequency balloon vs. cryoballoon ablation: a multi-centric study.

AIMS: Cryoballoon (CB) ablation is the mainstay of single-shot pulmonary vein isolation (PVI). A radiofrequency balloon (RFB) catheter has recently emerged as an alternative. However, these two technologies have not been compared. This study aims to evaluate the freedom from atrial tachyarrhythmias (ATas) at 1 year: procedural characteristics, efficacy, and safety of the novel RFB compared with CB for PVI in patients with paroxysmal atrial fibrillation (AF). METHODS AND RESULTS: This prospective multi-centre study included consecutive patients with symptomatic drug-resistant paroxysmal AF who underwent PVI with RFB or CB between July 2021 and January 2022 from three European centres. A total of 375 consecutive patients were included, 125 in the RFB group and 250 in the CB. Both groups had comparable clinical characteristics. At 12.33 ± 4.91 months, ATas-free rates were 83.20% and 82.00% in the RFB and CB groups, respectively (P > 0.05). Compared with the CB group, the RFB group showed a shorter procedure time [59.91 (45.80-77.12) vs. 77.0 (35.13-122.71) min (P < 0.001)], dwell time [19.59 (14.41-30.24) vs. 27.03 (17.11-57.21) min (P = 0.04)], time to isolation, and thermal energy delivery in all pulmonary veins (P < 0.001). First-pass isolation was comparable. No major complications occurred in either group, with no stroke, atrio-oesophageal fistula, or permanent phrenic nerve injury. Transient phrenic nerve palsy occurred more frequently with CB than RFB (7.20% vs. 3.20%; P = 0.02). Oesophageal temperature rise occurred in 21 (16.8%) patients in the RFB group, and gastroscopy showed erythema in two of them with complete recovery after 30 days. CONCLUSIONS: The RFB appears to have a safety and efficacy profile similar to that of the CB for PVI. Shorter procedural times appear to be driven by shorter left atrial dwell and thermal delivery times.

Atrial Abnormalities in Brugada Syndrome: Evaluation With ECG Imaging.

BACKGROUND: Patients with Brugada syndrome (BrS) have an increased risk of arrhythmias, including atrial tachyarrhythmias (ATas). OBJECTIVES: The purpose of this study was to assess underlying atrial cardiomyopathy in BrS and the effect of ajmaline (AJM) test on the atrium of BrS patients using electrocardiogram imaging (ECGI). METHODS: All consecutive patients diagnosed with BrS in a monocentric registry were screened and included if they met the following criteria: 1) BrS diagnosed following current recommendations; and 2) ECGI map performed before and after AJM with a standard protocol. Consecutive patients with no structural heart disease or BrS who had undergone ECGI were included as a control group. Genetic analysis for SCN5A was performed in all BrS patients. Total atrial conduction time (TACT) and local atrial conduction time (LACT) were calculated from atrial ECGI. The primary endpoint was ATas during follow-up. RESULTS: Forty-three consecutive BrS patients and 40 control patients were included. Both TACT and LACT were significantly prolonged in BrS patients compared with control patients. Furthermore, TACT and LACT were significantly higher after AJM administration and in BrS patients who were carriers of a pathogenic/likely pathogenic SCN5A variant. After a mean follow-up of 40.9 months, 6 patients experienced a first ATa occurrence (all in the BrS group, 13.9%). TACT was the only independent predictor of ATas with a cutoff of >138.5 ms (sensitivity 0.92 [95% CI: 0.83-0.98], specificity 0.70 [95% CI: 0.59-0.81]). CONCLUSIONS: ECGI-calculated TACT and LACT are significantly prolonged in BrS patients compared with control patients, and in BrS patients after AJM. This may be consistent with a concealed atrial cardiomyopathy in BrS.

"Function follows form": Role of cardiac magnetic resonance for ventricular arrhythmia risk stratification in patients with cardiac sarcoidosis.

INTRODUCTION: Cardiac involvement is common and may become clinically relevant in approximately 5%-10% of patients with systemic sarcoidosis. Although reduced left ventricular ejection fraction is a recognized predictor of mortality, recent studies have suggested an increased risk of ventricular arrhythmia (VAs) and sudden cardiac death (SCD) in patients with cardiac sarcoidosis (CS) and evidence of late gadolinium enhancement-cardiac magnetic resonance (LGE-CMR), irrespective of the underlying left ventricular systolic function. We performed a meta-analysis to assess the correlation between VAs/SCD and presence of LGE-CMR in CS patients. METHODS: We systematically searched Medline, Embase, and Cochrane electronic databases up to January 2, 2023, for studies enrolling patients with suspected or confirmed CS undergoing LGE-CMR. Clinical outcomes of interest included clinically relevant VAs, defined as sustained ventricular tachycardia, ventricular fibrillation, SCD, or aborted SCD during follow-up. The effect size was estimated using a random-effect model as risk ratio (RR) and relative 95% confidence interval (CI). RESULTS: A total of 14 studies fulfilled the selection criteria and were included in the final analysis. Among 1273 patients, LGE was detected in 465 (36.5%; Group LGE+). Males accounted for 45.2% (95% CI: 40.5%-55.7%) of the total population and the average age was 56.8 (95% CI: 52.7%-60.9) years. A total of 104 (22.3%) of 465 LGE+ patients experienced a clinically relevant VA, compared to 6 (0.7%) of 808 LGE- ones. LGE+ was associated with a ninefold increased risk in life-threatening VAs (22.3% vs. 0.7%; RR = 9.52; 95% CI [5.18-17.49]; p < .0001) compared to patients without LGE (heterogeneity I2 = 0%). CONCLUSION: In our meta-analysis, LGE+ in patients with CS was associated with a ninefold increased risk in life-threatening VAs compared to patients without LGE.