Diagnostic yield of implantable loop recorders: Results from the Hellenic registry.

AIMS: Implantable loop recorders (ILRs) are increasingly being used for long-term cardiac monitoring in different clinical settings. The aim of this study was to investigate the real-world performance of ILRs-including the time to diagnosis- in unselected patients with different ILR indications. METHODS AND RESULTS: In this multicenter, observational study, 871 patients with an indication of pre-syncope/syncope (61.9%), unexplained palpitations (10.4%), and atrial fibrillation (AF) detection with a history of cryptogenic stroke (CS) (27.7%) underwent ILR implantation. The median follow-up was 28.8 ± 12.9 months. In the presyncope/syncope group, 167 (31%) received a diagnosis established by the device. Kaplan-Meier estimates indicated that 16.9% of patients had a diagnosis at 6 months, and the proportion increased to 22.5% at 1 year. Of 91 patients with palpitations, 20 (22%) received a diagnosis based on the device. The diagnosis established at 12.2% of patients at 6 months, and the proportion increased to 13.3% at 1 year. Among 241 patients with CS, 47 (19.5%) were diagnosed with AF. The diagnostic yield of the device was 10.4% at 6 months and 12.4% at 1 year. In all cases, oral anticoagulation was initiated. Overall, ILR diagnosis altered the therapeutic strategy in 26.1% in presyncope/syncope group, 2.2% in palpitations group, and 3.7% in CS group in addition to oral anticoagulation initiation. CONCLUSIONS: In this real-world patient population, ILR determines diagnosis and initiates a new therapeutic management in nearly one fourth of patients. ILR implantation is valuable in the evaluation of patients with unexplained presyncope/syncope, CS and palpitations.

Efficacy and safety of colchicine for atrial fibrillation prevention: An updated meta-analysis of randomized controlled trials.

BACKGROUND: Atrial fibrillation (AF), the most common arrhythmia, is closely related to inflammation. Colchicine has the potent anti-inflammatory effects. Several randomized clinical trials (RCTs) have evaluated the efficacy and safety of colchicine in the prevention of AF but the results are inconsistent. OBJECTIVE: The purpose of our study was to evaluate the impact of colchicine on AF. METHOD AND RESULTS: PubMed, EMBASE, Web of Science, Cochrane Library and ClinicalTrials.gov were searched for related studies until Jan 8, 2024. A total of 17 studies including 16,238 participants were included. Compared to the placebo group, there were fewer incidences of AF in the colchicine group (RR: 0.75, 95%CI: 0.68-0.83, P < 0.001). The incidence of overall adverse events and overall gastrointestinal intolerance did not differ significantly between the two groups. However, diarrhea, nausea, and discontinuation occurred more frequently in patients treated with colchicine. CONCLUSION: Colchicine can prevent patients from the incidence of AF, regardless of the mean age of patients, type of atrial fibrillation, maintenance dose, duration of colchicine use, cumulative daily dose, and follow-up time with more diarrhea, nausea and discontinuation. These adverse events can be avoided by low doses (0.5 mg once daily) and long period time of colchicine use.

Analysis of the Effectiveness of the Latest 4th Generation Cryoballoon Catheters in Pulmonary Vein Isolation Using High-Resolution Mapping.

BACKGROUND: Long-term data showed that up to 27% of pulmonary veins are reconnected using cryoballoon ablation. This study aims to evaluate the efficacy of the latest 4th generation cryoballoon catheters using ultra high-resolution mapping. METHODS: In patients with AF, a standard PVI with the latest 4th generation cryoballoon catheter (Arctic Front Advance PRO, Medtronic Minneapolis, USA) and the spiral mapping catheter (Achieve Advance, Medtronic, Minneapolis, MN, USA) was performed. Subsequently, high-resolution mapping was achieved using the novel multipolar grid mapping catheter (Advisor HD Grid SE, Abbott Laboratories; USA). Follow-up was obtained after 6 months by means of a 7-day Holter ECG. RESULTS: In our study, acute PVI was successfully achieved in all 31 patients. The latest 4th generation cryoballoon catheter is safe in the acute phase of PVI. Additional high-resolution mapping (mean points per map 21001 ± 4911) using the multipolar grid mapping catheter enabled us to identify residual gaps only in the carina PV region; therefore, no additional ablation was performed. Three out of 31 patients (10%) presented with atrial arrhythmia recurrence always related with PV reconnection; using high-resolution mapping had no additional benefit in identifying pulmonary veins in which reconnection will occur. CONCLUSION: The utility of additional high-density mapping, facilitated by the HD Grid catheter following PVI with the fourth-generation cryoballoon catheter do not substantiate a discernible advantage over conventional mapping methodologies, particularly the spiral mapping catheter. Residual carinal conduction was observed in a substantial cohort of patients (48%), highlighting a persistent challenge in achieving complete electrical isolation.

Atrial fibrillation in the setting of cardiac amyloidosis - A review of the literature.

Cardiac amyloidosis (CA) is related to the aggregation of insoluble fibrous deposits of misfolded proteins within the myocardium. Transthyretin amyloidosis (ATTR) and immunoglobulin light-chain amyloidosis are the main forms of CA. Atrial fibrillation (AF) is a common arrhythmia in CA patients, especially in those with ATTR amyloidosis. Increased atrial preload and afterload, atrial enlargement, enhanced atrial wall stress, and autonomic dysfunction are the main mechanisms of AF in CA patients. CA is associated with the formation of endocardial thrombi and systemic embolism. The promoters of thrombogenesis include endomyocardial damage, blood stasis, and hypercoagulability. The prevalence of thrombi in patients with AF remains elevated despite long-term anticoagulation. Consequently, transesophageal ultrasound examinations before cardioversion should be performed to exclude endocardiac thrombi despite anticoagulation. Furthermore, the CHA2DS2-VASc score should not be used to assess the thromboembolic risk in CA patients with AF. Rate control is challenging in patients with CA, while rhythm control is the preferred treatment option, especially in the early stages of the disease process. Although catheter ablation is an effective treatment option, more data are needed to explore the role of the procedure in CA patients.

Cryoablation versus hybrid radiofrequency with high- and very-high-power short-duration catheter ablation for the treatment of paroxysmal atrial fibrillation.

BACKGROUND: High-power short-duration (HPSD) and very-high-power short-duration (vHPSD-90 W/4 s) radiofrequency (RF) technology has reduced the procedure time of pulmonary vein isolation (PVI) using RF without compromising the efficacy of the technique. The current study compares the novel technology of HPSD/vHPSD with cryoablation (CRYO) in terms of efficacy, safety, and procedure time in a cohort of symptomatic patients with paroxysmal atrial fibrillation (pAF). METHODS: This is a prospective, non-randomized trial. Patients with pAF received either CRYO or HPSD/vHPSD RF PVI. The primary endpoint of the study was arrhythmia recurrence in a 12 month follow-up period. Secondary endpoints included procedure time, fluoroscopy time, and safety. RESULTS: 104 patients were included (45 in HPSD/vHPSD and 59 in CRYO), with comparable characteristics between groups. The follow-up was 12.4 ± 0.5 months. There was no significant difference regarding arrhythmia recurrences during the early post-procedural period of the first 3 months (8.9% recurrences in HPSD/vHPSD versus 5.1% in CRYO-p 0.463) and in the mid-term follow-up of 12 months (17.8% recurrences in HPSD/vHPSD versus 10.2% in CRYO-p 0.385). Safety was excellent for both procedures. CRYO was a procedure of significantly shorter duration (64.64 ± 8.94 min versus 75.29 ± 18.30 min, p = 0.0001) at the expense of longer fluoroscopy time (HPSD/vHPSD 5.34 ± 1.83 versus 7.89 ± 3.70 min CRYO, p 0.001). CONCLUSIONS: HPSD/vHPSD and CRYO in pAF were comparable regarding the arrhythmia recurrence rates in a 12-month follow-up with excellent safety. The hybrid approach of HPSD/vHPSD has accelerated RF-PVI compared to conventional RF, but CRYO remains a procedure of significantly shorter duration at the expense of longer fluoroscopy time.

Cardiac contractility modulation in patients with heart failure - A review of the literature.

Experimental in vivo and in vitro studies showed that electric currents applied during the absolute refractory period can modulate cardiac contractility. In preclinical studies, cardiac contractility modulation (CCM) was found to improve calcium handling, reverse the foetal myocyte gene programming associated with heart failure (HF), and facilitate reverse remodeling. Randomized control trials and observational studies have provided evidence about the safety and efficacy of CCM in patients with HF. Clinically, CCM therapy is indicated to improve the 6-min hall walk, quality of life, and functional status of HF patients who remain symptomatic despite guideline-directed medical treatment without an indication for cardiac resynchronization therapy (CRT) and have a left ventricular ejection fraction (LVEF) ranging from 25 to 45%. Although there are promising results about the role of CCM in HF patients with preserved LVEF (HFpEF), further studies are needed to elucidate the role of CCM therapy in this population. Late gadolinium enhancement (LGE) assessment before CCM implantation has been proposed for guiding the lead placement. Furthermore, the optimal duration of CCM application needs further investigation. This review aims to present the existing evidence regarding the role of CCM therapy in HF patients and identify gaps and challenges that require further studies.

Association of Late Potentials With Fatal Arrhythmic Events in Patients With Brugada Syndrome-A Meta-analysis.

Risk stratification of patients with Brugada syndrome (BrS) remains challenging. Signal-averaged electrocardiogram (SAECG) is a noninvasive tool that can be used to identify the electrophysiologic substrate potentially underlying fatal ventricular arrhythmias. The aim of this meta-analysis is to summarize the existing evidence about the role of late potentials (LP) as a predictor for arrhythmic events in patients with BrS. A systematic search in the MedLine database through to June 2022 without any limitations was performed. Ten studies were included in the quantitative synthesis (1431 patients with BrS, mean age 47.4 years, males 86%). Of these, 1220 patients underwent SAECG evaluation (53.2% had positive LP, and 20.6% had a fatal arrhythmic event). There was a nonsignificant association between positive LPs and fatal arrhythmic events [RR: 2.06 (0.98-4.36), P = 0.06, I2 = 82%]. By including only studies with patients without a history of fatal arrhythmia, the association between LP with arrhythmic events remained nonsignificant [RR: 1.29 (0.67-2.48), P = 0.44, I2 = 54%]. In conclusion, there is a possible association between LP and fatal arrhythmic events in patients with BrS, but the literature remains inconclusive. Large cohort studies using a multiparametric approach for risk stratification purposes are needed to improve the risk stratification of BrS and to optimize the selection of BrS patients that should be referred for implantable cardioverter-defibrillator.

An inappropriately-appropriate ICD therapy: What is the mechanism and what interventions can be done?

Key Clinical Message: R-wave double counting is a rare cause of ventricular oversensing that can lead to inappropriate shocks. Optimizing device programming is essential for the avoidance of subsequent inappropriate therapies. Abstract: R-wave double counting is a rare cause of ventricular oversensing that can lead to inappropriate shocks. We present the case of a female patient, 52-years-old with a history of end-stage hypertrophic cardiomyopathy. The patient suffered an implantable cardioverter-defibrillator (ICD) shock. Cardiac device interrogation revealed ventricular tachycardia (VT) with a cycle length of 420 ms that was misclassified in the ventricular fibrillation (VF) zone owing to R-wave double counting. Optimizing device programming is essential for the avoidance of subsequent inappropriate therapies. Possible therapeutic options are briefly presented in the case.

Contemporary management of ventricular arrhythmias in heart failure.

Enhanced ventricular arrhythmogenesis is commonly experienced by patients in the end-stage of heart failure spectrum. A high burden of ventricular arrhythmias can affect the ventricular systolic function, lead to unexpected hospitalizations and further deteriorate the prognosis. Management of ventricular arrhythmias in this population is challenging. Implantable cardioverter-defibrillators are protective for the immediate termination of life-threatening arrhythmias but they have no impact in reducing the arrhythmic burden. Combination treatment with invasive (catheter ablation, mechanical hemodynamic support, sympathetic denervation) and noninvasive (antiarrhythmic drugs, medical therapy for heart failure, programming of implantable devices) therapies is commonly required. The aim of this review is to present the available therapeutic options, with main focus on recently published data for catheter ablation and provide a stepwise treatment approach.

Cardioneuroablation for neurally-mediated syncope: Initial experience.

Cardioneuroablation is an emerging alternative therapeutic modality for young patients with severe neurally-mediated syncope. We present two images of cardioneuroablation performed in young patients who suffered from recurrent neurally-mediated syncope with asystole and functional atrioventricular block. The patients remain syncope-free during follow-ups.

Electrocardiographic changes after balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension: Data from the Hellenic Registry.

BACKGROUND: Balloon pulmonary angioplasty (BPA) has provided an effective invasive treatment for inoperable patients with chronic thromboembolic pulmonary hypertension (CTEPH). The hemodynamic improvement achieved by BPA has significantly increased the long-term prognosis of these patients, mostly by reversing the negative remodeling of the right ventricle (RV). MATERIALS AND METHODS: In a cohort of 17 patients with symptomatic CTEPH hemodynamic data were collected before and after the completion of BPA sessions. After the confirmation of statistically significant hemodynamic improvement, we examined the changes in certain prespecified electrocardiographic (ECG) parameters (PR interval duration, QRS duration, QTc interval duration, R wave and S wave amplitude in lead I, R wave and S wave amplitude in precordial leads V1, V5 and V6) before the initiation and one month after the completion of BPA sessions. In addition, ECGs were qualitatively assessed before and after treatment for the presence of ECG abnormalities related to PH, proposed by the guidelines of the European Society of Cardiology (ESC). The term ESC criteria 1-6 was used for their description. RESULTS: Statistically significant correlation (p < 0.05) was found between the reduction in mean pulmonary artery pressure (mPAP) and the decrease of the depth of the S wave in leads I (p 0.0069), V5 (p 0.0003), V6 (p 0.0011) and in the R wave amplitude in leads V5 (p 0.0122) and V6 (p 0.0185). From the ESC criteria, RV strain pattern was the commonest in the initial cohort, with significant improvement after therapies. CONCLUSION: Hemodynamic improvement after BPA therapies is correlated with improved ECG amplitude parameters in leads I, V5 and V6. RV strain pattern is common among untreated patients with significant improvement after therapies.

Secular trends of health care resource utilization and costs between Brugada syndrome and congenital long QT syndrome: A territory-wide study.

BACKGROUND: Health care resource utilization (HCRU) and costs are important metrics of health care burden, but they have rarely been explored in the setting of cardiac ion channelopathies. HYPOTHESIS: This study tested the hypothesis that attendance-related HCRUs and costs differed between patients with Brugada syndrome (BrS) and congenital long QT syndrome (LQTS). METHODS: This was a retrospective cohort study of consecutive BrS and LQTS patients at public hospitals or clinics in Hong Kong, China. HCRUs and costs (in USD) for Accident and Emergency (A&E), inpatient, general outpatient and specialist outpatient attendances were analyzed between 2001 and 2019 at the cohort level. Comparisons were made using incidence rate ratios (IRRs [95% confidence intervals]). RESULTS: Over the 19-year period, 516 BrS (median age of initial presentation: 51 [interquartile range: 38-61] years, 92% male) and 134 LQTS (median age of initial presentation: 21 [9-44] years, 32% male) patients were included. Compared to LQTS patients, BrS patients had lower total costs (2 008 126 [2 007 622-2 008 629] vs. 2 343 864 [2 342 828-2 344 900]; IRR: 0.857 [0.855-0.858]), higher costs for A&E attendances (83 113 [83 048-83 177] vs. 70 604 [70 487-70 721]; IRR: 1.177 [1.165-1.189]) and general outpatient services (2,176 [2,166-2,187] vs. 921 [908-935]; IRR: 2.363 [2.187-2.552]), but lower costs for inpatient stay (1 391 624 [1 391 359-1 391 889] vs. 1 713 742 [1 713 166-1 714 319]; IRR: 0.812 [0.810-0.814]) and lower costs for specialist outpatient services (531 213 [531 049-531 376] vs. 558 597 [558268-558926]; IRR: 0.951 [0.947-0.9550]). CONCLUSIONS: Overall, BrS patients consume 14% less health care resources compared to LQTS patients in terms of attendance costs. BrS patients require more A&E and general outpatient services, but less inpatient and specialist outpatient services than LQTS patients.

Radiofrequency versus cryoballoon catheter ablation in patients with persistent atrial fibrillation: A randomized trial.

INTRODUCTION: Patients with persistent atrial fibrillation (AF) represent a challenging population for rhythm control therapies. Catheter ablation (CA) with pulmonary vein isolation (PVI) is an effective treatment option for the reduction of the arrhythmic burden. Data regarding the comparability between radiofrequency (RF) and cryoballoon ablation (CRYO) in persistent AF are limited. METHODS: This is a prospective, randomized, single-center study designed to compare the efficacy in terms of rhythm control between RF and CRYO in persistent AF. Eligible participants were randomized 2:1 in two arms: RF and CRYO. The primary endpoint of the study was arrhythmia relapse in the early postprocedural period (first 3 months) and in the middle term follow-up (3 months to 12 months). Secondary endpoints included procedure duration, fluoroscopy time, and complications. RESULTS: A total of 199 patients participated in the study (133 patients in the RF arm, 66 in the CRYO arm). No statistically significant difference occurred between the two groups regarding the primary endpoint (recurrences ≤3 months: 35.5% RF vs. 37.9% CRYO, p .755, recurrences >3 months: 26.3% RF vs. 27.3% CRYO, p .999). From the secondary endpoints, CRYO was a procedure of significantly shorter duration (75.15 ± 17.21 in CRYO vs. 136.6 ± 43.33 in RF group, p < .05). CONCLUSION: CRYO and RF ablation appear to be equally effective for rhythm control in patients with persistent AF. CRYO ablation is advantageous in terms of procedure duration.

Predictors of Ventricular Arrhythmias in Patients With Mitral Valve Prolapse: A Meta-analysis.

Mitral valve prolapse (MVP) has an estimated prevalence of 2-3% in the general population. Patients with MVP have an increased risk of ventricular arrhythmic events. The aim of this meta-analysis was to identify easily obtained markers that can be used for the arrhythmic risk stratification of MVP patients. This meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA Statement). The search strategy identified 23 studies that were finally included in the study. The quantitative synthesis showed that late gadolinium enhancement (LGE) [RR 6.40 (2.11-19.39), I2 77%, P = 0.001], longer QTc interval [mean difference: 14.2 (8.92-19.49) I2 0%, P < 0.001], T-wave inversion in inferior leads [RR 1.60 (1.39-1.86), I2 0%, P < 0.001], mitral annular disjunction (MAD) [RR 1.77 (1.29-2.44), I2 37%, P = 0.0005], lower left ventricular ejection fraction (LVEF) [mean difference: -0.77 (-1.48, -0.07) I2 0%, P = 0.03], bileaflet MVP [RR 1.32 (1.16-1.49), I2 0%, P < 0.001], increased anterior [mean difference: 0.45 (0.28, 0.61), I2 0%, P < 0.001] and posterior [mean difference: 0.39 (0.26, 0.52), I2 0%, P < 0.001] mitral leaflet thickness were significantly associated with ventricular arrhythmias in MVP patients. On the other hand, gender, QRS duration, anterior, and posterior mitral leaflet length were not associated with increased risk of arrhythmias. In conclusion, inferior T-wave inversions, QTc interval, LGE, LVEF, MAD, bileaflet MVP, anterior, and posterior mitral leaflet thickness are easily obtained markers that can be used for the risk stratification of patients with MVP. Prospective studies should be designed for the better stratification of this population.

Diagnostic and therapeutic dilemmas in a patient with myocarditis, Brugada syndrome and arrhythmic syncope.

We present a case of a previously healthy 23-year-old male who presented with chest pain, palpitations and spontaneous type 1 Brugada electrocardiographic (ECG) pattern. Positive family history for sudden cardiac death (SCD) was remarkable. Initially, clinical symptoms in combination with myocardial enzymes elevation, regional myocardial oedema with late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and inflammatory lymphocytoid-cell infiltrates in the endomyocardial biopsy (EMB) suggested the diagnosis of a myocarditis-induced Brugada phenocopy (BrP). Under immunosuppressive therapy with methylprednisolone and azathioprine, a complete remission of both symptoms and biomarkers was accomplished. However, the Brugada pattern did not resolve. The eventually spontaneous Brugada pattern type 1 established the diagnosis of Brugada syndrome (BrS). Due to his previous history of syncope, the patient was offered an ICD that he declined. After his discharge he experienced a new episode of arrhythmic syncope. He was readmitted and received an ICD.

The Role of Electrophysiological Study in the Risk Stratification of Brugada Syndrome.

Brugada syndrome (BrS) is a complex arrhythmogenic disease associated with an increased risk of sudden cardiac death (SCD). The role of electrophysiological study (EPS) for risk stratification purposes of asymptomatic BrS patients remains still controversial. This study aims to summarize the existing data about the role of electrophysiological study for arrhythmic risk stratification of BrS patients without a prior history of aborted SCD or fatal arrhythmic event. Two independent investigators (G.B. and G.T.) performed a systematic search in the MedLine database and Cochrane library from their inception until April 2022 without any limitations. The reference lists of the relevant research studies as well as the relevant review studies and meta-analyses were manually searched. Nineteen studies were included in the final analysis. The included studies enrolled 6218 BrS patients (mean age: 46.9 years old, males: 76%) while 4265 (68.6%) patients underwent an EPS. The quantitative synthesis showed that a positive EPS study was significantly associated with arrhythmic events in BrS patients (RR, 1.74 [1.23-2.45]; P = 0.002; I2 = 63%]. By including the studies that provided data on the association of EPS with arrhythmic events during follow-up in patients without a prior history of aborted SCD or fatal arrhythmic event, the association between positive EPS study and future arrhythmic events remained significant (RR, 1.60 [1.08-2.36]; P = 0.02; I2 = 19%). In conclusion, EPS is a useful invasive tool for the risk stratification of BrS patients and can be used to identify the population of BrS patients who may be candidates for primary prevention of SCD with implantable cardioverter-defibrillator (ICD) implantation.

The value of functional substrate mapping in ventricular tachycardia ablation.

In the setting of structural heart disease, ventricular tachycardia (VT) is typically associated with a re-entrant mechanism. In patients with hemodynamically tolerated VTs, activation and entrainment mapping remain the gold standard for the identification of the critical parts of the circuit. However, this is rarely accomplished, as most VTs are not hemodynamically tolerated to permit mapping during tachycardia. Other limitations include noninducibility of arrhythmia or nonsustained VT. This has led to the development of substrate mapping techniques during sinus rhythm, eliminating the need for prolonged periods of mapping during tachycardia. Recurrence rates following VT ablation are high; therefore, new mapping techniques for substrate characterization are required. Advances in catheter technology and especially multielectrode mapping of abnormal electrograms has increased the ability to identify the mechanism of scar-related VT. Several substrate-guided approaches have been developed to overcome this, including scar homogenization and late potential mapping. Dynamic substrate changes are mainly identified within regions of myocardial scar and can be identified as local abnormal ventricular activities. Furthermore, mapping strategies incorporating ventricular extrastimulation, including from different directions and coupling intervals, have been shown to increase the accuracy of substrate mapping. The implementation of extrastimulus substrate mapping and automated annotation require less extensive ablation and would make VT ablation procedures less cumbersome and accessible to more patients.

Atrial cardiomyopathy: Diagnosis, clinical implications and unresolved issues in anticoagulation therapy.

Atrial cardiomyopathy (AC) is an evolving pathophysiological entity that has expanded our understanding regarding the atrium and its role in arrhythmogenesis and cardiac thromboembolism. The pathological myocardium in AC promotes arrhythmogenesis through mechanical dysfunction (hypocontractility, fibrosis), adverse alterations of the endothelium and secretion of prothrombotic factors (IL-6, IL-8, TNF-a). 'Red flags', indicative of AC, can be recognized either non-invasively by electrocardiography, echocardiography and cardiac magnetic resonance imaging or invasively by high-density electroanatomical mapping as low bipolar voltage areas of the affected myocardium. Signs of AC have been strongly associated with an increased risk of ischemic stroke, even embolic strokes of undetermined source, regardless of the coexistence of atrial fibrillation (AF). The underlying existence of AC has been negatively correlated with the success rate of catheter ablation of AF. The clinical value of AC is the provision of a novel pathway regarding the potential mechanisms of cerebrovascular events of cardiac thromboembolic origin. In addition, AC may serve as a risk stratification tool to predict the long-term responders of AF catheter ablation.

Comparing the Performance of Published Risk Scores in Brugada Syndrome: A Multi-center Cohort Study.

The management of Brugada Syndrome (BrS) patients at intermediate risk of arrhythmic events remains controversial. The present study evaluated the predictive performance of different risk scores in an Asian BrS population and its intermediate risk subgroup. This retrospective cohort study included consecutive patients diagnosed with BrS from January 1, 1997 to June 20, 2020 from Hong Kong. The primary outcome is sustained ventricular tachyarrhythmias. Two novel risk risk scores and 7 machine learning-based models (random survival forest, Ada boost classifier, Gaussian naïve Bayes, light gradient boosting machine, random forest classifier, gradient boosting classifier and decision tree classifier) were developed. The area under the receiver operator characteristic curve (AUC) [95% confidence intervals] was compared between the different models. This study included 548 consecutive BrS patients (7% female, age at diagnosis: 50 ± 16 years, follow-up: 84 ± 55 months). For the whole cohort, the score developed by Sieira et al showed the best performance (AUC: 0.806 [0.747-0.865]). A novel risk score was developed using the Sieira score and additional variables significant on univariable Cox regression (AUC: 0.855 [0.808-0.901]). A simpler score based on non-invasive results only showed a statistically comparable AUC (0.784 [0.724-0.845]), improved using random survival forests (AUC: 0.942 [0.913-0.964]). For the intermediate risk subgroup (N = 274), a gradient boosting classifier model showed the best performance (AUC: 0.814 [0.791-0.832]). A simple risk score based on clinical and electrocardiographic variables showed a good performance for predicting VT/VF, improved using machine learning.