Aims  Brugada syndrome (BrS) is associated with an increased risk of sudden cardiac death due to ventricular tachycardia/fibrillation (VT/VF) in young, otherwise healthy individuals. Despite SCN5A being the most commonly known mutated gene to date, the genotype–phenotype relationship is poorly understood and remains uncertain. This study aimed to elucidate the genotype–phenotype correlation in BrS. Methods and results Brugada syndrome probands deemed at high risk of future arrhythmic events underwent genetic testing and phenotype characterization by the means of epicardial arrhythmogenic substrate (AS) mapping, and were divided into two groups according to the presence or absence of SCN5A mutation. Two-hundred probands (160 males, 80%; mean age 42.6 ± 12.2 years) were included in this study. Patients harbouring SCN5A mutations exhibited a spontaneous type 1 pattern and experienced aborted cardiac arrest or spontaneous VT/VF more frequently than the other subjects. SCN5A-positive patients exhibited a larger epicardial AS area, more prolonged electrograms and more frequently observed non-invasive late potentials. The presence of an SCN5A mutation explained >26% of the variation in the epicardial AS area and was the strongest predictor of a large epicardial area. Conclusion  In BrS, the genetic background is the main determinant for the extent of the electrophysiological abnormalities. SCN5A mutation carriers exhibit more pronounced epicardial electrical abnormalities and a more aggressive clinical presentation. These results contribute to the understanding of the genetic determinants of the BrS phenotypic expression and provide possible explanations for the varying degrees of disease expression.

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Background Hydroxychloroquine (HCQ) and azithromycin (AZT) have been proposed for COVID-19 treatment. Data available in the literature reported a potential increased risk of fatal arrhythmias under these therapies. The aim of this study was to assess the effects of these drugs on QT interval and outcome in a COVID-19 population. Methods A total of 112 consecutive COVID-19 patients were included in this analysis and were divided in 3 groups according to the receiving therapeutic regimens: 19 (17%) patients in Group 1 (no treatment), 40 (36%) in Group 2 (HCQ only), 53 (47%) in Group 3 (HCQ/AZT). Results A prolonged QTc interval was found in 61% of patients treated with HCQ alone or in combination with AZT, but only 4 (4%) patients showed a QTc > 500 ms. HCQ/AZT combination determined a greater increase of QTc duration compared to the other two strategies (Group 3452 ± 26.4 vs Group 2436.3 ± 28.4 vs Group 1424.4 ± 24.3 ms, respectively; p < 0.001). Multivariate analysis demonstrated that HCQ/AZT combination (OR 9.02, p = 0.001) and older age (OR 1.04, p = 0.031) were independent predictors of QTc prolongation. The risk increased with age (incremental utility analysis p = 0.02). Twenty patients (18%) died, and no cardiac arrest neither arrhythmic fatalities were documented. Conclusions The HCQ/AZT combination therapy causes a significantly increase of QT interval compared to HCQ alone. Older patients under such regimen are at higher risk of experiencing QT prolongation. The use of such drugs may be considered as safe relating to arrhythmic risk in the treatment of COVID-19 patients as no arrhythmic fatalities occurred.

Ricci et al. Multimodality Imaging in Peripartum Cardiomyopathy KEY POINTS-Peripartum cardiomyopathy is a rare but potentially fatal disease requiring prompt identification and treatment. -Cardiac imaging plays a pivotal role for the diagnosis, risk stratification, and follow-up of peripartum cardiomyopathy and related complications. -Cardiovascular magnetic resonance is a high-throughput imaging modality providing relevant information for clinical decision-making and understanding of the pathophysiology underlying peripartum cardiomyopathy.

Background: There is no consensus on the benefit of red blood cell (RBC) transfusion after transcatheter aortic valve replacement. Methods: The multicenter Transfusion Requirements in Transcatheter Aortic Valve Implantation (TRITAVI) registry retrospectively included patients after transfemoral transcatheter aortic valve replacement; propensity score-matching identified pairs of patients with and without RBC transfusion. The primary end point was 30-day mortality; nonfatal myocardial infarction, cerebrovascular accident, and stage 2 to 3 acute kidney injury at 30 days were secondary end points. We repeated propensity score-matching according to the hemoglobin nadir, hemoglobin drop, and in the subgroup of uncomplicated patients, without major vascular complications or major bleeding. Results: Among 2587 patients, RBC transfusion was administered in 421 cases (16%). The primary end point occurred in 104 (4.0%) patients, myocardial infarction in 9 (0.4%), cerebrovascular accident in 38 (1.5%), and acute kidney injury in 125 (4.8%) cases. In the 842 propensity-matched patients, RBC transfusion was associated with increased mortality (hazard ratio, 2.07 [95% CI, 1.06–4.05]; P =0.034) and acute kidney injury (hazard ratio, 4.35 [95% CI, 2.21–8.55]; P <0.001). Interaction testing between RBC transfusion and mortality was not statistically significant in the above-mentioned subgroups, and such association was not documented in the corresponding propensity score-matched cohorts. In the multivariable Cox proportional hazards regression model, major vascular complications ( P =0.044), major bleeding ( P =0.041), and RBC transfusion ( P =0.048) were independent correlates of 30-day mortality. Conclusions: RBC transfusion correlates with increased mortality and acute kidney injury early after transcatheter aortic valve replacement and is an independent predictor of 30-day mortality, irrespective of periprocedural major bleeding and vascular complications. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03740425.