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Brugada syndrome (BrS) is a controversial disease whose pathophysiology is still far from being fully understood. Unlike other cardiological disorders, a definite etiology has not yet been established so that it could be summarized under two main chapters: "functional" or "organic", "repolarization" or "depolarization" disorder. Despite initial descriptions leaned towards the organic substrate and delayed depolarization features, functional and repolarization theories have attracted most of the Cardiological attention for many years. Data from electrocardiography, endocavitary tracings, electroanatomic mapping and histopathology, however, demonstrated that BrS is mainly characterized by structural myocardial changes mostly at the right ventricular outflow tract (RVOT), but also at the right ventricle (RV) and by delayed conduction at the same sites. Conduction disorders at different levels may also be present and identify patients at high risk for major arrhythmic events. The aim of the present review is to provide the current state of art of the pathophysiology of BrS, focusing on electro‐vectorcardiography and electrophysiological features, histopathology, echocardiography, and cardiac magnetic resonance imaging (CMRI). [ABSTRACT FROM AUTHOR]

Introduction: Lesion Index (LSI) has been developed to predict lesion efficacy during radiofrequency (RF) catheter ablation. However, its value in predicting lesions size has still to be established. The aim of our study was to assess the lesions size reproducibility for prespecified values of LSI reached during RF delivery in an in vivo beating heart. Methods: Ablation lesions were created with different values of LSI in seven domestic pigs by means of a contact force‐sensing catheter (TactiCathTM, Abbott). Lesions were identified during RF delivery by means of a three‐dimensional mapping system (EnSiteTM Precision, Abbott) and measured after heart explantation. Histology was carried out after gross examination on the first three lesions to confirm the accuracy of the macroscopic evaluation. Results: A total of 64 myocardial lesions were created. Thirty‐nine lesions were excluded from the analysis for the following reasons: histological confirmation of macroscopic lesion measurement (n = 3), transmurality (n = 24), unfavorable anatomic position (n = 10), not macroscopically identifiable (n = 2). In a final set of 25 nontransmural lesions, injury width and depth were, respectively, 4.6 ± 0.6 and 2.6 ± 0.8 mm for LSI = 4, 7.3 ± 0.8 and 4.7 ± 0.6 mm for LSI = 5, and 8.6 ± 1.2 and 7.2 ± 1.1 mm for LSI = 6. A strong linear correlation was observed between LSI and lesion width (r =.87, p <.00001) and depth (r =.89, p <.00001). Multiple linear regression analysis identified LSI as the only ablation parameter that significantly predicted lesion width (p <.001) and depth (p <.001). Conclusion: In our in vivo study, LSI proved highly predictive of lesion size and depth. [ABSTRACT FROM AUTHOR]

Background: Catheter‐delivered radiofrequency (RF) lesion formation is a complex phenomenon, and few studies have explored the effect of catheter orientation on lesion size and catheter orientation behavior during pulmonary vein isolation (PVI) procedures. We evaluated the influence of catheter orientation on lesion dimensions in an in vitro experimental setting and investigated the catheter orientation behavior during PVI. Methods and results: 72 lesions were created in vitro on a porcine heart using a contact force catheter in a parallel, oblique, and perpendicular tip to tissue orientation. The superficial lesion length (SLL) increased shifting the catheter from perpendicular to parallel orientation. The intratissue absolute maximal lesion length (AML) was greater with an oblique catheter orientation. The lesion depth (LD) and the superficial lesion width (SLW) resulted similar with any orientation. Data from 21 PVI procedures in patients with paroxysmal atrial fibrillation using the "wide antral circumferential RF ablation" (WACA) technique were retrospectively analyzed. The mean contact angle among 1130 RF lesions was 28 ± 20°. A prevalent parallel orientation was noted in the anterior WACA segments, whereas it resulted more perpendicular in the posterior segments. Significant differences in catheter orientation between the three operators were found only in few WACA segments. Conclusions: In an in vitro setting, catheter orientation affects SLL and AML, but not LD and SLW. During PVI procedures, catheter orientation resulted mostly parallel to the endocardium. Catheter orientation varied among different WACA segments, but only small differences were found between three operators when considering similar WACA segments. [ABSTRACT FROM AUTHOR]

The article presents a case study related to 65-year-old man with severe ischemic cardiomyopathy and narrow QRS underwent prophylactic single-chamber internal cardioverter-defibrillator implant with the VDD active-fixation single-coil dedicated bipolar ventricular lead in a right ventricular mid septal position. Topics icnlude the significant decrease in R-wave amplitude has noticed during a routine remote monitoring session, and the chest X-ray has excluded lead dislocation or damage.

When performing epicardial ablation of ventricular tachycardia (VT), caution must be taken not to damage the coronary arteries. We report a case in which a new, nonfluoroscopic technique for incorporating an accurate, real-time reconstruction of the main coronary vessels into a three-dimensional electroanatomic map was used for epicardial VT ablation. [ABSTRACT FROM AUTHOR]