Background There is limited information on ethnic differences between patients with Brugada syndrome (BrS) with arrhythmic events (AEs). Objectives To compare clinical, electrocardiographic (ECG), electrophysiologic (EP) and genetic characteristics between White and Asian BrS-patients with AE. Methods SABRUS is a multicenter survey from Western and Asian countries, gathering 678 BrSpatients with first documented AE. After excluding patients with other (n=14; 2.1%) or unknown (n=30; 4.4%) ethnicity, 364 (53.7%) Whites and 270 (39.8%) Asians comprised the study group. Results There was no difference in AE age onset (41.3±16.1 years in Whites vs. 43.3±12.3 years in Asians, P=0.285). Higher proportions of Whites were observed in pediatric and elderly populations. Asians were predominantly males (98.1% vs. 85.7% in Whites, P<0.001) and frequently presented with aborted cardiac arrest (ACA) (71.1% vs. 56%, P<0.001). Asians tended to display more spontaneous type 1 BrS-ECG (71.5% vs. 64.3%, P=0.068). Family history of sudden cardiac death (FHSCD) was noted more in Whites (29.1% vs. 11.5%, P<0.001), with higher rate of SCN5A mutation carriers (40.1% vs. 13.2% in Asians, P<0.001), as well as more fever-related AEs (8.5% vs. 2.9%, 0.011). No difference was observed between the two groups regarding prior history of syncope and ventricular arrhythmia inducibility. Conclusions There are important differences between Asian and White BrS-patients. Asian patients present almost exclusively as male adults, more often with ACA and spontaneous type 1 BrS-ECG. However, they have less FHSCD and markedly lower SCN5A mutation rates. The striking difference in SCN5A mutation rates should be tested in future studies.

A 10.1 inch SVGA reflective type flexible active matrix electrophoretic displays were successfully fabricated on a thin metal foil substrate. It was developed a new multi‐barrier structure in order to use a rough metal foil as display substrate and designed a new TFT array structure for obtaining good performance. The backplane comprises a‐Si thin film transistor array fabricated using a conventional TFT manufacturing technologies. The 800×600 pixel display can be driven during extremely bending and measures only 0.3 mm in total thickness and weighs 32.8 grams. This prototype displays have a true paper‐like look and feel, with wide‐viewing angle and high contrast ratio.

A 62-year-old woman with a history of a paroxysmal supraventricular tachycardia (SVT) underwent catheter ablation. The baseline atrio-His and His-ventricular interval measurement were 112 and 48 ms, respectively. A dual antegrade atrioventricular nodal (AVN) physiology was observed during programmed atrial stimulation. The ventriculoatrial conduction was decremental and concentric, and the earliest atrial activation was recorded on the right atrial anteroseptum. Her clinical tachycardia was induced by programmed atrial stimulation and the atrial activation sequence during the tachycardia was the same as that during ventricular pacing. A single premature right ventricular stimulus delivered when the His was refractory and failed to affect the tachycardia. During right ventricular entrainment pacing, tachycardia resetting occurred after a stable fully paced QRS morphology, and the difference between the postpacing interval and tachycardia cycle length from the right ventricular apex was 205 ms. A single premature atrial contractions (PACs) with different coupling intervals were delivered via the proximal coronary sinus electrode until the tachycardia was terminated. A PAC delivered right before the His signal advanced the next (2nd) His by 20 ms without altering the immediate (1st) His and atrial signals in the His electrogram ( Figure 1A). However, a PAC delivered about 70 ms before the His signal advanced the 3rd His by 19 ms without affecting the immediate (1st) and next (2nd) His timings.The response of the SVT to the single PAC is shown in Figure 1B. Based on these electrophysiological findings, what is the possible mechanism of this unusual response of the SVT to the PAC? 2 DISCUSSION Padanilam et al. have reported the method to distinguish AVN reentrant tachycardia (AVNRT) from junctional tachycardia (JT). 1 They demonstrated the significantly different responses to PACs during the tachycardia. Any perturbation of the next His and atrial activations by a PAC delivered during His refractoriness is considered to indicate AVNRT. On the other hand, advancement of the immediate His without termination of the tachycardia by an earlier PAC is suggestive of JT. However, there may be exceptions, such as that when advancement of the immediate His by an earlier PAC without termination of the AVNRT due to dual ventricular responses occurs or when a JT with a dual AVN physiology advances the next His by a PAC timed during His refractoriness.Our case differed from those scenarios. When a later PAC was delivered during His refractoriness, the typical response of AVNRT was shown. However, with a relatively earlier PAC, the unusual response, which was not expected with either AVNRT or JT, was demonstrated.The possible mechanism is depicted as a ladder diagram in Figure 2. A PAC delivered about 70 ms before the His signal (red arrow) captured the atrial electrogram antidromically in the His electrogram, and rendered the fast pathway refractory preventing the previous slow pathway (SP) conduction from coming up from the lower ...

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Effective ablation approach for persistent atrial fibrillation (PeAF) beyond pulmonary vein (PV) isolation is still controversial. We developed a real-time computational AF modeling technique to perform rapid rotor mapping reflecting the individual electrophysiology and AF mechanisms. In this study, we investigated whether extra-PV ablation targeting a high maximal slope of the action potential duration restitution curve (Smax) improves the outcome of PeAF ablation. However, virtual ablation-guided Smax modulation approach for PeAF did not result in an improved procedural outcome compared to the empirical ablation strategy. Further investigation is needed regarding a more effective patient-customized mechanism-based AF catheter ablation using the functional electrophysiology.