Background-Brugada syndrome is associated with a high risk of sudden cardiac death and is caused by mutations in the cardiac voltage-gated sodium channel gene. Previously, the R282H-SCN5A mutation in the sodium channel gene was identified in patients with Brugada syndrome. In a family carrying the R282H-SCN5A mutation, an asymptomatic individual had a common H558R-SCN5A polymorphism and the mutation on separate chromosomes. Therefore, we hypothesized that the polymorphism could rescue the mutation. Methods and Results-In heterologous cells, expression of the mutation alone did not produce sodium current. However, coexpressing the mutation with the polymorphism produced significantly greater current than coexpressing the mutant with the wild-type gene, demonstrating that the polymorphism rescues the mutation. Using immunocytochemistry, we demonstrated that the R282H-SCN5A construct can traffic to the cell membrane only in the presence of the H558R-SCN5A polymorphism. Using fluorescence resonance energy transfer and protein fragments centered on H558R-SCN5A, we demonstrated that cardiac sodium channels preferentially interact when the polymorphism is expressed on one protein but not the other. Conclusions-This study suggests a mechanism whereby the Brugada syndrome has incomplete penetrance. More importantly, this study suggests that genetic polymorphisms may be a potential target for future therapies aimed at rescuing specific dysfunctional protein channels. (Circulation. 2006;114:368-376.)

No abstract

In accordance with the electrophysiological background, the typical ECG pattern of Brugada syndrome is also characterized by a considerable prolongation of the QT interval in right precordial leads.

AimsIn patients with atrial fibrillation (AF) pharmacological or electrical cardioversion may be performed to restore sinus rhythm. The procedure is associated with an increased risk of thromboembolic events, which can be significantly reduced by adequate anticoagulation (OAC). Our aim was to create a partly prospective, partly retrospective cardioversion registry, particularly focusing on OAC strategies in different European countries, and on emerging choice of OAC over time.MethodsFrom September 2014 to October 2015, cardioversions due to AF performed in six European city hospitals in five European countries (Hungary: Budapest-1 and -2; Italy: Bari and Pisa; France: Amiens; Spain: Madrid; and Lithuania: Kaunas) were recorded in the registry.ResultsA total of 1101 patients (retrospective/prospective: 679/422, male/female: 742/359, mean age: 67.3 years ± 11.2) were registered. Most of the cardioversions were electrical (97%). Oral anticoagulants were administered in 87% of the patient, the usage of non-VKA oral anticoagulants (NOACs) vs Vitamin K antagonists (VKA) was 31.5% vs 68.5%, respectively. Seventy seven percent of the patients were given oral anticoagulants more than 3 weeks prior to the procedure, and 86% more than 4 weeks after the procedure. When using VKA, international normalized ratio (INR) at cardioversion was above 2.0 in 76% of the cases. A decline in VKA usage (P = 0.033) in elective cardioversion over approximately 1 year was observed. During the observation period, there was an increase in apixaban (P < 0.001), a slight increase in rivaroxaban (P = 0.028) and no changes in dabigatran (P = 0.34) usage for elective cardioversion. There were differences in use of OAC between the countries: Spain used most VKA (89%), while France used least VKA (39%, P < 0.001).ConclusionAccording to current AF guidelines, NOACs are adequate alternatives to VKA for thromboembolic prevention in AF patients undergoing elective cardioversion. Our results indicate that NOAC use is increasing and there is a significant decrease in VKA use.

We report the case of an 86-year-old man referred for abdominal pain and ECG signs of inferior myocardial infarction. Transthoracic, transoesophageal and contrast echocardiographs showed a septal intra-mural haematoma, dissecting the right ventricle wall and partially obliterating the right ventricle lumen. A patent communication with left ventricle with extensive wall thrombosis was present at Doppler examination within dissecting haematoma. Although the patient refused any surgical treatment, a 3-month follow-up was uneventful.