Background: Brugada syndrome (BrS) has diagnostic challenges and controversial risk assessment. We aimed to investigate invasive and non-invasive parameters in symptomatic and asymptomatic patients from a Brazilian cohort of type-1 BrS. Methods Patients with spontaneous and drug-induced type-1 BrS were classified in two groups, asymptomatic (n=116, 84.1%) and symptomatic (n=22, 15.9%, 13 with arrhythmogenic syncope, 9 with aborted sudden cardiac death). Genetic testing, EPS parameters, and ECG parameters were analysed. Results: 138 consecutive patients were eligible, 101 men (73.2%), mean 41.4 years, mostly probands (79%). Spontaneous pattern, observed in 77.5% of the patients, was associated to symptoms only if expressed in V1 and V2 standard position (not high precordial leads) (p=0.014). All symptomatic patients were probands. The presence of RV outflow tract conduction delay (RVOTcd) signs, positive EPS and SCN5A status was similar between symptomatic and asymptomatic subjects. During mean 75-month follow-up, 8 patients had appropriate therapies. All had spontaneous type-1 ECG pattern and 2/8 (25%) were asymptomatic, with positive EPS. The overall LAE incidence of 1.1%/year dropped to 0.27% in asymptomatic patients. RVOTcd occurred more frequently in SCN5A carriers (QRS-f 33.3% vs 7.7%, p=0.005; AVR sign 58.3% vs 13.6%, p<0.001; deep S in lead I 75% vs 48.5%, p=0.025%), as well as longer HV interval (66ms vs 49ms, p<0.001). Conclusions: Spontaneous type-1 Brugada pattern in standard leads and proband status were more frequent in symptomatic subjects. RVOTcd, more common in SCN5A carriers, did not predict symptoms in BrS patients. EPS exhibited limited prognostic value for this low risk population.

Introduction - Dental anesthetic management in ICD recipients with CCh can be challenging due to the potential risk of life-threatening arrhythmias and appropriate ICD therapies during procedural time. We assessed the hypothesis that the use of local dental anesthesia with 2% lidocaine with 1:100.000 epinephrine or without a vasoconstrictor can be safe in selected ICD and CCh patients, not resulting in life-threatening events. Methods and Results - Restorative dental treatment under local dental anesthesia was made in two sessions, with a wash-out period of 7 days (cross-over trial), conducting with a 28h - Holter monitoring, and 12-lead electrocardiography, digital sphygmomanometry, and anxiety scale assessments in 3 time periods. Ventricular/supraventricular arrhythmias frequency, device shocks, corrected QT interval and dynamic changes in right precordial leads in BrS were also analyzed. All patients were in stable condition with no recent events before the dental care. Twenty-four consecutive procedures were performed in 12 patients (9 women, 3 men) with CCh and ICD: 7 (58.3%) had LQTS, 4 (33.3%) had BrS and 1 (8.3%) had CPVT. Holter analysis did not demonstrated increased heart rate or sustained arrhythmias. Blood pressure, electrocardiographic changes and anxiety measurement showed no statistically significant differences. No life-threatening events occurred during dental treatment, regardless the type of anesthesia. Conclusions - Lidocaine administration, with or without epinephrine, can be safely used in selected CCh-ICD patients without life-threatening events, as long as the protocol is followed. These preliminary findings need to be confirmed in a larger population with ICD and CCh.