Authors

• Vedran Velagić — University of Zagreb School of Medicine, University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0001-5425-5840
• Davor Puljević — University of Zagreb School of Medicine, University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0003-3603-2242
• Mislav Puljević — University of Zagreb School of Medicine, University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0003-1477-2581
• Borka Pezo-Nikolić — University of Zagreb School of Medicine, University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0002-0504-5238
• Davor Miličić — University of Zagreb School of Medicine, University Hospital Centre Zagreb, Zagreb, Croatia — ORCID: 0000-0001-9101-1570

Keywords

Brugada syndrome, ajmaline test, implantable cardioverter defibrillator

DOI

Full Text

**Introduction**: Brugada syndrome (BS) is a genetic disease characterized by typical changes in the ECG and an increased risk of sudden cardiac death (SCD). Sodium channel blockers may unmask disease by inducing a typical Brugada type I pattern in the ECG (1, 2). Until recently, ajmaline was not available in the Republic of Croatia and ajmaline testing was not routinely conducted. **Methods:** From December 2015 ajmaline is available at University Hospital Centre Zagreb. Ajmalin test was indicated for individuals with a family history of SCD or unexplained syncope with type 2 Brugada pattern, or the family members of discovered proband. Testing was conducted in electrophysiologic (EP) lab using “EP Medsystems” hardware. Standard ECG settings were applied (25 mm/s, 1 mV/1 cm). In addition to standard precordial leads, V1 and V2 were recorded in the third intercostal space. Ajmaline was applied in a dose of 1 mg/kg within 5 minutes. After recording the basic ECG, traces were recorded at 0.7 mg/kg (3 min), 1 mg/kg (5 min) and washout (2 min after the administration). Test was defined as positive when a typical type I morphology in V1 or V2 leads with ST elevation of ≥2 mm occurred (3). In case of a positive test EP study was performed. **Results:** The study included 14 patients (7 men, mean age 35.9±15.7 years). Five of the 14 tests were positive (35.7%). Four BS probands were discovered, and one family member tested positive. Eight (57.1%) individuals were tested as family screening. In one of the 5 ajmaline positive patients (20%) EP study was positive, while 3 out of 5 (60%) patients positive BS received an implantable cardioverter defibrillator (ICD). Unexplained syncope or positive EP study alongside with positive ajmaline test indicated ICD implantation. One patient (33%) received inadequate ICD shock, due to a previously unrecognized atrial fibrillation with a rapid ventricular response. **Conclusion:** Brugada syndrome is an important cause of sudden cardiac death in patients with structurally normal heart. Ajmalin test allows detection of the disease and prevention of SCD in otherwise young healthy individuals. In addition to avoiding certain drugs, implantation of an ICD is a key part of the treatment of this syndrome.

Literature

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