Paradoxical effect of ajmaline in a patient with Brugada syndrome

The typical Brugada ECG pattern consists of a prominent J-wave associated with ST-segment elevation localized in the right precordial leads V1-V3. In many patients, the ECG presents periods of transient normalization and the Brugada-phenotype can be unmasked by the administration of class-I antiarrhythmics. Reports have documented the heterogeneity of the Brugada syndrome ECG-phenotype characterized by unusual localization of the ECG abnormalities in the inferior leads. Case report A 51-year-old man, without detectable structural heart disease, was referred to us because of a history of syncope, dizziness, and palpitations. The ECG showed a J-wave and ST-segment elevation in the right precordial leads, suggesting Brugada syndrome. As other causes of the ECG abnormalities were excluded, the patient underwent an electrophysiological study that documented easy induction of ventricular fibrillation. During infusion of ajmaline, new prominent J-waves and ST-segment elevation appeared in the inferior leads, whereas the basal ECG abnormalities in the right precordial leads normalized. After infusion of isoprenaline, the ECG-pattern resumed the typical Brugada pattern. An implantable cardioverter-defibrillator was recommended.

In our patient, the double localization of the typical Brugada-pattern and the paradoxical effect of ajmaline on the ECG abnormalities confirmed the possibility of a phenotype heterogeneity in the Brugada syndrome.