Noninvasive Electrocardiographic Imaging Diagnosis of Brugada Syndrome

Maria Chaykovskaya1, Mikhail Chmelevsky1, Boris Rudic2, Erol Tueluemen2, Vitaly Kalinin3
1EP Solutions SA, 2Mannheim University Clinic, 3EP Solitions SA


Brugada syndrome (BrS) is a well-known inherited heart disease with a high risk of a sudden cardiac death. Thy only way to make a diagnosis is standard ECG. But what if diagnostic criteria are not fully met? These cases are called BrS-like ECGs. In our study we perform noninvasive electrocardiographic imaging (ECGI) in 10 patients with BrS-like ECGs. Method allows to reconstruct local unipolar electrogramms on heart surface noninvasively, using body surface mapping and heart/torso anatomy by CT or MRI scan. Standard algorithm for diagnosis verification includes drug test, aimed to unmask typical BrS ECG pattern of ST segment elevation > 2 mV following with negative T wave in one of right precordial leads. While standard ECG looks very similar in all 10 patients (ST segment elevation < 2 mV with a following negative T wave), morphology of local unipolar electrogramms in right ventricle outflow tract (RVOT) differ a lot. At baseline condition patients with verified BrS (positive drug test, n=5) have morphological anomalies inherent to BrS patients in RVOT – ST segment elevation >2 mV, fragmentation (more than three distinct peaks) and low voltage. Median (Me) of amplitude of ST segment elevation on the epicardium was 2,3 mV in BrS patients versus 0,1 mV in patients with negative drug test (p=0,008), and 2,6 mV vs 0,2 mV on endocardium. Fragmentation of electrogramms was registered in all BrS patients on the epicardial surface (n=5). The amplitude of electrogramms was lower on the epicardium surface in BrS patients Me=0,1 mV vs Me=3,6 mV in drug test negative patients, but the difference was not statistically significant. ECGI might be used as a single method for making a diagnosis of BrS in cases when standard ECG remains unclear.