Ischemia-induced Brugada-type ST-segment alternans and Brugada syndrome.
The mechanisms of Brugada-type electrocardiographic (ECG) pattern remain unclear.


METHODS
The ST-segment was evaluated during coronary intervention of proximal right coronary artery (RCA). We measured ST-segment elevation with a drug challenge test with a sodium channel blocker. The ST-segment changes were compared with those in true Brugada syndrome.


RESULTS
Brugada-type ECG was observed in 6 patients but not in 9 patients during coronary intervention. Five patients demonstrated Brugada-type ST elevation and alternans from coved type to saddleback type during coronary intervention. The patients with ST alternans demonstrated the conus branch occlusion or RV branch occlusion. A drug challenge test developed a significant ST-segment elevation neither in patients with Brugada-type ECG nor in patients without Brugada-type ECG. (0.69±0.48 mv vs. 0.48±0.31 mv, p=NS) There was a significant difference in the ST-segment elevation between patients with Brugada-type ECG during the coronary intervention and patients with true Brugada syndrome (n=5). (0.69±0.48 mv vs. 2.86±0.61 mv, p<0.05).


CONCLUSIONS
Ischemia of proximal RCA can masquerade as the Brugada syndrome, ST-segment elevation and alternans. Ischemia of proximal RCA could be one of the different entities showing Brugada-type ECG from true Brugada syndrome.
Chikaya
C
Omichi
Naoki
N
Fujimoto
Atsushi
A
Kawasaki
Atsunobu
A
Kasai
D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000379:methods; D053840:Brugada Syndrome / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology; D002037:Bundle-Branch Block / Q000175:diagnosis / Q000209:etiology; D003324:Coronary Artery Disease / Q000628:therapy; D003937:Diagnosis, Differential; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008012:Lidocaine / Q000031:analogs & derivatives; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications* / Q000175:diagnosis* / Q000503:physiopathology; D011446:Prospective Studies; D026941:Sodium Channel Blockers
D026941:Sodium Channel Blockers; D008012:Lidocaine; C042288:pilsicainide