Possible contribution of ischemia of the conus branch to induction or augmentation of Brugada type electrocardiographic changes in patients with coronary artery disease.

Recent evidence suggests an association between vasospastic angina and Brugada syndrome. Here we present two cases of coronary artery disease who presented with ECG abnormalities which might have been provoked or enhanced by ischemia of the conus branch of the right coronary artery. The 12-lead ECGs demonstrated normal sinus rhythm in these two cases. Interestingly, a saddle back or coved type ST segment elevation in leads V1-V3 was documented either in the percutaneous transluminal angioplasty procedure of the proximal right coronary artery or with an intracoronary acetylcholine (Ach) administration into the right coronary artery. These Brugada type ECG changes were restored to the baseline ECG waveform after improvement in the ischemia. In the second case, vasospasms of the conus branch of the right coronary artery were associated with a coved type ST segment elevation in leads V1 to V2. We discuss the possible interaction between ischemia caused by conus branch lesions and Brugada type electrocardiographic changes.