Unexpected Profound Transient Anterior ST Elevation After Occlusion of the Conus Branch of the Right Coronary Artery During Angioplasty
A 71-year-old male smoker presented with chest pain. The admission ECG showed transient lateral ST elevation that resolved before thrombolysis could be given. Coronary angiography revealed a severe proximal and a further midvessel stenosis in the right coronary artery (RCA; Figure, A). There was no obstructive disease in the left coronary artery. The midvessel RCA lesion was stented uneventfully. A second overlapping stent was then deployed to cover the proximal stenosis. The conus branch was occluded as a result of this stent (white arrow in panel B of the Figure), whereas the right ventricular branch remained patent (black arrow in panel B of the Figure). The patient developed chest pain immediately, and the ECG showed marked ST elevation in V1 through V3 (Figure, C). The left coronary artery remained unobstructed (Figure, D). The ECG changes resolved within 15 minutes. Creatinine kinase was 175 IU/L 1 hour after the procedure (reference: 25 to 195 IU/L) and 307 IU/L the next morning. Anterior ST elevation due to occlusion of a right ventricular RCA branch has been reported previously and is thought to be a mirror image of right ventricular ischemia. This is a profound example of this phenomenon, caused by acute conus branch occlusion.