This ECG was obtained from a 78-year-old woman who had been experiencing intermittant chest pain for two days. When she finally presented to the Emergency Department, her ECG showed ST elevation in the inferior leads II, III, and aVF. She also has ST depression in I and aVL, which represents reciprocal changes seen in the high lateral leads, which are opposite the inferior wall. In addition, V1 and V2 show some ST depression, with early transition of the R waves (taller than normal for V2 and V3). This is a common finding in IWMI, and indicates posterior wall involvement. The injury is continuous from the inferior wall of the left ventricle, up the posterior wall, because both were supplied in this case by the right coronary artery.
This ECG has three rhythm strips. The more rhythm strips you have, the easier it is to determine the rhythm. In this case, the rhythm is normal sinus rhythm. But the extra rhythm strips would allow you to compare P wave morphology in three views if the rhythm was in question. Instructors: ask your students what they think about this rate (78 per minute) in the setting of acute M.I. Is it within normal range? Is it optimal for the injured heart? Another good point to bring up is the use of additional right-side leads to assess the right ventricle. V3R and V4R can be very useful in determining whether right ventricular M.I. is also present. Some practitioners skip this step and evaluate the RV using echocardiography. In the emergency setting, however, it can be very helpful to know the condition of the RV. RVMI is always a possiblity in RCA occlusion, and RVMI can increase mortality significantly. BP must be protected, since the injured right ventricle is very dependent on preload to function adequately as a pump, providing preload for the left side of the heart.
This patient was lost to followup.