THIS IS A NEW FRAME AND WILL REQUIRE A NEW GRAPHIC SHOWING THE 6 frontal plane LEADS (I-aVF) FROM FRAME 35 WITH LEADS I, II, III SEPARATED from LEADS aVR,L and F BY THE FRONTAL PLANE TRIAXIAL DISPLAY SHOWING THE ST SEGMENT VECTOR POINTING TO THE RIGHT AND INFERIORLY]
As discussed earlier in another patient with an inferior wall infarction (see page 8), there are additional clues in the standard 12 lead tracing suggesting the possibility of right ventricular involvement. This is the same tracing as that shown on the previous page. The greater ST segment elevation in lead III (4mm) than in lead II (2mm), coupled with the ST depression in leads I and aVL, indicates that the ST segment spatial vector is directed to the right as well as inferiorly. Its frontal plane axis is approximately +120 degrees. This suggests occlusion of the right rather than the circumflex coronary artery and raises the possibility of right sided involvement in the ischemia process.