Non-Q Infarction

Report:

Sinus rhythm

ST/T changes consistent with infarction/ischæmia

Poor R wave progression

Comment:

This is the same patient whose stage of illusion is shown on the preceding page. Now, 24 hours later, the T waves have “flipped” and the cardiac enzymes showed a small but definite infarction. In the past, such a non-Q wave (or ST/T) infarction would have been called subendocardial. It is now known (or, rather, more widely known) that the distinction between transmural and subendocardial infarcts cannot be made electrocardiographically. Definition of myocardial infarction itself has changed71, but its ECG correlates remain the same. Not in name, inevitably. This is now ST segment elevation myocardial infarction72.

The computer picked a small R wave loss between V1 and V2, something I would have overlooked. Although this can be positional, in this case it probably wasn’t. Precordial R wave loss is a sign of myocardial infarction, as is a failure of R waves to grow from right to left, or of R/S ratio to increase. The term, poor R wave progression, is a timid way of saying anterior infarction, but it has its uses: there are other causes of poor R wave progression and there is some intellectual honesty in sticking with the purely descriptive name.

A day later still, the patient had another episode of chest pain, “normalising” the previously inverted T waves; thrombolysis was repeated, but the cardiac enzymes rose again and R wave almost disappeared in lead V2 (below, Fig 97a).

On Day 6, angiography was performed, showing 90% left anterior descending artery stenosis with 70% lesion in its first diagonal branch; the right coronary artery had only 50% stenosis. He was referred for a PTCA in Sydney: it was hoped that something could still be salvaged.

Both open heart surgery and PTCA came to Canberra (the Australian capital) later that year (1998).