ECG Case 008

70-year old patient presenting with severe chest pain, diaphoresis and syncope. BP 65/40.

Describe and interpret this ECG

ECG ANSWER and INTERPRETATION

Main Abnormalities

Widespread ST depression affecting multiple precordial (V2-6) and limb leads (esp. I, II, avF).
To some extent this is masked by an indistinct J point, upsloping (rather than horizontal) ST depression and some baseline wander of the ECG.
There is~3 mm ST elevation in aVR.

ST depression in aVF relative to the T-P baseline

ST depression in aVF relative to the T-P baseline.
The blue arrow denotes the approximate position of the J point.

ST elevation in aVR

Diagnosis

In the context of ischaemic chest pain and cardiogenic shock, the combination of…

Widespread ST depression
ST elevation in aVR > 1 mm
ST elevation in aVR > V1

… is extremely concerning for left main coronary artery (LMCA) occlusion.

However, this pattern is not entirely specific for LMCA occlusion. It may be seen whenever there is diffuse severe subendocardial ischaemia, e.g.

Severe triple vessel disease
Severe anaemia or hypoxaemia
Following resuscitation from cardiac arrest

This patient developed progressive cardiogenic shock complicated by runs of ventricular tachycardia. He was taken for immediate angiography where he was found to have a complete ostial occlusion of his left main coronary artery.

CLINICAL PEARLS

A similar ECG pattern of diffuse ST depression with ST elevation in aVR may also be seen with supraventricular tachycardias (AVNRT / atrial flutter).

This rate-related change is usually benign and resolves with resolution of the SVT.