Right ventricular infarction
See brief interpretation of 12 lead EKG above
- ST segment elevation (≥ 0.1 mV) in lead II, III and aVF (inferior leads)
- co-existent ST segment elevation in lead V1 suggests right ventricular involvement
- pathological Q waves formation in inferior leads
- reciprocal ST segment depression in lead I and aVL
- first degree heart block (PR prolongation > 0.22 sec)
As the treatment of right ventricular infarction differs from that of left ventricular infarction it is important to recognize. Right ventricular involvement should always be considered when inferior myocardial infarction is present.
Besides ST segment elevation in inferior leads the standard 12 lead EKG may show ST segment elevation in lead V1, which is “looking” at the anterior wall of the right ventricle.
However standard 12 lead EKG in general is insensitive in diagnosing right ventricular infarction. Right sided chest leads should be obtained and examined for ST segment elevation. The leads are placed like the standard precordial leads – just on the right chest side.
In particular ST segment elevation ≥ 0.1 mV in lead V4R (“R” for “right”) is considered sensitive for right ventricular involvement.
As to the 12 lead EKG above no right sided leads were obtained. A coronary arteriography revealed occlusion of the proximal right coronary artery (RCA) and an echocardiography performed later also indicated right ventricular involvement.
Clinically the patient with right ventricular infarction may present with the triad of distended neck veins, clear lung fields and hypotension. The hypotension may worsen if usual therapy with vasodilators are administered. Instead the patient may respond well to a fluid bolus.