Right-sided lead V4R

ECG leads / veins · V4R

V4 mirrored onto the right chest in the fifth intercostal space at the right midclavicular line; ST elevation of 1 mm here is the most sensitive ECG sign of right ventricular infarction and is transient, so record it early in every inferior STEMI.

Traced from the start

  1. Right (anterior) aortic sinus
  2. Right coronary artery
  3. Right (acute) marginal artery
  4. Right ventricular free wall
  5. Right-sided lead V4R

Detail

Territory
Right ventricular free wall (RCA)
Threshold
ST elevation of 1 mm in V4R; disappears within hours of onset

When it goes wrong

ST elevation in V4R in an inferior STEMI

RV infarction: fluid-load for hypotension, withhold nitrates, expect bradyarrhythmia and AV block

Practise this structure

1 question in the bank tagged Coronary Circulation.