ECG and Brief Discussion - Right Atrial Hypertrophy

ECG Criteria
• P - Tall, > 2.5 mm (> 2.5 small squares), better seen in LII, LIII, aVF and sometimes in V1 .
(Tall P is called P pulmonale).
• P in V1 - Biphasic, tall initial positive deflection (> 1.5 mm) with a small negative deflection (only positive deflection may be present).

Q. What does P pulmonale indicate?
Ans. It indicates right atrial hypertrophy or enlargement.
(It is called P pulmonale, because it is commonly seen in severe pulmonary disease).

Q. What are the causes of P pulmonale?
Ans. As follows:

• COPD with chronic cor pulmonale (commonest).
• ASD.
• Tricuspid regurgitation or stenosis.
• Pulmonary stenosis.
• Pulmonary hypertension (due to any cause).
• Transient P pulmonale occurs in acute pulmonary embolism and acute severe asthma.