ECG of the Enlarged Heart

The Cardiac Cycle

Know this

During examinationV follows S2 and should beVisible with elevated JVP

Mitral Regurg

Aortic Regurg

Mitral Stenosis

Aortic Stenosis

What are the features of this ECG

Relations of ECG leads

aVRRV

Characteristics of normal QRS complex

1. Width : 3 small squares or less2. In Lead V1, the depth of S wave is > than the

height of R wave3. In Lead V5,V6, the height of R wave is always

< 25mm4. In the left ventricular leads (V5, V6), presence

of a septal Q wave is normal

Features of Left Ventricular Hypertrophy

• Left axis deviation (look at inferior leads III or AVF)• Tall R waves in lateral LV leads (aVL, V, VI - but not

V/VI in a grossly enlarged heart)• Deep S in septal/RV leads

(III, V1 & V2)• Delayed intrinsicoid deflection

> 0.05s• Strain pattern• ST-T abnormalities

ESTES Criteria for LVH ("diagnostic", >5 points; "probable", 4 points)

+ECG Criteria Points

a.Voltage Criteria (any of): R or S in limb leads >20 mm b.S in V1 or V2 > 30 mm c.R in V5 or V6 >30 mm

3 points

ST-T Abnormalities:Without digitalisWith digitalis

3 points1 point

Left Atrial Enlargement in V1 3 points

Left axis deviation 2 points

QRS duration 0.09 sec 1 point

Delayed intrinsicoid deflection in V5 or V6 (>0.05 sec) 1 point

c.ESTES Criteria for LVH ("diagnostic", >5 points; "probable", 4 points)

Analyse Stephen’s ECG

RV Hypertrophy

• Right axis deviation• Tall R-waves in RV leads (look at aVR)• Deep S-waves in LV leads • ST-T changes