ECG of the Enlarged Heart

The Cardiac Cycle

Know this During examination V follows S2 and should be Visible with elevated JVP

Mitral Regurg

Aortic Regurg

Mitral Stenosis

Aortic Stenosis

What are the features of this ECG

Relations of ECG leads aVR RV

Characteristics of normal QRS complex Width : 3 small squares or less In Lead V1, the depth of S wave is > than the height of R wave In Lead V5,V6, the height of R wave is always < 25mm 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 Voltage Criteria (any of): R or S in limb leads >20 mm S in V1 or V2 > 30 mm R in V5 or V6 >30 mm 3 points ST-T Abnormalities: Without digitalis With digitalis 3 points 1 point Left Atrial Enlargement in V1 Left axis deviation 2 points QRS duration 0.09 sec 1 point Delayed intrinsicoid deflection in V5 or V6 (>0.05 sec)

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