We always look at the thickness of Inter ventricular septum for LVH . The Normal IVS thickness is up to 11 mm in diastole . LVH is definite if IVS measure > 11 mm .It is certain if it is > 12mm . But , we need to realise LVH by definition is not simply wall thickness .
It is increased LV mass .
LV mass can increase without wall thickening . This is referred to eccentric LVH . For example in chronic volume overload states (or even DCMs ) LV mass may increase without septal thickneing .