It is written that to get S4 sound we must have a hypertrophied, non compliant, non-dilated ventricle.
How can LV in aortic stenosis be hypertrophied but non-dilated? Isn’t hypertrophy the same as being dilated? Please explain
In AS the hypertrophy is concentric, leading to increased muscle mass but decreased chamber size
Dilatation means increase in chamber size and thinning of ventricular wall . Dilatation happen when heart chamber is continuously forced to accomodate excess amount of blood than normal status (increased preload states ) . Ultimately thinning of wall lead to systolic failure
Hypertrophy means increase in thickness of ventricular wall so increase in weight ( oftenly hypertrophy is associated with decrease in chamber size which can lead to diastolic failure ) to create excess pressure to pump blood out into aorta . Usually occur when heart chamber is forced to pump blood against high pressure like in Aortic stenosis