Aortic stenosis and exercise question?

[sameeralord]

In aortic stenosis there is ventricular hypertrophy and this could lead to reduced cardiac ooutput. My question is why is the ventricular hypertrophy in aortic stenosis, inferior to ventricular hypertrophy you get in exercise. Why is their better ventricular hypertrophy that increases cardiac output occurs, in exercise. Thanks

 

[SW VandeCarr]

In aortic stenosis there is ventricular hypertrophy and this could lead to reduced cardiac ooutput. My question is why is the ventricular hypertrophy in aortic stenosis, inferior to ventricular hypertrophy you get in exercise. Why is their better ventricular hypertrophy that increases cardiac output occurs, in exercise. Thanks

If you are talking about stenosis of the aortic valve itself, the ventricular hypertrophy is secondary to increased outflow resistance, and in this case, the pattern of hypertrophy may further interfere with outflow. There is also a rare condition called Idiopathic Hypertrophic Subaortic Stenosis (IHSS) where the cause is unknown and can been seen in infants.

With strenuous regular exercise, the hypertrophy is due to training and is symmetric. The outflow tract is normal.

As a result, with stenosis, the heart must work harder just to maintain the necessary cardiac output, while with training, cardiac performance is more efficient with substantial reserve for increased cardiac output when required.

 

[bobze]

If you are talking about stenosis of the aortic valve itself, the ventricular hypertrophy is secondary to increased outflow resistance, and in this case, the pattern of hypertrophy may further interfere with outflow. There is also a rare condition called Idiopathic Hypertrophic Subaortic Stenosis (IHSS) where the cause is unknown and can been seen in infants.

With strenuous regular exercise, the hypertrophy is due to training and is symmetric. The outflow tract is normal.

As a result, with stenosis, the heart must work harder just to maintain the necessary cardiac output, while with training, cardiac performance is more efficient with substantial reserve for increased cardiac output when required.

Exactly SW. It makes a difference in muscle whether hypertrophy is by parallel or series additions of muscle.

Also, hypertrophy from exercise is a global affair for the muscle involved. Sameeralord, when we talk about hypertrophy of only one ventricle because of pathology, then you are changing the anatomy of the heart. Which tends to displace the electrical axis of the heart in the direction of the hypertrophied ventricle and thus affects the QRS complex.