What is the chance of me having a sudden cardiac arrest is aortic stenosis?

Low to slim: It will all depend on the severity of your stenosis. Mild and even moderate degrees of severity do not necessarily place you at a significantly higher risk but severe degrees may, particularly with vigorous exertion. You do need to check with your cardiologist who will probably want to perform an echocardiogram after exercise. It is important you know there are treatments available if necessary.

Depends: Severity of aortic stenosis impacts risk of cardiac arrest. Also coronary artery disease is also associated with aortic stenosis thus also increasing the risk of cardiac arrest. However for mild to moderate aortic stenosis the risk is ameliorated.