In adults, three conditions are known to cause aortic stenosis. 1  Progressive wear and tear of a bicuspid valve present since birth (congenital). 2  Wear and tear of the aortic valve in the elderly. 3  Scarring of the aortic valve due to rheumatic fever as a child or young adult.ver time, excessive wear and tear leads to calcification, scarring, and reduced mobility of the valve leaflets. About 10% of bicuspid valves become significantly narrowed, resulting in the symptoms and heart problems of aortic stenosis.
Comma Splice Example. Comma splice is a common mistake made by most people who write in the English language. Here, we try to understand what a comma splice is with the help of a few examples. Take a look.
Comma Splice A comma splice is the use of a comma between two independent clauses. You can usually fix the error by changing the comma to a. period and therefore making the two clauses into two separate sentences, by changing the comma to a semicolon, or by making one clause.