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.
Notice the comma in the final example. You should always have a comma before FANBOYS that join two independent clauses (two subjects and two verbs that make up two complete thoughts). Look carefully at the next two sentences to see two independent clauses separated by comma + FANBOYS.