What is the difference between systolic and diastolic and it is chronically increased by arteriosclerosis?

Yes: Systolic blood pressure is the maximum blood pressure found during the cardiac cycle, while diastolic blood pressure is the minimum pressure that's found. The difference between the two is called the pulse pressure. A big component of how big the pulse pressure is is the stiffness of the arteries. So since arteriosclerosis is hardening of the arteries, this disease process increases pulse pressure.