Define the fourth heart sound. It is heard right before S1 late in diastole and sounds like ventricular filling. Sounds like da LUB-dub. It can be heard on the apex in the left lateral position. It is normal in people over the age of 40-50. Usually heard after exercise with no CV disease. Abnormal sounds like an atrial gallop.
Define subset. subset synonyms, subset pronunciation, subset translation, English dictionary definition of subset. n. A set contained within a set. n 1. maths a. a set the members of which are all members of some given class: A is a subset of B is usually written AâB b.... Subset - definition of subset by The Free Dictionary
A set in math is a group of items. It can be a group of numbers, variables, or anything else you can think of. When two or more groups have an item or items in common, the subset of items they have in common is what we call the intersection of sets. For example, let's say we had two different sets of numbers.