Congestive heart failure, or simply heart failure, is progressive and should not be confused with a heart attack, which involves sudden tissue death of the heart muscle. Although heart failure may occur suddenly in some cases, gradual loss of function is more common.
I believe SI it stands for: Sacroiliac Joint Injections Sacroiliac (SI) joint injections are commonly used to determine what is causing back pain. SI joint injections are primarily diagnostic injections, meaning that they help your doctor determine the cause of your back pain but may not provide you with any long-term relief from the pain.
the units of measurement generally accepted for all scientific and technical uses; together they make up the International System of Units. (See also metric system.) The abbreviation SI, from the French SystÃ¨me International d'UnitÃ©s, is used in all languages. There are seven base SI units, defined by specified physical measurements, and two supplementary units. Units are derived for any other physical quantities by multiplication and division of the base and supplementary units. The derived units with special names are shown in the accompanying table.