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.
si - international system of units The name SystÃ¨me International d'UnitÃ©s, (International System of Units) and the abbreviation SI, were established by the 11th General Conference on Weights and Measures (CGPM) in 1960. The base quantities used in the SI are length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity.