Blood leaks back into the chambers rather than flowing forward through the heart or into an artery. In the United States, backflow most often is due to prolapse. Prolapse is when the flaps of the valve flop or bulge back into an upper heart chamber during a heartbeat. Prolapse mainly affects the mitral valve.
NSTEMI is a shorthand medical term for non-ST segment elevation myocardial infarction. It is one type of myocardial infarction also called heart attack.
Between July 2008 and September 2009, data for 41 683 patients with NSTEMI and 27 860 patients with STEMI were captured at 309 US hospitals participating in the AR-G, a quality improvement registry of patients in the US with MI.