Chest pain is the most frequent symptom in people who have symptoms with mitral valve prolapse. The chest pain may be very bothersome and frightening, but it does not increase the risk of heart attack, death, or other heart problems. Mitral valve prolapse is the most common cause of mitral regurgitation. That's a condition in which some blood flows backward through the mitral valve with each heartbeat. Over years, moderate or severe mitral regurgitation can cause weakness of the heart muscle, known as congestive heart failure.
1 A trimester system divides the academic year into three terms which can be as short as eight weeks or as long as 16 weeks each. 2  A quarter system divides the academic year into four terms, up to 12 weeks each, and generally counts the summer as one of the terms. second term lasts from early September to late December with a two-week-long break for New Year's at the end of the year. The term is followed by a third term from early January to late March and a brief week-long spring break. The graduation ceremony occurs in March, and the enrollment ceremony in early April.
semester - one of two divisions of an academic year. trimester - one of three divisions of an academic year. quarter - one of four periods into which the school year is divided; the fall quarter ends at Christmas.