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.
Summer classes can be between 3 and 11 weeks, depending on the colleg â¦ e and the subject. Semesters are about 4 months in duration. The fall semester is from late August or early September to December; the spring semester is usually from January to late April or early May.