Rheumatic heart disease is the destruction of the heart valves and heart due to rheumatic fever. This damage can also affect the mitral valve or the aortic valve and create holes to leak and also it becomes narrow. Rheumatic fever occurs as a result of a rare strain of strep bacterial infection that isn’t treated or is inadequately treated with antibiotics. The main complications of rheumatic diseases include bacterial endocarditis, rupture heart valve, pregnancy delivery complications.