It is difficult to determine end stage, but generally it involves pulmonary edema (fluids in the lungs), shortness of breath with very little exertion. Often the heart's left ventricle enlarges and that can/will cause arrhythmia and cardiac arrest. At the present time your mother has a strong contractility of the left ventricle that pumps 65% of the filling capacity....it appears from the enlarged right ventricle, etc. that your mother may have right side failure which means although there is good pumping contractility the right side is not pumping enough blood to lungs and therefore there is less filling prior to pumping and the system is not getting a very good supply of blood and that can explain shortness of breath, etc.