Definition of primary and secondary amenorrhea. Amenorrhea is the medical term for the absence of menstrual periods, either on a permanent or temporary basis. Amenorrhea can be classified as primary or secondary.
Most inherited bleeding disorders are the result of abnormal platelet function or a deficiency in one or more of the factors involved in the blood clotting system. The most serious and common inherited coagulation disorders in dogs are hemophilia(deficiency of factor VIII or IX) and von Willebrand's disease (lack of von Willebrand factor). Other coagulation disorders are discussed here.
The most common cause of an acquired heart murmur in the dog is 'mitral insufficiency' (also called 'mitral regurgitation'), a condition in which the mitral valve becomes thickened and begins leaking (see our handout 'Mitral Valve Disease in Dogs') - mitral insufficiency tends to be more common in small breed dogs.