Immunological aspects of cardiac disease

Introduction Although the vast majority of cardiac diseases relate to the presence of atherosclerosis in the vessels supplying blood and oxygen to the heart, there are certain conditions in which immunological events play an important role. This chapter will concentrate on the immunological aspects of these diseases. We will also discuss the animal models associated with each of these disorders with particular emphasis on whether these models help us to understand further the immunological aspects of these conditions. Acute rheumatic fever (ARF) is a delayed, nonsuppurative sequela of a pharyngeal infection with the group A streptococcus. A latent period of two to three weeks follows the initial streptococcal pharyngitis. The latent period remains the same for each individual patient in the event of a recurrence. This suggests that the patient has already been exposed to more than one streptococcal infection in the past. The onset of disease is usually characterized by an acute febrile illness, which may manifest itself in one of three classical ways: (1) The patient may present with migratory arthritis predominantly involving the large joints of the body. (2) There may also be concomitant clinical and laboratory signs of carditis and valvulitis, or carditis and valvulitis may be the only signs of an acute episode. (3) There may be involvement of the central nervous system, manifesting itself as Sydenham's chorea. The clinical episodes are self-limiting but damage to the valves may be chronic and progressive, resulting in cardiac decompensation and death.