<unk>  Idiopathic<unk>  (formerly known as<unk>  Rheumatoid<unk>  (JIA), as defined by the American Rheumatism Association (ARA), is the presence of<unk>  (chronic, seronegative, and peripheral) before age 16 years, of at least 3 months duration, when other causes have been excluded. Chest pain, chest discomfort and dyspnea may found in polyarticular and systemic onset forms.  
Cardiac involvements are usually subclinical with early diastolic dysfunction followed by latent onset of symptoms with increasing systolic dysfunction and heart failure which is a late finding. Abnormal diastolic function of the left ventricle has also been reported in<unk>  idiopathic<unk>     
When occurs, cardiac involvement is the second major cause of mortality in<unk>  Idiopathic<unk> .
Cardiac involvement occurs in about 4.7% of all cases  and includes pericarditis, aortitis, coronary vasculitis, valvulitis (endocarditis), conduction system involvement, pulmonary hypertension and myocarditis.
Cardiac involvements may be seen due to disease progression and applied medical treatment. It has been shown that the cause of abnormal diastolic parameters may be multiple and may be a cumulative effect of several factors such as pericarditis with or without pericardial effusion, hypertension, left ventricular hypertrophy, therapy with cardiotoxic agents such as cyclosporine, gold salts d-penicillamine  chloroquine   and hydroxychloroquine, hypertension due to steroid therapy, secondary amyloidosis and vascular stiffness from vasculitis.
The heart in juvenile rheumatoid arthritis
The heart in rheumatoid arthritis
The heart in progressive systemic sclerosis 
The heart in Behçet's disease
The heart in psoriasis
The heart in Grave's disease 
The heart in Wegener's granulomatosis
The heart in essential mixed cryoglobulinemia