Cardiac imaging techniques in systemic autoimmune diseases.
Systemic autoimmune disorders are frequently associated to cardiac involvement and to a high prevalence of ischemic coronary events, often occurring at a younger age than in the normal population. Large increase in mortality is related to premature atherosclerosis with coronary artery disease and stroke in patients with connective tissue diseases. Coronary heart disease is responsible for 40-50% of the deaths of patients with rheumatoid arthritis. Transesophageal or transthoracic echocardiography are the most useful and noninvasive techniques able to detect not only valvular abnormalities, embolic sources or pulmonary hypertension, but also left ventricular systolic or diastolic dysfunction. Furthermore, the introduction of new indexes, contrast agents and software increased the accuracy of this technique. It is possible now to evaluate coronary flow reserve by transthoracic echocardiography in patients with systemic autoimmune disease in order to detect microvasculature disorder. However, an ischemic response in a symptomatic patient requires, in most cases, further evaluation with cardiac catheterization. Coronary artery imaging allows confirmation of the presence, extent and position of atheromatous lesions. More recently, other imaging modalities including magnetic resonance and computerized tomography angiography have been developed to allow imaging of the coronary arteries.