The perpetual sword of Damocles: Cardiac involvement in systemic sclerosis and the role of non-invasive imaging modalities in medical decision making

Cardiac involvement in systemic sclerosis (SSc-CI) may be either primary or secondary to pathologic processes in other organs. In contrast to other autoimmune rheumatic diseases, primary SSc-CI preferentially manifests as non-ischemic myocardial fibrosis, with or without myocardial inflammation and minimal involvement of epicardial coronary arteries. Recent developments in cardiovascular (CV) imaging modalities and their increasing availability necessitate the creation of concrete recommendations for use in SSc patients, based on the most recent scientific evidence. Echocardiography offers rapid, effective, multiparametric, and widely available imaging evaluation of SSc patients, owing to its ability to analyze both left and right chambers, as well as pulmonary hemodynamics. However, it is an operator- and acoustic window-dependent modality that cannot perform tissue characterization, which is crucial in these conditions. CV magnetic resonance in SSc patients can accurately evaluate biventricular volumes, ejection fractions, myocardial fibrosis load, and changes suggestive of myocarditis. T2 mapping is the best index of edema indicating acute myocardial inflammation, while late gadolinium enhancement is an index of replacement fibrosis. Extracellular volume fraction (ECV) is an indicator of diffuse myocardial fibrosis only in the absence of significant myocardial inflammation. However, if myocardial inflammation/fibrosis coexist, ECV reflects a combination of the two, but it cannot completely discriminate between them. SSc-CI hangs like the sword of Damocles over physicians managing SSc patients. A constructive partnership between the rheumatologist and the cardiologist is necessary to provide each SSc patient with a comprehensive screening protocol for early detection and treatment of cardiopulmonary pathologic processes.