Magnetic resonance imaging in patients with sarcoidosis using parametric mapping

Sarcoidosis is a disease of uncertain origin that affects multiple systems, but especially the respiratory tract. The formation of granulomas is typical – therefore sarcoidosis is one of the granulomatous diseases. Granulomas are deposits in tissue in which cells of the immune system respond to a hitherto unknown stimulus. Sarcoidosis more often affects women than men, in a ratio of 1.5–2.0: 1. Cardiac sarcoidosis is clinically rare, probably affecting less than 5% of patients (although according to some studies up to 40% of patients), yet it is one of the most serious forms of the disease because it causes arrhythmias, which can result in sudden death.

Researchers from the Cardiovascular Magnetic Resonance Research team of the International Clinical Research Center of St. Anne’s University Hospital Brno (FNUSA-ICRC) in their study entitled “Myocardial T1 mapping using SMART1Map and MOLLI mapping in asymptomatic patients with recently diagnosed extracardiac sarcoidosis” focused on whether magnetic resonance imaging could detect cardiac involvement in time.

One hundred and twenty patients with a recently diagnosed extracardiac sarcoidosis and no history of heart disease were included in the study – one hundred and thirteen of them underwent CMR examination. The mean time since diagnosis of sarcoidosis was 0.8 (0.2-3.3) years. “T1 mapping is a relatively new cardiac magnetic resonance imaging technique, which allows data on T1 relaxation time and extracellular volume (ECV) of the myocardium, which are characteristics that should be affected by the possible occurrence of granulomas in the myocardium,” said doc. MUDr. Roman Panovský Ph.D., head of the research team.

The results of the study, contrary to expectations, showed that asymptomatic patients with extracardiac sarcoidosis showed no evidence of cardiac involvement using standard parameters assessing overall and regional left ventricular function. In addition, no prolongation of native myocardial T1 relaxation times was found and the ECV value was not increased. The study shows that in the early stages, sarcoidosis may not affect the heart at all, probably affecting the myocardium later, with some latency. The study was published in NMR in Biomedicine (IF 3.2).