Tumor necrosis factor alpha (TNF-alpha) plays an important role in the pathogenesis of chronic inflammatory diseases, i.e., rheumatoid arthritis (RA), ankylosing spondylitis (AS), Crohn's disease (CD), and ulcerative colitis (UC). Anti-TNF-alpha strategies are successfully used in their treatment. However, their effect on heart function is still uncertain. The objectives of the study were to examine the acute and long-term effect of infliximab on the heart morphology and function in patients with chronic inflammatory disorders. Thirty-one patients (21 men and 10 women) were included. Ten percent of them were diagnosed with RA, 22.5 % with AS, 22.5 % with CD, and 45 % with UC, respectively. N-terminal fragment of pro-brain natriuretic peptide (NT-proBNP) was measured before and immediately after infliximab administration at the beginning of the study and in the sixth and 12th months. Echocardiography was performed at baseline and in the sixth and 12th months. There was a significant increase in NT-proBNP after the first infliximab infusion (88.40 ± 14.09 vs. 95.24 ± 14.28 pg/ml, p = 0.0046) and similar response was detected after each infusion in the sixth and 12th months. Plasma NT-proBNP slightly but not significantly decreased (88.40 ± 14.09 vs. 81.74 ± 23.14 pg/ml, p = 0.583, and 88.40 ± 14.09 vs. 56.83 ± 17.77 pg/ml, p = 0.0576, in the sixth and 12th months, respectively). There were no significant changes in echocardiographic structural and functional parameters of the left ventricle during follow-up. Plasma NT-proBNP mildly but significantly increases immediately after infliximab infusion. However, long-term infliximab administration does not deteriorate both cardiac morphology and function.