This Article Full Text Full Text (PDF) All Versions of this Article: 93/4/1351    most recent Author Manuscript (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Pingitore, A. Articles by Iervasi, G. Search for Related Content PubMed PubMed Citation Articles by Pingitore, A. Articles by Iervasi, G. Related Collections Thyroid Cardiovascular Endocrinology

Acute Effects of Triiodothyronine (T₃) Replacement Therapy in Patients with Chronic Heart Failure and Low-T₃ Syndrome: A Randomized, Placebo-Controlled Study

Institute of Clinical Physiology (A.P., A.I., M.S., D.N., G.I.), Consiglio Nazionale delle Ricerche, 56124 Pisa, Italy; Cardiothoracic Department (E.G., A.B., R.M.), University of Pisa, 43-56126 Pisa, Italy; and Scuola Superiore Sant’Anna (A.L.), 34 56025 Pisa, Italy

Address all correspondence and requests for reprints to: Giorgio Iervasi, M.D., Clinical Physiology Institute, Consiglio Nazionale delle Ricerche, Via Moruzzi 1 Località la Fontina, 56124 Pisa, Italy. E-mail: iervasi{at}ifc.cnr.it.

Context: Low-T₃ syndrome is a predictor of poor outcome in patients with cardiac dysfunction. The study aimed to assess the short-term effects of synthetic L-T₃ replacement therapy in patients with low-T₃ syndrome and ischemic or nonischemic dilated cardiomyopathy (DC).

Design: A total of 20 clinically stable patients with ischemic (n = 12) or nonischemic (n = 8) DC were enrolled. There were 10 patients (average age 72 yr, range 66–77; median, 25–75th percentile) who underwent 3-d synthetic L-T₃ infusion (study group); the other 10 patients (average age 68 yr, range 64–71) underwent placebo infusion (control group). Clinical examination, electrocardiography, cardiac magnetic resonance, and bio-humoral profile (free thyroid hormones, TSH, plasma renin activity, aldosterone, noradrenaline, N-terminal-pro-B-Type natriuretic peptide, and IL-6) were assessed at baseline and after 3-d synthetic L-T₃ (initial dose: 20 µg/m² body surface·d) or placebo infusion.

Results: After T₃ administration, free T₃ concentrations increased until reaching a plateau at 24–48 h (3.43, 3.20–3.84 vs. 1.74, 1.62–1.93 pg/ml; P = 0.03) without side effects. Heart rate decreased significantly after T₃ infusion (63, 60–66 vs. 69, 60–76 beats per minute; P = 0.008). Plasma noradrenaline (347; 270–740 vs. 717, 413–808 pg/ml; P = 0.009), N-terminal pro-B-Type natriuretic peptide (3000, 438-4005 vs. 3940, 528-5628 pg/ml; P = 0.02), and aldosterone (175, 152–229 vs. 231, 154–324 pg/ml; P = 0.047) significantly decreased after T₃ administration. Neurohormonal profile did not change after placebo infusion in the control group. After synthetic L-T₃ administration, left-ventricular end-diastolic volume (142, 132–161 vs. 133, 114–158 ml/m² body surface; P = 0.02) and stroke volume (40, 34–44 vs. 35, 28–39 ml/m² body surface; P = 0.01) increased, whereas external and intracardiac workload did not change.

Conclusions: In DC patients, short-term synthetic L-T₃ replacement therapy significantly improved neuroendocrine profile and ventricular performance. These data encourage further controlled trials with more patients and longer periods of synthetic L-T₃ administration.

This article has been cited by other articles:

				I. Klein and S. Danzi Thyroid Hormone Treatment to Mend a Broken Heart J. Clin. Endocrinol. Metab., April 1, 2008; 93(4): 1172 - 1174. [Full Text] [PDF]