Background: Both the morbidity and mortality rates from congestive heart failure (CHF)
remain elevated despite the medical and non-medical management of the disease, thus suggesting the
existence of residual risk factors such as thyroid dysfunction. Particularly, the 15-30% of patients with
CHF, especially those with severe ventricular dysfunction, display the so-called low T3 syndrome
(LT3S), which seems to negatively affect the cardiovascular prognosis.
Objective: Only a few clinical trials have been carried out to verify both the safety and the efficacy of
thyroid replacement in the LT3S, aiming to ameliorate the prognosis of CHF, and most of the results
Methods: Since the aim of the present review was to briefly overview both the indication and contraindication
of triiodothyronine replacement in CHF and LT3S, the authors searched PubMed using the
medical subject headings (MeSH) related to the following terms: “congestive heart failure” and “low
T3 syndrome” or “euthyroid sick syndrome” or “non-thyroidal sick syndrome”. The research study
only focused on the narrative and systematic reviews, randomized clinical trials and meta-analysis
studies which were conducted before June 2019.
Results: Studies conducted in both animal models and humans provided controversial information
about the effectiveness and safety of the T3 replacement for improving ventricular dysfunction, particularly
in the long-term.
Conclusion: Further clinical trials are needed to better explore the role of LT3S in patients with CHF
and its consequent therapeutic strategy in this clinical setting.