Thyroid hormones and heart failure

Effects of levothyroxine in subclinical hypothyroidism and heart failure with reduced ejection fraction: An open-label randomized trial

We report a randomized, multicenter, open-label trial (ClinicalTrials.gov: NCT03096613) to investigate the clinical benefits of levothyroxine (L-T4) administration in subclinical hypothyroidism (SCH) patients with heart failure with reduced ejection fraction (HFrEF). Overall, 117 patients were enrolled and received L-T4 plus standard HFrEF treatment (experimental group, N = 57) or standard HFrEF therapy alone (control group, N = 60). The change of 6-min walk test distance in the experimental group was significantly higher than that in the control group at 24 weeks (70.08 ± 85.76 m vs. 27.73 ± 82.00 m, mean difference [95% confidence interval (CI)] 46.90 [12.90, 80.90], p < 0.001). Improvements in New York Heart Association (NYHA) classification (p = 0.033) and thyroid function were significant. Adverse event incidence was similar between groups (risk ratio [95% CI]: 0.942 1.053 (0.424, 2.616); p = 0.628). L-T4 addition to HFrEF treatment improved activity tolerance, NYHA class, and thyroid function within 6 months, suggesting its potential for combined therapy in HFrEF patients with SCH. Future double-blind, placebo-controlled trials should be performed to confirm these results.

Rapid progression of heart failure secondary to radioactive iodine treatment of hyperthyroidism: A case report

BACKGROUND

The deterioration of thyroid health is involved in the progression of heart failure (HF). This is usually a lengthy process, so there are almost no reports on its rapid development. Here we report a case of a young male who rapidly developed hypothyroid cardiomyopathy secondary to radioactive iodine treatment, suggesting that severe HF might occur even after a short period of hypothyroidism.

CASE SUMMARY

A 26-year-old man was referred to our hospital for HF presenting with dyspnea on exertion and chest discomfort lasting for 1 mo. He received radioactive iodine treatment for hyperthyroidism 1 year ago and had an almost normal echocardiogram 6 mo ago. Admission echocardiogram and cardiac magnetic resonance (CMR) revealed left ventricle (LV) global hypokinesia and severely depressed systolic function. In addition, late gadolinium enhancement indicated no obvious changes in the myocardium. Thyroid function tests showed decreased serum levels of thyroid hormone (TH) and elevated thyroid-stimulating hormone. Based on an exclusionary examination, the patient was diagnosed with hypothyroid cardiomyopathy and was started on replacement therapy. His HF symptoms were completely relieved during the six-month follow-up, and echocardiogram and CMR revealed recovered LV size and ejection fraction.

CONCLUSION

This report demonstrates that severe fluctuations in TH levels may lead to acute HF, which can completely recover with timely thyroid hormone replacement. In addition, our findings highlight the importance of routinely detecting cardiac function in patients treated with radioactive iodine.

Rapid progression of heart failure secondary to radioactive iodine treatment of hyperthyroidism: A case report

BACKGROUND

The deterioration of thyroid health is involved in the progression of heart failure (HF). This is usually a lengthy process, so there are almost no reports on its rapid development. Here we report a case of a young male who rapidly developed hypothyroid cardiomyopathy secondary to radioactive iodine treatment, suggesting that severe HF might occur even after a short period of hypothyroidism.

CASE SUMMARY

A 26-year-old man was referred to our hospital for HF presenting with dyspnea on exertion and chest discomfort lasting for 1 mo. He received radioactive iodine treatment for hyperthyroidism 1 year ago and had an almost normal echocardiogram 6 mo ago. Admission echocardiogram and cardiac magnetic resonance (CMR) revealed left ventricle (LV) global hypokinesia and severely depressed systolic function. In addition, late gadolinium enhancement indicated no obvious changes in the myocardium. Thyroid function tests showed decreased serum levels of thyroid hormone (TH) and elevated thyroid-stimulating hormone. Based on an exclusionary examination, the patient was diagnosed with hypothyroid cardiomyopathy and was started on replacement therapy. His HF symptoms were completely relieved during the six-month follow-up, and echocardiogram and CMR revealed recovered LV size and ejection fraction.

CONCLUSION

This report demonstrates that severe fluctuations in TH levels may lead to acute HF, which can completely recover with timely thyroid hormone replacement. In addition, our findings highlight the importance of routinely detecting cardiac function in patients treated with radioactive iodine.

The effect and mechanism of excessive iodine on the endothelial function of human umbilical vein endothelial cells

Iodine excess (IE) can cause thyroid dysfunction, thyroid diseases can adversely affect cardiovascular function. Accordingly, this study was to explore the direct and indirect effects of IE on endothelial function. Nthy-ori 3-1 and HUVECs cells were treated with potassium iodide (KI). CCK-8, LDH leakage, Elisa, RT-PCR and Western blotting were used to detect relevant indicators. Results showed that a certain level of KI can directly and indirectly reduce the viability of HUVECs and increase cytotoxicity. KI decreased the expression of ET-1 and VWF in HUVECs, inhibited the secretion of ET-1 in culture medium, and increased the expression of IL-6 and TNFα in HUVECs or Nthy-ori 3-1 cells alone. In the co-culture system, KI decreased the expression of ET-1 and THBD and increased the expression of TNFα and IL-6. Collectively, IE can directly and indirectly inhibit endothelial function of endothelial cells, which may be related to its induced inflammatory response.

Cognitive decline in heart failure: Biomolecular mechanisms and benefits of exercise

By definition, heart failure (HF) is a human pathological condition affecting the structure and function of all organs in the body, and the brain is not an exception to that. Failure of the heart to pump enough blood centrally and peripherally is at the foundation of HF patients' inability to attend even the most ordinary daily activities and progressive deterioration of their cognitive capacity. What is more, between heart and brain exists a bidirectional relationship that goes well beyond hemodynamics and concerns bioelectric and endocrine signaling. This increasingly consolidated evidence makes the scenario even more complex. Studies have mainly chased how HF impairs cognition without focusing much on preventive measures, notably cardio-cerebral health proxies. Here, we aim to provide a brief account of known and hypothetical factors that may explain how exercise can help obviate cognitive dysfunction associated with HF in its different forms. As we shall see, there is a stringent need for a deeper grasp of such mechanisms. Indeed, gaining this new knowledge will automatically shed new light on the inner workings of HF itself, thus resulting in more effective prevention and treatment of this escalating syndrome.

The effectiveness of thyroid hormone replacement therapy on heart failure and low T3-syndrome: An updated systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The purpose of this study was to conduct a systematic review and meta-analysis evaluating the role of thyroid hormone therapy in patients with heart failure (HF) and low triiodothyronine (T3) syndrome (LT3S).

METHODS

The electronic databases PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database, Wanfang Database, and China Biology Medicine disc (CBMdisc) were systematically searched to identify eligible studies published before November 27, 2021. The mean difference was pooled for RCTs using a random-effects model.

RESULTS

The meta-analysis showed that thyroid hormone treatment improved the left ventricular ejection fraction (weighted mean difference [WMD] 5.61, 95% confidence interval [CI]: 4.38 to 6.85^, I² = 63.12%, P^<0.01). The cardiac output improved with thyroid hormone therapy (WMD 0.65, 95% CI: 0.42 to 0.89, I² = 84.28%, P^<0.01). The E/A in the thyroid hormone group was also improved compared to the control group (WMD 0.29, 95% CI: 0.15 to 0.42^, I² = 95.08%, P^<0.01). The left ventricular diastolic dysfunction was decreased with thyroid hormone treatment (WMD -5.17, 95% CI: -7.47 to -2.88, I² = 90.18%, P^<0.01). The brain natriuretic peptide decreased with thyroid hormone treatment (standardized mean difference [SMD] -1.49, 95% CI: -2.15 to -0.84, I² = 90.18%, P^<0.01). Noradrenaline decreased with thyroid hormone therapy (WMD -349.86, 95% CI: -401.05 to -298.67^, I² = 0%, P^<0.01). Free T3 increased with thyroid hormone treatment (SMD 2.18, 95% CI: 0.75 to 2.60^, I² = 98.20%, P^<0.01).

CONCLUSION

This meta-analysis showed that thyroid hormone replacement therapy was effective in patients with HF and LT3S.

Hypothyroidism Is Associated With Longer Hospital Stay Following Implantation Of Left Ventricular Assist Device

Background:

There has been a steady and consistent rise in the use of left ventricular assist devices in the management of patients with advanced heart failure. Hypothyroidism also remains one of the most common endocrine conditions with a significant impact on the development and overall outcomes of heart failure. The authors analyzed the National Inpatient Sample to evaluate the effect of hypothyroidism on the in-hospital outcomes of patients with end-stage heart failure following the placement of left ventricular assist device.

Methods:

The national inpatient sample was queried to identify all adult patients who had LVAD placement from 2004 to 2014. They were subsequently divided into those with hypothyroidism and those without hypothyroidism. The primary outcome was in-hospital mortality. Other outcomes were acute kidney injury, length, and cost of hospitalization. Logistic regression models were created to determine the outcomes of interest.

Results:

Of 2643 patients in the study, 5.4% had hypothyroidism, and 94.6% did not. The hypothyroid patients were significantly older compared to the non-hypothyroid patients (mean age 58.6 years vs 49.95 years, P-value <.0001). Both groups had similar gender composition. In-hospital mortality was similar across both groups. However, there was a higher incidence of acute kidney injury (AKI) in the hypothyroid group (adjusted odds ratio [aOR 1.83, P-value <.001]). Hypothyroid patients had longer hospital stays (adjusted mean difference [aMD] 5.19, P-value .0001). Hospital charges were also higher in the hypothyroid group.

Conclusion:

This study found that LVAD is associated with longer hospital stay in hypothyroid patients with heart failure.

Cardiac retinoic acid levels decline in heart failure

Although low circulating levels of the vitamin A metabolite, all-trans retinoic acid (ATRA), are associated with increased risk of cardiovascular events and all-cause mortality, few studies have addressed whether cardiac retinoid levels are altered in the failing heart. Here, we showed that proteomic analyses of human and guinea pig heart failure (HF) were consistent with a decline in resident cardiac ATRA. Quantitation of the retinoids in ventricular myocardium by mass spectrometry revealed 32% and 39% ATRA decreases in guinea pig HF and in patients with idiopathic dilated cardiomyopathy (IDCM), respectively, despite ample reserves of cardiac vitamin A. ATRA (2 mg/kg/d) was sufficient to mitigate cardiac remodeling and prevent functional decline in guinea pig HF. Although cardiac ATRA declined in guinea pig HF and human IDCM, levels of certain retinoid metabolic enzymes diverged. Specifically, high expression of the ATRA-catabolizing enzyme, CYP26A1, in human IDCM could dampen prospects for an ATRA-based therapy. Pertinently, a pan-CYP26 inhibitor, talarozole, blunted the impact of phenylephrine on ATRA decline and hypertrophy in neonatal rat ventricular myocytes. Taken together, we submit that low cardiac ATRA attenuates the expression of critical ATRA-dependent gene programs in HF and that strategies to normalize ATRA metabolism, like CYP26 inhibition, may have therapeutic potential.

Hypothyroidism impairs the host immune response during the acute phase of Chagas disease

Diseases associated with thyroid hypofunction have been the subject of studies in infectious models, since several authors have demonstrated a pivotal role of iodinated hormones (thyroxine and triiodothyronine) in the modulation of immune effector responses. Using a model of hypothyroidism induced by anti-thyroid drug, we investigated the influence of hypothyroidism in the course of acute Trypanosoma cruzi infection. For this, male Hannover Wistar rats were challenged with methimazole for 21 days (0.02% in drinking water), and water for control counterparts. After confirmation of the hypothyroidism, rats were intraperitoneally challenged with 1x10⁵ blood trypomastigotes of the Y strain of T. cruzi. Our findings suggest that hypothyroidism impairs animal weight gain, but does not affect the health of essential organs. Interestingly, infected hypothyroid animals had a significant increase in thymic cell death, with consequent drop in lymphocyte frequency in whole blood (evaluated on the 11th day of infection). Analyzing the percentage of immune cells in the spleen, we found a strong influence of hypothyroidism as a negative regulator of B cells, and antigenic ability of macrophages (RT1b expression) in the course of the experimental chagasic infection. Enhanced serum IL-17A concentration was induced by T. cruzi infection, but hypothyroidism impaired the production of this mediator as seen in infected hypothyroid animals. Taken together, our work suggests for the first time that hypothyroidism may adversely interfere with the modulation of effective immunity in the early phase of Chagas' disease.

Comorbidities in chronic heart failure: An update from Italian Society of Cardiology (SIC) Working Group on Heart Failure

The increasing number of patients with heart failure HF and comorbidities is due to aging population and increase of life expectancy of patients with cardiovascular disease. Encouraging results derived by recent trials may suggest some comorbidities as new targets for new drugs, highlighting the need for a better understanding of the comorbidities' effects in HF patients and the need of a multidisciplinary approach for the management of chronic HF with comorbidities. We report a brief review about main cardiovascular and non-cardiovascular comorbidities in HF patients in order to update physicians and researchers engaged in the HF research or in "fight against heart failure."

Thyroid Function in Patients With a Fontan Circulation

In this study, we tested our hypothesis that thyroid function is impaired and contributes to perturbed hemodynamics in patients after Fontan operation. Cardiac catheterization and blood tests for thyroid function were performed in 37 patients who underwent a Fontan operation. Among them, 12 patients (33%) had subclinical thyroid dysfunction with an elevated thyroid-stimulating hormone level despite normal thyroxine levels. Thyroid-stimulating hormone levels were significantly correlated with central venous pressure (p <0.01, R² = 0.3), and patients with subclinical hypothyroidism showed significantly elevated γ-glutamyltransferase level, an indicator of liver congestion, compared with the other patients (125.6 ± 12.2 vs 67.6 ± 4.6 IU/L, p <0.01). In addition, the levels of free triiodothyronine, an effective thyroid hormone, were significantly lower in patients with subclinical hypothyroidism than in those with normal thyroid function (3.1 ± 0.1 vs 3.5 ± 0.1 pg/dl, p <0.01). The free triiodothyronine level was significantly and negatively correlated with the relaxation time constant (p = 0.03) and brain natriuretic hormone (p <0.01) level and positively correlated with the cardiac index (p = 0.04). In conclusion, venous congestion in Fontan patients may cause thyroid dysfunction, which can be responsible for decreased ventricular function and cardiac output in Fontan patients. Thus, thyroid function should be routinely monitored after Fontan surgery.

Performance-Enhancing Drugs Abuse Caused Cardiomyopathy and Acute Hepatic Injury in a Young Bodybuilder

A number of performance-enhancing drugs (PEDs) are used illicitly to improve muscle strength by the bodybuilders. The misuse of these drugs is associated with serious adverse effects to different organs. A previously healthy 22-year-old male bodybuilder after taking stanozolol, clenbuterol, and triiodothyronine for 10 days presented to the hospital with symptoms of icteric sclera, progressive dyspnea, intermittent cough, and bloody sputum. He was diagnosed with dilated cardiomyopathy and acute hepatic injury. Rapidly progressive dilated cardiomyopathy and acute hepatic injury among bodybuilders in such a short period of time have not been reported. People using these drugs must monitor liver and cardiac functions regularly, and they should discontinue using PEDs after diagnosis of liver or cardiac abnormalities. Physicians should always consider the possibility of the PED abuse in the context of a young athlete suffering cardiomyopathy or hepatic injury.

A multicenter phase II study of sunitinib in patients with locally advanced or metastatic differentiated, anaplastic or medullary thyroid carcinomas: mature data from the THYSU study

PURPOSE

Patients with advanced radioactive iodine resistant differentiated (MDTC) or medullary (MMTC) thyroid cancer had an unmet need. Early data showed promising efficacy of vascular endothelial growth factor receptor inhibitors. We investigated sunitinib in this setting.

PATIENTS AND METHODS

This phase 2 trial enrolled MDTC, anaplastic (MATC) and MMTC patients in 1st line anti-angiogenic therapy with sunitinib at 50 mg/d, 4/6w. Objective response rate was the primary end-point. Secondary end-points were progression-free survival, overall survival and safety.

RESULTS

Seventy-one patients were enrolled from August 2007 to October 2009, 41 MDTC/4 MATC patients and 26 MMTC patients. Patients received a median of 8 and 9 cycles, respectively. In the MDTC/MATC group, 13% of patients and 43% of cycles and in the MMTC group, 23% of the patients and 48.8% of cycles remained at 50 mg/d, respectively. The primary end-point was reached with an objective response rate of 22% (95% CI: 10.6-37.6) in MDTC patients and in 38.5% (95% CI: 22.6-56.4) in MMTC patients. No objective response was seen in MATC patients. Median progression-free survival and overall survival were 13.1 and 26.4 months in MDTC patients, 16.5 and 29.4 months in MMTC patients. The most frequent side effects were asthenia/fatigue (27.8% ≥ grade 3), mucosal (9.9% ≥ grade 3), cutaneous toxicities, hand-foot syndrome (18.3% ≥ grade 3). Of all, 14.1% had a cardiac event. Nine unexpected side effects were reported, out of which, five induced deaths.

CONCLUSION

Sunitinib is active in MDTC and MMTC patients. Side effects were more severe than with previous reports. If using sunitinib, alternative schedule/dosage should be considered.