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Novel insights in endocrine and metabolic pathways in sepsis and gaps for future research. Clin Sci (Lond) 2022; 136:861-878. [PMID: 35642779 DOI: 10.1042/cs20211003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 11/17/2022]
Abstract
Sepsis is defined as any life-threatening organ dysfunction caused by a dysregulated host response to infection. It remains an important cause of critical illness and has considerable short- and long-term morbidity and mortality. In the last decades, preclinical and clinical research has revealed a biphasic pattern in the (neuro-)endocrine responses to sepsis as to other forms of critical illness, contributing to development of severe metabolic alterations. Immediately after the critical illness-inducing insult, fasting- and stress-induced neuroendocrine and cellular responses evoke a catabolic state in order to provide energy substrates for vital tissues, and to concomitantly activate cellular repair pathways while energy-consuming anabolism is postponed. Large randomized controlled trials have shown that providing early full feeding in this acute phase induced harm and reversed some of the neuro-endocrine alterations, which suggested that the acute fasting- and stress-induced responses to critical illness are likely interlinked and benefical. However, it remains unclear whether, in the context of accepting virtual fasting in the acute phase of illness, metabolic alterations such as hyperglycemia are harmful or beneficial. When patients enter a prolonged phase of critical illness, a central suppression of most neuroendocrine axes follows. Prolonged fasting and central neuroendocrine suppression may no longer be beneficial. Although pilot studies have suggested benefit of fasting-mimicking diets and interventions that reactivate the central neuroendocrine suppression selectively in the prolonged phase of illness, further study is needed to investigate patient-oriented outcomes in larger randomized trials.
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Endocrine and Electrolyte Disorders. Perioper Med (Lond) 2022. [DOI: 10.1016/b978-0-323-56724-4.00040-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Wang J, Cao J, Zhu J, Liu N. Non-Thyroidal Illness Syndrome-Associated Multiorgan Dysfunction After Surgical Repair of Type A Aortic Dissection. J Cardiothorac Vasc Anesth 2021; 36:870-879. [PMID: 34507886 DOI: 10.1053/j.jvca.2021.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 07/23/2021] [Accepted: 08/02/2021] [Indexed: 11/11/2022]
Abstract
OBJECTIVE The purpose of this cohort study was to investigate the relationship between non-thyroidal illness syndrome (NTIS) and severe multiorgan dysfunction, measured by Sequential Organ Failure Assessment score ≥11, after surgical repair of type A aortic dissection (TAAD). SETTING An observational study. PARTICIPANTS The present study included 310 patients with TAAD surgically repaired between January 2019 and December 2020 in Beijing Anzhen Hospital. INTERVENTIONS Patients after surgical repair after TAAD. MEASUREMENTS AND MAIN RESULTS Among a total of 310 patients with TAAD undergoing surgical repair included in this study, 132 (42.6%) experienced surgery-associated NTIS. Severe multiorgan dysfunction was experienced more often in patients with NTIS (27.3% v 11.2%, p < 0.0001). Multivariate analysis demonstrated NTIS was associated closely with an increased risk of severe multiorgan dysfunction (odds ratio [OR] = 2.54, 95% CI = 1.39-4.64 p = 0.002), which predicted an in-hospital death rate of 95%. Non-thyroidal illness syndrome also was related with in-hospital major adverse cardiovascular and cerebral events (OR = 2.12, 95% CI = 1.30-3.46 p = 0.003), acute kidney injury (OR = 3.17, 95% CI = 1.17-8.47 p = 0.023), and postoperative pulmonary complications (OR = 2.32, 95% CI = 1.34-4.03 p = 0.003). However, hepatic inadequacy was comparable in the NTIS and control groups. CONCLUSIONS Non-thyroidal illness syndrome was associated closely with multiorgan dysfunction after surgical repair of TAAD, which may be correlated further with an increased incidence of in-hospital mortality and complications.
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Affiliation(s)
- Jiayang Wang
- Department of Cardiac Surgery, Beijing An Zhen Hospital Capital Medical University, Beijing, China; Center for Cardiac Intensive Care, Beijing An Zhen Hospital Capital Medical University, Beijing, China; Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Disease, Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease, Clinical Center for Coronary Heart Disease, Capital Medical University, Beijing, China
| | - Jian Cao
- Department of Cardiac Surgery, Beijing An Zhen Hospital Capital Medical University, Beijing, China
| | - Junming Zhu
- Department of Cardiac Surgery, Beijing An Zhen Hospital Capital Medical University, Beijing, China
| | - Nan Liu
- Center for Cardiac Intensive Care, Beijing An Zhen Hospital Capital Medical University, Beijing, China.
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Bibi S, Shah M, Malik MO, Goosens KA. T3 is linked to stress-associated reduction of prolactin in lactating women. J Neuroendocrinol 2021; 33:e13003. [PMID: 34241933 DOI: 10.1111/jne.13003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/01/2021] [Accepted: 06/13/2021] [Indexed: 11/26/2022]
Abstract
The relationship between stress responses and lactation is bidirectional. Breastfeeding confers many benefits to maternal health, including attenuated hypothalamic-pituitary-adrenal axis responsiveness to stress. However, increased stress burden can impair lactation. The mechanisms that underlie these relationships are poorly understood. The present study aimed to compare breastfeeding habits, as well as subjective and objective measures of stress, in employed and non-employed lactating women and assess the relationships between these measures and prolactin (PRL), thyroid hormones (thyroid-stimulating hormone, triiodothyronine [T3] and thyroxine), vasopressin and cortisol levels. A dexamethasone suppression test was also administered to determine the sensitivity of the hypothalamic-pituitary-adrenal axis to negative-feedback. We report that lactating employed women had lower breastfeeding rates and lower PRL than lactating non-employed women. They also had a significantly higher stress burden, indicated by elevations in blood pressure and evening cortisol, relative to lactating non-employed women. In regression analyses that controlled for feeding modality and breastfeeding duration, we found these factors differentially affected PRL in the two groups and there were significant differences in PRL across groups that were not accounted for by these factors. A mediation regression analysis suggested that group differences in PRL were best explained by differences in T3 and income levels, rather than breastfeeding duration or other variables. Our data fit a speculative model in which elevated maternal stress increases cortisol, which suppresses T3, leading to decreased PRL. The decreases in PRL are associated with higher rates of bottlefeeding, which may further contribute to decreased PRL.
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Affiliation(s)
- Safia Bibi
- Department of Physiology, Institute of Basic Medical Sciences, Khyber Medical University, Peshawar, Pakistan
| | - Mohsin Shah
- Department of Physiology, Institute of Basic Medical Sciences, Khyber Medical University, Peshawar, Pakistan
| | - Muhammad Omar Malik
- Department of Physiology, Institute of Basic Medical Sciences, Khyber Medical University, Peshawar, Pakistan
| | - Ki Ann Goosens
- Department of Psychiatry and Center for Affective Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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Nistal-Nuño B. Euthyroid sick syndrome in paediatric and adult patients requiring extracorporeal circulatory support and the role of thyroid hormone supplementation: a review. Perfusion 2020; 36:21-33. [PMID: 32423366 DOI: 10.1177/0267659120914136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Non-thyroid disorders may modify thyroid hormone metabolism, resulting in an 'euthyroid sick syndrome'. Studies determining the association of cardiopulmonary bypass to thyroid function showed changes in line with this euthyroid sick syndrome. In some cases, cardiovascular dysfunction after cardiac surgery with cardiopulmonary bypass is comparable to that noticed in hypothyroidism associated with low cardiac output and elevated systemic vascular resistance. Numerous lines of research have proposed that triiodothyronine can behave acutely as a positive inotropic and vasodilator agent. The aim of this review is to present an update on the current literature about in what clinical situations the use of thyroid supplementation during the perioperative period of extracorporeal circulation in the adult and paediatric populations may impact outcome to any appreciable degree. The contribution of thyroid function in patients undergoing a ventricular assist device implantation is additionally reviewed and future study directions are proposed. This is a narrative review, where the search strategy consisted on retrieving the articles through an extensive literature search performed using electronic databases from January 1978 up to September 2019. All controlled trials randomly allocating to perioperative thyroid hormone administration in children and adults undergoing extracorporeal circulation for cardiac surgery were considered. Thyroid hormone supplementation may be recommended particularly in selected paediatric sub-populations. There is currently no firm evidence regarding the benefits of routine use of thyroid hormone administration in cardiac adult patients. Further studies are required to assess the beneficial effect of thyroid hormone on patients with end-stage heart failure supported by ventricular assist devices.
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Affiliation(s)
- Beatriz Nistal-Nuño
- Department of Anesthesiology, Complejo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain
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D Souza TF, Hoshal SG, Albeiruti R, Zambito MP, Zambito GM, Khan FM, Samuel BP, Crumb TL, Rajasekaran S, Vettukattil JJ. Transient Secondary Hypothyroidism and Thyroid Hormone Replacement Therapy in Pediatric Postoperative Cardiopulmonary Bypass. Curr Cardiol Rev 2018; 14:121-127. [PMID: 29485000 PMCID: PMC6088443 DOI: 10.2174/1573403x14666180226160749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 01/22/2018] [Accepted: 02/20/2018] [Indexed: 12/02/2022] Open
Abstract
Background: To develop an understanding of current practices in the management of transient secondary hypothyroidism in pediatric postoperative cardiopulmonary bypass (CPB) patients. Methods: Electronic survey comprising a 10-item questionnaire was sent to sixty-four high volume pediatric heart centers in the United States and United Kingdom. Survey participants included cardiologists, intensivists, cardiothoracic surgeons, and advanced practice providers. A retrospective chart review was also performed at a large regional referral center in the Midwest on subjects 0-18 years old who underwent CPB from 2005-2015. Information obtained included a unique identifier, date of birth, age, procedure performed, CPB time, date of surgery and date and type of Thyroid Function Test (TFT) ordered. Results: 1,153 individuals from 64 congenital heart centers were contacted via email to participate in the electronic survey. In the 3-month response window, 129 completed surveys were received from cardiologists (55%), intensivists (17%), surgeons (15%), “other” (8%), and advanced practice providers (5%). This yielded a response rate of 11.2%. Of the 129 respondents, only 10 providers routinely order TFTs prior to (n=7) and after (n=1) CPB or when clinically indicated (n=2). All 10 providers order thyroid stimulating hormone test, 7 order thyroxine, and 3 order triiodothyronine. Only 1 provider routinely treats children with prophylactic thyroid hormone replacement therapy after CPB. Our retrospective review included 502 CPB events with 442 unique patients. Of the events, 20 patients received preoperative TFT testing while 11 received postoperative testing. Conclusions: There is a general lack of uniformity in the evaluation, diagnosis, and treatment of transient secondary hypothyroidism in pediatric postoperative CPB patients.
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Affiliation(s)
- Travis F D Souza
- College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Steven G Hoshal
- College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Ridwaan Albeiruti
- College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Mario P Zambito
- College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Giuseppe M Zambito
- College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Faizan M Khan
- College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Bennett P Samuel
- Congenital Heart Center, Helen DeVos Children`s Hospital, Grand Rapids, MI, United States
| | - Teri L Crumb
- Office of Clinical Research Operations, Offices of Research Administration, Spectrum Health System, Grand Rapids, MI, United States
| | - Surender Rajasekaran
- Pediatric Critical Care Medicine, Helen DeVos Children's Hospital, Grand Rapids, MI, United States
| | - Joseph J Vettukattil
- Congenital Heart Center, Helen DeVos Children`s Hospital, Grand Rapids, MI, United States
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Paolino BS, Pomerantzeff PM, Dallan LAO, Gaiotto FA, Preite NZ, Latrônico AC, Nicolau JC, Bianco AC, Giraldez RRCV. Myocardial Inactivation of Thyroid Hormones in Patients with Aortic Stenosis. Thyroid 2017; 27:738-745. [PMID: 28095748 PMCID: PMC5749598 DOI: 10.1089/thy.2016.0514] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE The human heart expresses the type 2 deiodinase (D2) that activates thyroxine (T4) to triiodothyronine (T3). At the same time, the inactivating type 3 deiodinase (D3) has been found in a rat model of right ventricular hypertrophy. It is not known whether the human myocardium metabolizes thyroid hormone. This study examined myocardial thyroid hormone metabolism in patients with aortic valve stenosis (AS) undergoing aortic valve replacement and in patients with coronary artery disease (CAD) undergoing coronary artery bypass grafting surgery. METHODS Myocardial thyroid hormone metabolism was assessed by analyzing the difference in serum thyroid hormone levels between the aortic root (incoming blood) and the coronary sinus (outgoing blood) of patients undergoing cardiac surgery. A total of 23 patients with AS and 35 patients with CAD were included. Patients received a pre-surgical echocardiogram, and pre-, during and post-surgical thyroid hormone serum levels were collected in the myocardial and peripheral circulations. RESULTS Patients with AS exhibited the expected left ventricle (LV) hypertrophy (i.e., 20-30% increase in LV posterior wall and interventricular septum thickness and ∼10% increase in AS in LV diastolic diameter). Immediately before cardiopulmonary bypass, blood flowing through the AS myocardium exhibited a 4.6% reduction in T3 and 6.9% increase in rT3 levels, decreasing the serum T3/rT3 ratio by 9.6%. T4 and thyrotropin serum levels remained similar between the aortic root and coronary sinus. In contrast, no myocardial thyroid hormone metabolism was observed in CAD patients. Notably, the AS myocardium lost the ability to inactivate thyroid hormone after cardiopulmonary bypass, possibly due to myocardial stunning. CONCLUSIONS There is accelerated thyroid hormone inactivation in the AS myocardium, which is likely the result of D3 expression. No evidence to suggest thyroid hormone activation in the myocardium was obtained in the present study.
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Affiliation(s)
- Bruno S. Paolino
- Heart Institute of the University of São Paulo Medical School, Sao Paulo, Brazil
| | | | | | - Fabio A. Gaiotto
- Heart Institute of the University of São Paulo Medical School, Sao Paulo, Brazil
| | - Nailliw Z. Preite
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Rush University Medical Center, Chicago, Illinois
| | | | - José Carlos Nicolau
- Heart Institute of the University of São Paulo Medical School, Sao Paulo, Brazil
| | - Antonio C. Bianco
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Rush University Medical Center, Chicago, Illinois
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Hypothyroidism complicates bradyarrhythmic episodes in a heart-transplanted patient: Can it be treated with low-dose dopamine? POLISH JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY 2015; 12:377-8. [PMID: 26855660 PMCID: PMC4735545 DOI: 10.5114/kitp.2015.56794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 04/14/2014] [Indexed: 11/17/2022]
Abstract
Extracorporeal circulation decreases thyroid hormone levels in peripheral blood. This clinical entity may complicate the postoperative period after heart transplantation if the recipient has taken thyroid hormone replacement therapy. Cardiac transplantation was performed on a patient in whom thyroid hormone levels decreased after surgery. Sinus bradycardia was seen after surgery (30-40 bpm). Thyroid hormones were replaced in the patient. Due to the fact that temporary pacing decreased blood pressure, dopamine was safely given in very low doses. This case was discussed under the literature knowledge.
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Worku B, Tortolani AJ, Gulkarov I, Isom OW, Klein I. Preoperative hypothyroidism is a risk factor for postoperative atrial fibrillation in cardiac surgical patients. J Card Surg 2015; 30:307-12. [PMID: 25640607 DOI: 10.1111/jocs.12513] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND AIM Although studies analyzing the effect of thyroid supplementation on postoperative morbidity and mortality from cardiac surgery have been inconclusive, they suggest a role in the prevention of postoperative atrial fibrillation. To further explore this relationship we conducted a retrospective study to determine whether abnormalities in routine preoperative thyroid function studies correlate with the incidence of postoperative atrial fibrillation. METHODS From May 2004 until July 2011, 821 patients with complete thyroid function testing performed preoperatively underwent cardiac surgery. Preoperative, intraoperative, and postoperative laboratory, clinical and hemodynamic data including postoperative electrocardiogram monitoring were retrospectively evaluated. RESULTS Mean age was 65.7 years and 36% (294) of patients were female. Mean preoperative ejection fraction was 48.6% and 18% (100) had clinical heart failure. Ninety percent (682) of patients were euthyroid and 10% (77) were hypothyroid. Atrial fibrillation occurred significantly more frequently in hypothyroid patients (33.4% vs. 22.5%; p = .033). In multivariable analysis, increasing thyroid stimulating hormone (TSH) level (OR: 1.11; CI: 1.01 to 1.22; p = .030) was an independent predictor of postoperative atrial fibrillation. Beta blocker use within 24 hours prior to operation was protective (OR: .54; CI: .35 to .83; p = .005). Length of stay was significantly longer in patients with postoperative atrial fibrillation (9.1 vs. 6.5 days; p < .001). CONCLUSIONS In the current study, preoperative hypothyroidism was associated with postoperative atrial fibrillation. Further studies are warranted to delineate whether preoperative hypothyroidism is a useful biomarker for selecting patients most likely to benefit from preoperative thyroid supplementation in the prevention of postoperative atrial fibrillation.
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Affiliation(s)
- Berhane Worku
- Department of Cardiothoracic Surgery, New York Methodist Hospital, Brooklyn, New York; Department of Cardiothoracic Surgery, New York Presbyterian Hospital/Weil Cornell Medical Center, New York City, New York
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Abstract
Hypothyroidism in patients undergoing congenital heart defect surgery is known to be possible. This generally temporary condition can progress as it involves yet other factors, increasing the patients' time to heal. The case presented here is that of a 5-month-old girl who was dependent in the long term on mechanical ventilation following cardiac surgery. After having been diagnosed with hypothyroidism, she was extubated on the fourth day of her hormone replacement therapy, and discharged from hospital on the tenth day.
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11
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Conte JV. Invited commentary. Ann Thorac Surg 2014; 97:2095-6. [PMID: 24882289 DOI: 10.1016/j.athoracsur.2014.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 03/27/2014] [Accepted: 04/01/2014] [Indexed: 10/25/2022]
Affiliation(s)
- John V Conte
- Division of Cardiac Surgery, Johns Hopkins Medical Institutions, Division of Cardiac Surgery, 1800 Orleans St, Zayed 7107, Baltimore, MD21287.
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12
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Cerillo AG, Storti S, Kallushi E, Haxhiademi D, Miceli A, Murzi M, Berti S, Glauber M, Clerico A, Iervasi G. The low triiodothyronine syndrome: a strong predictor of low cardiac output and death in patients undergoing coronary artery bypass grafting. Ann Thorac Surg 2014; 97:2089-95. [PMID: 24636708 DOI: 10.1016/j.athoracsur.2014.01.049] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/04/2014] [Accepted: 01/14/2014] [Indexed: 11/17/2022]
Abstract
BACKGROUND There is strong clinical and experimental evidence that altered thyroid homeostasis negatively affects survival in cardiac patients, but a negative effect of the low triiodothyronine (T3) syndrome on the outcome of coronary artery bypass grafting (CABG) has not been demonstrated. This study was designed to evaluate the prognostic significance of low T3 syndrome in patients undergoing CABG. METHODS The thyroid profile was evaluated at hospital admission in 806 consecutive CABG patients. Known thyroid disease, severe systemic illness, and use of drugs interfering with thyroid metabolism were considered exclusion criteria. The effect of the baseline free T3 (fT3) concentration and of preoperative low T3 syndrome (fT3 <2.23 pmol/L) on the risk of low cardiac output (CO) and death was analyzed in a logistic regression model. RESULTS There were 19 (2.3%) deaths, and 64 (7.8%) patients experienced major complications. After univariate analysis, fT3, low T3, New York Heart Association class greater than II, low left ventricular ejection fraction (LVEF), and emergency were associated with low CO and hospital death. History of atrial fibrillation, cardiopulmonary bypass time, and peripheral vascular disease were associated only with low CO. At multivariate analysis, only fT3, low T3, emergency, and LVEF were associated with low CO, and fT3 (odds ratio, 0.172, 95% confidence interval, 0.078 to 0.379; p < 0.0001) and LVEF (odds ratio, 0.934, 95% confidence interval, 0.894 to 0.987; p = 0.03) were the only independent predictors of death. CONCLUSIONS Our study demonstrates that low T3 is a strong predictor of death and low CO in CABG patients. For this reason, the thyroid profile should be evaluated before CABG, and patients with low T3 should be considered at higher risk and treated accordingly.
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Affiliation(s)
- Alfredo Giuseppe Cerillo
- Operative Unit of Cardiac Surgery, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy.
| | - Simona Storti
- Clinical Chemistry Laboratory, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Enkel Kallushi
- Operative Unit of Cardiac Surgery, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Dorela Haxhiademi
- Anesthesia and Intensive Care, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Antonio Miceli
- Operative Unit of Cardiac Surgery, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Michele Murzi
- Operative Unit of Cardiac Surgery, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Sergio Berti
- Cardiology, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Mattia Glauber
- Operative Unit of Cardiac Surgery, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Aldo Clerico
- Clinical Chemistry Laboratory, "G. Pasquinucci" Hospital, "G. Monasterio" Foundation, Massa, Italy
| | - Giorgio Iervasi
- Operative Unit of Cardiovascular Endocrinology and Metabolism, "G. Monasterio" Foundation, Istituto di Fisiologia Clinica del Consiglio Nazionale delle Ricerche, Pisa, Italy
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Tian W, Tong H, Sun Y, Li X, Wu Q, Ma C, Jiao P. [Comparison of the changes of thyroid hormones after video-assisted thoracoscopic surgery and conventional thoracotomy in patients with non-small cell lung cancer]. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2013; 16:651-5. [PMID: 24345490 PMCID: PMC6000639 DOI: 10.3779/j.issn.1009-3419.2013.12.06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND AND OBJECTIVE Video-assisted thoracoscopic surgery (VATS) is the representative thoracic minimally invasive surgery. Compared with traditional open surgery (TOS), VATS has an advantage of less invasiveness, quicker recovery and milder postoperative pain. The aim of this study is to compare the influences of VATS and conventional thoracotomic lobectomy on thyroid hormones in treatment for non-small cell lung cancer (NSCLC). METHODS From Oct. 2010 to Aug. 2012, 44 consecutive patients with NSCLC were recruited and divided into two groups: VATS group (25 patients) and TOS group (19 patients). All the patients were drawn blood to measure the plasma levels of free T3, free T4, reverse T3 and TSH on the morning of the day before surgery, the postoperative day (POD)1, POD2, POD3 and POD7. We described the perioperative variation trend of the thyroid hormones and compared the differences between VATS group and TOS group. RESULTS There were no differences of thyroid hormone levels between the two groups before surgery. After surgery, the levels of FT3 and TSH were first dropped, then elevated and reached the lowest level on POD3 and POD1 separately. On POD7, they regained the before-surgery levels in VATS group while FT3 level was still significantly lower in TOS group (P=0.032). The FT4 and rT3 levels were first elevated, and then dropped after surgery. They both reached the peak concentrations on POD2, and rT3 levels of TOS group were significantly higher than those of VATS group on POD1, POD2 and POD3 (P<0.05). The changes of FT3 and rT3 levels were beyond normal ranges while changes of FT4 and TSH levels were within normal ranges. When variation trend of all the thyroid hormones were compared between the two groups, only rT3 level was found to have significant statistical differences (F=7.557, P=0.009). CONCLUSIONS All NSCLC patients after lobectomy have Euthyroid sick syndrome (ESS). Compared with traditional thoracotomy, VATS surgery has smaller influence on perioperative thyroid hormones and demonstrates a weaker acute stress reaction, which can benefit postoperative recovery of NSCLC patients.
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Affiliation(s)
- Wenxin Tian
- Department of Thoracic Surgery, Beijing Hospital, Beijing 100730, China
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Chen CY, Tsai MM, Chi HC, Lin KH. Biological significance of a thyroid hormone-regulated secretome. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:2271-84. [PMID: 23429180 DOI: 10.1016/j.bbapap.2013.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Revised: 02/07/2013] [Accepted: 02/11/2013] [Indexed: 01/18/2023]
Abstract
The thyroid hormone, 3,3,5-triiodo-L-thyronine (T3), modulates several physiological processes, including cellular growth, differentiation, metabolism and proliferation, via interactions with thyroid hormone response elements (TREs) in the regulatory regions of target genes. Several intracellular and extracellular protein candidates are regulated by T3. Moreover, T3-regulated secreted proteins participate in physiological processes or cellular transformation. T3 has been employed as a marker in several disorders, such as cardiovascular disorder in chronic kidney disease, as well as diseases of the liver, immune system, endocrine hormone metabolism and coronary artery. Our group subsequently showed that T3 regulates several tumor-related secretory proteins, leading to cancer progression via alterations in extracellular matrix proteases and tumor-associated signaling pathways in hepatocellular carcinomas. Therefore, elucidation of T3/thyroid hormone receptor-regulated secretory proteins and their underlying mechanisms in cancers should facilitate the identification of novel therapeutic targets. This review provides a detailed summary on the known secretory proteins regulated by T3 and their physiological significance. This article is part of a Special Issue entitled: An Updated Secretome.
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Affiliation(s)
- Cheng-Yi Chen
- Department of Biochemistry, College of Medicine, Chang-Gung University, Taoyuan 333, Taiwan
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Talwar S, Khadgawat R, Sandeep JA, Sreenivas V, Choudhary SK, Gupta N, Airan B. Cardiopulmonary bypass and serum thyroid hormone profile in pediatric patients with congenital heart disease. CONGENIT HEART DIS 2012; 7:433-40. [PMID: 22613232 DOI: 10.1111/j.1747-0803.2012.00667.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To study the effect of cardiopulmonary bypass (CPB) on serum thyroid hormone profile in children undergoing open-heart surgery. DESIGN Prospective cross-sectional study. SETTING Multispecialty tertiary level referral center. PATIENTS One hundred consecutive patients (age 15.9 ± 14.6 months, weight 6.7 ± 2.5 kg) undergoing open-heart surgery under CPB. INTERVENTIONS None. OUTCOME MEASURES Levels and trends of serum total thyroxine (TT4), free thyroxine (FT4), total tri-iodothyronine (TT3), free tri-iodothyronine (FT3) and thyroid stimulating hormone (TSH), survival, inotropic score, duration of mechanical ventilation, postoperative complications. RESULTS TT4 levels were 9.08 ± 3.6, 6.4 ± 2.5, 6.24 ± 2.1, 6.43 ± 2.4, 7.20 ± 3.0 µg/dL at baseline and at 1, 24, 48 and 72 hours; FT4 levels were 1.82 ± 0.5, 1.49 ± 0.3, 1.29 ± 0.3, 1.32 ± 0.4, and 1.43 ± 0.5 ng/dL; TT3 levels were 1.81 ± 0.4, 1.31 ± 0.3, 0.99 ± 0.2, 1.0 ± 0.37, and 1.17 ± 0.48 ng/ml; FT3 levels were 4.09 ± 1.0, 3.02 ± 0.8, 2.21 ± 0.6, 2.22 ± 0.7, and 2.66 ± 1.05 pg/ml; TSH levels were 5.40 ± 3.8, 2.0 ± 3.1, 1.24 ± 1.1, 2.90 ± 3.3, and 4.03 ± 3.4 mIU/L. There was significant fall (29.1% for FT4, 32.1% for TT4, 77% for TSH, 46% for FT3 and 45% for TT3, p < 0.0001). When area under curve (AUC) TT4 was compared between survivors (n = 87) and nonsurvivors (n = 12), significantly larger AUC was seen in survivors (492.81 ± 158.6) than nonsurvivors (360.75 ± 179.6 p = 0.0125). In survivors >72 hours, AUC TT4 was larger in patients with uneventful postoperative course versus those with postoperative complications (516.48 ± 18.6 vs. 394.78 ± 29.9, p = 0.001). AUC TT4 showed significant inverse correlation with inotropic score and borderline inverse correlation with duration of mechanical ventilation. CONCLUSION Children undergoing surgery under CPB showed significant fall in thyroid hormones. Because TT4 level is modifiable, prophylactic administration of TT4 for improving outcomes needs to be studied further.
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Affiliation(s)
- Sachin Talwar
- Departments of Cardiothoracic and Vascular Surgery, All India Institute of Medical Sciences, New Delhi, India.
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Akçevin A, Alkan-Bozkaya T, Qiu F, Undar A. Evaluation of perfusion modes on vital organ recovery and thyroid hormone homeostasis in pediatric patients undergoing cardiopulmonary bypass. Artif Organs 2011; 34:879-84. [PMID: 21092030 DOI: 10.1111/j.1525-1594.2010.01159.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The objectives of this study were: (i) to evaluate the effects of perfusion modes (pulsatile vs. nonpulsatile) on vital organs recovery and (ii) to investigate the influences of two different perfusion modes on the homeostasis of thyroid hormones in pediatric patients undergoing cardiopulmonary bypass (CPB) procedures. Two hundred and eighty-nine consecutive pediatric patients undergoing open heart surgery for repair of congenital heart disease were prospectively entered into the study and were randomly assigned to two groups: the pulsatile perfusion group (Group P, n = 208) and the nonpulsatile perfusion group (Group NP, n = 81). All patients received identical surgical, perfusional, and postoperative care. Study parameters included total drainage, mean urine output in the intensive care unit (ICU), intubation time, duration of ICU and hospital stay, the need for inotropic support, pre- and postoperative enzyme levels (ALT [alanine aminotransaminase] and AST [aspartate aminotransaminase]), c-reactive protein, lactate, albumin, blood count (leukocytes, hematocrit, platelets), creatinine levels, and thyroid hormones (thyroid stimulating hormone [TSH], FT(3) [free triiodothyronine], FT(4) [free thyroxine]). All patients survived the perioperative and postoperative periods. There were no statistically significant differences in either preoperative or operative parameters between the two groups. Group P, compared to Group NP, required significantly less inotropic support, had a shorter intubation period, higher urine output in ICU, and shorter duration of ICU and hospital stay. Lower lactate levels and higher albumin levels were observed in Group P and there were no significant differences in creatinine, enzyme levels, blood counts, or drainage amounts between two groups. TSH, Total T(3) , Total T(4) , and FT(3) , FT(4) levels were markedly reduced versus their preoperative values in both groups. FT(3) and FT(4) levels were reduced significantly further in the nonpulsatile group both during CPB and at 72 h postoperation. The results of this study confirm our opinion that pulsatile perfusion leads to better vital organ recovery and clinical outcomes in the early postoperative period as compared to nonpulsatile perfusion in pediatric patients undergoing CPB cardiac surgery. The plasma concentrations of thyroid hormones are dramatically reduced during and after CPB, but pulsatile perfusion seems to have a protective effect of thyroid hormone homeostasis compared to nonpulsatile perfusion.
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Affiliation(s)
- Atif Akçevin
- Department of Cardiovascular Surgery, Istanbul Bilim University, Istanbul, Turkey
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Affiliation(s)
- Miriam O Ribeiro
- Department of Biological Science, Biological and Health Science Center, MacKenzie Presbiterian University, Sao Paulo SP 01302, Brazil
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Aslan A, Osmanagaoglu S, Cavolli R, Emiroglu O, Kaya K, Kahraman D, Uymaz OK, Tasoz R, Ozyurda U. Sodium nitroprusside infusion prevents hypothyroidism in patients undergoing coronary artery bypass grafting: a prospective randomized clinical trial. J Cardiovasc Med (Hagerstown) 2010; 11:575-82. [DOI: 10.2459/jcm.0b013e328337d6f5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Thyroid hormones and cardiac arrhythmias. Vascul Pharmacol 2009; 52:102-12. [PMID: 19850152 DOI: 10.1016/j.vph.2009.10.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Accepted: 10/05/2009] [Indexed: 01/09/2023]
Abstract
Thyroid hormone plays an important role in cardiac electrophysiology and Ca2+ handling through both genomic and nongenomic mechanisms of action, while both actions can interfere. Chronic changes in the amount of circulating thyroid hormone due to thyroid dysfunction or systemic disease result in structural, electrophysiological and Ca2+ handling remodeling, while acute changes may affect basal activity of cardiac cells membrane systems. Consequently, long-term or rapid modulation of sarcolemmal ion channels, Ca2+ cycling proteins and intercellular communicating channels by thyroid hormone may affect heart function as well as susceptibility of the heart to arrhythmias. This aspect including pro- and anti-arrhythmic potential of thyroid hormone is highlighted in this review.
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Choi YS, Kwak YL, Kim JC, Chun DH, Hong SW, Shim JK. Peri-operative oral triiodothyronine replacement therapy to prevent postoperative low triiodothyronine state following valvular heart surgery. Anaesthesia 2009; 64:871-7. [DOI: 10.1111/j.1365-2044.2009.05984.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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François M, Delemer B. Quoi de neuf dans le couple thyroïde et cœur en 2008 ? ANNALES D'ENDOCRINOLOGIE 2008; 69 Suppl 1:S37-43. [DOI: 10.1016/s0003-4266(08)73967-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Thyroid hormone has various effects on the cardiovascular system and its effects on cardiac contractility, heart rhythm and vascular function has long been recognized. However, new evidence is emerged on the importance of thyroid hormone in the response of the myocardium to ischaemic stress and cardiac remodelling following myocardial infarction. Based on this new information, this review highlights the role of thyroid hormone in myocardial ischaemia and cardiac remodelling, the possible underlying mechanisms and the potential therapeutic implications. Thyroid hormone or analogs may prove new therapeutic agents for treating ischaemic heart disease.
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Affiliation(s)
- Constantinos Pantos
- Department of Pharmacology, University of Athens, 75 Mikras Asias Avenue, 11527 Goudi, Athens, Greece.
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Lavis VR, Picolos MK, Willerson JT. Endocrine Disorders and the Heart. CARDIOVASCULAR MEDICINE 2007. [DOI: 10.1007/978-1-84628-715-2_111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Bunevicius R, Varoneckas G, Prange AJ, Hinderliter AL, Gintauskiene V, Girdler SS. Depression and thyroid axis function in coronary artery disease: impact of cardiac impairment and gender. Clin Cardiol 2006; 29:170-4. [PMID: 16649727 PMCID: PMC6654096 DOI: 10.1002/clc.4960290409] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Increased rates of depression are reported in coronary artery disease (CAD). In heart disease, depression increases disability, reduces quality of life, and increases mortality. HYPOTHESIS The study was undertaken to examine the relationship between depression and thyroid axis function in patients with CAD. METHODS In all, 73 patients with CAD, consecutively admitted to a cardiac rehabilitation hospital, were assessed for depression using the Hospital Anxiety and Depression scale (HADS). Blood was drawn for assessment of thyroid axis hormones and the N-amino terminal fragment of the pro-B-type natriuretic peptide (NT-pro BNP). RESULTS The patients with CAD with depressive symptoms had a higher prevalence of cardiac failure (p = 0.04), higher NT-pro BNP concentrations (p = 0.02), and lower free triiodothyronine (T3) concentrations (p = 0.04) than patients with CAD but without depressive symptoms. They also showed a strong trend (p = 0.058) toward a higher incidence of the low T3 syndrome. Higher NT-pro BNP concentrations were related to lower total T3 concentrations (r = -0.294, p = 0.011) and to higher reverse T3 concentrations (r = 0.353, p = 0.002). In men, higher scores of depression were related to lower total T3 concentration (r = -0.289, p = 0.034) and to higher NT-pro BNP concentration (r = 0.380, p = 0.005). CONCLUSION These findings suggest that symptoms of depression in patients with CAD are associated with changes in thyroid axis function and with cardiac impairment, especially in men.
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Affiliation(s)
- Robertas Bunevicius
- Institute of Psychophysiology and Rehabilitation, Kaunas University of Medicine, Palanga, Lithuania.
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Abstract
It has been known for decades that the neuroendocrine system can both directly and indirectly influence the developmental and functional activity of the immune system. In contrast, far less is known about the extent to which the immune system collaborates in the regulation of endocrine activity. This is particularly true for immune-endocrine interactions of the hypothalamus-pituitary-thyroid axis. Although thyroid-stimulating hormone (TSH) can be produced by many types of extra-pituitary cells--including T cells, B cells, splenic dendritic cells, bone marrow hematopoietic cells, intestinal epithelial cells, and lymphocytes--the functional significance of those TSH pathways remains elusive and historically has been largely ignored from a research perspective. There is now, however, evidence linking cells of the immune system to the regulation of thyroid hormone activity in normal physiological conditions as well as during times of immunological stress. Although the mechanisms behind this are poorly understood, they appear to reflect a process of local intrathyroidal synthesis of TSH mediated by a population of bone marrow cells that traffic to the thyroid. This hitherto undescribed cell population has the potential to microregulate thyroid hormone secretion leading to critical alterations in metabolic activity independent of pituitary TSH output, and it has expansive implications for understanding mechanisms by which the immune system may act to modulate neuroendocrine function during times of host stress. In this article, the basic underpinnings of the hematopoietic-thyroid connection are described, and a model is presented in which the immune system participates in the regulation of thyroid hormone activity during acute infection.
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Affiliation(s)
- John R Klein
- Department of Diagnostic Sciences, University of Texas Health Science Center at Houston, Room 3.094F, Dental Branch, 6516 MD Anderson Boulevard, 77030, USA.
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Machackova J, Barta J, Dhalla NS. Molecular defects in cardiac myofibrillar proteins due to thyroid hormone imbalance and diabetesThis paper is a part of a series in the Journal's "Made in Canada" section. The paper has undergone peer review. Can J Physiol Pharmacol 2005; 83:1071-91. [PMID: 16462907 DOI: 10.1139/y05-121] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The heart very often becomes a victim of endocrine abnormalities such as thyroid hormone imbalance and insulin deficiency, which are manifested in a broad spectrum of cardiac dysfunction from mildly compromised function to severe heart failure. These functional changes in the heart are largely independent of alterations in the coronary arteries and instead reside at the level of cardiomyocytes. The status of cardiac function reflects the net of underlying subcellular modifications induced by an increase or decrease in thyroid hormone and insulin plasma levels. Changes in the contractile and regulatory proteins constitute molecular and structural alterations in myofibrillar assembly, called myofibrillar remodeling. These alterations may be adaptive or maladaptive with respect to the functional and metabolic demands on the heart as a consequence of the altered endocrine status in the body. There is a substantial body of information to indicate alterations in myofibrillar proteins including actin, myosin, tropomyosin, troponin, titin, desmin, and myosin-binding protein C in conditions such as hyperthyroidism, hypothyroidism, and diabetes. The present article is focussed on discussion how myofibrillar proteins are altered in response to thyroid hormone imbalance and lack of insulin or its responsiveness, and how their structural and functional changes explain the contractile defects in the heart.
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Affiliation(s)
- Jarmila Machackova
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, 351 Tache Avenue, Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, MB R2H 2A6, Canada
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Wyne KL. The role of thyroid hormone therapy in acutely ill cardiac patients. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2005; 9:333-4. [PMID: 16137376 PMCID: PMC1269460 DOI: 10.1186/cc3738] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The presence of a 'low T3 syndrome' in the setting of nonthyroidal illness has long been recognized as the 'euthyroid sick syndrome', with the recommendation to observe and not treat with thyroid hormone replacement therapy. That approach has recently been challenged in the setting of critical cardiac illness. Research demonstrating that thyroid hormone therapy may improve hemodynamic parameters has rekindled interest in the use of thyroid hormone therapy in critical illness. Continued improvements in survival after critical cardiac illness provokes the question of whether thyroid hormone therapy would provide further incremental benefit.
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Affiliation(s)
- Kathleen L Wyne
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
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Tribulova N, Knezl V, Okruhlicova L, Drimal J, Lamosova D, Slezak J, Styk J. L-thyroxine increases susceptibility of adult rats to low K+-induced ventricular fibrillation, and sinus rhythm restoration in old rats. Exp Physiol 2004; 89:629-36. [PMID: 15258117 DOI: 10.1113/expphysiol.2004.027607] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hypokalaemia increases the risk for life-threatening arrhythmias; however, data about interaction with thyroid status are lacking. The aim of this study was to investigate vulnerability of l-thyroxine (T(4))-treated adult and old rats to low K(+)-induced ventricular fibrillation (VF) as well as the ability of the heart to recover sinus rhythm. The experiments were performed on isolated heart preparations using the heart of 4- and 20-month-old female Wistar rats without and with feeding with T(4) 50 microg (100 g day)(-1) over a period of 2 weeks. Perfusion of the isolated heart with oxygenated Krebs-Henseleit solution at constant pressure was followed by perfusion with K(+)-deficient solution until occurrence of VF (< 10 min). After 2 min of sustained VF, the heart was perfused with normal solution for 10 min, during which sinus rhythm was restored. ECG, left ventricular pressure (LVP) and coronary flow were continuously monitored. The results showed that compared with untreated rats, the onset of low K(+)-induced ventricular premature beats was delayed and their number was significantly decreased in both T(4)-treated groups. Nevertheless, VF occurred earlier in T(4)-treated than in non-treated adult rats (6.78 +/- 0.28 vs. 9.59 +/- 0.55 min, P < 0.05), whereas the difference was not significant in aged animals. Furthermore, sinus rhythm appeared earlier in old T(4)-treated rats compared with non-treated rats (7.18 +/- 0.57 vs. 8.94 +/- 0.64 min, P < 0.05), whereas in adult hearts it set in at practically the same time regardless of treatment. In conclusion, our results indicate that administration of a pharmacological dose of T(4) can increase the risk of low K(+)-induced VF in adult but not in old animals; in the latter it even facilitated restoration of sinus rhythm. Moreover, enhanced mechanical function was observed in both adult and old T(4)-treated hearts.
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Affiliation(s)
- Narcis Tribulova
- Institute for Heart Research, Slovak Academy of Sciences, Dubravska cesta 9, 840 05 Bratislava 45, PO Box 104, Slovak Republic.
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