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Heart Rhythm 2019 Mar 20. Epub 2019 Mar 20.

Division of Pediatric Endocrinology and Metabolism, Mayo Clinic, Rochester, Minnesota. Electronic address:

Background: Heart Rhythm Society guidelines recommend obtaining thyroid function tests (TFTs) at amiodarone initiation and every six months thereafter in adults, with no specific pediatric recommendations. Untreated hypothyroidism in young children negatively affects brain development and somatic growth, yet the optimal screening frequency for pediatric patients remains unclear and limited data exists on pediatric amiodarone-induced thyroid dysfunction.

Objective: We aim to describe the patterns of amiodarone-induced thyroid dysfunction in pediatric patients. Read More

Presse Med 2018 Sep 28;47(9):746-756. Epub 2018 Sep 28.

CHU Clermont-Ferrand, service d'endocrinologie, diabétologie et maladies métaboliques, 63003 Clermont-Ferrand, France; Laboratoire GReD : UMR université Clermont Auvergne-CNRS 6293, Inserm U1103, BP 10448, 63177 Aubiere, France.

Amiodarone, a benzofuranic iodine-rich pan antiarrhythmic drug, is frequently associated with thyroid dysfunction. This side effect is heterogeneous and unpredicted, motivating regular evaluation of thyroid function tests. In contrary to hypothyroidism, amiodarone-induced thyrotoxicosis (AIT) is a challenging situation owing to the risk of deterioration of the general and cardiac status of such debilitating patients. Read More

Pediatr Cardiol 2018 Dec 21;39(8):1707-1716. Epub 2018 Sep 21.

Hospital for Children and Adolescents, University Leipzig, Liebigstr. 20a, 04103, Leipzig, Germany.

Amiodarone-induced hyperthyroidism is a known side effect of amiodarone treatment. In the pediatric population, long-term amiodarone treatment is rarely indicated because of its severe side effects including thyroid function impairment. Treatment is therefore restricted to therapy-resistant arrhythmias. Read More

Congenit Heart Dis 2018 Nov 21;13(6):944-951. Epub 2018 Sep 21.

Department of Cardiology, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia.

Objective: Amiodarone is a highly effective antiarrhythmic therapy, however its toxicity profile often limits treatment. This is particularly relevant in adults with congenital heart disease (CHD), who are often young and in whom other antiarrhythmic agents commonly fail or are contraindicated. We sought to determine incidence and predictors of adverse effects caused by amiodarone in adult CHD (ACHD). Read More

Heart Lung 2018 Jul - Aug;47(4):429-431. Epub 2018 May 21.

Department of Cardiology, New York Medical College, St. Joseph Medical Center, 703 Main Street, Paterson, NJ 07503, USA.

Amiodarone is a benzofuran derivative that contains 37% iodine by weight and is structurally similar to the thyroid hormones. Amiodarone has a complex effect on the thyroid gland, ranging from abnormalities of thyroid function tests to overt thyroid dysfunction, with either thyrotoxicosis or hypothyroidism. Myxedema coma secondary to amiodarone use has been rarely reported in the literature. Read More

Exp Clin Endocrinol Diabetes 2018 Jun 20;126(6):333-341. Epub 2018 Mar 20.

Department of Endocrinology, Diabetes & Metabolism, University Hospitals of Morecambe Bay NHS Foundation Trust, United Kingdom, LA1 4RP.

Amiodarone is one of the most commonly prescribed antiarrhythmic agents in clinical practice owing to its efficacy, even with high toxicity profile. The high iodine content and the prolonged biological half-life of the drug can result in thyroid dysfunction in a high proportion of patients treated with amiodarone even after cessation of amiodarone. Both hypothyroidism and hyperthyroidism are common side effects that mandate regular monitoring of patients with thyroid function tests. Read More

Pediatr Cardiol 2018 Jun 9;39(5):1016-1022. Epub 2018 Mar 9.

Department of Pediatric Cardiology, Sakakibara Heart Institute, 3-16-1 Asahi-cho, Fuchu, Tokyo, 183-0003, Japan.

Amiodarone (AMD) is a class III anti-arrhythmic drug that is highly effective for tachyarrhythmia treatment. AMD is widely used in adults with congenital heart disease (CHD); however, higher doses of AMD (> 200 mg/day) can cause various non-cardiac side effects. The purpose of this study was to assess the efficacy, safety, and adverse events of low-dose AMD (≤ 200 mg/day) for tachyarrhythmia in patients with CHD. Read More

J Community Hosp Intern Med Perspect 2017 14;7(6):369-371. Epub 2017 Dec 14.

Department of Internal Medicine, Tower Health: Reading Hospital, Reading, PA, USA.

Amiodarone is an effective medication used in the treatment of several different arrhythmias. Its most well-known adverse effects include pulmonary fibrosis, thyroid dysfunction, and hepatotoxicity. A less common side effect is acute pancreatitis. Read More

Adv Exp Med Biol 2018 ;1067:239-253

Cardiology Unit, Cardiothoracic Department, Policlinic University Hospital, Bari, Italy.

Among comorbidity in chronic heart failure (CHF), dysthyroidism represents a relevant problem especially in the ageing CHF patients worldwide. Thyroid greatly affects many cardiovascular activities and its dysfunction may worsen a CHF condition. In particular, hypothyroidism has a relative high prevalence in patients with heart failure and it plays a key role in influencing CHF onset, progression and prognosis. Read More

Curr Radiopharm 2017 Nov;10(3):146-154

Ion Chiricuta Institute of Oncology, Cluj-Napoca, Romania.

Background And Objective: The use of amiodarone for the treatment of ventricular and supraventricular dysrhythmias brings in organism an increased amount of iodine, interfering with thyroid function. If the treatment needs to be interrupted, iodine remains at abnormal levels for months or even years. The aim of the study was to review the literature regarding the optimal tests for early diagnostic and to analyze the role of nuclear medicine tests in the differential and correct assessment of the amiodarone-induced thyroid pathology. Read More

Eur J Endocrinol 2017 Jul 19;177(1):9-14. Epub 2017 Apr 19.

Department of Internal MedicineDivision of Endocrinology.

Objective: Amiodarone is used for the maintenance of sinus rhythm in patients with arrhythmias, but thyroid dysfunction (amiodarone-induced thyrotoxicosis (AIT) or amiodarone-induced hypothyroidism (AIH)) is a common adverse effect. As the onset of AIT and AIH may be unpredictable, the value of long-term regular monitoring of amiodarone treated patients for thyroid dysfunction is still uncertain.

Design: We retrospectively documented the frequency at which overt thyroid dysfunction was preceded by subclinical thyroid dysfunction. Read More

G Ital Cardiol (Rome) 2017 Mar;18(3):219-229

Unità di Endocrinologia, Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi, Pisa.

Amiodarone-induced thyroid dysfunction occurs in about 15-20% of patients under amiodarone therapy. Amiodarone-induced hypothyroidism (AIH) can develop in patients with an apparently normal thyroid gland or in those with an underlying chronic autoimmune thyroiditis. On a clinical ground, AIH is not challenging and can be easily treated with L-thyroxine therapy. Read More

J Clin Pharm Ther 2017 Apr 13;42(2):189-194. Epub 2016 Dec 13.

School of Pharmacy, University of Otago, Dunedin, New Zealand.

What Is Known And Objective: Prescription sequence symmetry analyses (PSSA) is a ubiquitous tool employed in pharmacoepidemiological research to predict adverse drug reactions (ADRs). Several studies have reported the advantage of PSSA as a method that can be applied to a large prescription database with computational ease. The objective of this study was to validate New Zealand (NZ) prescription database as a potential source for identifying ADRs using the PSSA method. Read More

Continuum (Minneap Minn) 2016 Dec;22(6, Muscle and Neuromuscular Junction Disorders):1815-1828

Purpose Of Review: This article discusses the clinical features, pathophysiology, and management of toxic and endocrine myopathies.

Recent Findings: Early detection and expeditious correction of metabolic disturbances in endocrinopathies such as Cushing syndrome, thyroid and parathyroid diseases, and acromegaly can minimize and prevent neurologic complications including myopathy. Recently proposed mechanisms of injury in patients with critical illness myopathy include inhibition of protein synthesis, mitochondrial dysfunction, disruption of the ubiquitin-proteasome system, oxidative stress, and disruption of intramuscular calcium homeostasis, which can cause a myosin-loss myopathy. Read More

J Arrhythm 2016 Dec 5;32(6):474-480. Epub 2016 May 5.

Division of Clinical Drug Informatics, School of Pharmacy, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-0818, Japan.

Background: Amiodarone is associated with a number of significant adverse effects, including elevated transaminase levels, pulmonary fibrosis, arrhythmia, and thyroid dysfunction. Although thyroid dysfunction is considered to be a common and potentially serious adverse effect of amiodarone therapy, the exact pathogenesis remains unknown because of its complex manifestations. Therefore, the prevalence of, and risk factors for, amiodarone-induced thyroid dysfunction in Japanese patients were investigated in the present study. Read More

Vnitr Lek Fall 2016;62(9 Suppl 3):92-98

Cardiovascular system is essentially affected by thyroid hormones by way of their genomic and non-genomic effects. Untreated overt thyroid dysfunction is associated with higher cardiovascular risk. Although it has been studied more than 3 decades, in subclinical thyroid dysfunction the negative effect on cardiovascular system is much more controversial. Read More

J Eval Clin Pract 2017 Feb 12;23(1):108-113. Epub 2016 Aug 12.

Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.

Rationale, Aims And Objectives: Baseline thyroid function testing and regular follow-up of thyroid function under amiodarone usage was recommended by guidelines. Little is known about the status of amiodarone monitoring in real-world clinical care in Taiwan. The objective was to determine the rate of thyroid monitoring and to assess the clinical and physicians' characteristics associated with adequate monitoring in a tertiary referral centre for arrhythmia. Read More

Cardiol J 2016 14;23(4):416-21. Epub 2016 Jun 14.

Department of Cardiology, The Affiliated Hospital of Qingdao Univer sity, Qingdao, China.

Background: Amiodarone is an antiarrhythmic drug that is frequently used to control atrial fibrillation (AF). Many patients with AF are afraid of the risk of ablation and take amiodar-one, some patients develop amiodarone-induced thyrotoxicosis (AIT). The purpose of the study was to investigate the safety and efficacy of early radiofrequency catheter ablation in patients with paroxysmal AF complicated with AIT. Read More

Rev Med Suisse 2016 Apr;12(515):804-9

The principle sources of iodine overload, amiodarone and radiologic contrast media, are frequently used in modern medicine. The thyroid gland exerts a protective effect against iodine excess by suppressing iodine internalization into the thyrocyte and iodine organification, the Wolff-Chaikoff effect. Insufficiency of this effect or lack of escape from it leads to hypo- or hyperthyroidism respectively. Read More

Eur J Intern Med 2016 Sep 26;33:36-41. Epub 2016 Apr 26.

Department of Cardiology, Section 2013, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; The Danish National Research Centre for Cardiac Arrhythmia, Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.

Background: Amiodarone is known to affect the thyroid, but little is known about thyroid recovery after short-term amiodarone treatment.

Objectives: We aimed to evaluate the impact of 8weeks of amiodarone treatment on thyroid function in patients with atrial fibrillation (AF) undergoing catheter ablation in a randomised, double-blind clinical trial.

Methods: 212 patients referred for AF ablation at two centres were randomized to 8weeks of oral amiodarone or placebo. Read More

Ther Clin Risk Manag 2016 4;12:505-13. Epub 2016 Apr 4.

Department of Endocrinology, Metabolism and Internal Medicine, Poznan, Poland.

Aim: This study aims to explore and compare the efficacy of radioiodine treatment (RIT) in hyperthyroid and euthyroid patients who have been treated with amiodarone (AM) in the past or are currently undergoing AM treatment. Clinical observation of a group of patients with amiodarone-induced hypothyroidism during a 12-month follow-up period was used for comparison.

Design: This was a observational, two-centered study. Read More

Endocr Pract 2016 Aug 4;22(8):974-9. Epub 2016 Apr 4.

Objective: Overt hyperthyroidism and methimazole (MMI) treatment are frequently associated with abnormal liver function tests (LFTs). We describe the serial changes of LFTs in MMI-treated hyperthyroid patients.

Methods: We retrospectively analyzed all 77 patients presenting with newly diagnosed overt hyperthyroidism (59 Graves diseases, 11 toxic nodular goiters, 4 toxic adenomas, 3 amiodarone-induced thyrotoxicosis) between 2012 and 2014. Read More

Lancet 2016 Aug 30;388(10047):906-918. Epub 2016 Mar 30.

Endocrine Unit, Fondazione IRCCS Cà Granda, Milan, Italy (S De Leo MD); Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy (S De Leo); and Section of Endocrinology, Diabetes and Nutrition, Boston University School of Medicine, Boston, MA, USA (S De Leo, S Y Lee MD, Prof L E Braverman MD).

Hyperthyroidism is characterised by increased thyroid hormone synthesis and secretion from the thyroid gland, whereas thyrotoxicosis refers to the clinical syndrome of excess circulating thyroid hormones, irrespective of the source. The most common cause of hyperthyroidism is Graves' disease, followed by toxic nodular goitre. Other important causes of thyrotoxicosis include thyroiditis, iodine-induced and drug-induced thyroid dysfunction, and factitious ingestion of excess thyroid hormones. Read More

Pharmacol Rep 2016 Apr 15;68(2):490-4. Epub 2015 Dec 15.

Department of Internal Medicine and Clinical Pharmacology, Medical University of Silesia, Katowice, Poland.

Background: Chronic metformin treatment was found to reduce elevated thyrotropin levels. Amiodarone treatment is associated with a range of effects in thyroid function from mild derangements to overt thyroid dysfunction. No previous study has investigated the effect of metformin on hypothalamic-pituitary-thyroid axis activity in patients with amiodarone-induced hypothyroidism. Read More

Pol Merkur Lekarski 2016 Jan;40(235):46-52

Medical University of Lodz. Poland: Department of Electrocardiology, Chair of Cardiology and Cardiac Surgery.

Amiodarone is an antiarrhythmic drug frequently used in everyday clinical practice. Its mechanism of action involves the interaction with many receptors, including those in the cardiac conduction system. Amiodarone usefulness is protect in the treatment of a variety of tachyarrhythmias, both benign and life-threatening. Read More

Curr Probl Cardiol 2016 Feb 23;41(2):65-92. Epub 2015 Apr 23.

Thyroid hormones have an intimate relationship with cardiac function. Some of the most significant clinical signs and symptoms of thyroid disease are the cardiac manifestations. In both hypothyroidism and hyperthyroidism, the characteristic physiological effects of thyroid hormone can be understood from the actions at the molecular and cellular level. Read More

Lijec Vjesn 2015 May-Jun;137(5-6):181-8

Amiodarone is a benzofuran derivative that contains up to 40% of iodine. Amiodarone is used for treatment and prevention of life threatening supraventricular and ventricular tachyarrhythmias. The effects on thyroid gland vary from abnormalities in thyroid function tests to overt amiodarone induced hypothyroidism (AIH) and thyrotoxicosis (AIT). Read More

Zhonghua Er Ke Za Zhi 2015 Mar;53(3):214-9

Objective: Ectopic atrial tachycardia (EAT) is a common type of supraventricular tachycardia in pediatric population, and it can be resistant to antiarrhythmic drugs and lead to tachycardia induced cardiomyopathy (TIC) if not properly managed. This study assessed the clinical course and response to treatment of EAT in children.

Method: A retrospective review included 144 children at the First Hospital of Tsinghua University diagnosed with EAT from January 2009 to April 2014. Read More

Circ J 2015 27;79(8):1828-34. Epub 2015 May 27.

Department of Pediatric Cardiology, Tokyo Women's Medical University.

Background: Although amiodarone (AMD)-induced thyroid dysfunction (AITD) is an important complication of AMD therapy, little is known about AITD in adult Japanese patients with congenital heart disease (CHD).

Methods And Results: We retrospectively studied 131 adult patients with CHD who were on low-dose AMD (median, 150 mg/day). The median patient age was 28 years, and the median follow-up was 44 months. Read More

Endokrynol Pol 2015 ;66(2):176-86

Department of Endocrinology, Jagiellonian University, Medical College, Krakow, Poland.

Amiodarone, a benzofuranic iodine-rich antiarrhythmic drug, causes thyroid dysfunction in 15-20% of cases. Amiodarone can cause both hypothyroidism (AIH, amiodarone-induced hypothyroidism) and thyrotoxicosis (AIT, amiodarone-induced thyrotoxicosis). AIH is treated by L-thyroxin replacement and does not need amiodarone discontinuation. Read More

Rev Med Chir Soc Med Nat Iasi 2014 Oct-Dec;118(4):959-64

University of Medicine and Pharmacy Grigore T. Popa - Iaşi, Department of Medical Specialties (I).

Aim: the analysis of therapeutic approach in patients with basic heart condition and amiodarone induced thyroid dysfunction--correlations with the evolution and prognosis.

Material And Methods: The study included 215 patients, 90 men and 125 women aged between 35 and 87, with different cardiac pathologies hospitalized in the Cardiology Clinic between 2004-2014, who received amiodarone treatment, in most cases for prophylaxis of various arrhythmias, both supraventricular and ventricular. During the evolution, these patients have developed amiodarone-induced thyroid dysfunction (hypo- or hyper function). Read More

Medicina (B Aires) 2014 ;74(6):481-92

Dirección Médica Química Montpellier SA, Buenos Aires, Argentina. E-mail:

The term thyroiditis comprises a group of thyroid diseases characterized by the presence of inflammation, including autoimmune and non-autoimmune entities. It may manifest as an acute illness with severe thyroid pain (subacute thyroiditis and infectious thyroiditis), and conditions in which the inflammation is not clinically evident evolving without pain and presenting primarily thyroid dysfunction and/or goiter (drug-induced thyroiditis and Riedel thyroiditis). The aim of this review is to provide an updated approach on non-autoimmune thyroiditis and its clinical, diagnostic and therapeutic aspects. Read More

BMJ Case Rep 2014 Oct 27;2014. Epub 2014 Oct 27.

Walsall Hospitals Healthcare NHS Trust, Walsall, UK.

A 69-year-old man presented with a 6-week history of shortness of breath on exertion, unintentional weight loss, altered bowel habits and lethargy. He was diagnosed with atrial fibrillation 2 years previously and started on amiodarone and warfarin. He subsequently reverted to sinus rhythm and his medication was stopped 1 year prior to presentation. Read More

Rev Med Chir Soc Med Nat Iasi 2014 Apr-Jun;118(2):359-63

Aim: The purpose of this study was to investigate the prevalence and the clinical-evolutionary implications of thyroid damage in patients treated with amiodarone in the Cardiology Clinic of the "Sf. Spiridon" University Hospital of Iasi.

Material And Methods: The study included a group of 215 patients, 90 men and 125 women with ages between 35 and 87, hospitalized in the Cardiology Clinic between 2004 and 2014, who received amiodarone treatment, in most cases for the prophylaxis of various arrhythmias, both supra-ventricular and ventricular. Read More

Int J Stem Cells 2013 Nov;6(2):113-20

Department of Histology, Faculty of Medicine, Beni-Suef University, Cairo, Egypt.

Background And Objectives: Amiodarone (AM), one of the most commonly prescribed antiarrhythmics, is frequently associated with thyroid dysfunction. Green tea extract (GTE) supplementation would attenuate oxidative stress and activate progenitor cells. However, the potential toxicity of GTE on various organs when administered at high doses has not been completely investigated. Read More

Open Cardiovasc Med J 2013 29;7:122-6. Epub 2013 Nov 29.

Department of Pharmacology & Clinical Pharmacy, College of Medicine & Health Sciences, Sultan Qaboos University, Muscat, Oman ; Gulf Health Research, Muscat, Oman.

Objective: To determine the incidence and pattern of thyroid dysfunction (TD) in patients on chronic amiodarone therapy.

Methods: A retrospective study which evaluated 59 patients who had received amiodarone therapy regularly for at least 12 months from a period of 3 years from October 2007 to October 2010. The patients were followed-up at the cardiac clinic at Sultan Qaboos University Hospital, Muscat, Oman. Read More

Rev Med Chir Soc Med Nat Iasi 2013 Apr-Jun;117(2):375-9

Department of Cardiology, Faculty of Medicine, University of Medicine and Pharmacy "Grigore T. Popa" - Iasi.

Discovered in 1961 by Tondeur and Binon, two Belgian chemists, amiodarone was widely used, especially in Europe, initially as an antianginal agent, and later as an antiarrhythmic one (following the experiments conducted at the University of Oxford by Dr. Bramah Singh). Thus, the role of amiodarone was reconsidered, becoming, together with Sotalol, a class III antiarrhythmic--a group characterized by the action of extending the potassium channels refractory period. Read More

Endocr Pract 2014 May;20(5):490-9

Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota.

Objective: To report 3 cases of reversible hypothyroidism-induced kidney dysfunction and review the interaction between these commonly encountered, yet seemingly disparate, conditions.

Methods: We describe the clinical course and laboratory and physical findings of 3 patients who presented with kidney dysfunction that improved after initiating thyroid hormone replacement therapy. We also review similar cases in the literature and discuss the pathophysiologic mechanisms. Read More

J Clin Apher 2014 Jun 22;29(3):168-70. Epub 2013 Nov 22.

Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.

Introduction: Amiodarone is associated with thyroid dysfunction and life-threatening thyrotoxicosis. In medically refractory cases, or where medical therapy is contraindicated, thyroidectomy may be required. To decrease perioperative thyroid storm and to reduce overall surgical risk, apheresis may be considered preoperatively to restore euthyroidism. Read More

J Intensive Care Med 2015 May 24;30(4):179-85. Epub 2013 Sep 24.

Department of Medicine, NYU School of Medicine, New York, NY, USA.

Amiodarone is an effective medication for the treatment of cardiac arrhythmias. Originally developed for the treatment of angina, it is now the most frequently prescribed antiarrhythmia drug despite the fact that its use is limited because of potential serious side effects including adverse effects on the thyroid gland and thyroid hormones. Although the mechanisms of action of amiodarone on the thyroid gland and thyroid hormone metabolism are poorly understood, the structural similarity of amiodarone to thyroid hormones, including the presence of iodine moieties on the inner benzene ring, may play a role in causing thyroid dysfunction. Read More

Pol Merkur Lekarski 2013 Jul;35(205):5-9

Uniwersytet Medyczny im. Katedra Endokrynologii, Przemiany Materii i Chorób Wewnetrznych.

Amiodarone is a benzofuranic iodine-rich antiarrhythmic drug used in the treatment of severe tachyarrhythmias, especially ventricular. Drug causes many adverse effects including thyroid disorders in 14-18% of patients: amiodarone induced thyrotoxicosis type I and type II (AIT I, AIT II) and amiodarone induced hypothyroidism (AIH). AIT occurs more frequently in geographical areas with low iodine intake, whereas AIH is more frequent in iodine-sufficient areas. Read More

Korean J Gastroenterol 2013 Jul;62(1):59-63

Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.

Amiodarone is a di-iodated benzofuran derivative that is commonly used to treat patients with various cardiac arrhythmias. It is associated with side effects that involve the liver, thyroid, and other organs. Approximately 1-3% of patients treated with amiodarone suffer from symptomatic liver disease. Read More

Drugs Aging 2013 Aug;30(8):593-601

Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA.

Atrial fibrillation (AF) is the most common arrhythmia in older adults with a prevalence of 9 % in adults aged 80 years or older. AF patients have a five times greater risk of developing stroke than the general population. Using anticoagulants for stroke prevention in the elderly becomes a challenge because both stroke and bleeding complications increase with age. Read More

J Cardiovasc Electrophysiol 2013 Aug 9;24(8):888-93. Epub 2013 Apr 9.

Department of Electrophysiology, Almazov Federal Heart, Blood and Endocrinology Centre, Saint-Petersburg, Russian Federation.

Introduction: Many patients with atrial fibrillation (AF) receive amiodarone. Amiodarone-induced hyperthyroidism (AIH) may develop as a complication. We hypothesized that pulmonary vein (PV) isolation in patients with paroxysmal AF and history of AIH may yield a lower success rate. Read More

Mol Cell Biochem 2013 Jul 27;379(1-2):97-105. Epub 2013 Mar 27.

Department of Pharmacology, University of Athens, Athens, Greece.

Thyroid hormone receptor α1 (TRα1) is shown to be critical for the maturation of cardiomyocytes and for the cellular response to stress. TRα1 is altered during post ischemic cardiac remodeling but the physiological significance of this response is not fully understood. Thus, the present study explored the potential consequences of selective pharmacological inhibition of TRα1 on the mechanical performance of the post-infarcted heart. Read More

Eur J Cardiothorac Surg 2013 Sep 1;44(3):573-4. Epub 2013 Mar 1.

Department of Cardiopulmonary Transplantation, Texas Heart Institute at St Luke's Episcopal Hospital, Houston, TX 77225-0345, USA.

The HeartMate II is a continuous-flow left ventricular assist device that can be explanted from patients after cardiac recovery. We implanted a HeartMate II in a 21-year-old man who had idiopathic cardiomyopathy. A year later, he developed thyrotoxicosis, presumably secondary to amiodarone administered for ventricular fibrillation. Read More

Arq Bras Endocrinol Metabol 2013 Feb;57(1):71-8

Serviço de Medicina Interna dos Hospitais de Universidade de Coimbra, Faculdade de Medicina, Universidade de Coimbra, Coimbra, Portugal.

Although most patients remain clinically euthyroid, some develop amiodarone-induced hyperthyroidism (HPEAI) or hypothyroidism (HPOAI). The authors present a retrospective analysis of ten patients with amiodarone-induced thyroid dysfunction. Six patients were female and mean amiodarone intake was 17. Read More

Rev Med Suisse 2012 Nov;8(362):2175-6, 2178-80

Service de médecine interne générale, HUG, 1211 Geneve 14.

Amiodarone, an iodine-rich drug, results in mild disturbances of thyroid function in most patients and in thyroid dysfunction in approximately 20% of them. Hypothyroidism, mainly found in countries without iodine deficiency, is substituted with levothyroxine and does not need amiodarone to be discontinued. Hyperthyroidism, commonly found in areas of iodine deficiency, is more complex and usually motivates discontinuation of amiodarone. Read More

Nihon Rinsho 2012 Nov;70(11):1958-64

Internal Medicine II, Kansai Medical University.

Various drugs may cause thyroid dysfunction. The drugs which may cause thyrotoxicosis include interferon, molecular-targeted agents, amiodarone, thyroid hormone itself and so on. Those which cause hypothyroidism include anti-thyroid drugs, lithium and iodine etc. Read More

Eur J Endocrinol 2012 Nov 6;167(5):609-18. Epub 2012 Sep 6.

Department of Clinical and Molecular Endocrinology and Oncology, University of Naples Federico II, Italy.

Context: Heart failure (HF) is a major cause of morbidity and mortality in Europe and in the United States. The aim of this review article was to assess the results of the prospective studies that evaluated the risk of HF in patients with overt and subclinical thyroid disease and discuss the mechanism of this dysfunction.

Evidence Acquisition: Reports published with the following search terms were searched:, thyroid, hypothyroidism, hyperthyroidism, subclinical hyperthyroidism, subclinical hypothyroidism, levothyroxine, triiodothyronine, antithyroid drugs, radioiodine, deiodinases, clinical symptoms, heart rate, HF, systolic function, diastolic function, systemic vascular resistance, endothelial function, amiodarone and atrial fibrillation. Read More