Hyperthyroidism and pulmonary hypertension

Symptomatic and severe pulmonary hypertension due to hyperthyroidism

Hyperthyroidism has been recognised as the cause of secondary pulmonary hypertension (PH). However, several studies have reported that most PH cases due to hyperthyroidism are asymptomatic and not severe. Here, we report the case of a woman in her 30s with symptomatic and severe PH due to hyperthyroidism. She presented with a 2-month history of dyspnoea on exertion, palpitation and lower-extremity oedema. Echocardiography showed severe PH with estimated pulmonary arterial systolic pressure (ePASP) of 62 mm Hg. The diagnostic work-up showed severe PH due to hyperthyroidism. After treatment for hyperthyroidism, improvement of thyroid function contributed to a decrease in ePASP to 30 mm Hg. Similar to the present case, PH due to hyperthyroidism generally improves with the treatment of hyperthyroidism. Therefore, we must not overlook hyperthyroidism as a cause of PH and diagnose and start treatment for PH-causing hyperthyroidism at an early stage.

The clinical characteristics and outcomes of patients with pulmonary hypertension in association with hyperthyroid state: A systematic review

BACKGROUND

Pulmonary hypertension (PHTN) may occur in thyroid disorders, especially in hypothyroidism. However, there is increasing evidence of PHTN in hyperthyroidism (HTH). The etiology, clinical course, management, and factors associated with outcomes of PHTN in the setting of HTH are unascertained. This systematic review consolidates available evidence on patients with HTH who developed PHTN.

METHODS

We conducted a systematic review on English articles from PubMed, Scopus, and Google Scholar reporting PHTN in patients with hyperthyroidism. Data were analyzed and reported in Microsoft Excel 2020, SPSS version 26, and Jamovi version 1.2.

RESULTS

We identified 589 patients with PHTN in the setting of HTH. Etiologies included Grave disease 66.7%), toxic multinodular goiter (TMNG) (16.8%), drug-induced HTH (0.3%), thyroiditis(0.8%), and toxic adenoma(0.1%). Most patients did not receive any specific management for PHTN and were managed by antithyroid treatment (97.4%). Outcomes of PHTN were reported in 181 patients, with a 94% recovery rate. Pulmonary artery pressures (PAP) before and after HTH management ranged from 22.5 to 75 mm Hg and from 24 to 50 mm Hg, respectively. Outcome analysis performed on data from case reports and series with individually identifiable data revealed a 67.6% female preponderance. An estimated 73.5% of the patients had PHTN at the initial presentation of HTH, which was associated with a better resolution rate of PHTN(OR: 12, P-value: 0.048). TRAB was positive in 47% patients with no clinical difference in outcomes. antiTG AB was reported positive in 29.4%, all of whom had an improvement, compared to an 83.3% improvement rate in those with negative antiTG AB. Various etiologies and treatments did not have any significant differences in the outcome of PHTN.

CONCLUSIONS

PHTN can be present at the initial diagnosis of HTH, which is associated with better outcomes of PHTN. There is a clear female preponderance in the development of PHTN. However, resolution rates seem to be better in males. Although TRAB is associated with the development of PHTN, it does not seem to affect the outcomes. PHTN in patients with HTH does not need any specific management, with >90% resolution with antithyroid therapy. Whether any specific antithyroid therapy has a better outcome in PHTN needs to be explored prospectively.

The Role of Thyroid Disorders, Obesity, Diabetes Mellitus and Estrogen Exposure as Potential Modifiers for Pulmonary Hypertension

Pulmonary hypertension (PH) is a progressive disorder characterized by a chronic in-crease in pulmonary arterial pressure, frequently resulting in right-sided heart failure and potentially death. Co-existing medical conditions are important factors in PH, since they not only result in the genesis of the disorder, but may also contribute to its progression. Various studies have assessed the impact of thyroid disorders and other endocrine conditions (namely estrogen exposure, obesity, and diabetes mellitus) on the progression of PH. The complex interactions that hormones may have with the cardiovascular system and pulmonary vascular bed can create several pathogenetic routes that could explain the effects of endocrine disorders on PH development and evolution. The aim of this review is to summarize current knowledge on the role of concomitant thyroid disorders, obesity, diabetes mellitus, and estrogen exposure as potential modifiers for PH, and especially for pulmonary arterial hypertension, and to discuss possible pathogenetic routes linking them with PH. This information could be valuable for practicing clinicians so as to better evaluate and/or treat concomitant endocrine conditions in the PH population.

Characteristics and Risk Factors of Pulmonary Hypertension in Patients With Hyperthyroidism

OBJECTIVE

This study aimed to comprehensively assess the characteristics and risk factors of hyperthyroidism with pulmonary hypertension (PH).

METHODS

This was a retrospective cross-sectional analysis of 315 consecutive patients with hyperthyroidism admitted to the endocrinology department of Tongji Hospital from February 2016 to December 2017. PH was defined as a pulmonary arterial systolic pressure above 35 mm Hg measured by echocardiography.

RESULTS

Among the 315 patients, 208 were females, the median age was 42 (30-51) years, and the median disease duration was 12 (3-48) months. Thirty-five percent (111/315) of patients were identified with PH. Patients with hyperthyroidism and PH showed significantly higher serum concentrations of free thyroxine (FT4), free triiodothyronine, thyroid receptor antibodies, total bilirubin (TB), direct and indirect bilirubin, lower serum levels of hemoglobin and creatinine, and more severe cardiac load (P < .05 for each) compared with patients without PH. Levels of serum FT4, free triiodothyronine, thyroid receptor antibodies, and thyroid peroxidase antibody were different among groups of patients with different levels of pulmonary arterial systolic pressure (P < .05 for each). Multivariate logistic regression analysis indicated that serum FT4 (odds ratio, 1.02; 95% CI, 1.01-1.04; P = .004) and TB (OR, 1.03; 95% CI, 1.00-1.06; P = .030) were independent risk factors for PH in patients with hyperthyroidism.

CONCLUSION

Elevated serum FT4 and TB levels may be independent risk factors for PH in patients with hyperthyroidism and valuable indicators for the identification and treatment of patients with PH and hyperthyroidism.

[Instrumental and laboratory parameters of myocardial function in adult patients with autoimmune polyglandular syndrome type 2, 3]

BACKGRAUND

Аutoimmune polyglandular syndrome (APS) it is characterized by damage to two or more endocrine glands, which eventually results in the hormonal failure. Some clinical studies describe the development of myocardial lesion in the setting of combined autoimmune endocrine pathology. In Russia the myocardial condition in adult patients with APS types 2 and 3 was examined for the first time.

AIM

To evaluate the structure and functional state of the myocardium according to magnetic resonance imaging (MRI), to analyze changes in the spectrum of specific antiheart autoantibodies and markers of heart lesion in patients with APS types 2 and 3.

MATERIALS AND METHODS

50 patients with APS types 2, 3 were studied. 45 of them were performed with delayed contrast heart MRI. All 50 patients were tested for IgG antibodies to heart muscle antigens by indirect enzymatic immunoassay (EIA), for troponin I and natriuretic peptide by chemiluminescence immunoassay (CLIA), for creatine phosphokinase (CPK) by NAC (N - acetyl-L-cysteine), and for C-reactive protein (CRP) by immunoturbidimetry.

RESULTS

According to the results of heart MRI (n=45), 91% showed signs of functional changes in the left ventricular (LV) myocardium without any signs of myocarditis. 38 of 45 examined patients had deviation of 2 or more indicants of the LV functional state, MEF 68.9±6.6%, IUMm - 86 [75; 99] g, IUSV - 60.9 [50; 66] ml, IUEDVi - 52 [44; 59] ml/m2 , IUESVi - 17 [15.3; 18] ml/m2 , IUESV - 26 [23; 31] ml, IUEDV - 85 [70; 92] ml. 1 patient (2%) had positive result according to the determination of antibodies (AB) to heart muscle antigens (AG). Troponin 1 indicants did not exceed the reference values. The level of CPK exceeded the reference values in 3 patients (6%), an increase of CRP, NT-proBNP was observed in 7 patients (14%), and a combined increase was observed in 1 case.

CONCLUSIONS

We obtained MRI data indicating functional changes in the myocardium in patients with APS types 2 and 3. The autoimmune cause of these changes according to the results of determining of antiheart antibodies was not confirmed in most of the examined patients, the indicants of «damage» to the myocardium (troponin 1 and NT-proBNP) did not deviate from the reference range.

The Association of Autoantibodies in Hyperthyroid Heart Disease Combined with Pulmonary Hypertension

Hyperthyroidism is a clinical state that results from increased thyroid hormone levels which has a significant impact on cardiac function and structure. Graves' disease is the most common cause of hyperthyroidism in iodine-replete areas. Hyperthyroid heart disease may be associated with pulmonary hypertension in patients who have overt hyperthyroidism. To investigate the association of pulmonary hypertension induced by hyperthyroid heart disease and autoantibody, one hundred and one cases with hyperthyroid heart disease who were consecutively admitted to the inpatient department of endocrinology and metabolism of the Shandong Provincial Hospital between November 2014 and April 2018 were collected and analyzed statistically. According to the Independent samples T-test, variance analysis, chi-square test, Pearson linear correlation analysis, and logistic regression, there was a good correlation between pulmonary artery systolic pressure and thyroid stimulating hormone (TSH) and receptor antibodies (TRAb) (r = 0.264, P=0.025) (OR = 1.037, P=0.029), but there was no significant correlation between the pulmonary artery systolic pressure and other thyroid-related parameters (FT3, FT4, TSH, anti-TPO, and anti-TG). Based on variance analysis, PASP rose as the level of TRAb gets higher. What is more, patients with HHD combined with PH showed a significantly higher serum level of TRAb; moreover, serum TRAb concentration was remarkably correlated with the PASP level. Therefore, TRAb participates in the process of pulmonary hypertension caused by hyperthyroid heart disease.

Thyroid Dysfunction in Patients with Pulmonary Artery Hypertension (PAH): The Effect of Therapies Affecting the Prostanoid Pathway

INTRODUCTION

Epoprostenol, a synthetic prostaglandin I2 (PGI₂) analog, has been the mainstay of treatment for severe pulmonary arterial hypertension (PAH) for the last two decades. Treprostinil, another synthetic prostaglandin analog, and selexipag, an oral selective Inositol Phosphate (IP) prostacyclin receptor agonist, have also been approved for treatment of PAH. Prostacyclin and its analogs cause a variety of side effects in patients with PAH; however, thyroid dysfunction is rarely reported.

METHODS

After treating an index case of thyroid dysfunction occurring after initiation of epoprostenol, we reviewed our databases of PAH patients treated with epoprostenol, treprostinil or selexipag to identify the occurrence of this association.

RESULTS

We identified six cases of thyroid dysfunction in our cohort: five after initiation of an intravenous prostacyclin (epoprostenol) and one after initiation of an oral prostacyclin receptor agonist (selexipag). Four of the patients presented with hyperthyroidism and two with a large autoimmune goiter. Graves' disease was seen in three patients, Hashimoto's disease in two patients and thyrotoxicosis in one patient.

CONCLUSION

Therapy with medications targeting the prostacyclin pathway is a potential risk factor for the development of symptomatic thyroid disease.

Pattern and Presentation of Thyro-Cardiac Disease among Patients with Hyperthyroidism Attending a Tertiary Hospital in Ethiopia: A Cross Sectional Study

Background

Thyro-cardiac disease describes the existence of a combination of thyroid toxicity and significant heart disease in an individual patient. The frequent manifestations of thyro-cardiac disease are hypertension, atrial flutter or fibrillation, pulmonary hypertension and dilated cardiomyopathy. The aim of the study was to determine the pattern and presentation of cardiovascular diseases in patients with hyperthyroidism on follow-up at St. Paul's Hospital endocrine clinic.

Methods

It was a hospital based cross sectional study that evaluated hyperthyroid patients' on follow-up at St. Paul's Hospital for cardiovascular diseases from May 1^st 2017 to October 31^st 2017. They had focused history, physical examination, electrocardiographic and echocardiographic evaluation.

Results

A total of 146 hyperthyroid patients on follow-up were included in the study. The mean age was 47.2 years and females accounted for 93.2% of patients. The mean duration of symptoms before presentation was 42 months. The frequent causes of hyperthyroidism were toxic multi-nodular goitre (88.4%), Graves' disease (6.8%) and toxic adenoma (2.1%). Sixteen (11%) patients had atrial fibrillation and 71 (48.6%) had hypertension. Thyrocardiac disease was detected in 46.6% of patients. The frequent abnormalities were left ventricular hypertrophy (14.4%), mild diastolic dysfunction (10.9%), moderate to severe mitral regurgitation (8.9%), pulmonary hypertension with or without right ventricular dysfunction (8.2%) and dilated cardiomyopathy (4.1%).

Conclusion

Cardiovascular disease was frequent among patients with hyperthyroidism. The commonest abnormalities were systemic hypertension, pulmonary hypertension with or without isolated right sided heart failure, atrial fibrillation and dilated cardiomyopathy.

Hyperthyroidism with Biventricular Heart Failure and Cirrhotic Transformation of the Liver

Cardiovascular symptoms remain the most common presenting features and leading causes of death in hyperthyroidism. We report a young female with reported thyroid disease and medication noncompliance presenting with atrial fibrillation, severe atrioventricular regurgitation, severely dilated right heart with reduced function, and moderate pulmonary hypertension (PH), which was further complicated by congestive liver injury with ascites and pancytopenia. Thyroid work-up revealed suppressed TSH, elevated free T4 and T3 along with elevated anti-thyroglobulin antibodies, thyroid peroxidase antibodies, and thyroid-stimulating immunoglobulin, suggesting Graves' thyrotoxicosis. Ultrasound of the abdomen was suggestive of liver cirrhosis and ascites, which was thought to be cardiac cirrhosis, after multiple negative work-ups for alternate causes of cirrhosis. Ascitic fluid analysis revealed portal hypertension as the cause. The patient was restarted on antithyroid medication with gradual improvement of thyroid function and in clinical and echocardiogram findings. In contrast to primary PH that carries a poor prognosis and has limited treatment options, PH due to Graves' disease carries a good prognosis with prior reports of resolution after appropriate treatment, emphasizing the importance of early recognition. Also, unlike cirrhosis caused by alcohol or viral hepatitis, the effect of cardiac cirrhosis on overall prognosis has not been clearly established.

Prospective Echocardiographic Evaluation of the Right Ventricle and Pulmonary Arterial Pressure in Hyperthyroid Patients

BACKGROUND

Pulmonary arterial hypertension (PAH) occurs in 35% to 65% of hyperthyroid patients. Despite this high frequency, only a few authors have examined the effects of hyperthyroidism treatment on PAH and the right ventricle. We evaluated the effects of hyperthyroidism and its reversal on cardiovascular structure and function using Doppler echocardiography.

METHODS

We prospectively evaluated 32 patients (42.5±11.9years old) with thyrotoxicosis. Exclusion criteria included previous cardiovascular disease. An echocardiogram was performed at the time of hyperthyroidism diagnosis and after normalisation of free thyroxine (T4) levels. Patients were divided into two groups according to the presence or absence of PAH at the diagnosis, or at two moments, before and after T4 normalisation.

RESULTS

Graves' disease was the most frequent aetiology (75%) of hyperthyroidism. Pulmonary arterial hypertension was observed in 43.8% of patients. Free T4 concentration was higher in PAH than non-PAH patients. Free T4 normalised after 5 (2.0-10.5; median and percentiles) months of treatment. Cardiac chamber sizes and cardiac output were higher in PAH. Right ventricular (RV) systolic function was impaired in PAH. Cardiac output and free T4 (r=0.42; p<0.05) correlated with pulmonary artery systolic pressure (PASP). Cardiac chamber size, cardiac output, left ventricular ejection fraction, and PASP (34.0±8.6 to 21.7±4.5mmHg) reduced after treatment. Right ventricular myocardial performance index and fractional area change improved after T4 normalisation.

CONCLUSIONS

Pulmonary arterial hypertension is highly prevalent in hyperthyroid patients and is combined with increased cardiac chambers size and cardiac output, and impaired RV function. Cardiovascular changes are reversible after T4 normalisation in patients without cardiovascular disease.

Right ventricular dysfunction and pulmonary hypertension: a neglected presentation of thyrotoxicosis

Thyrotoxicosis is associated with cardiac dysfunction; more commonly, left ventricular dysfunction. However, in recent years, there have been more cases reported on right ventricular dysfunction, often associated with pulmonary hypertension in patients with thyrotoxicosis. Three cases of thyrotoxicosis associated with right ventricular dysfunction were presented. A total of 25 other cases of thyrotoxicosis associated with right ventricular dysfunction published from 1994 to 2017 were reviewed along with the present 3 cases. The mean age was 45 years. Most (82%) of the cases were newly diagnosed thyrotoxicosis. There was a preponderance of female gender (71%) and Graves' disease (86%) as the underlying aetiology. Common presenting features included dyspnoea, fatigue and ankle oedema. Atrial fibrillation was reported in 50% of the cases. The echocardiography for almost all cases revealed dilated right atrial and or ventricular chambers with elevated pulmonary artery pressure. The abnormal echocardiographic parameters were resolved in most cases after rendering the patients euthyroid. Right ventricular dysfunction and pulmonary hypertension are not well-recognized complications of thyrotoxicosis. They are life-threatening conditions that can be reversed with early recognition and treatment of thyrotoxicosis. Signs and symptoms of right ventricular dysfunction should be sought in all patients with newly diagnosed thyrotoxicosis, and prompt restoration of euthyroidism is warranted in affected patients before the development of overt right heart failure.

LEARNING POINTS

Thyrotoxicosis is associated with right ventricular dysfunction and pulmonary hypertension apart from left ventricular dysfunction described in typical thyrotoxic cardiomyopathy.Symptoms and signs of right ventricular dysfunction and pulmonary hypertension should be sought in all patients with newly diagnosed thyrotoxicosis.Thyrotoxicosis should be considered in all cases of right ventricular dysfunction or pulmonary hypertension not readily explained by other causes.Prompt restoration of euthyroidism is warranted in patients with thyrotoxicosis complicated by right ventricular dysfunction with or without pulmonary hypertension to allow timely resolution of the abnormal cardiac parameters before development of overt right heart failure.

Thyrotoxic Valvulopathy: Case Report and Review of the Literature

We report a 42-year-old female who was admitted for abdominal pain, and also endorsed dyspnea, fatigue and chronic palpitations. Past medical history included asthma, patent ductus arteriosus repaired in childhood and ill-defined thyroid disease. Physical examination revealed blood pressure of 136/88 mm Hg and heart rate of 149 beats per minute. Cardiovascular exam revealed an irregularly irregular rhythm, and pulmonary exam revealed mild expiratory wheezing. Abdomen was tender. Electrocardiogram revealed atrial fibrillation with rapid ventricular response which responded to intravenous diltiazem. Labs revealed TSH of < 0.1 mU/L and free T4 of 2.82 ng/dL, a positive TSH-receptor and thyroid peroxidase antibodies suggesting Grave’s thyrotoxicosis. A transthoracic echocardiogram reported an ejection fraction of 55-60%, with mild to moderate mitral regurgitation (MR) and moderate to severe tricuspid regurgitation (TR) and dilated right heart chambers. Pulmonary artery systolic pressure was 52 mm Hg. Transesophageal echocardiogram revealed a myxomatous tricuspid valve with thickening and malcoaptation of the leaflets and moderate to severe TR, mild to moderate MR with mild thickening of the mitral valve leaflets. Abdominal ultrasound revealed wall thickening of the gall bladder concerning for acute cholecystitis. She underwent laparoscopic cholecystectomy and was discharged in stable condition on methimazole for her thyroid disease, and on oral diltiazem for rate control and anticoagulation for atrial fibrillation. Follow-up visit with her cardiologist few months later documented absence of cardiac symptoms, and no murmurs were reported on physical examination. This case underscores the importance of maintaining a high index of suspicion for hyperthyroidism when faced with significant newly diagnosed pulmonary hypertension and TR, as treatment of the thyroid abnormalities can reverse these cardiac findings.

Thyrotoxicosis presenting as exertional dyspnea and pulmonary hypertension: Case report and review of literature

Objectives:

In this case study, we describe a 35-year-old woman with pulmonary hypertension that was secondary to thyrotoxicosis who presented with exertional dyspnea. In the approach to exertional dyspnea, detailed physical examination and laboratory findings helped to get the diagnosis.

Methods:

Echocardiography showed right ventricular systolic pressure = 60 mmHg. A suppressed thyroid-stimulating hormone was seen in lab tests. The patient was treated with radioactive iodine.

Results:

Palpitations and shortness of breath improved, and both her thyroid-stimulating hormone and T4 levels decreased. Echocardiography and the pulmonary pressure were normal after treatment.

Conclusions:

Thyrotoxicosis is one of the etiologies of pulmonary hypertension, but the exact etiology and pathogenesis remain unknown. Some patients may have symptomatic pulmonary hypertension that can be resolved by hyperthyroidism treatment.

Relationship Among Pulmonary Hypertension, Autoimmunity, Thyroid Hormones and Dyspnea in Patients With Hyperthyroidism

OBJECTIVE

Previous studies have reported conflicting results regarding the mechanisms underlying the pathophysiology of pulmonary hypertension (PHT) in patients with hyperthyroidism. Therefore, in this study, we investigated the association between PHT and thyroid-stimulating hormone (TSH) receptor antibody, thyroid peroxidase antibody, thyroglobulin antibody, TSH, fT3, fT4 and dyspnea during daily activities in a large population of patients with hyperthyroidism.

METHODS

A total of 129 consecutive patients with hyperthyroidism, 37 with hypothyroidism and 38 euthyroid controls were enrolled in this study. The modified medical research council scale was used for the assessment of dyspnea in daily activities. All the patients and euthyroid controls underwent transthoracic echocardiography for the assessment of PHT.

RESULTS

Mild PHT was present in 35%, 36%, 13.5% and 5% of the patients with Graves׳ disease, toxic multinodular goiter, hypothyroidism and euthyroid controls, respectively. Pulmonary vascular resistance (PVR) was higher in hyperthyroid patients with PHT than in those without PHT. Moreover, a significant positive correlation was found between modified medical research council scale and pulmonary artery systolic pressure as well as PVR in patients with hyperthyroidism. No association was found between PHT and serum TSH receptor antibody, thyroid peroxidase antibody, thyroglobulin antibody, TSH, fT3 and fT4 levels.

CONCLUSIONS

Mild PHT is present in a significant proportion of patients with hyperthyroidism, regardless of etiology. PVR appears to be the main cause of PHT in patients with hyperthyroidism, and neither autoimmunity nor thyroid hormones are associated with PHT in these patients. Mild dyspnea during daily activities in patients with hyperthyroidism may be related to PHT; however, severe dyspnea requires further evaluation.

Serum-Free Thyroxine Levels Were Associated with Pulmonary Hypertension and Pulmonary Artery Systolic Pressure in Euthyroid Patients with Coronary Artery Disease

The aim of this study was to evaluate the association between thyroid hormone levels, pulmonary hypertension (PH), and pulmonary artery systolic pressure (PASP) in euthyroid patients with coronary artery disease (CAD). A cross-sectional study was conducted in individuals who underwent coronary angiography and were diagnosed as CAD from March 2013 to November 2013. 811 subjects (185 women and 626 men) were included in this study. PASP was measured by transthoracic Doppler echocardiography. 86 patients were diagnosed as PH and had significantly higher free thyroxine (FT₄) levels than those without PH. Multiple logistic regression analysis demonstrated an independent association of FT₄ levels with PH after adjustment of gender, age, body mass index, systolic blood pressure, left ventricular ejection fraction, hypertension, and medication use of calcium channel blockers, ACE inhibitors, angiotensin II receptor antagonists, and nitrates. Serum-free triiodothyronine (FT₃) and thyroid-stimulating hormone (TSH) were not associated with PH. Furthermore, multivariate linear regression analysis showed that FT₄ levels emerged as an independent predictor for PASP, while FT₃ and TSH levels were not associated with PASP. Our study demonstrated that, in euthyroid patients with CAD, FT₄ was an independent risk factor for PH, and FT₄ levels were independently associated with PASP.

Pulmonary hypertension in thyroid diseases

The influence of thyroid hormones on cardiovascular system is well established. Thyroid diseases can effectively enhance the alteration on cardiovascular system by influencing chronotropic and inotropic actions of the heart; altering the strength and the speed of contraction, the speed of relaxation, the duration of the potential of action, and the duration of the refractory period and atrio-ventricular conduction time; modulating circulation and peripheral vascular beds. One of the more intriguing insights in the connection between thyroid diseases and cardiovascular alterations is related to the evaluation of the influence of thyroid hormones on pulmonary vascular beds. Literature reported several studies regarding the association between both hypothyroidism and hyperthyroidism and the occurrence of increased vascular pulmonary arterial pressure. Nevertheless, the pathogenetic mechanisms able to explain such relationship are not fully understood. Many doubts still persist in the comprehension of the mechanisms of pulmonary hypertension in thyroid diseases. The aim of this review was to provide possible explanation about the possible interaction between pulmonary vascular beds and thyroid function in order to evaluate the possibility of novel perspectives in the general management of patients suffering from thyroid and cardiovascular diseases.

Respiratory manifestations in endocrine diseases

The control mechanisms of respiration as a vital function are complex: voluntary - cortical, and involuntary - metabolic, neural, emotional and endocrine. Hormones and hypothalamic neuropeptides (that act as neurotrasmitters and neuromodulators in the central nervous system) play a role in the regulation of respiration and in bronchopulmonary morphology. This article presents respiratory manifestations in adult endocrine diseases that evolve with hormone deficit or hypersecretion. In hyperthyroidism, patients develop ventilation disorders, obstructive and central sleep apnea, and pleural collection. The respiratory abnormalities in hyperthyroidism as a result of the hypermetabolic action of thyroid hormones are hyperventilation, myopathy and cardiovascular involvement; recent studies have reported pulmonary arterial hypertension in Graves' disease, as a result of the association of several mechanisms. Thyroid hypertrophy can induce through compression of the upper airways dyspnea, stridor, wheezing and cough. The respiratory disorders in acromegaly are ventilatory dysfunction and sleep apnea, which contribute to an unfavorable evolution of the disease. Respiratory changes in parathyroid, adrenal and reproductive system diseases have been described. Respiratory disorders should be recognized, investigated and monitored by medical practitioners of various specialties (family physicians, internists, endocrinologists, pneumologists, cardiologists). They are frequently severe, causing an unfavorable evolution of the associated endocrine and respiratory disease.

Clinical Presentation, Differential Diagnosis, and Vasodilator Testing of Pulmonary Hypertension

Clinicians should be cognizant of the symptoms and risk factors associated with pulmonary hypertension (PH). While known PH poses significant therapeutic challenges, occult PH carries the added potential for unanticipated complications when treating concurrent medical illnesses. PH may occur with underlying medical conditions and risk factors or may occur de novo as idiopathic pulmonary arterial hypertension (IPAH). Symptoms of PH are frequently attributed to more common conditions, and their nonspecific nature and insidious onset may lead to delay in presentation, evaluation, and diagnosis. Initial symptoms are dyspnea, fatigue, chest pain, and palpitations. Lower extremity edema, presyncope, and syncope are symptoms of more advanced disease. Thorough evaluation of symptoms and identification of patients with risk factors for PH are critical in making a timely diagnosis. History and physical examination can identify patients with suspected PH. Further testing is necessary for definitive diagnosis, classification, assessment of severity, and guiding therapeutic decisions.

Thyroid disease and the cardiovascular system

Thyroid hormones, specifically triiodothyronine (T3), have significant effects on the heart and cardiovascular system. Hypothyroidism, hyperthyroidism, subclinical thyroid disease, and low T3 syndrome each cause cardiac and cardiovascular abnormalities through both genomic and nongenomic effects on cardiac myocytes and vascular smooth muscle cells. In compromised health, such as occurs in heart disease, alterations in thyroid hormone metabolism may further impair cardiac and cardiovascular function. Diagnosis and treatment of cardiac disease may benefit from including analysis of thyroid hormone status, including serum total T3 levels.

Unexpected causes of pulmonary hypertension in a previously healthy Thai rural man with right-sided heart failure

Male, 52

Final Diagnosis: Pulmonary hypertension

Symptoms: Diarrhea • dyspnea • jaundice

Medication: —

Clinical Procedure: —

Specialty: Endocrinology and Metabolic

Thyroid hormone levels in apparently euthyroid subjects with essential hypertension in a tertiary hospital in Nigeria

Background:

High blood pressure (BP) is a major health problem in Nigeria and the involvement of thyroid hormones in this condition has not been evaluated in this center.

Objective:

The objective of this study was to evaluate the proportion of patients with an essential hypertension who had abnormal thyroid hormone levels and the type of thyroid disorders commonly observed in this group of patients.

Materials and Methods:

A retrospective study of 94 patients (30 males, aged 30.4 ± 2 years and 64 females, aged 43.4 ± 1.3 years) with essential hypertension was carried out between January 2005 and December 2007. Demographic and other medical information were obtained from the health records. Analysis of laboratory results of triiodothyronine (T₃), Thyroxine (T₄), and thyroid stimulating hormone (TSH) were made.

Results:

Of the 94 patients evaluated, 26 (27.7%) had abnormal thyroid hormone levels, with 23.4% having hyperthyroidism, 4.3% had sub-clinical hypothyroidism and none had overt hypothyroidism. Of the 26 subjects with abnormal thyroid hormone levels, 18 (69.2%) were females while 8 (30.8%) were males. Out of the 18 female subjects with abnormal thyroid hormone levels, 16 had hyperthyroid levels while 2 had sub-clinical hypothyroid levels. Out of the 8 male patients, 6 had hyperthyroid hormone levels while 2 had sub-clinical hypothyroid levels.

Conclusion:

Thyroid hormone abnormalities are common in patients with essential hypertension. Hyperthyroidism was the most common thyroid disorder observed. Young patients presenting with essential hypertension should be screened for thyroid hormone abnormalities since they can best be managed by treating the underlying causes.

Mechanisms in endocrinology: Heart failure and thyroid dysfunction

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. The investigation was restricted to reports published in English.

EVIDENCE SYNTHESIS

The outcome of this analysis suggests that patients with untreated overt thyroid dysfunction are at increased risk of HF. Moreover, persistent subclinical thyroid dysfunction is associated with the development of HF in patients with serum TSH <0.1 or > 10 mU/l.

CONCLUSIONS

The timely recognition and effective treatment of cardiac symptoms in patients with thyroid dysfunction is mandatory because the prognosis of HF may be improved with the appropriate treatment of thyroid dysfunction.

Pediatric pulmonary arterial hypertension and hyperthyroidism: a potentially fatal combination

CONTEXT

Patients with pulmonary arterial hypertension (PAH) who develop hyperthyroidism are at risk for acute cardiopulmonary decompensation and death.

CASES AND SETTING

We present a series of eight idiopathic PAH/heritable PAH pediatric patients who developed hyperthyroidism between 1999 and 2011. Institutional Review Board approval was obtained; informed consent was waived due to the retrospective nature of the series. All eight patients were receiving iv epoprostenol; five of the eight patients presented with acute cardiopulmonary decompensation in the setting of hyperthyroidism. In the remaining three patients, hyperthyroidism was detected during routine screening of thyroid function tests. The one patient who underwent emergency thyroidectomy was the only survivor of those who presented in cardiopulmonary decline.

EVIDENCE SYNTHESIS

Aggressive treatment of the hyperthyroid state, including emergency total thyroidectomy and escalation of targeted PAH therapy and β-blockade when warranted, may prove lifesaving in these patients. Prompt thyroidectomy or radioactive iodine ablation should be considered for clinically stable PAH patients with early and/or mild hyperthyroidism to avoid potentially life-threatening cardiopulmonary decompensation.

CONCLUSIONS

Although the association between hyperthyroidism and PAH remains poorly understood, the potential impact of hyperthyroidism on the cardiopulmonary status of PAH patients must not be ignored. Hyperthyroidism must be identified early in this patient population to optimize intervention before acute decompensation. Thyroid function tests should be checked routinely in patients with PAH, particularly those on iv epoprostenol, and urgently in patients with acute decompensation or symptoms of hyperthyroidism.

Pulmonary complications of endocrine and metabolic disorders

There are many important respiratory manifestations of endocrine and metabolic diseases in children. Acute and chronic pulmonary infections are the most common respiratory abnormalities in patients with diabetes mellitus, although cardiogenic and non-cardiogenic pulmonary oedema are also possible. Pseudohypoaldosteronism type 1 may be indistinguishable from cystic fibrosis (CF) unless serum aldosterone, plasma renin activity, and urinary electrolytes are measured and mutation analysis rules out CF. Hypo- and hyperthyroidism may alter lung function and affect the central respiratory drive. The thyroid hormone plays an essential role in lung development, surfactant synthesis, and lung defence. Complications of hypoparathyroidism are largely due to hypocalcaemia. Laryngospasm can lead to stridor and airway obstruction. Ovarian tumours, benign or malignant, may present with unilateral or bilateral pleural effusions. Metabolic storage disorders, primarily as a consequence of lysosomal dysfunction from enzymatic deficiencies, constitute a diverse group of rare conditions that can have profound effects on the respiratory system.

Hyperthyroidism and pulmonary hypertension: an important association

Pulmonary hypertension is a complex disorder with multiple etiologies. The World Health Organization Group 5 (unclear multifactorial mechanisms) includes patients with thyroid disorders. The authors reviewed the literature on the association between hyperthyroidism and pulmonary hypertension and identified 20 publications reporting 164 patients with treatment outcomes. The systolic pulmonary artery (PA) pressures in these patients ranged from 28 to 78 mm Hg. They were treated with antithyroid medications, radioactive iodine and surgery. The mean pretherapy PA systolic pressure was 39 mm Hg; the mean posttreatment pressure was 30 mm Hg. Pulmonary hypertension should be considered in hyperthyroid patients with dyspnea. All patients with pulmonary hypertension should be screened for hyperthyroidism, because the treatment of hyperthyroidism can reduce PA pressures, potentially avoid the side-effects and costs with current therapies for pulmonary hypertension and limit the consequences of untreated hyperthyroidism. However, the long-term outcome in these patients is uncertain, and this issue needs more study. Changes in the pulmonary circulation and molecular regulators of vascular remodeling likely explain this association.

A case of pulmonary arterial hypertension associated with hyperthyroidism, persistent after euthyroidism was obtained

Cardiovascular manifestations in hyperthyroidism occur frequently with various phenotypes. An association between hyperthyroidism and pulmonary arterial hypertension has been reported. In previously reported cases, the hemodynamic and symptomatic recovery of pulmonary arterial hypertension is usually concomitant with achievement of euthyroidism. We report a patient who had pulmonary arterial hypertension associated with Graves' disease, which persisted after euthyroidism was obtained.

Cardiovascular involvement in patients with different causes of hyperthyroidism

Various clinical disorders can cause hyperthyroidism, the effects of which vary according to the patient's age, severity of clinical presentation and association with other comorbidities. Hyperthyroidism is associated with increased morbidity and mortality from cardiovascular disease, although whether the risk of specific cardiovascular complications is related to the etiology of hyperthyroidism is unknown. This article will focus on patients with Graves disease, toxic adenoma and toxic multinodular goiter, and will compare the cardiovascular risks associated with these diseases. Patients with toxic multinodular goiter have a higher cardiovascular risk than do patients with Graves disease, although cardiovascular complications in both groups are differentially influenced by the patient's age and the cause of hyperthyroidism. Atrial fibrillation, atrial enlargement and congestive heart failure are important cardiac complications of hyperthyroidism and are prevalent in patients aged > or = 60 years with toxic multinodular goiter, particularly in those with underlying cardiac disease. An increased risk of stroke is common in patients > 65 years of age with atrial fibrillation. Graves disease is linked with autoimmune complications, such as cardiac valve involvement, pulmonary arterial hypertension and specific cardiomyopathy. Consequently, the etiology of hyperthyroidism must be established to enable correct treatment of the disease and the cardiovascular complications.

J, Hajdú J. Severe circulatory insufficiency in a patient with neonatal hyperthyroidism

A szerzők egy Basedow–Graves-kór miatt korábban thyreoidectomián átesett, kezeletlen anya koraszülöttjének esetét ismertetik. Gondozatlan terhességből magzati tachycardia, fenyegető intrauterin asphyxia miatt sürgős császármetszéssel született a 33. hétnek megfelelő érettségű, 1350 gramm súlyú, dysmaturus (testsúlypercentil <10), nagy nyaki strumával bíró koraszülött. Az újszülött respiratoricus elégtelenség miatt konvencionális és magas frekvenciás gépi lélegeztetésben részesült, súlyos tachycardia (>180/perc), cardialis decompensatio miatt béta-blokkoló, digoxin- és dobutaminterápiát igényelt. Kivizsgálása során cardiomegalia, pericardialis folyadékgyülem, súlyos tüdőhypoplasia, mitralis és tricuspidalis insufficientia, hepatosplenomegalia igazolódott. A pajzsmirigy-szabadhormonok szintje többszörösen meghaladta a referenciaértéket (fT4: > 6 ng/dl, fT3: > 30 pg/ml), a TSH-szint ugyanakkor 0 volt. Légzéstámogatást 7, keringéstámogatást 10 napig igényelt, propranolol- mellett K-jodid-kezelésben részesült. Tachycardiája mérséklődött, a béta-blokkoló kezelést csökkentett adagban kapta tovább, pajzsmirigyhormonszintjei fokozatosan a normális tartományba kerültek. A szerzők felhívják a figyelmet arra, hogy a Basedow–Graves-kórban szenvedő anya újszülöttjénél jelentős súlybeli, növekedésbeli elmaradás, súlyos keringési elégtelenség, thyreotoxicosis tünetei alakulhatnak ki, és hangsúlyozzák az anyai hormon-, valamint antitestszintek nyomon követésének jelentőségét.

Pulmonary arterial hypertension and thyroid disease

Recent studies have suggested an association between pulmonary arterial hypertension (PAH) and thyroid diseases (hypothyroidism and hyperthyroidism). This combination has a good prognosis, because the increase in the pulmonary artery pressure is usually slight and reverses after the treatment of the thyroid disease. Although the exact mechanism involved in the pathogenesis of this combination has not yet been established, it has been hypothesized that thyroid hormones and autoimmunity have a direct influence. Due to the high prevalence of thyroid disease in patients with PAH, thyroid function tests should be considered in the investigation of every patient with PAH. In this review, we describe the prevalence of PAH in patients with thyroid diseases and the prevalence of thyroid disease in patients with PAH, as well as addressing the principal effects that thyroid diseases have on the respiratory system. In addition, we report the treatment effects in patients with these diseases.

QTc dispersion in hyperthyroidism and its association with pulmonary hypertension

BACKGROUND

Several studies have reported that hyperthyroidism is associated with prolonged QT interval corrected by the heart rate (QTc) and pulmonary hypertension (PHT).

METHODS

Forty-seven patients with newly diagnosed overt hyperthyroidism and 20 healthy people were enrolled in the study. Transthoracic echocardiography, 12-lead surface electrocardiogram, and thyroid hormone levels were studied at the time of enrollment and after achievement of euthyroid state with propylthiouracil treatment.

RESULTS

Baseline clinical characteristics were similar. However, heart rate (90.5+/-19.6 vs 79.2+/-13.7 bpm, P = 0.024), pulmonary artery systolic pressure (PASP) (26.0+/-12.0 vs 10.6+/-4.0 mmHg, P < 0.001), E deceleration time (DT) (191.8+/-25.6 vs 177.0+/-10.7 ms, P = 0.016), isovolumetric relaxation time (IVRT) (91.38+/-12.3 vs 79.6+/-10.5 ms, P < 0.001), and QTc dispersion (QTcD) (50.3+/-17.2 vs 38.9+/-11.6 ms, P = 0.009) were significantly higher in hyperthyroid patients compared to control group. Heart rate (to 74.1+/-13.8, P < 0.001), QTcD (to 37.3+/-10.1 ms, P < 0.001), DT (to 185.3+/-19.7 ms, P = 0.008), IVRT (to 88.6+/-10.3 ms, P = 0.056), and PASP (23.1+/-10.1 mmHg P < 0.001) were significantly decreased after achievement of euthyroid state. Although PHT was present in 16 patients before treatment only six patients still had PHT during euyhyroid state. Compared to patients with normal PASP, QTcD was significantly longer in patients with PHT (56.5+/-15.8 vs 37.9+/-12.8 mmHg P < 0.001). There were also significant correlations between QTcD and presence of PHT (r = 0.516, P < 0.001) and PASP (r = 0.401, P = 0.009).

CONCLUSIONS

Hyperthyroidism is a reversible cause of PHT and diastolic dysfunction. Increased QTcD observed in hyperthyroidism may be associated with PHT and diastolic dysfunction. These abnormal findings in hyperthyroidism often normalize with the achievement of euthyroid state.

Pulmonary hypertension responding to hyperthyroidism treatment

Pulmonary hypertension in adults with hyperthyroidism is increasingly being reported. Although the mechanism is uncertain, the reversal of pulmonary hypertension following restoration to an euthyroid state supports a causal relationship. This case report is of a 43-year-old woman who presented with Graves disease and right ventricular failure. Echocardiography showed severe pulmonary hypertension, moderate to severe tricuspid regurgitation, normal left heart function and a negative bubble contrast study. Carbimazole therapy was instituted along with diuretics and captopril. The patient was followed for a period of 14 months. Clinical and biochemical euthyroidism was attained after 4 months of treatment. Resolution of right ventricular failure and normalization of pulmonary artery pressure occurred 11 and 14 months after initiation of therapy, respectively. Investigating thyroid status in patients with pulmonary hypertension is recommended. In patients with hyperthyroidism and (otherwise unexplained) pulmonary hypertension, restoration of euthyroidism may cure right ventricular failure and restore normal pulmonary artery pressure.

Pulmonary Hypertension and Thyroid Disease

BACKGROUND

The association between thyroid dysfunction and pulmonary hypertension (PH) has not been well characterized.

METHODS

This retrospective study comprised 356 consecutive PH patients seen at Mayo Clinic Jacksonville Pulmonary Hypertension Center from 1992 to 2006 and 698 sex-matched control subjects without PH. Thyroid disease was defined as an abnormal thyroid-stimulating hormone level, with or without an abnormal free or total thyroxine level, a history of thyroid disease on replacement, or an elevated thyroperoxidase antibody level. The main outcome measure was prevalence of thyroid disease in each group.

RESULTS

Median age of the 356 PH patients was 65 years; 230 patients (65%) were female. The control group of 698 patients had the same sex ratio and median age of 68 years. Most PH patients had severe PH, as categorized by World Health Organization (WHO) class (74% class 3-4) and pulmonary artery systolic pressure. Among those with PH, 85 patients (24%) had thyroid disease vs 107 control patients (15%). After adjusting for age and sex, the prevalence of thyroid disease was increased in PH patients compared with control patients. Increased prevalence was most prominent in WHO group 1, pulmonary artery hypertension confirmed by right-heart catheterization (odds ratio, 2.53; 95% confidence interval, 1.55 to 4.08; p < 0.001). Most patients had mild thyroid disease and were hypothyroid. Only 14 of 85 patients (16%) had previously undiagnosed thyroid disease.

CONCLUSIONS

Patients with PH have a higher prevalence of thyroid disease than other pulmonary patients. Evaluation of thyroid function in PH patients may be warranted to detect and assess coexisting thyroid disease.

Reversible pulmonary hypertension and isolated right-sided heart failure associated with hyperthyroidism

Hyperthyroidism may present with signs and symptoms related to dysfunction of a variety of organs. Cardiovascular pathology in hyperthyroidism is common. A few case reports describe isolated right heart failure, tricuspid regurgitation, and pulmonary hypertension as the prominent cardiovascular manifestations of hyperthyroidism. Although most textbooks do not mention hyperthyroidism as a cause of pulmonary hypertension and isolated right heart failure, the literature suggests that some hyperthyroid patients may develop reversible pulmonary hypertension and isolated right heart failure. We report a case of hyperthyroidism presenting with signs and symptoms of isolated right heart failure, tricuspid regurgitation, and pulmonary hypertension, which resolved with treatment of hyperthyroidism.

Hyperthyroidism as a cause of pulmonary arterial hypertension: a prospective study

The authors assessed the prevalence of pulmonary arterial hypertension (PAH) in patients with hyperthyroidism and evaluated the response to treatment of the thyrotoxicosis. They assessed the pulmonary artery systolic pressure (PASP) at rest (estimated by echocardiography) in 23 consecutive patients diagnosed with hyperthyroidism due to Graves' disease or toxic multinodular goiter. Twelve of 23 patients (52%) did not show antithyroglobulin and antithyroperoxidase antibodies. Seventeen patients were followed up for at least 9 months after achieving a stable euthyroid status. Fifteen (65%) patients demonstrated PAH at admission. Four patients were lost to follow-up; therefore they were able to evaluate 17 patients serially with echocardiography. Sixteen patients normalized their PASP value: 13 after methimazole, 2 after total thyroidectomy, and 1 after (131)I treatment. In 1 patient no significant change in PASP was observed. This patient experienced an acute myocardial reinfarction during follow-up. They found a higher prevalence than that previously reported in observational studies. In addition, they demonstrated that the PAH reverses after correction of hyperthyroidism. Elevated PASP at rest on echocardiography may be considered a frequent finding of thyrotoxicosis. Moreover, the data seem not to support an autoimmune pathogenesis for PAH.

Hyperthyroidism: A Secondary Cause of Isolated Systolic Hypertension

Isolated systolic hypertension is the most common form of hypertension, especially among patients 50 years or older. What is not appreciated is that there are secondary causes of isolated systolic hypertension. Hyperthyroidism increases systolic blood pressure by decreasing systemic vascular resistance, increasing heart rate, and raising cardiac output. Potential cardiovascular consequences of hyperthyroidism include atrial arrhythmias (especially atrial fibrillation), pulmonary hypertension, left ventricular hypertrophy, and heart failure. The prevalence of hypertension is greater among hyperthyroid patients than euthyroid patients. Whether there is a blunted nocturnal decline in ambulatory blood pressure among hyperthyroid patients is more controversial. Treatment is associated with a reduction in systolic blood pressure, heart rate, and cardiac output.

Pulmonary hypertension is frequent in hyperthyroidism and normalizes after therapy

BACKGROUND

In recent years, many authors have described several cases revealing an association between hyperthyroidism and pulmonary hypertension. This observational study was designed to evaluate the prevalence of pulmonary hypertension in hyperthyroidism and to determine the role of methimazole in regulating pulmonary vascular resistance in these patients.

METHODS

We studied 114 patients, 78 women and 36 men, whose mean age was 51+/-13years. Forty-seven had Graves' disease and 67 had a nodular goiter. All subjects were ambulatory and were recruited in a consecutive order. The control group (group 2) included 20 healthy subjects matched for age and sex. Transthoracic Doppler echocardiography was performed and systolic pulmonary artery pressure (PAPs) was determined by the tricuspid regurgitation method using the Bernoulli's equation. We performed a 120-day follow-up in the patients with pulmonary hypertension and we divided them into two subgroups: group 1A (n=33), patients treated with methimazole, and group 1B (n=17), subjects treated with partial thyroidectomy.

RESULTS

We found a mild pulmonary hypertension in 50 patients in group 1 (43%) and in none of those in the control group. The mean+/-SD PAPs was 27.77+/-6.56 in group 1 and 21.32+/-2.55 in group 2. A negative correlation was found between the T.S.H. value and the level of PAPs (r=-0.85; p<0.001). During the follow-up, group 1A went from a PAPs value of 34.3+/-3.2 to 29.2+/-3.3 after 15days of therapy and group 1B from 34.3+/-3.0 to 34.1+/-2.9 (p<0.001).

CONCLUSIONS

The results of the present study demonstrate a frequent association between hyperthyroidism and mild and transient pulmonary hypertension. Subjects treated with methimazole have a more rapid drop in PAPs.

Pregnancy complicated with pulmonary edema due to hyperthyroidism

Hyperthyroidism is one of the most common causes of cardiac failure. Blood volume expands greatly during pregnancy, especially after the last part of the second trimester. Such expansion exacerbates the symptoms of heart failure and accelerates the development of pulmonary edema when abnormal thyroid function is not well controlled. Two cases of pregnancy complicated with congestive heart failure and pulmonary edema due to hyperthyroidism are reported here. Both patients did not receive treatment for hyperthyroidism during pregnancy, and both sought clinical help during the third trimester. The clinical problems were resolved by medical management before delivery.

Pulmonary hypertension in men with thyrotoxicosis

Thyrotoxicosis has a myriad of respiratory symptoms including dyspnea. Pulmonary hypertension may contribute to the respiratory symptoms of thyrotoxicosis, but is often unrecognized. We describe 3 male patients with thyrotoxicosis and associated pulmonary hypertension. Case reports of an additional 15 patients are also reviewed. In patients with thyrotoxicosis and pulmonary hypertension, treatment of thyrotoxicosis alone is associated with improvement in pulmonary hypertension. Previous reports have consisted of mostly female patients, but we report 3 men. When all cases are considered, the typical patient is female (10/14 = 71%), middle-aged (48 years), with mean pulmonary artery systolic pressures improving from 56 to 32 mm Hg with treatment. Autoantibodies were detected in 10/14 (71%) patients. The response to treatment (medical or surgical) of thyrotoxicosis supports the hypothesis that hyperthyroidism is either a cause of pulmonary hypertension, or a factor that may unmask pulmonary hypertension. Recognition is important since treatment and response are very different compared to other patients with pulmonary hypertension. This association may not be readily considered in men, since most reports have been of women.

Reversible pulmonary hypertension, tricuspid regurgitation and right-sided heart failure associated with hyperthyroidism: case report and review of the literature

Primary pulmonary hypertension carries a grim prognosis, therefore, it is imperative that prior to reaching this diagnosis, a thorough search be made for all possible causes of pulmonary hypertension. An uncommon cause of pulmonary hypertension amenable to treatment may occasionally be identified. This case report describes a young woman who presented with rapidly progressive right heart failure. Work up for the common secondary causes of pulmonary hypertension was negative, including, congenital intracardiac shunts, left-sided atrial or ventricular heart disease, left-sided valvular heart disease, disorders of the respiratory system including hypoxemia and pulmonary thromboembolic and venoocclusive disease, collagen vascular disease, portal hypertension, HIV infection as well as pulmonary hypertension secondary to drugs and toxins. The only concurrent illness identified was Graves disease. After treatment of hyperthyroidism there was complete resolution of the right heart failure, tricuspid regurgitation, and the pulmonary hypertension. Only a few cases of reversible pulmonary hypertension and right heart failure associated with hyperthyroidism have been reported worldwide. In these patients, the most striking feature has been the normalization of the cardiovascular findings after adequate treatment of hyperthyroidism. The exact reasons for the development of pulmonary hypertension in hyperthyroidism are unclear. Proposed mechanisms include high cardiac output-induced endothelial injury, increased metabolism of intrinsic pulmonary vasodilating substances resulting in elevated pulmonary vascular resistance, and autoimmune phenomenon. Hyperthyroidism should be included in the causes of secondary pulmonary hypertension and/or otherwise unexplained right heart failure. This is especially important because hyperthyroidism is a treatable entity and its cardiac manifestations may be completely reversible.

Neonatal thyrotoxicosis and persistent pulmonary hypertension necessitating extracorporeal life support

We report a case of neonatal Graves' disease involving an infant with severe persistent pulmonary hypertension (PPHN) associated with neonatal thyrotoxicosis that necessitated extracorporeal membrane oxygenation. Hyperthyroidism, although uncommon in the newborn period, has been associated with pulmonary hypertension among adults. The exact mechanisms responsible for this effect on pulmonary vascular pressure are not well understood. Recent studies have provided evidence that thyrotoxicosis has direct and indirect effects on pulmonary vascular maturation, metabolism of endogenous pulmonary vasodilators, oxygen economy, vascular smooth muscle reactivity, and surfactant production, all of which may contribute to the pathophysiologic development of PPHN. Therefore, because PPHN is a significant clinical entity among term newborns and the symptoms of hyperthyroidism may be confused initially with those of other underlying disorders associated with PPHN (eg, sepsis), it would be prudent to perform screening for hyperthyroidism among affected newborns.

Thyroid hormone and blood pressure regulation

Thyroid hormone has well-recognized effects on the cardiovascular system and blood pressure regulation. Blood pressure is altered across the entire spectrum of thyroid disease. The effects of hyperthyroidism include increased cardiac output, contractility, tachycardia, widened pulse pressure, decreased systemic vascular resistance, and increased basal metabolic rate. The manifestations of hypothyroidism are in marked contrast to those of hyperthyroidism and include decreased cardiac output, narrow pulse pressure, increased systemic vascular resistance, and decreased metabolic rate. Although thyroid hormone affects almost all tissues of the body and mediates changes in homeostasis, adaptations of the cardiovascular system can result in changes in blood pressure to accommodate the new demands on the system. In this paper, we review the direct and indirect thyroid hormone-mediated effects on blood pressure.