Epidemiology, prognosis, and challenges in the management of hyperthyroidism-related atrial fibrillation.

Atrial fibrillation (AF) is a common condition with a global estimated prevalence of 60 million cases, and the most common cardiac complication of hyperthyroidism, occurring in 5-15% of overtly hyperthyroid patients. Additionally, subclinical hyperthyroidism and high-normal free T4 have been associated with an increased risk in the development of AF. Hyperthyroidism-related AF is a reversible cause of AF, and the majority of patients spontaneously revert to sinus rhythm in 4-6 months during or after restoration of euthyroidism. Therefore, restoring thyroid function is an indispensable element in hyperthyroidism-related AF management. Rate control with beta-blockers consists another first-line therapy, reserving rhythm control in cases of persistent hyperthyroidism-related AF. It is still controversial whether hyperthyroidism is an independent risk factor of stroke in nonvalvular AF. As a result, initiating anticoagulation should be guided by the clinical thromboembolic risk score CHA2DS2-VASc score in the same way it is applied in patients with non-hyperthyroidism-related AF. Treatment with the novel direct oral anticoagulants appears to be as beneficial and may be safer than warfarin in patients with hyperthyroidism-related AF. In this review, we address the epidemiology, prognosis, and diagnosis of hyperthyroidism-related AF, and we discuss the management strategies and controversies in patients with hyperthyroidism-related AF.

Development and Validation of a Prediction Model for Incident Hypothyroidism in a National Chronic Kidney Disease Cohort.

CONTEXT: Hypothyroidism is a common yet under-recognized condition in patients with chronic kidney disease (CKD), which may lead to end-organ complications if left untreated. OBJECTIVE: We developed a prediction tool to identify CKD patients at risk for incident hypothyroidism. METHODS: Among 15 642 patients with stages 4 to 5 CKD without evidence of pre-existing thyroid disease, we developed and validated a risk prediction tool for the development of incident hypothyroidism (defined as thyrotropin [TSH] > 5.0 mIU/L) using the Optum Labs Data Warehouse, which contains de-identified administrative claims, including medical and pharmacy claims and enrollment records for commercial and Medicare Advantage enrollees as well as electronic health record data. Patients were divided into a two-thirds development set and a one-third validation set. Prediction models were developed using Cox models to estimate probability of incident hypothyroidism. RESULTS: There were 1650 (11%) cases of incident hypothyroidism during a median follow-up of 3.4 years. Characteristics associated with hypothyroidism included older age, White race, higher body mass index, low serum albumin, higher baseline TSH, hypertension, congestive heart failure, exposure to iodinated contrast via angiogram or computed tomography scan, and amiodarone use. Model discrimination was good with similar C-statistics in the development and validation datasets: 0.77 (95% CI 0.75-0.78) and 0.76 (95% CI 0.74-0.78), respectively. Model goodness-of-fit tests showed adequate fit in the overall cohort (P = .47) as well as in a subcohort of patients with stage 5 CKD (P = .33). CONCLUSION: In a national cohort of CKD patients, we developed a clinical prediction tool identifying those at risk for incident hypothyroidism to inform prioritized screening, monitoring, and treatment in this population.

Association Between Subclinical Thyroid Dysfunction and Fracture Risk.

Importance: Clinical hyperthyroidism accelerates bone resorption without compensatory bone formation, reducing bone density and increasing the risk of fracture. The association between subclinical hyperthyroidism and fracture risk is less clear. Objective: To investigate the association of endogenous subclinical thyroid dysfunction and fracture risk, independent of clinical confounders. Design, Setting, and Participants: This cohort study included 10 946 participants from the Atherosclerosis Risk in Communities Study, an ongoing prospective cohort study of community-dwelling individuals conducted from 1987-1989 through December 31, 2019, in Washington County, Maryland; Forsyth County, North Carolina; Jackson, Mississippi; and the suburbs of Minneapolis, Minnesota. Participants were not taking thyroid medications and had no history of fractures. Exposures: Thyrotropin and free thyroxine levels were measured at visit 2 (1990-1992). Subclinical hyperthyroidism was defined as a thyrotropin level lower than 0.56 mIU/L, subclinical hypothyroidism as a thyrotropin level higher than 5.1 mIU/L, and euthyroidism as a thyrotropin level of 0.56 to 5.1 mIU/L, with normal free thyroxine levels from 0.85 to 1.4 ng/dL. Main Outcomes and Measures: Incident fracture was ascertained using hospitalization discharge codes through 2019 and linkage to inpatient and outpatient Medicare claims through 2018. Results: Of 10 946 participants (54.3% women; mean [SD] age, 57 [5.7] years), 93.0% had euthyroidism, 2.6% had subclinical hyperthyroidism, and 4.4% had subclinical hypothyroidism. During a median follow-up of 21 years (IQR, 13.0-27.3 years), there were 3556 incident fractures (167.1 per 10 000 person-years). The adjusted hazard ratios of fracture were 1.34 (95% CI, 1.09-1.65) for those with subclinical hyperthyroidism and 0.90 (95% CI, 0.77-1.05) for those with subclinical hypothyroidism compared with individuals with euthyroidism. Among those with normal free thyroxine levels, thyrotropin levels in the lower-than-normal range were significantly associated with higher fracture-related hospitalization risk; fracture risk was greater among individuals with thyrotropin concentrations below 0.56 mIU/L. Conclusions and Relevance: This community-based cohort study suggests that subclinical hyperthyroidism was an independent risk factor associated with fracture. The increased risk for fracture among individuals with a thyrotropin level lower than 0.56 mIU/L highlights a potential role for more aggressive screening and monitoring of patients with subclinical hyperthyroidism to prevent bone mineral disease.

[Clinical-epidemiological profile of patients with thyrotoxic periodic paralysis in two peruvian hospitals]. / Perfil clínico-epidemiológico de pacientes con parálisis periódica tirotóxica en dos hospitales peruanos.

Background: Thyrotoxic Periodic Paralysis (PPT) is an uncommon complication of hyperthyroidism, it is the most frequent cause of acute flaccid paralysis in adults. Material and methods: A retrospective observational study was carried out in 2 reference hospitals of the social security in Lima-Peru, which included 22 patients diagnosed with PPT during the period 2014-2021. Results: the average age at diagnosis was 35.77 ± 9.6 years, all of mixed race, in 82% of the patients the diagnosis of hyperthyroidism was established from this entity, the etiology in 95% was autoimmune (Graves-Basedow) except for one whose etiology was toxic multinodular goiter. The triggering event reported in 54% of patients was the intake of copious food high in carbohydrates, followed by exercise (27%), the most frequent presentation time was during the morning (41% of the cases), the main weakness pattern compromised lower limbs (45% paraplegia, 18% paraparesis), only 36% were diagnosed with PPT in their first episode of motor weakness. Conclusions: We consider that this condition should be suspected in any young male patient of any ethnicity with acute muscle weakness, associated with low serum potassium levels and symptoms of thyrotoxicosis, although its absence should not rule out the diagnosis. The precipitating factor should be identified as much as possible and initial therapy with propanolol with or without intravenous or oral potassium replacement should be established, with adequate subsequent monitoring to minimize the risk of rebound hyperkalemia.

Introducción: la paralisis periodica tirotóxica (PPT) es una complicación poco común del hipertiroidismo, corresponde la causa más frecuente de parálisis aguda flácida del adulto. Material y métodos: se realizó un estudio observacional retrospectivo en 2 hospitales referenciales del seguro social en Lima-Perú, que incluyo a 22 pacientes (21 hombres, 1 mujer) diagnosticados con PPT durante el periodo 2014-2021. Resultados: la edad promedio al diagnóstico fue de 35.77 ± 9.6 años, todos de raza mestiza, en 82% de los pacientes el diagnostico de hipertiroidismo fue establecido a partir de esta entidad, la etiología en el 95% fue autoinmune (enfermedad de Graves-Basedow) excepto uno cuya etiología fue bocio multinodular tóxico. El evento desencadenante reportado en 54% de pacientes fue la ingesta de comida copiosa alta en carbohidratos, seguido del ejercicio (27%), el horario más frecuente de presentación fue durante la mañana ( 41% de los casos), el patrón de debilidad principal comprometió miembros inferiores(45% paraplejia, 18% paraparesia), solo 36% fue diagnosticado de PPT en su primer episodio de debilidad motora. Conclusiones: consideramos que se debe sospechar esta condición en cualquier paciente varón joven de cualquier etnia con debilidad muscular aguda, asociado a niveles séricos bajos de potasio y síntomas de tirotoxicosis, aunque su ausencia no debe descartar el diagnostico. Se debe identificar en lo posible el factor precipitante e instaurar terapia inicial con propanolol con o sin reemplazo de potasio endovenoso u oral, con monitoreo posterior adecuado que minimice el riesgo de hiperpotasemia de rebote.

Assessment of thyroid disorders in patients with rosacea: a large case-control study

Abstract Background: The frequency of autoimmune diseases and thyroid cancer has been increasingly reported in association with rosacea. However, studies investigating thyroid diseases in rosacea are scarce with conflicting results. Objective: To investigate the relationship between thyroid disorders and rosacea. Methods: A large case-control study on ageand gender-matched 2091 rosacea patients and 9572 controls was conducted. Rosacea patients using the rosacea-specific ICD codes were compiled from the hospital records. Additionally, all participants were evaluated in terms of the presence of hypothyroidism and hyperthyroidism. Conditional logistic regression analysis was used to compute case-control odds ratios (OR) with 95% confidence intervals. Results: The analysis comprehended 2091 rosacea patients (1546 female, 545 male; mean 48.73 ± 14.53 years) and 9572 controls (7009 female, 2563 male; mean 48.73 ± 15.1 years). Whereas the rate of hypothyroidism was significantly higher in rosacea patients (OR = 1.3, 95% CI 1.13-1.49, p < 0.001), there was no significant difference in the rate of hyperthyroidism between the groups (OR = 1.12, 95% CI 0.81-1.53, p = 0.497). Stratification for gender revealed a significant association between hypothyroidism and rosacea in females (OR = 1.27, 95% CI 1.1-1.47, p = 0.002) and males (OR = 1.58, 95% CI 1.04-2.4, p = 0.032). The frequency of hypothyroidism in rosacea patients increased towards the age range of 40-49 and then decreased, parallel with the hypothyroidism frequency of the study population. Study limitations: Different subtypes and severities of rosacea were not distinguished. Conclusions: Hypothyroidism may be a comorbidity of rosacea and investigation for hypothyroidism may be appropriate when evaluating rosacea patients.

Assessment of thyroid disorders in patients with rosacea: a large case-control study.

BACKGROUND: The frequency of autoimmune diseases and thyroid cancer has been increasingly reported in association with rosacea. However, studies investigating thyroid diseases in rosacea are scarce with conflicting results. OBJECTIVE: To investigate the relationship between thyroid disorders and rosacea. METHODS: A large case-control study on age- and gender-matched 2091 rosacea patients and 9572 controls was conducted. Rosacea patients using the rosacea-specific ICD codes were compiled from the hospital records. Additionally, all participants were evaluated in terms of the presence of hypothyroidism and hyperthyroidism. Conditional logistic regression analysis was used to compute case-control odds ratios (OR) with 95% confidence intervals. RESULTS: The analysis comprehended 2091 rosacea patients (1546 female, 545 male; mean 48.73 ± 14.53 years) and 9572 controls (7009 female, 2563 male; mean 48.73 ± 15.1 years). Whereas the rate of hypothyroidism was significantly higher in rosacea patients (OR = 1.3, 95% CI 1.13-1.49, p < 0.001), there was no significant difference in the rate of hyperthyroidism between the groups (OR = 1.12, 95% CI 0.81-1.53, p = 0.497). Stratification for gender revealed a significant association between hypothyroidism and rosacea in females (OR = 1.27, 95% CI 1.1-1.47, p = 0.002) and males (OR = 1.58, 95% CI 1.04-2.4, p = 0.032). The frequency of hypothyroidism in rosacea patients increased towards the age range of 40-49 and then decreased, parallel with the hypothyroidism frequency of the study population. STUDY LIMITATIONS: Different subtypes and severities of rosacea were not distinguished. CONCLUSIONS: Hypothyroidism may be a comorbidity of rosacea and investigation for hypothyroidism may be appropriate when evaluating rosacea patients.

Assessment of subclinical left ventricular dysfunction with speckle-tracking echocardiography in hyperthyroid and euthyroid Graves' disease and its correlation with serum TIMP-1.

BACKGROUND: Graves' disease has a multitude of effects on the cardiovascular system. In the detection of subclinical left ventricular dysfunction, speckle-tracking echocardiography is more useful than conventional echocardiography. The aim of the present study was to compare the longitudinal global strain values and venous blood concentration of (tissue inhibitor of metalloproteinase-1) TIMP-1, a regulator of the extracellular matrix, among hyperthyroid patients with Graves' disease, euthyroid patients with Graves' disease and healthy control subjects. MATERIALS AND METHODS: The study enrolled 40 hyperthyroid patients with newly diagnosed Graves' disease, 40 patients with Graves' disease who were euthyroid for at least 6 months and 40 control subjects with normal thyroid function. Participants underwent conventional echocardiography and speckle-tracking echocardiography to obtain segmental and global longitudinal strain values. In addition, the serum TIMP-1 value was assessed in the venous blood samples of the participants. RESULTS: The hyperthyroid Graves' patients showed greater serum TIMP-1 levels versus the control group and the euthyroid Graves' group. Compared to the control group, the TIMP-1 level was also significantly higher in the euthyroid Graves' group. Lower GLS (global longitudinal strain) average and GLS2C, GLS3C, GLS4C values were observed in both the hyperthyroid and euthyroid Graves' patients compared to the control group. The euthyroid Graves' patients and hyperthyroid Graves' patients had similar GLS values. The serum TIMP-1 level was negatively correlated with global strain values. CONCLUSION: Graves' disease coexists with impaired segmental and global longitudinal strain and increased TIMP-1 levels. This coexistence seems to be independent of serum thyroid hormone levels.

Association between Ménière's disease and thyroid diseases: a nested case-control study.

The association of thyroid disease and Ménière's disease would suggest that both are autoimmune diseases. This study aimed to investigate the relation of goiter, hypothyroidism, thyroiditis, hyperthyroidism, and autoimmune thyroiditis with Ménière's disease. The Korean National Health Insurance Service-Health Screening Cohort data from 2002 through 2015 were used. The 8183 adult patients with Ménière's disease were 1:4 matched with the 32,732 individuals of the control group for age, sex, income, and region of residence. The previous histories of thyroid disorders including goiter, hypothyroidism, thyroiditis, and hyperthyroidism were investigated using conditional logistic regression analyses. Subgroup analyses were conducted, including for age and sex. Smoking, alcohol consumption, obesity, Charlson Comorbidity Index, histories of benign paroxysmal vertigo, vestibular neuronitis, other peripheral vertigo, thyroid cancer, and levothyroxine medication were adjusted in the models. The histories of goiter (5.7% vs. 4.2%), hypothyroidism (4.7% vs. 3.6%), thyroiditis (2.1% vs. 1.6%), hyperthyroidism (3.6% vs. 2.5%), and autoimmune thyroiditis (0.99% vs. 0.67%) were higher in the Meniere's disease group than in the control group (all P < 0.05). The histories of goiter, hypothyroidism, and hyperthyroidism were associated with Ménière's disease (adjusted odds ratio (OR) = 1.19 [95% confidence interval (CI) = 1.04-1.36] for goiter, 1.21 [95% CI 1.02-1.44] for hypothyroidism, and 1.27 [95% CI 1.09-1.49] for hyperthyroidism, each of P < 0.05). In subgroup analyses, hypothyroidism was associated with Ménière's disease in < 65-year-old women. Hyperthyroidism was related with Ménière's disease in women overall. Thyroid diseases of goiter, hypothyroidism, and hyperthyroidism were associated with Ménière's disease.

Association between Sudden Sensorineural Hearing Loss and Preexisting Thyroid Diseases: A Nationwide Case-Control Study in Taiwan.

Background: Little evidence is available about the risk of sudden sensorineural hearing loss (SSNHL) in patients with thyroid diseases. We assessed whether a diagnosis of thyroid disease, particularly hyperthyroidism or hypothyroidism, is associated with SSNHL risk in an Asian population. Material and Methods: This case-control study was conducted with population-based data from Taiwan's National Health Insurance Research Database from January 2000 to December 2013. The case group comprised 3331 adult patients with newly diagnosed SSNHL, and four controls without SSNHL for each case matched by sex, age, monthly income, and urbanization level of residence. Underlying Thyroid diseases were retrospectively evaluated in the case and control groups. Multivariate logistic regression analyses were used to explore relations between thyroid diseases and SSNHL. Results: Of the 3331 cases, 5.7% had preexisting thyroid diseases, whereas only 4.0% of the 13,324 controls had the same condition. After adjustment for sex, age, monthly income, urbanization level of residence, history of hypertension, diabetes mellitus, chronic otitis media, and hyperlipidemia, associations were identified between a history of either hypothyroidism (adjusted odds ratio [AOR], 1.54; 95% CI, 1.02-2.32; p = 0.042) or hyperthyroidism (AOR, 1.41; 95% CI, 1.07-1.85; p = 0.015) and an elevated risk of SSNHL. In subgroup analysis, the correlation between hypothyroidism and increased SSNHL risk remained significant only for patients aged over 50 years (AOR, 1.61; 95% CI, 1.01-2.57; p = 0.045), and that between hyperthyroidism and SSNHL was significant only for female patients (AOR, 1.48; 95% CI, 1.09-2.01; p = 0.012). Treatment for hypothyroidism and hyperthyroidism did not alter the association in subgroup analyses. Conclusion: Preexisting hypothyroidism and hyperthyroidism appear associated with SSNHL susceptibility in Taiwan. Physicians should be wary of this elevated risk of SSNHL among patients with previously diagnosed thyroid dysfunction, especially women and patients aged more than 50 years.

Assessment of hormonal activity in patients with premature ejaculation

ABSTRACT Purpose Premature ejaculation is considered the most common type of male sexual dysfunction. Hormonal controls of ejaculation have not been exactly elucidated. The aim of our study is to investigate the role of hormonal factors in patients with premature ejaculation. Materials and Methods Sixty-three participants who consulted our outpatient clinics with complaints of premature ejaculation and 39 healthy men as a control group selected from volunteers were included in the study. A total of 102 sexual active men aged between 21 and 76 years were included. Premature ejaculation diagnostic tool questionnaires were used to assessment of premature ejaculation. Serum levels of follicle stimulating hormone, luteinizing hormone, prolactin, total and free testosterone, thyroid-stimulating hormone, free triiodothyronine and thyroxine were measured. Results Thyroid-stimulating hormone, luteinizing hormone, and prolactin levels were significantly lower in men with premature ejaculation according to premature ejaculation diagnostic tool (p=0.017, 0.007 and 0.007, respectively). Luteinizing hormone level (OR, 1.293; p=0.014) was found to be an independent risk factor for premature ejaculation. Conclusions Luteinizing hormone, prolactin, and thyroid-stimulating hormone levels are associated with premature ejaculation which was diagnosed by premature ejaculation diagnostic tool questionnaires. The relationship between these findings have to be determined by more extensive studies.

Assessment of hormonal activity in patients with premature ejaculation.

PURPOSE: Premature ejaculation is considered the most common type of male sexual dysfunction. Hormonal controls of ejaculation have not been exactly elucidated. The aim of our study is to investigate the role of hormonal factors in patients with premature ejaculation. MATERIALS AND METHODS: Sixty-three participants who consulted our outpatient clinics with complaints of premature ejaculation and 39 healthy men as a control group selected from volunteers were included in the study. A total of 102 sexual active men aged between 21 and 76 years were included. Premature ejaculation diagnostic tool questionnaires were used to assessment of premature ejaculation. Serum levels of follicle stimulating hormone, luteinizing hormone, prolactin, total and free testosterone, thyroid-stimulating hormone, free triiodothyronine and thyroxine were measured. RESULTS: Thyroid-stimulating hormone, luteinizing hormone, and prolactin levels were significantly lower in men with premature ejaculation according to premature ejaculation diagnostic tool (p=0.017, 0.007 and 0.007, respectively). Luteinizing hormone level (OR, 1.293; p=0.014) was found to be an independent risk factor for premature ejaculation. CONCLUSIONS: Luteinizing hormone, prolactin, and thyroid-stimulating hormone levels are associated with premature ejaculation which was diagnosed by premature ejaculation diagnostic tool questionnaires. The relationship between these findings have to be determined by more extensive studies.

Quantitative Assessment of Cardiac Function in Fetuses of Women with Maternal Gestational Thyroid Dysfunction Using VVI Echocardiography.

BACKGROUND: The study aimed to investigate the clinical value of velocity vector imaging (VVI) in assessing heart function in fetuses of pregnant women with thyroid dysfunction. The inter-observer and intra-observer variability was assessed for all VVI parameters observed. MATERIAL AND METHODS: The participants were enrolled from singleton pregnant women with gestational ages ranging 24+0 to 40+1 weeks who visited the Department of Obstetrics and Gynecology at the Affiliated Hospital of Qingdao University, China, for prenatal care from July 2011 to February 2014. Digital 2-dimensional (2D) dynamic 4-chamber images of the heart were collected. A total of qualified 226 images from 125 fetuses of pregnant women with normal thyroid (control group), 64 fetuses of pregnant women with hypothyroidism (hypothyroidism group), and 37 fetuses of pregnant women with hyperthyroidism (hyperthyroidism group) were interrogated offline using VVI software. The echocardiographic parameters including the myocardium peak systolic velocity (Vs), peak diastolic velocity (Vd), peak systolic strain (S), peak systolic strain rate (SRs), peak diastolic strain rate (SRd) of RV and LV, were obtained from the velocity curves of 2D myocardial motion. The heart rate was measured using a virtual M-mode algorithm built into the software. RESULTS: The study found that the longitudinal Vs and Vd of both ventricles in the control group gradually decreased from basal segments to apical segments and significantly increased over the gestation. S, SRs, and SRd of both ventricles remained stable after middle gestation. Compared with the control group, the hypothyroidism and hyperthyroidism groups exhibited significantly reduced S, SRs, and SRd, even for fetuses at 24-weeks gestation. There were no significant differences in global Vs and global Vd between the control group and the hyperthyroidism or hypothyroidism groups. CONCLUSIONS: The thyroid dysfunction of pregnant women may damage fetal heart function, and VVI could be a sensitive technique to measure the variation of fetal heart function.

The Fracture Risk Assessment Tool (FRAX score) in subclinical hyperthyroidism.

BACKGROUND/AIM: The Fracture Risk Assessment Tool (FRAX score) is the 10-year estimated risk calculation tool for bone fracture that includes clinical data and hip bone mineral density measured by dual-energy x-ray absorptiometry (DXA). The aim of this cross-sectional study was to elucidate the ability of the FRAX score in discriminating between bone fracture positive and negative pre- and postmenopausal women with subclinical hyperthyroidism. METHODS: The bone mineral density (by DXA), thyroid stimulating hormone (TSH) level, free thyroxine (fT4) level, thyroid peroxidase antibodies (TPOAb) titre, osteocalcin and beta-cross-laps were measured in 27 pre- and postmenopausal women with newly discovered subclinical hyperthyroidism [age 58.85 +/- 7.83 years, body mass index (BMI) 27.89 +/- 3.46 kg/m2, menopause onset in 46.88 +/- 10.21 years] and 51 matched euthyroid controls (age 59.69 +/- 5.72 years, BMI 27.68 +/- 4.66 kg/m2, menopause onset in 48.53 +/- 4.58 years). The etiology of subclinical hyperthyroisims was autoimmune thyroid disease or toxic goiter. FRAX score calculation was performed in both groups. RESULTS: In the group with subclinical hyperthyroidism the main FRAX score was significantly higher than in the controls (6.50 +/- 1.58 vs. 4.35 +/- 1.56 respectively; p = 0.015). The FRAX score for hip was also higher in the evaluated group than in the controls (1.33 +/- 3.92 vs. 0.50 +/- 0.46 respectively; p = 0.022). There was no correlations between low TSH and fracture risk (P > 0.05). The ability of the FRAX score in discriminating between bone fracture positive and negative pre- and postmenopausal female subjects (p < 0.001) is presented by the area under the curve (AUC) plotted via ROC analysis. The determined FRAX score cut-off value by this analysis was 6%, with estimated sensitivity and specificity of 95% and 75.9%, respectively. CONCLUSION: Pre- and postmenopausal women with subclinical hyperthyroidism have higher FRAX scores and thus greater risk for low-trauma hip fracture than euthyroid premenopausal women. Our results point to the use of FRAX calculator in monitoring pre- and postmenopausal women with subclinical hyperthyroidism to detect subjects with high fracture risk in order to prevent further fractures.

Left ventricular systolic intraventricular flow field assessment in hyperthyroidism patients using vector flow mapping.

Intraventricular hydrodynamics is considered an important component of cardiac function assessment. Vector flow mapping (VFM) is a novel flow visualization method to describe cardiac pathophysiological condition. This study examined use of new VFM and flow field for assessment of left ventricular (LV) systolic hemodynamics in patients with simple hyperthyroidism (HT). Thirty-seven simple HT patients were enrolled as HT group, and 38 gender- and age-matched healthy volunteers as control group. VFM model was used to analyze LV flow field at LV apical long-axis view. The following flow parameters were measured, including peak systolic velocity (Vs), peak systolic flow (Fs), total systolic negative flow (SQ) in LV basal, middle and apical level, velocity gradient from the apex to the aortic valve (ΔV), and velocity according to half distance (V1/2). The velocity vector in the LV cavity, stream line and vortex distribution in the two groups were observed. The results showed that there were no significant differences in the conventional parameters such as left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD) and left atrium diameter (LAD) between HT group and control group (P>0.05). Compared with the control group, a brighter flow and more vortexes were detected in HT group. Non-uniform distribution occurred in the LV flow field, and the stream lines were discontinuous in HT group. The values of Vs and Fs in three levels, SQ in middle and basal levels, ΔV and V1/2 were higher in HT group than in control group (P<0.01). ΔV was positively correlated with serum free thyroxin (FT4) (r=0.48, P<0.01). Stepwise multiple regression analysis showed that LVEDD, FT4, and body surface area (BSA) were the influence factors of ΔV. The unstable left ventricular systolic hydrodynamics increased in a compensatory manner in simple HT patients. The present study indicated that VFM may be used for early detection of abnormal ventricle contraction in clinical settings.

Risk assessment in the development of atrial fibrillation at patients with associate thyroid dysfunctions.

UNLABELLED: Thyroid hormones are an important regulator of cardiac function and vascular system. Atrial fibrillation is a common cardiac arrhythmia and an important risk factor for the ischemic cerebral vascular accident and heart failure. OBJECTIVES: The examination of the risk to develop atrial fibrillation in relation to the whole spectrum of thyroid dysfunctions. MATERIAL AND METHODS: All participants to our study were selected from among subjects with cardiovascular disorders whose hormonal thyroid status had been controlled previously and who hadn't been treated for thyroid functional disorders. Based on these criteria we defined a study lot made up of 791 subjects, 700 women and 91 men, aged between 22 to 86, with a mean age of approximately 60 years old, divided into five groups, based on the level of thyroid hormones. Once the lot was constituted, evaluations were made of the cardiovascular and thyroid condition at 6 and 12 months. RESULTS: During monitoring, most patients who developed atrial fibrillation were registered in the groups with manifest clinical hyperthyroidism, 34,62% and respectively with subclinical hypothyroidism, 38,6%. The main risk factors at the patients with manifest clinical hyperthyroidism were: female gender (RR=1.97) and age above 60 (RR=1.33), as well as the presence of coronary disease in the personal pathological record (RR=3.31), HBP (RR=1.46) and cardiac frequency in excess of 80 beats/min (RR=1.38). The main risk factors that led to atrial fibrillation among the patients with subclinical hypothyroidism, were: obesity (RR=2.21), the presence in the personal record of heart disease (RR=2,0), age over 60 (RR=1.90) and female sex (RR=1.30). At the patients who had been administered beta blockers prior to admission (RR=0.99), ACEI (RR=0.85) and/or antiarrythmic drugs (RR=0.54), the medication represented a protective factor against developing atrial fibrillation. CONCLUSIONS: Thyroid dysfunctions are associated with an increased risk to develop atrial fibrillation, both in the case of clinically manifest and the subclinical manifest forms. These results support long term screening for thyroid dysfunctions for patients with atrial fibrillation.

Vasopressinergic network abnormalities potentiate conditioned anxious state of rats subjected to maternal hyperthyroidism.

We have previously reported that a mild maternal hyperthyroidism in rats impairs stress coping of adult offspring. To assess anxiogenesis in this rat model of stress over-reactivity, we used two behavioural tests for unconditional and conditional anxious states: elevated plus maze test (EPM) and Vogel conflict test (VCT). In the latter one, arginine vasopressin (AVP) release was enhanced due to osmotic stress. With the EPM test no differences were observed between maternal hyperthyroid rats (MH) and controls. However, with the VCT, the MH showed increased anxiety-like behaviour. This behavioural difference was abolished by diazepam. Plasma AVP concentration curve as a function of water deprivation (WD) time showed a marked increase, reaching its maximal levels within half the time of controls and another significant difference after VCT. A general increase in Fos expression in hypothalamic supraoptic and paraventricular nuclei (PVN) was observed during WD and after VCT. There was also a significant increase of AVP immunoreactivity in anterior hypothalamic area. A large number of Herring bodies were observed in the AVP containing fibres of MH hypothalamic-neurohypophysial system. Numerous reciprocal synaptic connections between AVP and corticotropin releasing factor containing neurons in MH ventromedial PVN were observed by electron microscopy. These results suggest that a mild maternal hyperthyroidism could induce an aberrant organization in offspring's hypothalamic stress related regions which could mediate the enhanced anxiety seen in this animal model.

Hyperthyroidism and complete atrioventricular block--a report of 2 cases with electrophysiologic assessment.

Although cardiovascular manifestations in thyroid disorders are frequently encountered in clinical practice, atrioventricular (AV) conduction disorders, especially in hyperthyroidism, are rare. There are some proposed mechanisms for AV blocks in hyperthyroidism but the exact mechanism is still unknown. The authors report 2 cases with thyroid function disorders and complete AV block, and the electrophysiologic characteristics of these 2 patients, and they review and speculate on similar reported cases.

Yield of laboratory testing to identify secondary contributors to osteoporosis in otherwise healthy women.

Our purpose in this study was to determine the prevalence of undetected disorders of bone and mineral metabolism in women with osteoporosis and to identify the most useful and cost-efficient screening tests to detect these disorders. A cross-sectional study was conducted among 664 postmenopausal women with osteoporosis at the Osteoporosis and Metabolic Bone Disease Program at the Mount Sinai Hospital in New York between January 1992 and June 1996. Women without a history of diseases or medications known to adversely affect bone who completed extensive laboratory testing including complete blood count, chemistry profile, 24-h urinary calcium, 25(OH)vitamin D, and PTH were included. Among 173 women who met the inclusion criteria for the study, previously undiagnosed disorders of bone and mineral metabolism were identified in 55 women (32%). Disorders of calcium metabolism and hyperparathyroidism were the most frequent diagnoses. A testing strategy involving measurement of 24-h urine calcium, serum calcium, and serum PTH for all women and serum TSH among women on thyroid replacement therapy would have been sufficient to diagnose 47 of these 55 women (85%) at an estimated cost of $75 per patient screened. Previously undiagnosed disorders affecting the skeleton are common in otherwise healthy women with low bone density. A simple testing strategy is likely to identify most such disorders.