Evaluation of left ventricular diastolic function using tissue Doppler echocardiography and conventional doppler echocardiography in patients with subclinical hypothyroidism aged <60 years: A meta-analysis

Myxedema ascites? A rare presentation of ascites in severe hypothyroidism: A case report and review

Ascites represents an infrequent sequela of hypothyroidism, manifesting in fewer than 4% of affected individuals. Herein, we delineate a case characterized by profound hypothyroidism accompanied by substantial ascites, further complicated by cardiac insufficiency. A 29-year-old female, previously diagnosed with postradiation hypothyroidism subsequent to a diagnosis of Grave's disease 11 years prior, presented with exacerbating dyspnoea, abdominal distension, and orthopnea. In January 2024, she was admitted with massive ascites, exhibiting clinical manifestations of both hypothyroidism and cardiac failure. Thyroid function tests were markedly abnormal, with a thyroid-stimulating hormone level of 77.65 mIU/L, triiodothyronine at 2.2 nmol/L, and thyroxine levels below 3.2 pmol/L. Echocardiographic evaluation revealed dilated cardiomyopathy with a significantly reduced systolic (ejection fraction of 25.9%) and diastolic function (E/A ratio of 0.87). Analysis of the ascitic fluid demonstrated a serum-ascites albumin gradient exceeding 1.1 g/L (3 g/L). Ultrasonography of the abdomen ruled out portal hypertension, while computed tomography of the abdomen confirmed extensive ascites without evidence of malignancy. Under the supervision of a specialist, the patient was administered a high dosage of levothyroxine (300 mcg), leading to a significant amelioration in both thyroid function parameters and her ascites. Subsequent thyroid function tests demonstrated a decrease in thyroid-stimulating hormone levels to 11.7 mIU/L and an increase in thyroxine levels to 15.6 pmol/L, indicating a positive response to the thyroid hormone replacement therapy. Subsequent echocardiographic assessment showed improvement in the ejection fraction to 26.9% and diastolic function (E/A ratio of 1.27). Myxedema ascites, though infrequent, is readily amenable to treatment. The serum-ascites albumin gradient exceeding 1.1 g/L may be indicative of hypothyroidism-associated ascites, although the paucity of studies renders it uncertain whether this is a characteristic feature. Further investigation into the etiology, diagnostic criteria, and management strategies for ascites in the context of hypothyroidism is warranted.

The association between TSH and thyroid hormones in the normal or subclinical dysfunction range with left ventricular diastolic dysfunction

Thyroid hormones modulate the cardiovascular system. However, the effects of subclinical thyroid dysfunction and euthyroidism on cardiac function remain unclear. We investigated the association between left ventricular (LV) diastolic dysfunction and subclinical thyroid dysfunction or thyroid hormones within the reference range. This cross-sectional study included 26,289 participants (22,197 euthyroid, 3,671 with subclinical hypothyroidism, and 421 with subclinical thyrotoxicosis) who underwent regular health check-ups in the Republic of Korea. Individuals with thyroid stimulating hormone (TSH) levels > 4.2 µIU/mL and normal free thyroxine (FT4, 0.78-1.85 ng/dL) and triiodothyronine (T3, 76-190 ng/dL) levels were defined as having subclinical hypothyroidism. Individuals with serum TSH levels < 0.4 µIU/mL and normal FT4 and T3 levels were defined as having subclinical thyrotoxicosis. The cardiac structure and function were evaluated using echocardiography. LV diastolic dysfunction with normal ejection fraction (EF) was defined as follows: EF of > 50% and (a) E/e' ratio > 15, or (b) E/e' ratio of 8-15 and left atrial volume index ≥ 34 mL/m2. Subclinical hypothyroidism was significantly associated with cardiac indices regarding LV diastolic dysfunction. The odds of having LV diastolic dysfunction was also increased in participants with subclinical hypothyroidism (adjusted odds ratio [AOR] 1.36, 95% confidence interval [CI], 1.01-1.89) compared to euthyroid participants. Subclinical thyrotoxicosis was not associated with LV diastolic dysfunction. Among the thyroid hormones, only serum T3 was significantly and inversely associated with LV diastolic dysfunction even within the normal range. Subclinical hypothyroidism was significantly associated with LV diastolic dysfunction, whereas subclinical thyrotoxicosis was not. Serum T3 is a relatively important contributor to LV diastolic dysfunction compared to TSH or FT4.

The association between dyslipidaemia in the first trimester and adverse pregnancy outcomes in pregnant women with subclinical hypothyroidism: a cohort study

BACKGROUND

Subclinical hypothyroidism (SCH) is linked to dyslipidaemia and adverse pregnancy outcomes. However, the impact of dyslipidaemia on the outcome of pregnancy in SCH is unclear.

METHODS

We enrolled 36,256 pregnant women and evaluated their pregnancy outcomes. The following data was gathered during the first trimester (≤ 13+ 6 weeks of gestation): total cholesterol (TC), low-density lipoprotein (LDL-C), triglyceride (TG), high-density lipoprotein (HDL-C), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) concentrations. The reference ranges for lipids were estimated to range from the 5th to the 95th percentile. Logistic regression assessed the relationships between dyslipidaemia and adverse pregnancy outcomes, including abortion, preeclampsia/eclampsia, low birth weight, foetal growth restriction, premature rupture of foetal membranes, gestational hypertension, preterm birth, macrosomia and gestational diabetes mellitus (GDM). Additionally, the best thresholds for predicting adverse pregnancy outcomes based on TSH, FT4, and lipid levels were determined using receiver operating characteristic curves.

RESULTS

In the first trimester, LDL-C > 3.24 mmol/L, TG > 1.92 mmol/L, HDL-C < 1.06 mmol/L, and TC > 5.39 mmol/L were used to define dyslipidaemia. In this cohort, 952 (3.56%) patients were diagnosed with SCH, and those who had dyslipidaemia in the first trimester had higher incidences of gestational hypertension (6.59% vs. 3.25%), preeclampsia/eclampsia (7.14% vs. 3.12%), GDM (22.53% vs. 13.77%), and low birth weight (4.95% vs. 2.08%) than did those without dyslipidaemia. However, after adjusting for prepregnancy body mass index (pre-BMI), dyslipidaemia was no longer related to these risks. Furthermore, elevated TG dyslipidaemia in SCH patients was connected to an enhanced potential of gestational hypertension (odds ratio [OR]: 2.687, 95% confidence interval [CI]: 1.074 ~ 6.722), and elevated LDL-C dyslipidaemia correlated with increased preeclampsia/eclampsia risk (OR: 3.172, 95% CI: 1.204 ~ 8.355) after accounting for age, smoking status, alcohol use, pre-BMI, and levothyroxine use. Additionally, the combination of TC, TG, LDL-C, pre-BMI, and TSH exhibited enhanced predictive capabilities for gestational hypertension, preeclampsia/eclampsia, and GDM. Values of 0.767, 0.704, and 0.706 were obtained from the area under the curve.

CONCLUSIONS

Among pregnant women with SCH, dyslipidaemia in early pregnancy was related to elevated risks of adverse pregnancy consequences. The combined consideration of age, pre-BMI, TSH, and lipid levels in the first trimester could be beneficial for monitoring patients and implementing interventions to reduce adverse pregnancy outcomes.

Effect of thyroid hormone replacement treatment on cardiac diastolic function in adult patients with subclinical hypothyroidism: a meta-analysis

Background

Although subclinical hypothyroidism (SCH) is related to abnormalities in left ventricular diastolic function, the use of levothyroxine as a regular treatment remains debatable. This meta-analysis aimed to determine whether thyroid hormone replacement therapy affects cardiac diastolic function in patients with SCH as measured by echocardiography.

Methods

This meta-analysis included a search of the EMBASE, PubMed, Web of Science, and Cochrane Library databases from their inception to May 18, 2023, for studies analyzing cardiac morphology and functional changes in patients with SCH before and after thyroid hormone replacement. The outcome measures were cardiac morphology and diastolic and overall cardiac function, as assessed using ultrasound parameters (including ventricular wall thickness, chamber size, mitral wave flow, tissue Doppler, and speckle tracking). The quality of the studies was assessed using the Newcastle-Ottawa Scale. The standard mean differences (MDs) and 95% confidence intervals (CI) were calculated using fixed- or random-effects models.

Results

Seventeen studies met the inclusion criteria. A total of 568 patients participated and completed the follow-up. All studies specifically stated that serum thyrotropin levels returned to normal by the end of the study period. Compared with baseline levels, no significant morphological changes were observed in the heart. In terms of diastolic function, we discovered that the ratios of E-velocity to A-velocity (E/A) had greatly improved after thyroid hormone replacement therapy, whereas the ratios of the mitral inflow E wave to the tissue Doppler e' wave (E/e') had not. Global longitudinal strain (GLS) increased significantly after treatment with levothyroxine.

Conclusion

In adult patients with SCH, thyroid hormone supplementation can partially but not completely improve parameters of diastolic function during the observation period. This meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement, an updated guideline for reporting systematic reviews (11) and was registered with INPLASY (INPLASY202320083).

Systematic review registration

https://inplasy.com/inplasy-2023-2-0083.

[Prospective evaluation of radiation-induced thyroid disorders after breast and supraclavicular irradiation]

PURPOSE

The thyroid is an endocrine gland playing a major role in metabolism and development by the secretion of T4 and T3 thyroid hormones. Due to its anatomical position, it is often included in the target volume for the irradiation of certain tumours and thus receives significant doses (10 to 80Gy). The treatment of breast cancer requires in most cases a breast irradiation associated or not with a lymph node irradiation. The aim of our study was to investigate prospectively the frequency of thyroid disorders in patients with breast cancer treated by radiation, with or without irradiation of the supra- and subclavicular lymph nodes.

MATERIAL AND METHODS

This prospective multicentre study (institut Godinot, institut de cancérologie Strasbourg Europe and institut de cancérologie de Lorraine) concerned adult patients with non-metastatic breast carcinoma treated by adjuvant irradiation. They were included in a non-randomized way between February 2013 and June 2015 and divided into two groups according to treatment: (i) breast radiotherapy associated with irradiation of the supra- and subclavicular lymph nodes (group 1), or (ii) breast irradiation alone (group 2). The dose - volume histogram of the thyroid was systematically edited by the physics department. Each patient had a consultation with an endocrinologist at the beginning of the treatment and was monitored by blood analyses including TSH, T4L, antithyroglobulin and antiperoxidase antibodies every 6 months until the 60th month after the end of radiotherapy. Data were described by numbers and percentages for qualitative variables; by means, medians, standard deviation and ranges for quantitative variables. Statistical associations were tested by Chi2, Fisher's, Student's, or analysis of variance tests depending on the conditions of application. Survival analyses were performed by log rank tests and Cox models.

RESULTS

This study initially included 500 patients, 245 in group 1 and 252 in group 2 (three patients were later excluded for false inclusion). Thyroid abnormalities occurred in 76 patients, representing an incidence of 15.3%. The mean time of the first occurrence of thyroid disorders was 24.3 months. It was more frequent in group 1 with a prevalence of 19.2% against 11.5% in group 2 (P=0.01745). A maximal radiation dose delivered to the thyroid gland greater than 20Gy (odds ratio [OR]: 1.82; P=0.018) or 30Gy (OR: 1.89; P=0.013) was significantly associated with a higher incidence of thyroid disorders, as was a mean dose greater than 30Gy (OR: 5.69; P=0.049). A percentage of thyroid volume receiving 30Gy (V30) greater than 50% (P=0.006) or greater than 62.5% (P=0.021) was significantly associated with an increased incidence of thyroid disorder and more precisely, hypothyroidism (P=0.0007). In multivariate analysis, no factor associated with the occurrence of thyroid disorder was identified. However, in the subgroup analysis concerning group 1 (receiving supraclavicular irradiation), a maximal radiation dose greater than 30Gy appeared to be a risk factor for the occurrence of thyroid disorders (P=0.040).

CONCLUSION

Thyroid disorder, and in particular hypothyroidism, may be a late side effect of locoregional breast radiotherapy. Patients receiving this treatment should have a biological monitoring of thyroid function.

Subclinical hypothyroidism, outcomes and management guidelines: a narrative review and update of recent literature

Subclinical hypothyroidism (SCH) is diagnosed when serum thyroid stimulation hormone (thyrotropin; TSH) levels are above the reference range, accompanied by levels of free thyroxine within its reference range. The management of SCH remains a diagnostic and therapeutic challenge despite many years of research relating to its epidemiology, aetiology, effectiveness of treatment and safety. European Thyroid Association (ETA) guidelines for the management of SCH were published almost a decade ago. This narrative review summarizes the clinical literature relating to SCH and outcomes since the publication of these guidelines. Clinical evidence emerging during the previous decade generally supports the view that SCH is associated with adverse outcomes to an extent that is intermediate between euthyroidism and overt hypothyroidism although evidence that treatment with thyroid hormone replacement is beneficial is lacking. Accordingly, the rationale for the recommendations for intervention in the ETA guidelines based on the age of the patient, level of serum TSH, symptoms and comorbidities remains valid today.

Down syndrome patients with normal hearts: are they really normal?

Even though congenital heart disease is a common finding in down syndrome (DS) patients, some of them have anatomically normal hearts. However, the term "normal" might not be suitable, as these patients usually suffer from functional cardiac dysfunction. Several research highlighted that despite the absence of anatomical heart defects, subtle cardiac function derangements are present in DS patients. We aim to assess cardiac functions by Two-dimensional echocardiography and tissue Doppler imaging (TDI) in pediatric DS patients who have anatomically normal hearts. One hundred seventy-two patients with karyotyping confirmed DS with anatomically normal hearts and 165 healthy normal control children were enrolled in the current study. Their cardiac functions were assessed using both 2-dimensional echocardiography and TDI. Both patients and controls had structurally and anatomically normal hearts. In DS patients, the right side of the heart showed a significant reduction in both systolic and diastolic functions. Systolic dysfunction was evident by significantly decreased levels of Tricuspid annular plane systolic excursion and systolic wave by TDI. Diastolic dysfunction of the right ventricle was evident by prolonged deceleration time by conventional echocardiography and a significant decrease in annular tissue doppler velocity during early diastole/late diastole ratio by TDI. The E/De ratio was significantly increased. Even with anatomically normal hearts, DS patients should undergo cardiac function assessment by echocardiography & TDI. TDI is superior to conventional echocardiography in detecting subtle cardiac dysfunction especially left ventricular diastolic dysfunction in DS patients. TDI showed a significant decrease in the early/atrial ratio of mitral valve annulus and prolongation of left ventricle isometric relaxation time in DS children. Also, the left ventricle E/De ratio was prolonged denoting elevated filling pressures and diastolic dysfunction. This indicates that the TDI has higher sensitivity to detect diastolic dysfunction than conventional Echocardiography. Biventricular TDI-derived myocardial performance index was found to be significantly increased in DS children.

Non-medicalization of medical science: Rationalization for future

As we delve into the intricacies of human disease, millions of people continue to be diagnosed as having what are labelled as pre-conditions or sub-clinical entities and may receive treatments designed to prevent further progression to clinical disease, but with debatable impact and consequences. Endocrinology is no different, with almost every organ system and associated diseases having subclinical entities. Although the expansion of these “grey” pre-conditions and their treatments come with a better understanding of pathophysiologic processes, they also entail financial costs and drug adverse-effects, and lack true prevention, thus refuting the very foundation of Medicine laid by Hippocrates “Primum non nocere” (Latin), i.e., do no harm. Subclinical hypothyroidism, prediabetes, osteopenia, and minimal autonomous cortisol excess are some of the endocrine pre-clinical conditions which do not require active pharmacological management in the vast majority. In fact, progression to clinical disease is seen in only a small minority with reversal to normality in most. Giving drugs also does not lead to true prevention by changing the course of future disease. The goal of the medical fraternity thus as a whole should be to bring this large chunk of humanity out of the hospitals towards leading a healthy lifestyle and away from the label of a medical disease condition.

Effect of Levothyroxine Supplementation on the Cardiac Morphology and Function in Patients With Subclinical Hypothyroidism: A Systematic Review and Meta-analysis

CONTEXT

The impact of abnormal thyroid hormone levels on the cardiovascular system has been explored for decades. Recent emerging evidence suggests that subclinical thyroid dysfunction, especially subclinical hypothyroidism (SCH), significantly affects cardiac indices.

OBJECTIVE

We aimed to determine whether levothyroxine (LT4), commonly used to treat hypothyroidism, affects cardiovascular indices in SCH patients.

METHODS

This is a systematic review and meta-analysis. We searched online databases for studies analyzing cardiac morphology and functional changes in SCH patients before and after LT4 supplementation. A total of 294 SCH patients participated and finished the follow-up. The standard mean difference and 95% CI were calculated in fixed or random-effects models. The clinical outcomes analyzed in this study included 18 indicators, mainly covering cardiac morphology, myocardial performance (including various indicators of systolic and diastolic function), mitral wave flow, and systemic vascular resistance.

RESULTS

A total of 11 studies met our search criteria. All studies explicitly mentioned that serum thyrotropin levels decreased to normal at follow-up. Our results suggest that the cardiac output (CO), left ventricular ejection fraction (LVEF), and the ratio of peak E velocity/peak A velocity were all significantly increased after LT4 supplementation compared with the baseline level. However, we found no clear evidence of significant morphological changes in the heart.

CONCLUSION

Judging from the obvious changes in the CO, LVEF, and E/A ratio, LT4 supplementation can effectively improve the cardiac systolic and diastolic dysfunction prevalent in SCH patients. This study provides evidence of the recommendation for LT4 supplementation in adult SCH patients.

[Subclinical hypothyroidism]

Subclinical hypothyroidism is usually a laboratory diagnosis without significant symptoms and is defined by an elevated thyroid-stimulating hormone (thyrotropin, TSH) with normal thyroid hormone levels. On laboratory checks after two to three months, spontaneous normalization is found in 50 % of all cases in the sense of a transient elevation.With persistently elevated TSH levels, subclinical hypothyroidism is associated with evidence of thyroid-specific antibodies in the sense of autoimmune thyroiditis. Physiologically higher TSH levels are found in old age. It can therefore be assumed that the diagnosis of subclinical hypothyroidism is made and treated too frequently in older people over 70 years of age.Studies have so far failed to show a positive effect of substitution therapy of subclinical hypothyroidism, especially in elderly patients. On the other hand, there is a not inconsiderable risk of overtreatment with the development of subclinical hyperthyroidism. Its negative consequences in the form of atrial fibrillation and osteoporosis impair the quality and duration of life. Therefore, the indication for substitution therapy of subclinical hypothyroidism should be made with caution.One group in which diagnosis and therapy require special sensitivity is pregnant women. Here, two individuals, mother and child, must be treated. Varying target values and dosages in relation to the gestational age must be taken into account.

The Association between Thyroid-Stimulating Hormone and Long-Term Outcomes in Patients with ST Segment Elevation Myocardial Infarction Treated by Primary Percutaneous Coronary Intervention

Objective

Thyroid hormones are closely related to the cardiovascular system. Our study aimed to explore the impact of admission thyroid-stimulating hormone (TSH) levels on long-term outcomes in patients with acute ST segment elevation myocardial infarction (STEMI) by detailed stratifications of TSH.

Methods

Consecutive STEMI patients admitted to our hospital were divided into four groups: Group 1 (TSH <0.35 mIU/L), Group 2 (TSH 0.35–1.0 mIU/L), Group 3 (TSH 1.0–3.5 mIU/L), and Group 4 (TSH >3.5 mIU/L). The primary endpoint was all-cause mortality during follow-up, and the median follow-up was 2.5 years. Cox proportional hazard regression models were performed to identify the prognostic value of TSH.

Results

A total of 1186 patients were included. Group 4 was presented with higher systolic and diastolic blood pressure (all P < 0.001), and Group 1 had more patients complicated by heart failure (Killip class >I, P = 0.014). During follow-up, 138 deaths occurred. Patients in Group 4 had the worst long-term outcomes (P < 0.001). The cumulative survival in Group 4 was remarkably lower (Log rank P < 0.001), whereas the other three groups were comparable (Log rank P = 0.365). Through Cox regression analysis, only TSH >3.5 mIU/L was identified as an independent risk factor for long-term mortality after STEMI.

Conclusion

Only TSH elevation beyond the normal range was associated with worse long-term prognosis in STEMI patients, while high-normal TSH or reduced TSH did not alter long-term prognosis of STEMI patients. TSH >3.5 mIU/L was an independent risk factor for long-term mortality in STEMI.

The association of presystolic wave with subclinical left-ventricular dysfunction in patients with subclinical hypothyroidism

PURPOSE

Subclinical hypothyroidism (SCH) patients develop left-ventricular dysfunction (LVD) in an earlier stage. LVD could be detected with myocardial performance index (MPI), left -ventricular global longitudinal strain (LVGLS), and conventional and tissue-Doppler imaging (TDI). A presystolic wave (PSW) detected on late diastole is associated with LVD. We aimed to determine whether there is an association between PSW and subclinical LVD assessed by different echocardiographic methods in SCH patients.

METHODS

We prospectively enrolled 105 patients diagnosed with SCH in this study. Patients were divided into two groups based on the presence of PSW. Both groups were compared with respect to demographic, clinical, and echocardiographic properties. Multivariable regression analysis was performed to detect predictors of subclinical LVD.

RESULTS

The study included 70 PSW-positive patients (66%, mean age: 50.2) and 35 PSW-negative patients (34%, mean age: 46.5). PSW-positive patients had a lower platelet and a higher RDW level compared to PSW-negative patients. PSW-positive patients had more frequent subclinical LVD, which was assessed by MPI, by conventional and TDI parameters, and by LVGLS. PSW velocity was significantly correlated with MPI velocity (r = 0.31, p = 0.009), TSH level (r = 0.44, p < 0.001), and with LVGLS (r = 0.33, p = 0.005). The presence of PSW was an independent predictor of subclinical LVD in multivariable logistic regression analysis detected with MPI, LVGLS, and TDI parameters (OR = 5.409, p = 0.03; OR = 4.872, p = 0.005; OR = 5.632, p = 0.014, respectively).

CONCLUSION

PSW prevalence was 66% in SCH patients. PSW velocity was significantly correlated with MPI and LVGLS. The presence of PSW was independently associated with subclinical LVD in SCH patients.

Complications during chronic total occlusion percutaneous coronary intervention: a sign- and symptom-based approach to early diagnosis and treatment

Coronary chronic total occlusions (CTO) are frequently found in patients undergoing coronary angiography. Despite their high prevalence and indication for revascularization in a relevant proportion of cases, CTO recanalization is attempted only in a minority of cases. This is due to higher risk of procedural complications compared to non-CTO interventions and because the CTO-PCIs are the most complex procedures in interventional cardiology. In particular, the perceived higher risk of complications during CTO intervention might discourage new operators from engaging in this challenging field. The aim of this work is to review the potential complications of CTO percutaneous coronary intervention, and to provide an algorithmic, sign- and symptom-based approach to facilitate early recognition and effective management.

A Clinical Debate: Subclinical Hypothyroidism

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Subclinical Hypothyroidism: Prevalence, Health Impact, and Treatment Landscape

Subclinical hypothyroidism (sHypo) is defined as normal serum free thyroid hormone levels coexisting with elevated serum thyroid-stimulating hormone (TSH) levels. sHypo is a common condition observed in clinical practice with several unique features. Its diagnosis should be based on an understanding of geographic and demographic differences in biochemical criteria versus a global reference range for TSH that is based on the 95% confidence interval of a healthy population. During the differential diagnosis, it is important to remember that a considerable proportion of sHypo cases are transient and reversible in nature; the focus is better placed on persistent or progressive forms, which mainly result from chronic autoimmune thyroiditis. Despite significant evidence documenting the health impacts of sHypo, the effects of levothyroxine treatment (LT4-Tx) in patients with sHypo remains controversial, especially in patients with grade 1 sHypo and older adults. Existing evidence suggests that it is reasonable to refrain from immediate LT4-Tx in most patients if they are closely monitored, except in women who are pregnant or in progressive cases. Future research is needed to further characterize the risks and benefits of LT4-Tx in different patient cohorts.

Evaluation of Thyroid Function in Patients Hospitalized for Acute Heart Failure

BACKGROUND

Thyroid hormones (TH) are crucial for cardiovascular homeostasis. Recent evidence suggests that acute cardiovascular conditions, particularly acute heart failure (AHF), significantly impair the thyroid axis. Our aim was to evaluate the association of thyroid function with cardiovascular parameters and short- and long-term clinical outcomes in AHF patients.

METHODS

We performed a single-centre retrospective cohort study including patients hospitalized for AHF between January 2012 and December 2017. We used linear, logistic, and Cox proportional hazard regression models to analyse the association of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) with inpatient cardiovascular parameters, in-hospital mortality, short-term adverse clinical outcomes, and long-term mortality. Two models were used: (1) unadjusted, and (2) adjusted for age and sex.

RESULTS

Of the 235 patients included, 59% were female, and the mean age was 77.5 (SD 10.4) years. In the adjusted model, diastolic blood pressure was positively associated with TSH [β = 2.68 (0.27 to 5.09); p = 0.030]; left ventricle ejection fraction (LVEF) was negatively associated with FT4 [β = -24.85 (-47.87 to -1.82); p = 0.035]; and a nonsignificant trend for a positive association was found between 30-day all-cause mortality and FT4 [OR = 3.40 (0.90 to 12.83); p = 0.071]. Among euthyroid participants, higher FT4 levels were significantly associated with a higher odds of 30-day all-cause death [OR = 4.40 (1.06 to 18.16); p = 0.041]. Neither TSH nor FT4 levels were relevant predictors of long-term mortality in the adjusted model.

CONCLUSIONS

Thyroid function in AHF patients is associated with blood pressure and LVEF during hospitalization. FT4 might be useful as a biomarker of short-term adverse outcomes in these patients.

Chronic total occlusion percutaneous coronary intervention: managing perforation complications

INTRODUCTION

Coronary artery perforation (CAP) is an infrequent (<1%) complication of percutaneous coronary intervention (PCI), that can lead to dramatic consequences, including tamponade and death. The incidence of CAP is higher (4-9%) in chronic total occlusion (CTO) PCI due higher complexity of these lesions and the techniques used to recanalized them.

AREAS COVERED

In this Expert Review, we discuss the specific features of CTO PCI predisposing to CAP. We also describe the typical procedural scenarios in which CAP can occur and provide a universal management algorithm. Currently available devices and techniques for CAP treatment are presented in detail. Finally, we discuss imaging support for diagnosis of pericardial effusion in CAP as well as medical and surgical management.

EXPERT OPINION

With increasing volumes and complexity of CTO PCI, the incidence of CAP is likely to rise. Adherence to good catheterization laboratory practices, availability of dedicated equipment to seal CAP, perform pericardiocentesis, and provide hemodynamic support, as well as adequate training, are pillars for the prevention and optimal management of CAP during CTO PCI.

Association of Thyroid Hormone Therapy with Mortality in Subclinical Hypothyroidism: A Systematic Review and Meta-Analysis

CONTEXT

Benefits of thyroid hormone therapy on mortality in adults with subclinical hypothyroidism remain undetermined.

OBJECTIVE

To summarize the impact of thyroid hormone therapy on mortality in adults with subclinical hypothyroidism.

DATA SOURCES

PubMed, Embase, Scopus, Web of Science, and Clinicaltrials.gov from inception until April 25, 2020.

STUDY SELECTION

Studies comparing the effect of thyroid hormone therapy with that of placebo or no therapy in adults with subclinical hypothyroidism on all-cause and/or cardiovascular mortality.

DATA EXTRACTION

Two reviewers independently extracted data and performed quality assessments. Random-effects models for meta-analyses were used.

DATA SYNTHESIS

Five observational studies and 2 randomized controlled trials with 21 055 adults were included. Overall, thyroid hormone therapy was not significantly associated with all-cause (pooled relative risk [RR] = 0.95, 95% confidence interval [CI]: 0.75-1.22, P = .704) or cardiovascular (pooled RR = 0.99, 95% CI: 0.82-1.20, P = .946) mortality. Subgroup analyses revealed that in younger adults (aged <65-70 years), thyroid hormone therapy was significantly associated with a lower all-cause (pooled RR = 0.50, 95% CI: 0.29-0.85, P = .011) and cardiovascular (pooled RR = 0.54, 95% CI: 0.37-0.80, P = .002) mortality. However, no significant association between thyroid hormone therapy and mortality was observed in older adults (aged ≥65-70 years).

CONCLUSIONS

Use of thyroid hormone therapy does not provide protective effects on mortality in older adults with subclinical hypothyroidism. However, thyroid hormone therapy for subclinical hypothyroidism may show benefits on morality in adults aged <65 to 70 years.

No association between subclinical hypothyroidism and dyslipidemia in children and adolescents

Background

There are controversies about the correlation between higher levels of thyroid stimulating hormone (TSH) and dyslipidemia in children. This study was designed to assess the relation between lipid profile components and TSH levels in children.

Method

This cross-sectional study was performed in a pediatric endocrinology growth assessment clinic in Shiraz, southern Iran. Children aged 2–18 years who referred to the clinic from January until April 2018 were included. TSH levels equal or above 5 mIU/L and lower than 10 mIU/L with normal free T4 (FT4) were considered as having subclinical hypothyroidism (SH).

Results

Six hundred sixty-six children were euthyroid while 181 had SH. No significant difference was found between the mean serum total cholesterol (P = 0.713), LDL-C (P = 0.369), HDL-C (P = 0.211), non-HDL-C (P = 0.929), and triglyceride (P = 0.215) levels between euthyroid children and subjects with SH. There was also no significant difference in the prevalence of dyslipidemias in any lipid profile components between the two groups. The adjusted correlation was not significant between TSH levels and any lipid profile component.

Conclusion

Based on the results of our study, we found no correlation between SH and dyslipidemia in children. The association between dyslipidemia and SH in children still seems to be inconsistent based on the results of this and previous studies. We recommend a meta-analysis or a significantly larger retrospective study on this subject.

Left and right ventricular functions may be impaired in children diagnosed with subclinical hypothyroidism

Subclinical hypothyroidism (SH) may influence both ventricular functions. The aim of this study was to evaluation the findings of Tissue Doppler Imaging (TDI) and other echocardiography modalities in children with SH. We compared left ventricular mass index (LVMI) and TDI parameters of patients with SH and children with euthyroidism. Subclinical hypothyroidism was diagnosed when thyroid stimulating hormone level was higher than the reference value of the laboratory (> 4.2 mIU/L) and free thyroxine level was in normal range. The study included a group of 35 patients with SH and a control group of 38 children with euthyroidism (mean age was 7.6 ± 3.5 years and 9.0 ± 2.4 years, respectively). LVMI was significantly higher in the patient group (p = 0.005). TDI parameters including mitral septal ejection time was lower (p = 0.003) and mitral septal myocardial performance index was higher (p = 0.009) in the patient group. Right ventricular TDI revealed that tricuspid lateral E/Ea and tricuspid septal E/Ea were higher (p = 0.015 and p = 0.024, respectively) and tricuspid septal Ea/Aa and ejection time were lower (p = 0.018 and p = 0.017, respectively) in the patient group. SH may lead to increase LVMI. Left ventricular systolic and diastolic TDI parameters (lower mitral septal ejection time, higher mitral septal myocardial performance index) as well as right ventricular systolic (lower tricuspid septal ejection time) and diastolic (higher tricuspid septal and lateral E/Ea, lower tricuspid septal Ea/Ea) functions may be also impaired in children with subclinical hypothyroidism. TDI is a useful method used for the assessment of the effect of SH on cardiac functions.

Left Ventricular Diastolic and Systolic Functions in Patients with Hypothyroidism

Background and objectives: Long standing hypothyroidism may impair myocardial relaxation, but its effect on systolic myocardial function is still controversial. The aim of this study was to investigate left ventricular (LV) systolic and diastolic function in patients with hypothyroidism. Materials and Methods: This study included 81 (age 42 ± 13 years, 92% female) patients with hypothyroidism, and 22 age and gender matched controls. All subjects underwent a detailed clinical examination followed by a complete biochemical blood analysis including thyroid function assessment and anthropometric parameters measurements. LV function was assessed by 2-dimensional, M-mode and Tissue-Doppler Doppler echocardiographic examination performed in the same day. Results: Patients had lower waist/hip ratio (p< 0.001), higher urea level (p = 0.002), and lower white blood cells (p = 0.011), compared with controls. All other clinical, biochemical, and anthropometric data did not differ between the two groups. Patients had impaired LV diastolic function (lower E wave [p< 0.001], higher A wave [p = 0.028], lower E/A ratio [p< 0.001], longer E wave deceleration time [p = 0.01], and higher E/e' ratio [p< 0.001]), compared with controls. Although LV global systolic function did not differ between groups, LV longitudinal systolic function was compromised in patients (lateral mitral annular plane systolic excursion-MAPSE [p = 0.005], as were lateral and septal s' [p< 0.001 for both]). Conclusions: In patients with hypothyroidism, in addition to compromised LV diastolic function, LV longitudinal systolic function is also impaired compared to healthy subjects of the same age and gender. These findings suggest significant subendocardial function impairment, reflecting potentially micro-circulation disease that requires optimum management.

Evaluation of left atrial and ventricular myocardial functions by three-dimensional speckle tracking echocardiography in patients with euthyroid Hashimoto's thyroiditis

Hashimoto's Thyroiditis (HsT) is one of the most frequently occurring autoimmune diseases, characterized by lymphocytic infiltration, destruction and fibrosis of thyroid tissue and the presence of antibodies to thyroid peroxidase and thyroglobulin. The effects of euthyroid Hashimoto's thyroiditis (eHsT) on cardiovascular system are unclear. We aimed to identify if any deteriorations in LA and LV myocardial functions in patients with eHsT by 3D-STE in the current study. Fifty eight patients with eHsT and 60 age- and gender-matched controls were enrolled into the study. All participants underwent laboratory analyses which included thyroid hormones and thyroid autoantibody levels; and conventional 2D echocardiographic and 3D-STE analyses were performed. The mean age of the study patients was 34.5 ± 9 years, and 68.6% were female. Left ventricular global longitudinal strain (LV-GLS) was significantly depressed in the eHsT (+) group than in the control group (- 15.3 ± 3.6 vs. - 22.8 ± 3.8, p < 0.001). The LV-GLS was found to be disrupted linearly as thyroid autoantibodies increased (r = 0.684 for anti-TPO-ab and LV-GLS; r = 0.649 for anti-Tg-ab and LV-GLS). The present study demonstrated that 3D-STE is useful in the early detection of LV myocardial dysfunction in patients with eHsT. We found that eHsT had a negative effect on LV myocardial dynamics. According to these findings, these myocardial alterations that are present early in the disease process may be considered as a reason to start medical treatment earlier, even at the euthyroid stage to prevent LV myocardial impairment.

Subclinical hypothyroidism

Subclinical hypothyroidism (i.e. a condition characterized by serum TSH concentrations above the normal reference range in the presence of normal serum T4 levels) affects 4 to 20% of the population living in iodine-sufficient areas. The present work reviewed the clinical challenges regarding the signs and symptoms possibly related to subclinical hypothyroidism and the most recent guideline recommendations to treatment.

Cardiovascular risk factors in children and adolescents with subclinical hypothyroidism: A protocol for meta-analysis and systematic review

INTRODUCTION

Subclinical hypothyroidism (SH) is serum thyrotropin (TSH) slightly increased, while serum free thyroxine (FT4) levels are normal, and patients may have no abnormal symptoms, or only slight hypothyroidism, there are many studies proving that SH does increase cardiovascular risk in adults. However, there are few studies in children and adolescents. In order to explore whether children with subclinical hypothyroidism have a higher cardiovascular risk, we designed this meta-analysis.

METHODS

The protocol of this systematic review and meta-analysis was registered on the NPLASY (No. 202040182). The following electronic databases will be searched from the inception through the present to find studies that live up to our standard: PubMed, EMBASE, Web of Science, Cochrane Library, CNKI, Wanfang, and VIP. And we will include case-control studies, cohort studies, and cross-sectional studies. For including study, we will use the Newcastle-Ottawa Scale to evaluate their quality. Then 2 researchers will independently extract the required information. I statistics and subgroups will be used to analyze heterogeneity. We conduct a sensitivity analysis by excluding literature successively. When the system review contains >10 articles, Egger test will be conducted to evaluate publication bias.

RESULTS

From this study, we will assess the cardiovascular risk of children and adolescents with SH from multiple perspectives.

CONCLUSION

The conclusion of this paper will provide evidence for cardiovascular risk of SH children and provide basis for prevention and treatment of SH.

ETHICS AND DISSEMINATION

This meta-analysis does not collect personal primary data, so there is no need for formal moral recognition. The results of the system review will be presented to national and international conferences for publication.

Spontaneous closure of grade IV coronary perforation

Previous coronary artery bypass surgery (CABG) is an independent risk factor for coronary perforation (CP) during percutaneous coronary intervention (PCI) because of complexity of the cases. However in patients with prior CABG surgery, cardiac tamponade is rare because of local or regional pericardial adhesions.

Subclinical Hypothyroidism: A Review

IMPORTANCE

Subclinical hypothyroidism, defined as an elevated serum thyrotropin (often referred to as thyroid-stimulating hormone, or TSH) level with normal levels of free thyroxine (FT4) affects up to 10% of the adult population.

OBSERVATIONS

Subclinical hypothyroidism is most often caused by autoimmune (Hashimoto) thyroiditis. However, serum thyrotropin levels rise as people without thyroid disease age; serum thyrotropin concentrations may surpass the upper limit of the traditional reference range of 4 to 5 mU/L among elderly patients. This phenomenon has likely led to an overestimation of the true prevalence of subclinical hypothyroidism in persons older than 70 years. In patients who have circulating thyroid peroxidase antibodies, there is a greater risk of progression from subclinical to overt hypothyroidism. Subclinical hypothyroidism may be associated with an increased risk of heart failure, coronary artery disease events, and mortality from coronary heart disease. In addition, middle-aged patients with subclinical hypothyroidism may have cognitive impairment, nonspecific symptoms such as fatigue, and altered mood. In the absence of large randomized trials showing benefit from levothyroxine therapy, the rationale for treatment is based on the potential for decreasing the risk of adverse cardiovascular events and the possibility of preventing progression to overt hypothyroidism. However, levothyroxine therapy may be associated with iatrogenic thyrotoxicosis, especially in elderly patients, and there is no evidence that it is beneficial in persons aged 65 years or older.

CONCLUSIONS AND RELEVANCE

Subclinical hypothyroidism is common and most individuals can be observed without treatment. Treatment might be indicated for patients with subclinical hypothyroidism and serum thyrotropin levels of 10 mU/L or higher or for young and middle-aged individuals with subclinical hypothyroidism and symptoms consistent with mild hypothyroidism.

Hypothyroidism and related diseases: a methodological quality assessment of meta-analysis

OBJECTIVES

There is an increasing prevalence of hypothyroidism and there is a growing body of meta-analyses (MAs) on the association between hypothyroidism and other diseases. However, the methodological quality of the MAs significantly varies. Thus, this study aimed to evaluate and summarise data on the methodological quality of MAs on the associations between hypothyroidism and other diseases using the Assessment of Multiple Systematic Reviews (AMSTAR) scale, providing suggestions for clinical decision-making processes.

DESIGN

To assess the methodological quality of MAs using the AMSTAR scale.

DATA SOURCES

A systematic literature search was performed in PubMed, EMBASE, the Cochrane Library, web of science and Chinese Biomedicine Literature Database.

ELIGIBILITY CRITERIA

We included MAs that had assessed the association between hypothyroidism and other diseases in humans and that had full texts regardless of the publication status. No restriction applied on language or date.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened the titles and abstracts of all searched literature to acquire potentially eligible publications. The full texts of possible eligible publications were downloaded and assessed. Inconsistent comments were resolved through discussions with a third reviewer.

RESULTS

52 studies were included. The average AMSTAR score of the included articles was 8.6 (range: 5-10), and those of English and Chinese MAs were 8.8 and 7.0, respectively. A total of 52 MAs were evaluated, and 19 (36.5%) and 33 (63.5%) of these MAs were of moderate and high quality, respectively. None of the MAs were of low quality. Only two MAs had an a priori design. Items 3, 5 and 9 had the highest compliance (50/52, 96.2%), and aside from item 1, items 7 and 8 had the lowest compliance (33/52,63.5%). According to the results of these MAs, hypothyroidism was significantly associated with cardiovascular diseases, metabolic diseases, neuropsychiatric disorders, breast cancer and pregnancy outcome.

CONCLUSIONS

The methodological quality of the included MAs on the association between hypothyroidism and other diseases was moderate to high. MAs with high qualities confirmed that hypothyroidism was significantly associated with cardiovascular diseases, metabolic syndrome, preterm birth and neonatal outcomes. Consideration of scientific quality when formulating conclusions should be made explicit and more attention should be paid to improving the methodological quality of MAs, and increasing their applicability for clinical decision-making.

Perforation of a Saphenous Vein Graft Anastomosed at a Y-Configuration to the Left Internal Mammary Artery

Perforation of a saphenous vein graft (SVG) is a rare, yet dreadful complication during percutaneous coronary intervention (PCI). Perforation of a SVG arising at a Y-construction from the left internal mammary artery (LIMA) can be catastrophic since manipulations and material delivery through the single LIMA inflow can aggravate ischemia and accelerate hemodynamic collapse. Prior CABG and pericardial obliteration should not offer reassurance against tamponade, since coronary perforation in these patients may cause the development of loculated pericardial effusions, a complication associated with high mortality. Treating physicians must be alert for potential periprocedural pitfalls during PCI in post-CABG patients and these should be taken into consideration during interventional planning, procedure and follow-up.

Diffuse Myocardial Injuries are Present in Subclinical Hypothyroidism: A Clinical Study Using Myocardial T1-mapping Quantification

Subclinical hypothyroidism (SHT) is a common disorder that may represent early thyroid dysfunction and is related to adverse cardiovascular events. However, myocardial injuries induced by SHT are difficult to detect. Our previous study demonstrated that the cardiac magnetic resonance (CMR) myocardial longitudinal relaxation time (T1) mapping technique is a useful tool for assessing diffuse myocardial injuries in overt hypothyroidism patients. This study was designed to detect whether diffuse myocardial injuries were present in SHT by using the T1 mapping technique. We found that SHT participants had significantly increased native T1 values within four segments of the left ventricle (all p < 0.01), especially patients with thyroid-stimulating hormone (TSH) levels ≥10 µIU/mL, compared with those in the controls. In addition, the native T1 values were negatively correlated with free thyroxine (FT4) (r = −0.476, p = 0.003) and were positively correlated with TSH (r = 0.489, p = 0.002). Furthermore, left ventricular diastolic function estimated by the peak filling rate (PFR) was significantly lower in patients with TSH levels ≥10 µIU/mL than that in the controls (p < 0.05). In conclusion, diffuse myocardial injuries were present in SHT, and T1 mapping may be a useful tool for evaluating mild myocardial injuries in SHT at an early stage. Our study is the first to confirm myocardial injuries in SHT patients using T1 mapping.

Assessment of cardiac function in absence of congenital and acquired heart disease in patients with Down syndrome

BACKGROUND

Extra genetic material in patients with Down syndrome (DS) may affect the function of any organ system. We evaluated cardiac functions using conventional tissue Doppler and two-dimensional speckle tracking echocardiography in patients with DS in the absence of congenital and acquired heart disease in patients.

METHODS

A total of 115 patients with DS between 6 and 13 years of age with clinically and anatomically normal heart and 55 healthy children were included in this cross-sectional study. DS was diagnosed by a karyotype test. Patients with mosaic type were not included in this study. Systolic and diastolic functions were evaluated by echocardiography.

RESULTS

Pulsed waved Doppler transmitral early/late inflow velocity (E/A), tissue Doppler mitral annular early/late diastolic peak velocity (Ea/Aa), transtricuspid E/A and tricuspid valve annulus Ea/Aa, pulmonary venous Doppler systolic/diastolic (S/D) wave ratio were lower in patients with Down syndrome than in the control group (P=0.04, P=0.001, P<0.05, P<0.001, P<0.001, respectively). Mitral and tricuspid annular Ea were lower in patients with DS (P<0.001). The right and left ventricular myocardial performance indexes were higher in patients with DS than in the controls (P<0.01). They had significantly higher left ventricular mass, ejection fraction, the mitral annular plane systolic excursion values. However, the Down syndrome group compared with the controls had a lower strain values examined by two-dimensional longitudinal speckle-tracking strain echocardiography.

CONCLUSION

These findings suggest conventional tissue Doppler and two-dimensional longitudinal speckletracking strain echocardiography were useful methods of investigating ventricular function and identifying a higher incidence of biventricular dysfunction in patients with Down syndrome compared with the healthy controls.

Echocardiographic Evaluation of Biventricular Function in Patients with Euthyroid Hashimoto's Thyroiditis

OBJECTIVE

The aim of this study was to evaluate the left (LV) and right (RV) ventricular function in euthyroid Hashimoto's thyroiditis (eHT) patients.

SUBJECTS AND METHODS

Forty-five patients diagnosed with eHT and 45 age- and gender-matched control subjects were enrolled in this study. Echocardiographic parameters reflecting RV and LV functions such as chamber dimensions, ejection fraction, fractional shortening, conventional and tissue Doppler-derived early and late filling velocities (E, A, E', A'), isovolumic relaxation (IVRT) and contraction (IVCT) times, ejection time (ET), deceleration time (DT), Tei index, pulmonary acceleration time (PAcT) and tricuspid annular plane systolic excursion (TAPSE) of patients with eHT were compared to those of control subjects using the paired-samples t test or Wilcoxon signed-rank test.

RESULTS

Regarding the LV function, compared to the controls patients with eHT had a higher LV-Tei index (0.6 ± 0.2 vs. 0.4 ± 0.1, p < 0.001), higher DT (p < 0.001) and IVRT (p < 0.001) values, and higher E/E' ratios (p = 0.04). In contrast, the peak E wave velocity (p = 0.02), E/A ratio (p = 0.01) and ET (p = 0.02) were significantly lower in the eHT group than amongst the controls. The RV, Tei index (0.40 ± 0.11 vs. 0.28 ± 0.07, p < 0.001), TAPSE (2.0 ± 0.3 vs. 2.2 ± 0.2 mm, p < 0.001), PAcT (124.3 ± 22.6 vs. 149.4 ± 18.3 ms, p < 0.001), A' (p = 0.007) and IVCT (p = 0.001) were significantly higher in patients with eHT than the controls. However, the tricuspid E/A ratio (p = 0.01), E' (p = 0.03) and E'/A' ratio (p = 0.001) were significantly lower in the eHT patients than the control group.

CONCLUSIONS

This study demonstrated that both RV and LV functions were impaired in patients with eHT.

Coronary bypass graft perforation during percutaneous intervention

INTRODUCTION

Coronary artery bypass grafts are prone to accelerated atherosclerosis and as such graft stenosis is frequently encountered in clinical practice. Complications specific to graft- PCI include no-reflow, distal embolization, stent restenosis and thrombosis. Graft perforation during PCI is a rare coomplication of the procedure. Published literature on the predictors of perforation and management strategy remains limited to anecdotal cases.

METHOD

In this review we collected data on all cases of graft perforations reported in PubMed/Medline from 1987 to 2015.

RESULT

37 cases of graft perforation were reported. High risk grafts for perforations included, old grafts (14±7.8years) with more than 80% luminal stenosis. Perforations were noted after use of different cardiac devices and included stent placement (30%, N=11), balloon angioplasty (36%, N=14), post-dilation with non complaint balloon (16%, N=6), guide wire perforation (1 case), post IVUS imaging (1 case) and one case after use of thrombus extraction device. Average stent diameter of 3.7±0.7 mm, average balloon pressure of 15.5±5 atm and 3 or more balloon inflations commonly resulted in graft perforation. 78% of cases reported class III perforation. Covered stent implantation was strongly associated with controlling acute bleed after graft perforation than prolonged balloon inflation (p=0.0001). Majority of cases reported using covered stents (81%). Average stent diameter of 3.9±0.7mm, average stent length of 18.5±6mm and the average deployment pressure of 14±2atm were reported to be effective in controlling the bleed. 95% of the patients did well post procedure and with prolonged hospitalization (8±4days). 24% of cases reported cardiac tamponade causing hemodynamic compromise including 2 peri-procedural deaths.

CONCLUSION

Graft perforation can be effectively treated with covered stent grafts with good immediate results, short term outcome and acceptable peri-procedural risks.

Endothelial Functioning and Hemodynamic Parameters in Rats with Subclinical Hypothyroid and the Effects of Thyroxine Replacement

OBJECTIVE

Subclinical hypothyroidism (SCH) and its associations with atherosclerosis (AS) and cardiovascular disease remain controversial. The purpose of our study was to observe changes in endothelial functioning and hemodynamics in rats with SCH and to determine whether L-thyroxine (L-T4) administration affects these changes.

METHODS

In total, sixty male Wistar rats were randomly divided into the following three groups with 20 rats each: control euthyroid rats, SCH rats and SCH rats that had been treated with thyroxine (SCH+T4). The SCH rats were induced by administration of 10 mg x kg(-1) x d(-1) methimazole (MMI) once daily by gavage for 3 months. The SCH+T4 rats were administered the same dose of MMI for three months in addition to 2 μg x kg(-1) x d(-1) L-T4 once daily by gavage after 45 days of MMI administration. The control rats received physiological saline via gavage.

RESULTS

The SCH group had significantly higher thyroid-stimulating hormone (TSH), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and endothelin (ET) levels and a lower nitric oxide (NO) level than the control and SCH+T4 groups. The tail and carotid artery blood pressures, left ventricular systolic pressure, heart rate and aorta ventralis blood flow were significantly lower in the SCH group than in the control and SCH+T4 groups. ACH treatment caused concentration-dependent relaxation, which was reduced in the SCH arteries compared with the control and SCH+T4 arteries. Histopathological examination revealed the absence of pathological changes in the SCH rat arteries.

CONCLUSIONS

These findings demonstrate that L-T4 treatment ameliorates endothelial dysfunction and hemodynamic changes in SCH rats.

The effect of L-thyroxine treatment on left ventricular functions in children with subclinical hypothyroidism

OBJECTIVE

The aim of this study was to search for evidence suggesting treatment for childhood subclinical hypothyroidism (SH) by evaluating left ventricular (LV) functions of children with SH by using M-mode and tissue Doppler echocardiography (TDE).

METHODS

Children with SH and euthyroid healthy children (control group) were enrolled in the study. At baseline and 6 months after euthyroidism was achieved, M-mode and TDE were performed and LV functions were evaluated. Pretreatment parameters of the SH group were compared with those of controls and post-treatment parameters.

RESULTS

31 children with SH and 32 euthyroid healthy children were enrolled in the study. The groups had similar age, gender, puberty and body mass index. Interventricular septum thickness and LV mass index, which are the parameters for LV morphology, were slightly increased in the SH group than in the controls (p<0.05). In TDE, children with SH had significant changes in LV diastolic (lower E'm, higher E/E'm ratio and longer isovolumic relaxation time) and systolic functions (lower isovolumic contraction time) compared with controls (p<0.05). Six months after euthyroidism was achieved, TDE showed a significant improvement of some of the diastolic and systolic parameters (p<0.05).

CONCLUSIONS

The results of this study showed that SH is associated with subclinical alterations in LV function, and LT4 replacement may improve LV systolic and diastolic parameters. However, since SH is usually a self-limiting process, these improvements in LV functions may simply be associated with the natural course of the disease and/or physiological linear growth of the children.

The effect of L-thyroxine treatment on hypothyroid symptom scores and lipid profile in children with subclinical hypothyroidism

OBJECTIVE

To evaluate i) the frequency of typical hypothyroidism symptoms in children with subclinical hypothyroidism (SH), ii) to evaluate the association of SH with lipoproteins and iii) to investigate possible improving effects of L-thyroxine (LT4) treatment on these findings.

METHODS

Twenty-seven children with SH who had elevated thyroid-stimulating hormone (TSH: >4.94 µIU/L) but normal free T4 levels and healthy euthyroid children of similar age and sex were enrolled in the study. Anthropometric and laboratory (lipid profile and thyroid function tests) measurements were performed at diagnosis and six months after euthyroidism was achieved. All children were also subjected to a questionnaire on hypothyroid symptoms at diagnosis. The SH patients were subjected to the questionnaire also following treatment. Pre-treatment data were compared with those of controls and post-treatment measurements.

RESULTS

Anthropometric and laboratory parameters of the groups were not statistically different except for higher TSH levels in the SH group. Serum lipoprotein levels and dyslipidemia frequency were similar between the groups. Compared to the controls, hypothyroidism symptom score was significantly higher in the SH group. Six months after euthyroidism was achieved, a significant reduction in the hypothyroid symptom score was obtained in the SH group. Except for significantly higher serum TSH values, no significant differences regarding demographic characteristics, symptom scores and lipid parameters were present between patients with Hashimoto's thyroiditis and the remaining SH patients.

CONCLUSION

The results of this study showed that in children with SH i) the hypothyroidism symptom score was significantly higher than in euthyroid children, ii) LT4 treatment improved the hypothyroidism symptom score and iii) SH does not seem to be associated with dyslipidemia.

Subclinical hypothyroidism in childhood and adolescense

Subclinical hypothyroidism (SH) is defined as a serum thyroid-stimulating hormone (TSH) level above the reference range with normal serum free thyroxin (sT4) and free triiodothyronine (sT3) levels. The prevalence of SH in children and adolescents is reported between 1.7% and 9.5%. Hashimoto's thyroiditis is the most prevalent cause of SH in children. Although it has been suggested that SH is entirely an asymptomatic laboratory diagnosis, typical hypothyroid symptoms as well have been reported in some patients. Results of the adult studies on SH revealed that SH had unfavorable effects on cardiovascular system (atherosclerosis); metabolic parameters (dyslipidemia, insulin resistance, etc.); neuromuscular system; and cognitive functions in the long term. The number of studies investigating the effect of childhood SH on growth, bone maturation, lipid parameters, carbohydrate metabolism, neuromuscular system, and cognitive and cardiac function is limited. Knowledge about the natural history of SH is unclear even though there are numerous studies upon this subject. In children and adults, treatment of SH with L-T₄ is still a matter of debate, and there is no consensus on this issue yet.

Subclinical hypothyroidism and left ventricular mechanics: a three-dimensional speckle tracking study

CONTEXT

Subclinical hypothyroidism (SHT) is associated with left ventricular (LV) remodeling. The LV mechanics has not been previously assessed by two- and three-dimensional (2DE and 3DE) speckle tracking imaging in the SHT patients.

OBJECTIVES

The objective of the study was to investigate LV mechanics by 2DE and 3DE speckle tracking in the SHT patients and evaluate the influence of levothyroxine therapy on LV remodeling.

DESIGN

We conducted a prospective study. All SHT patients received levothyroxine therapy and were followed up for 1 year after the euthyroid state had been achieved.

SETTING

The study was performed at a university hospital.

PATIENTS

We included 54 untreated women with SHT and 40 healthy control women who were of similar age.

MAIN OUTCOME MEASURES

The 2DE strain and strain rates, 3DE volumes, 3DE strain, and thyroid hormones levels were assessed.

RESULTS

The 2DE LV longitudinal and circumferential strain and systolic and early diastolic strain rates were significantly decreased in the SHT patients before therapy in comparison with the controls or the SHT patients after therapy. The 3DE LV cardiac output and ejection fraction were significantly reduced in the SHT patients at baseline compared with the controls or patients after 1 year of treatment. The 3DE LV longitudinal and radial strains were significantly lower in the SHT group before treatment in comparison with the controls or patients after therapy, whereas the 3DE LV circumferential and area strains gradually increased from untreated SHT patients, among the treated SHT patients, to the controls.

CONCLUSION

SHT significantly affects LV deformation assessed by 2DE and 3DE speckle tracking. The improvement of LV mechanics after 1 year of levothyroxine treatment is significant but incomplete.

Left and right ventricular structure and function in subclinical hypothyroidism: the effects of one-year levothyroxine treatment

BACKGROUND

The aim of this study was to investigate left ventricular (LV) and right ventricular (RV) structure, function, and mechanics in patients with subclinical hypothyroidism (SHT), and to evaluate the effect of a 1-year levothyroxine treatment.

MATERIAL AND METHODS

We compared 45 untreated women with subclinical hypothyroidism and 35 healthy control women matched by age. All the subjects underwent laboratory analyses, which included a thyroid hormone levels (free T3, free T4, and TSH) test, and a complete 2-dimensional echocardiographic study. All the SHT patients received levothyroxine therapy and were followed for a year after euthyroid state was achieved.

RESULTS

The LV mass index in the SHT participants before and after replacement therapy was significantly higher than in controls. In the SHT patients before the treatment, LV diastolic function and global function estimated by the Tei index were significantly impaired, whereas the LV systolic function was decreased. The results show that LV mechanics was significantly impaired in the SHT patients at baseline. Additionally, the SHT participants before levothyroxine substitution had increased RV wall thickness and significantly impaired RV diastolic and global function in comparison with the controls or the SHT subjects after the treatment. Furthermore, RV mechanics was also significantly deteriorated in the SHT patients before the treatment.

CONCLUSIONS

Subclinical hypothyroidism significantly affected LV and RV structure, systolic, diastolic and global function, and LV and RV mechanics. Levothyroxine replacement therapy significantly improved cardiac structure, function, and mechanics in the SHT patients.

Polyunsaturated fatty acids for the prevention of atrial fibrillation after cardiac surgery: an updated meta-analysis of randomized controlled trials

BACKGROUND

Several clinical trials showed inconsistent results of the effect of polyunsaturated fatty acids (PUFA) on the incidence of post-operative atrial fibrillation (POAF). The aim of this meta-analysis is to investigate the effect of PUFA on the incidence of POAF in patients undergoing cardiac surgery.

METHODS AND RESULTS

PUBMED, EMBASE, Cochrane Library, and Google Scholar databases were searched for randomized controlled trials. Statistical heterogeneity was assessed using I(2) statistic and Cochran's Q statistic. The effect of PUFA on the incidence of POAF was presented as risk ratio (RR) with 95% confidence intervals (CIs) using a fixed effect model or random effect model depending on statistical heterogeneity. Subgroup analyses were conducted based on the baseline characteristics of patients, types of surgery, the ratio of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA), and the quality of the studies. Eight trials with 2687 patients were included in the analysis. Treatment with PUFA had no effect on the incidence of POAF in patients undergoing cardiac surgery compared to placebo [RR 0.86; 95% CI 0.71-1.04, p=0.110]. Subgroup analyses showed the quality of the studies, the ratio of EPA/DHA, accompanied with diabetes might impact the effect of PUFA on POAF. No evidence of publication bias was detected.

CONCLUSIONS

The present analysis suggests that treatment with PUFA preoperatively has no effect on the incidence of POAF in patients undergoing open heart surgery. However, patients with diabetes might get benefits from the treatment with PUFA preoperatively.