Impact of subclinical hypothyroidism on clinical outcomes following percutaneous coronary intervention

Impact of subclinical hypothyroidism on in-hospital outcomes and long-term mortality among acute myocardial infarction patients with diabetic mellitus

BACKGROUND

Thyroid-stimulating hormone (TSH) has been regarded as a predictor of poor outcomes in patients with acute myocardial infarction (AMI). AMI complicated by diabetes mellitus (DM) tends to have a high prevalence and a worse prognosis. We aim to evaluate the association between thyroid dysfunction and in-hospital outcomes and short- and medium-term mortality in diabetic patients with AMI.

METHODS

From January 2017 to November 2020, a total of 432 patients with AMI were included in this study, including 209 DM patients and 223 non-DM patients. Baseline characteristics, medical history, and laboratory parameters of patients were recorded after admission. In-hospital outcomes and 30-day mortality were recorded, and long-term mortality was recorded with a median follow-up of 34.2 ± 5.6 months.

RESULTS

Subclinical hypothyroidism (SCH) was defined as an elevated TSH level of more than with a normal range of circulating thyroid hormones. In AMI with DM group, 26/209 (12.4%) patients were complicated with SCH, these patients tend to be older and experienced worse in-hospital outcomes compared to patients without SCH, including higher rates of acute heart failure, acute kidney injury, and atrial fibrillation. Moreover, patients with SCH had a higher prevalence of 30-day mortality and long-term mortality, compared with patients without SCH.

CONCLUSIONS

Diabetic AMI patients with SCH had worse in-hospital outcomes and higher 30-day and long-term mortality. Patients with diabetic AMI should pay attention to thyroid function, and SCH is an independent risk factor for short-term and long-term mortality in diabetic AMI patients.

Analysis of Subclinical Thyroid Dysfunction and Metabolic Abnormality in 28568 Healthy People

We analyzed the detection rates of metabolic syndrome (MetS) and subclinical thyroid dysfunction, including subclinical hyperthyroidism (SCHyper) and subclinical hypothyroidism (SCH), in healthy people, as well as their relationship. Clinical data were collected from 28,568 healthy individuals who underwent physical examinations. The detection rates of SCHyper, SCH, and MetS, as well as in different genders and ages, were analyzed. The detection rate of SCHyper and SCH in females was significantly higher than that in males (P < 0.001), but that of MetS in males was significantly higher than that in females (P < 0.001). In each age group, the detection rate of SCH in females was higher than that in males (P < 0.001). The detection rate of SCH was significantly different in different age groups (P < 0.001). The detection rates of hyperlipidemia (P < 0.001), obesity (P = 0.004), hypertension (P = 0.009), and hyperglycemia (P < 0.001) in the female SCH group were significantly higher than those in the normal group. The detection rates of hyperlipidemia (P = 0.006), obesity (P = 0.04), and hypertension (P = 0.04) in the male SCH group were higher than those in the normal group. The males with SCHyper were more prone to hyperlipidemia (P = 0.02) and obesity (P = 0.03). In addition, the female SCHyper group was not significantly different from the normal group (P > 0.05). Conclusively, the detection rate of SCHyper and SCH in females is higher than that in males, which increases with age. Attention should be paid to subclinical thyroid dysfunction in elderly people, especially females. Early individualized screening and early intervention should be carried out for people with abnormal metabolism.

Subclinical Hypothyroidism and Clinical Outcomes After Percutaneous Coronary Intervention: A Meta-Analysis

While subclinical hypothyroidism (SCH) was reportedly associated with an increased risk of cardiovascular mortality, the relationship between SCH and clinical outcomes of patients undergoing percutaneous coronary intervention (PCI) is uncertain. The aim of this study was to assess the association of SCH and cardiovascular outcomes in patients undergoing PCI. We searched PubMed, Embase, Scopus, and CENTRAL databases from its inception until April 1, 2022 for studies comparing the outcomes between SCH and euthyroid patients undergoing PCI. Outcomes of interest include cardiovascular mortality, all-cause mortality, myocardial infarction (MI), major adverse cardiovascular and cerebrovascular events (MACCE), repeat revascularization and heart failure. Outcomes were pooled using the DerSimonian and Laird random-effects model and reported as risk ratios (RR) and 95% confidence intervals (CI). A total of 7 studies involving 1132 patients with SCH and 11,753 euthyroid patients were included in the analysis. Compared with euthyroid patients, patients with SCH had significantly higher risk of cardiovascular mortality (RR 2.16, 95% CI: 1.38-3.38, P < 0.001), all-cause mortality (RR 1.68, 95% CI: 1.23-2.29, P = 0.001) and repeat revascularization (RR 1.96, 95% CI: 1.08-3.58, P = 0.03). However, there were no differences between both groups in terms of incidence of MI (RR 1.81, 95% CI: 0.97-3.37, P = 0.06), MACCE (RR 2.24, 95% CI: 0.55-9.08, P = 0.26) and heart failure (RR 5.38, 95% CI: 0.28-102.35, P = 0.26). Our analysis suggests among patients undergoing PCI, SCH was associated with increased risk of cardiovascular mortality, all-cause mortality and repeat revascularization compared to euthyroid patients.

Thyroid Hormone and Heart Failure: Charting Known Pathways for Cardiac Repair/Regeneration

Heart failure affects more than 64 million people worldwide, having a serious impact on their survival and quality of life. Exploring its pathophysiology and molecular bases is an urgent need in order to develop new therapeutic approaches. Thyroid hormone signaling, evolutionarily conserved, controls fundamental biological processes and has a crucial role in development and metabolism. Its active form is L-triiodothyronine, which not only regulates important gene expression by binding to its nuclear receptors, but also has nongenomic actions, controlling crucial intracellular signalings. Stressful stimuli, such as acute myocardial infarction, lead to changes in thyroid hormone signaling, and especially in the relation of the thyroid hormone and its nuclear receptor, which are associated with the reactivation of fetal development programmes, with structural remodeling and phenotypical changes in the cardiomyocytes. The recapitulation of fetal-like features of the signaling may be partially an incomplete effort of the myocardium to recapitulate its developmental program and enable cardiomyocytes to proliferate and finally to regenerate. In this review, we will discuss the experimental and clinical evidence about the role of the thyroid hormone in the recovery of the myocardium in the setting of heart failure with reduced and preserved ejection fraction and its future therapeutic implications.

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.

Hypothyroidism predicts worsened prognosis in patients undergoing percutaneous coronary intervention

Background

The link between thyroid dysfunction and cardiovascular disease is well established. Hypothyroidism has been significantly associated with increased risk of dyslipidemia, atherosclerosis and heart failure. However, little is known regarding its effect on patients undergoing percutaneous coronary intervention (PCI).

Aim

The aim of study was to examine the impact of concomitant hypothyroidism on mortality and major adverse cardiac event (MACE) in patients undergoing PCI.

Methods

The Rabin Medical Center PCI registry includes all consecutive patients who have undergone PCI between 2004 and 2020. We identified patients with prior diagnosis of hypothyroidism, and compared rates of mortality and MACE (comprising death, myocardial infarction, target vessel revascularization and/or coronary bypass surgery).

Results

Among 28,274 patients, 1,922 (6.8%) were found to have hypothryoidism. These patients were older (70.3 ± 10.4 vs. 66.0 ± 11.8 y.o, P &lt; 0.001) and more likely to be women (34.2% vs. 26.1%, P &lt; 0.001). They had a higher prevalence of atrial fibrillation (10.8% vs. 7.7%, P &lt; 0.001), chronic renal dysfunction (25.1% vs. 18.7%, P = 0.04) and dementia (2.9% vs. 1.8%, P = 0.004). PCI was performed on ACS setting in 52–54% of patients in both groups (p = 0.569). Unadjusted 5-year rates of all-cause mortality (26.9% vs. 20.3%, P &lt; 0.001) and MACE (40.3% vs. 29.4%, P &lt; 0.001) were higher for hypothyroid patients. A propensity match score was able to form 672 matched pairs of HT and control patients, showing similar results. Moreover, following multivariate analysis, TSH as a continuous parameter was associated with a higher risk of mortality and MACE (HR, 1.06 per additional 1 mIU/L; CI, 1.02–1.11; P &lt; 0.001 and HR, 1.07; CI, 1.02–1.12; P &lt; 0.001, respectively) at 5-year follow up.

Conclusion

In our study, hypothyroidism confers worse outcomes in patients undergoing PCI. Further research is needed to establish effective ways to mitigate this augmented risk.

Influence of Mild Thyroid Dysfunction on Outcomes after Off-Pump Coronary Artery Bypass Surgery

We retrospectively evaluated the association between preoperative mild thyroid dysfunction (subclinical hypothyroidism [SCH] or low triiodothyronine [T3] syndrome) and outcomes in patients who underwent off-pump coronary surgery (OPCAB). Further, 800 patients (2015−2020) were divided into euthyroid, low T3, and SCH groups. The primary outcome assessed the association with composite endpoints (myocardial infarction, prolonged mechanical ventilation [>24 h], acute kidney injury, and 30-day/in-hospital mortality). The secondary outcome assessed the association with long-term mortality and 10% and 8% of the patients exhibited low T3 and SCH, respectively. Incidences of composite endpoints were significantly higher in the low T3 and SCH groups versus the euthyroid group (50.6%, 45.2%, 17.4%, respectively, p < 0.001). Multivariable regression analysis revealed chronic kidney disease, anemia, EuroSCORE, low T3, and SCH as independent risk factors of composite endpoints. The long-term mortality rate (median follow-up, 30 months) was higher in the low T3 and SCH groups than in the euthyroid group (9.6%, 11.3%, 2.4%, respectively, p < 0.001). In the absence of overt thyroid dysfunction, low T3 and SCH were associated with increased risk of adverse outcomes after OPCAB. Moreover, the adverse influences of low T3 and SCH seem to extend to long-term mortality, implying that routine thyroid function tests may enhance accurate risk stratification.

Impact of persistent subclinical hypothyroidism on clinical outcomes in non-ST-segment elevation acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND

Data on the association of subclinical hypothyroidism (SCH) with the severity of coronary artery disease and major adverse cardiovascular and cerebral events (MACCE) in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) after percutaneous coronary intervention (PCI) are limited and conflicting.

OBJECTIVE

We established the baseline rate of SCH and followed the trajectory of thyroid-stimulating hormone (TSH) values during and after hospitalisation for PCI for up to six months and determined whether persistent SCH was associated with the severity of coronary artery disease and MACCE in patients with NSTE-ACS after PCI.

DESIGN

Population-based prospective cohort study.

PATIENTS

We included patients with NSTE-ACS who underwent PCI with simple balloon angioplasty or stent implantation for coronary heart disease.

MEASUREMENTS

Thyroid function tests of patients before PCI and 1 day, 1 week, 1 and 6 months after PCI were performed. Cases showing transient SCH were excluded. Patients were divided into two groups based on the results of four TSH tests: 0.27-4.2 mIU/L (n = 1472, 89.7%) and >4.2 mIU/L (n = 170, 10.4%). The risk factors for the severity of coronary artery lesions were estimated using multinomial logistic regression analysis. Univariate and multivariate Cox regression analyses were used to study the relationship between TSH and MACCE.

RESULTS

Among 1642 patients, there were 1070 males (65.2%) and 572 females (34.8%), with an average age of 62.5 ± 9.6 years. SCH patients had a wider range of diseased vessels and a higher number of diseased vessels (p < .05). TSH level was an independent risk factor for moderate [odds ratio (OR) = 1.144, 95% confidence interval (95% CI): 1.057-1.237, p = .001] and severe (OR = 1.131, 95% CI: 1.043-1.226, p = .003) coronary artery lesions. After adjusting for covariates, the risk of MACCE [hazard ratio (HR): 4.067, p < .001], nonfatal myocardial infarction (HR: 14.724, p = .003), and unplanned PCI (HR: 5.028, p < .001) were higher in the SCH group than in the euthyroidism group. There were no significant differences in the incidence of heart failure (HR: 6.012, p = .175), nonfatal stroke (HR: 2.039, p = .302), unplanned coronary artery bypass grafting (CABG) (HR: 1.541, p = .57), or cardiac death (HR: 2.704, p = .375) between the two groups.

CONCLUSIONS

Preoperative TSH levels and changes in thyroid hormone levels several months post-PCI in NSTE-ACS patients are highly significant in practice. Persistent SCH is associated with severe coronary artery lesions and MACCE, and may be a predictor for evaluating the prognosis of PCI-treated NSTE-ACS patients.

Association of Mild Thyroid Dysfunction and Adverse Prognosis Among Chinese Patients With Acute ST Segment Elevation Myocardial Infarction

AIMS

Thyroid hormones widely affect the cardiovascular system, but the effects of mild thyroid dysfunction on the clinical prognosis of patients with acute ST segment elevation myocardial infarction (STEMI) remains unclear. Our aims were to analyze the relations between mild thyroid dysfunction at admission and clinical outcomes in Chinese patients with STEMI.

METHODS

A total of 1,176 STEMI patients with the available data of thyroid function and follow-up were analyzed, including 348 patients with mild thyroid dysfunction [subclinical hypothyroidism (n=81), hyperthyroidism (SHyper) (n=51), and low triiodothyronine syndrome (LT3S) (n=216)] and 828 patients with euthyroid function. During a median 4.4-year follow-up, in-hospital mortality, cardiac and all-cause mortalities were subsequently compared among the four groups.

RESULTS

Compared with the euthyroid group, STEMI patients in the SHyper and LT3S groups faced obviously increased risks of in-hospital death [odds ratio (OR): 5.007, 95% confidence interval (CI): 1.246-20.124, p = 0.023 and OR: 2.491, 95% CI: 1.054-5.887, p = 0.037, respectively) even after adjustment for various confounding factors. During a median 4.4-year follow-up, STEMI patients with LT3S at baseline had higher cardiovascular mortality [hazard ratio (HR): 1.880, 95% CI: 1.178-2.998, p = 0.008] and all-cause mortality HR: 1.647, 95% CI: 1.072-2.531, p = 0.023] than those with euthyroid at baseline, whereas no significantly increased mortality was found for STEMI patients with SCH and SHyper at baseline.

CONCLUSIONS

STEMI patients with SHyper at admission had increased risk of in-hospital mortality, and STEMI patients with LT3S at baseline had worse prognosis and higher incidences of in-hospital mortality and cardiovascular and all-cause deaths compared with euthyroid patients.

The impact of subclinical hypothyroidism on long-term outcomes in older patients undergoing percutaneous coronary intervention

BACKGROUND

Subclinical hypothyroidism (SCH) is reportedly associated with an increased risk of adverse events in patients undergoing percutaneous coronary intervention (PCI). The prognostic significance of SCH in the elderly was poorly defined. The purpose of this study was to evaluate the association between SCH and long-term outcomes in older patients undergoing PCI.

METHODS

Three thousand one hundred sixty-eight patients aged 65 years or older who underwent PCI from January 2012 to October 2014 were included. Patients were divided into SCH group (n = 320) and euthyroidism (ET) group (n = 2848) based on thyroid function test. Cox proportional hazard regression analyses were used to estimate the relative risks (RRs) of all-cause death and cardiac death for patients with SCH during a 4-year follow-up period.

RESULTS

There were 227 deaths during the follow-up period including 124 deaths caused by cardiac events. There was no significant difference in mortality rate between the SCH group and the ET group (p > 0.05). After adjustment for covariates, compared with patients with ET, the RRs of death from all-cause and cardiac in patients with SCH were 1.261 (95%CI: 0.802-1.982, p = 0.315) and 1.231 (95%CI: 0.650-2.334, p = 0.524), respectively. When SCH was stratified by age, gender, and degree of thyroid-stimulating hormone elevation, no significant associations were also found in any stratum.

CONCLUSION

Our investigation revealed that SCH was negatively associated with the outcome of PCI in older patients.

Unknown Subclinical Hypothyroidism and In-Hospital Outcomes and Short- and Long-Term All-Cause Mortality among ST Segment Elevation Myocardial Infarction Patients Undergoing Percutaneous Coronary Intervention

Subclinical hypothyroidism (SCH) is defined as an elevated serum thyroid-stimulating hormone (TSH) level with a normal serum-free thyroxine (FT4) level. SCH has been associated with an increased risk of adverse cardiovascular outcomes. We investigated possible associations of unknown SCH with in-hospital outcomes and short- and long-term all-cause mortality in a large cohort of patients with ST segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI). This retrospective, single-center observational study evaluated the TSH and FT4 levels of 1593 STEMI patients with no known history of hypothyroidism or thyroid replacement treatment who were admitted to the coronary care unit and underwent PCI between 1/2008 and 8/2017. SCH was defined as TSH levels ≥ 5 mU/mL in the presence of normal FT4 levels. Unknown SCH was detected in 68/1593 (4.2%) STEMI patients. These patients had significantly worse in-hospital outcomes compared to patients without SCH, including higher rates of acute kidney injury (p = 0.003) and left ventricular ejection fraction ≤ 40% (p = 0.03). Moreover, 30-day mortality (p = 0.02) and long-term (mean 4.2 ± 2.3 years) mortality (p = 0.007) were also significantly higher in patients with SCH. The thyroid function of STEMI patients should be routinely tested before they undergo a planned PCI procedure.

Nonthyroidal Illness Syndrome and Hypothyroidism in Ischemic Heart Disease Population: A Systematic Review and Meta-Analysis

CONTEXT

The association of non-thyroidal illness syndrome (NTIS) and hypothyroidism with the prognosis in ischemic heart disease (IHD) population is inconclusive.

OBJECTIVE

We aimed to evaluate the influence of NTIS and hypothyroidism on all-cause mortality and major adverse cardiac events (MACE) in IHD population.

DATA SOURCES

We searched PubMed, EMBASE, Scopus, Web of Science, and Cochrane Library from inception through February 17, 2020.

STUDY SELECTION

Original articles enrolling IHD patients, comparing all-cause mortality and MACE of NTIS and hypothyroidism with those of euthyroidism, and providing sufficient information for meta-analysis were considered eligible.

DATA EXTRACTION

Relevant information and numerical data were extracted for methodological assessment and meta-analysis.

DATA SYNTHESIS

Twenty-three studies were included. The IHD population with NTIS was associated with higher risk of all-cause mortality (hazard ratio [HR] = 2.61; 95% confidence interval [CI] = 1.89-3.59) and MACE (HR = 2.22; 95% CI = 1.71-2.89) than that without. In addition, the IHD population with hypothyroidism was also associated with higher risk of all-cause mortality (HR = 1.47; 95% CI = 1.10-1.97) and MACE (HR = 1.53; 95% CI = 1.19-1.97) than that without. In the subgroup analysis, the acute coronary syndrome (ACS) subpopulation with NTIS was associated with higher risk of all-cause mortality (HR = 3.30; 95% CI = 2.43-4.48) and MACE (HR = 2.19; 95% CI = 1.45-3.30). The ACS subpopulation with hypothyroidism was also associated with higher risk of all-cause mortality (HR = 1.67; 95% CI = 1.17-2.39).

CONCLUSIONS

The IHD population with concomitant NTIS or hypothyroidism was associated with higher risk of all-cause mortality and MACE. Future research is required to provide evidence of the causal relationship and to elucidate whether normalizing thyroid function parameters can improve prognosis.

Effect of Levothyroxine on Left Ventricular Ejection Fraction in Patients With Subclinical Hypothyroidism and Acute Myocardial Infarction: A Randomized Clinical Trial

IMPORTANCE

Thyroid hormones play a key role in modulating myocardial contractility. Subclinical hypothyroidism in patients with acute myocardial infarction is associated with poor prognosis.

OBJECTIVE

To evaluate the effect of levothyroxine treatment on left ventricular function in patients with acute myocardial infarction and subclinical hypothyroidism.

DESIGN, SETTING, AND PARTICIPANTS

A double-blind, randomized clinical trial conducted in 6 hospitals in the United Kingdom. Patients with acute myocardial infarction including ST-segment elevation and non-ST-segment elevation were recruited between February 2015 and December 2016, with the last participant being followed up in December 2017.

INTERVENTIONS

Levothyroxine treatment (n = 46) commencing at 25 µg titrated to aim for serum thyrotropin levels between 0.4 and 2.5 mU/L or identical placebo (n = 49), both provided in capsule form, once daily for 52 weeks.

MAIN OUTCOMES AND MEASURES

The primary outcome measure was left ventricular ejection fraction at 52 weeks, assessed by magnetic resonance imaging, adjusted for age, sex, type of acute myocardial infarction, affected coronary artery territory, and baseline left ventricular ejection fraction. Secondary measures were left ventricular volumes, infarct size (assessed in a subgroup [n = 60]), adverse events, and patient-reported outcome measures of health status, health-related quality of life, and depression.

RESULTS

Among the 95 participants randomized, the mean (SD) age was 63.5 (9.5) years, 72 (76.6%) were men, and 65 (69.1%) had ST-segment elevation myocardial infarction. The median serum thyrotropin level was 5.7 mU/L (interquartile range, 4.8-7.3 mU/L) and the mean (SD) free thyroxine level was 1.14 (0.16) ng/dL. The primary outcome measurements at 52 weeks were available in 85 patients (89.5%). The mean left ventricular ejection fraction at baseline and at 52 weeks was 51.3% and 53.8%, respectively, in the levothyroxine group compared with 54.0% and 56.1%, respectively, in the placebo group (adjusted difference in groups, 0.76% [95% CI, -0.93% to 2.46%]; P = .37). None of the 6 secondary outcomes showed a significant difference between the levothyroxine and placebo treatment groups. There were 15 (33.3%) and 18 (36.7%) cardiovascular adverse events in the levothyroxine and placebo groups, respectively.

CONCLUSIONS AND RELEVANCE

In this preliminary study involving patients with subclinical hypothyroidism and acute myocardial infarction, treatment with levothyroxine, compared with placebo, did not significantly improve left ventricular ejection fraction after 52 weeks. These findings do not support treatment of subclinical hypothyroidism in patients with acute myocardial infarction.

TRIAL REGISTRATION

isrctn.org Identifier: http://www.isrctn.com/ISRCTN52505169.

Thyroid Hormone Signalling: From the Dawn of Life to the Bedside

Thyroid hormone (TH) signalling is a key modulator of fundamental biological processes that has been evolutionarily conserved in both vertebrate and invertebrate species. TH may have initially emerged as a nutrient signal to convey environmental information to organisms to induce morpho-anatomical changes that could maximise the exploitation of environmental resources, and eventually integrated into the machinery of gene regulation and energy production to become a key regulator of development and metabolism. As such, TH signalling is particularly sensitive to environmental stimuli, and its alterations result in fundamental changes in homeostasis and physiology. Stressful stimuli of various origins lead to changes in the TH-TH receptor (TR) axis in different adult mammalian organs that are associated with phenotypical changes in terminally differentiated cells, the reactivation of foetal development programmes, structural remodelling and pathological growth. Here, we discuss the evolution of TH signalling, review evolutionarily conserved functions of THs in essential biological processes, such as metamorphosis and perinatal development, and analyse the role of TH signalling in the phenotypical and morphological changes that occur after injury, repair and regeneration in adult mammalian organs. Finally, we examine the potential of TH treatment as a therapeutic strategy for improving organ structure and functions following injury.

Thyroid stimulating hormone elevation as a predictor of long-term mortality in patients with acute myocardial infarction

BACKGROUND

Hypothyroidism has been known to be associated with hyperlipidemia, endothelial dysfunction and atherosclerosis. Elevation of thyroid-stimulation hormone (TSH) is a gold standard to detect these conditions. However, no large studies have investigated the association between TSH elevation and long-term clinical outcomes in patients with acute myocardial infarction (AMI).

HYPOTHESIS

Hypothyroidism is associated with higher mortality in patients with AMI.

METHODS

A total of 4748 AMI patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents were consecutively enrolled. We analyzed 1977 patients whose thyroid function data available after the exclusion of hyperthyroidism and possible central hypothyroidism. Patients were divided into two groups; euthyroid group (n = 1846) with normal TSH and normal free thyroxine (FT4); hypothyroidism group (n = 131) with elevated TSH and normal or low FT4. The two groups were subsequently compared with their all-cause and cardiac mortalities.

RESULTS

Median follow-up duration was 3.5 years. Hypothyroidism group were older, included in more females, and had higher incidences of atrial fibrillation, stroke, and renal dysfunction. Elevated TSH was associated with significantly higher all-cause mortality (26.0% vs 11.7%, P < 0.0001) and cardiac mortality (9.2% vs 4.6%, P = 0.014). The multivariate Cox proportional hazards model identified that TSH elevation was a significant predictor of all-cause mortality (adjusted hazard ratio 1.560, 95% confidence interval 1.017 to 2.392, P = 0.041).

CONCLUSIONS

Our data suggest that AMI patients with TSH elevation had worse clinical outcome. Moreover, TSH elevation was a predictor of all-cause mortality in patients with AMI.

Thyroid hormone receptor α1 as a novel therapeutic target for tissue repair

Analogies between the damaged tissue and developing organ indicate that a regulatory network that drives embryonic organ development may control aspects of tissue repair. In this regard, there is a growing body of experimental and clinical evidence showing that TH may be critical for recovery after injury. Especially TRα1 has been reported to play an essential role in cell proliferation and differentiation and thus in the process of repair/regeneration in the heart and other tissues. Patients after myocardial infarction, stroke or therapeutic interventions [such as PCI for coronary artery disease (CAD)] with lower TH levels appear to have increased morbidity and mortality. Accordingly, TH treatment in clinical settings of ischemia/reperfusion such as by-pass surgery seems to be cardioprotective against ischemic injury. Furthermore, TH therapy of donors is shown to result in organ preservation and increased numbers of donors and improved post-transplantation graft survival. TH and thyroid analogs may prove novel therapeutic agents for tissue repair.

Impact of Hypothyroidism on Outcomes of Percutaneous Coronary Intervention with Coronary Atherectomy for Calcified Coronary Lesions: A Propensity-matched Analysis

Overt and subclinical hypothyroid states have been depicted as risk factors for a more prominent level of coronary calcification. The utilization of coronary atherectomy with percutaneous coronary intervention (PCI) is on the ascent over the past few years as lesions that are more complex are now attempted with a percutaneous approach. However, the real-world data on hypothyroid status influencing PCI with coronary atherectomy outcomes is very limited. Therefore, we proposed to investigate the outcomes of percutaneous coronary intervention with coronary atherectomy in hypothyroid patients using the largest inpatient database in the United States (US), the National Inpatient Sample (NIS). To minimize the selection bias, we surveyed and compared the outcomes in both the unmatched and propensity-score matched euthyroid and hypothyroid cohorts. Concisely, this propensity-matched analysis, using the largest population-based sample in the US, has established higher cardiovascular comorbidities and worse clinical outcomes of PCI with coronary atherectomy owing to clinical hypothyroidism.

Data on the impact of subclinical hypothyroidism on clinical outcomes following percutaneous coronary intervention

This article contains the data showing the different influence of subclinical hypothyroidism (SCH) on the risk of cardiovascular events after percutaneous coronary intervention (PCI) in various subgroups regarding myocardial infarction, previous PCI, the stent generation, total stent length, the extent of coronary artery disease, diabetes mellitus, obesity, a lipid reduction level and a C-reactive protein level. This article also contains the data showing the association between SCH and the risk of receiving repeat PCI for in-stent restenosis or de novo coronary stenosis. The data are supplemental to our original research article titled “Impact of Subclinical Hypothyroidism on Clinical Outcomes Following Percutaneous Coronary Intervention” (Lee et al., 2017) [1].