Evaluation of the Cardiac Morphologic Alterations Secondary to Autoimmune Thyroid Disorder Using Cardiac Magnetic Resonance Imaging

Evaluation of MRI-based radiomic features in heart morphologic variations as a consequence of autoimmune thyroid disorders

Radiomics (RC) was initially developed using computed tomography (CT) for oncological imaging. However, it can be applied to various scientific and clinical radiology fields regardless of the modalities involved. The purpose of this survey was to evaluate alterations in magnetic resonance imaging of the heart (CMR) in patients suffering from autoimmune thyroid disorders (AITD) by applying RC tools and mapping features. A total of 50 individuals were evaluated in this study. We searched for CMR examinations performed in our department between January 2019 and 2021 in patients with AITD. Thirty patients with AITD (21 men and 9 women, aged 51 to 78 years; mean age, 60 years) were enrolled in our survey. We enrolled a control group (CG) of 20 individuals (14 men and 6 women aged 53-87 years; mean age, 68 years) without AITD or cardiac disorders. Global native T1 and T2 mapping revealed no significant differences between groups. However, we identified significantly higher values of several texture parameters, including the gray-level co-occurrence matrix (GLCM) entropy, gray-level run-length matrix (GLRLM; short-run high gray-level emphasis (SRHGE), GLCM (Energy), gray-level size zone matrix length matrix (GLZLM; LZLGE), GLZLM (SZLGE), DISCRETIZED (HISTO-Energy) GLCM (Dissimilarity), and GLCM (Contrast), in patients with AITD in comparison to the CG (P < .01). Our results indicate that several RC properties extracted from CMR images can be used to discriminate between the AITD and CG groups.

Calculation of left ventricular volumes and systolic indices in monitoring the therapeutic effect of levothyroxine replacement therapy in subclinical hypothyroidism

BACKGROUND/AIM

Subclinical hypothyroidism (SCH) is defined as high thyroid-stimulating hormone (TSH) and normal thyroxine (T4) levels. Data on the effects of early substitution with levothyroxine on psychophysical health in SCH are not consistent enough to support its general administration. The aim of this study was to examine the effect of 3-months levothyroxine (LT4) treatment on cardiovascular function in symptomatic SCH with TSH <10 mIU/L.

METHODS

Anthropometric, biochemical, electro- and echocardiographic indices were measured in 35 patients with persistent symptomatic SCH (4 mIU/L < TSH <10 mIU/L; mean ± SD: 7.0 ± 2.1 mIU/L) and 40 healthy controls at baseline and three months after the euthyroid state had been achieved on LT4 for SCH group, or 3 months of follow-up for controls.

RESULTS

The analyses showed a significant reduction in body weight (P = .030), systolic and diastolic blood pressure (P = .024, P = .019), TSH (P < .001) and thyroid peroxidase antibodies (TPO Ab) (P < .001) on LT4 in the SCH group. There was a statistically significant decrease in end-systolic (ESV) and end-diastolic volumes (EDV) (P < .001, P < .001, respectively) after LT4 treatment. LT4 therapy significantly increased values of ejection fraction (EF), global longitudinal, circumferential and radial strains (P < .001, P < .001, P < .001, respectively).

CONCLUSIONS

Our study confirmed an echocardiographic improvement of cardiac structure and function in treated individuals. Findings suggest the role of electrocardiographic and echocardiographic examination in objective monitoring for LT4 therapeutic effects.