Subclinical hypothyroidism was associated with significantly prolonged cardiac electrophysiological balance (iCEB 4.6 vs 4.4, p=0.014) compared to healthy controls.
Case-Control (n=164)
No
Does subclinical hypothyroidism prolong cardiac electrophysiological balance (iCEB and iCEBc) compared to healthy controls?
Subclinical hypothyroidism is associated with prolonged cardiac electrophysiological balance (iCEB and iCEBc), suggesting a potential non-invasive marker for increased arrhythmic risk in these patients.
Absolute Event Rate: 4.6% vs 4.4%
p-value: p=0.014
Introduction: Subclinical hypothyroidism (SH) is defined by slightly elevated thyroid-stimulating hormone (TSH) levels with normal free triiodothyronine (fT3) and thyroxine (fT4) levels. SH is related to cardiovascular events, including malignant arrhythmias. Cardiac electrophysiological balance (iCEB) and its corrected form with heart rate (iCEBc) are useful electrocardiographic (ECG) parameters for the prediction of malign arrhythmias. In this study, we aimed to evaluate iCEB and iCEBc in SH patients. Patients and Methods: A total of 164 patients (n= 82 patients with SH and n= 82 controls) were enrolled in this study. iCEB was calculated by dividing QT by QRS, and iCEBc was calculated by dividing corrected QT (QTc) by QRS. The groups were compared based on ECG parameters. Correlation and multiple linear regression analyses were used to assess the association of ECG parameters with TSH levels. Results: There were no differences between the groups regarding clinical and laboratory findings. Tp-e, QT, QTc, Tp-e/QT, Tp-e/QTc, iCEB, and iCEBc were significantly prolonged in SH patients compared to controls. In correlation analyses, all of the abovementioned ECG parameters were significantly correlated with serum TSH levels. Multiple linear regression analysis indicated that Tp-e, iCEB, and iCEBc were independently associated with serum TSH levels in SH patients. Conclusion: To our knowledge, this was the first study to demonstrate that iCEB and iCEBc were both prolonged in SH patients compared to controls, and both of them were independently correlated with TSH levels in such patients.
Şaylık et al. (Fri,) conducted a case-control in Subclinical Hypothyroidism (n=164). Subclinical hypothyroidism vs. Healthy controls was evaluated on Cardiac electrophysiological balance (iCEB) (p=0.014). Subclinical hypothyroidism was associated with significantly prolonged cardiac electrophysiological balance (iCEB 4.6 vs 4.4, p=0.014) compared to healthy controls.