Evaluation of Cardiac Electrophysiological Balance in Patients with Subclinical Hypothyroidism

Year 2022, Volume: 25 Issue: 1, 77 - 84, 18.04.2022

Faysal Şaylık Tufan Çınar Murat Selçuk Tayyar Akbulut

Abstract

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.

Keywords

Hypothyroidism, cardiac electrophysiology, cardiac arrhythmia

References

• 1. Eidan E, Ur Rahman S, Al Qahtani S, Al Farhan AI, Abdulmajeed I. Prevalence of subclinical hypothyroidism in adults visiting primary health-care setting in Riyadh. J Community Hosp Intern Med Perspect 2018;8:11-5. [Crossref]
• 2. Rodondi N, Bauer DC, Cappola AR, Cornuz J, Robbins J, Fried LP, et al. Subclinical thyroid dysfunction, cardiac function, and the risk of heart failure. J Am Coll Cardiol 2008;52:1152-9. [Crossref]
• 3. Hak AE, Pols HAP, Visser TJ, Drexhage HA, Hofman A, Witteman JCM. Subclinical hypothyroidism is an independent risk factor for atherosclerosis and myocardial infarction in elderly women: the Rotterdam study. Ann Intern Med 2000;132:270-8. [Crossref]
• 4. Krstevska B, Bosevski M, Ch D, Serafimoski V. Dyslipidaemia and hypertension in patients with subclinical hypothyroidism. Prilozi 2009;30:93-102.
• 5. Rastgooye Haghi A, Solhjoo M, Tavakoli MH. Correlation between subclinical hypothyroidism and dyslipidemia. Iran J Pathol 2017;12:106-11. [Crossref]
• 6. Lip GYH, Coca A, Kahan T, Boriani G, Manolis AS, Olsen MH, et al. Hypertension and cardiac arrhythmias: a consensus document from the European Heart Rhythm Association (EHRA) and ESC Council on Hypertension, endorsed by the Heart Rhythm Society (HRS), Asia-Pacific Heart Rhythm Society (APHRS) and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE). EP Europace 2017;19:891-911. [Crossref]
• 7. Bhar-Amato J, Davies W, Agarwal S. Ventricular Arrhythmia after acute myocardial infarction: ‘the perfect storm’. Arrhythm Electrophysiol Rev 2017;6:134-9. [Crossref]
• 8. Masarone D, Limongelli G, Rubino M, Valente F, Vastarella R, Ammendola E, et al. Management of arrhythmias in heart failure. J Cardiovasc Dev 2017;4:3. [Crossref]
• 9. Liu YB, Wu CC, Lee CM, Chen WJ, Wang TD, Lee YT, et al. Dyslipidemia is associated with ventricular tachyarrhythmia in patients with acute st-segment elevation myocardial infarction. J Formos Med Assoc 2006;105:17-24. [Crossref]
• 10. Imaizumi M, Akahoshi M, Ichimaru S, Nakashima E, Hida A, Soda M, et al. Risk for ischemic heart disease and all-cause mortality in subclinical hypothyroidism. J Clin Endocrinol Metab 2004;89:3365-70. [Crossref]
• 11. Kim EJ, Lyass A, Wang N, Massaro JM, Fox CS, Benjamin EJ, et al. Relation of hypothyroidism and incident atrial fibrillation (from the Framingham heart study). Am Heart J 2014;167:123-6. [Crossref]
• 12. Park YJ, Yoon JW, Kim KI, Lee YJ, Kim KW, Choi SH, et al. Subclinical hypothyroidism might increase the risk of transient atrial fibrillation after coronary artery bypass grafting. Ann Thorac Surg 2009;87:1846-52. [Crossref]
• 13. Gürdal A, Eroğlu H, Helvaci F, Sümerkan MÇ, Kasali K, Çetin Ş, et al. Evaluation of Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in patients with subclinical hypothyroidism. Ther Adv Endocrinol Metab 2017;8:25-32. [Crossref]
• 14. Galetta F, Franzoni F, Fallahi P, Rossi M, Carpi A, Rubello D, et al. Heart rate variability and QT dispersion in patients with subclinical hypothyroidism. Biomed Pharmacother 2006;60:425-30. [Crossref]
• 15. Ojamaa K, Sabet A, Kenessey A, Shenoy R, Klein I. Regulation of rat cardiac kv1.5 gene expression by thyroid hormone is rapid and chamber specific. Endocrinology 1999;140:3170-6. [Crossref]
• 16. Bakiner O, Ertorer ME, Haydardedeoglu FE, Bozkirli E, Tutuncu NB, Demirag NG. Subclinical hypothyroidism is characterized by increased QT interval dispersion among women. Med Princ Pract 2008;17:390-4. [Crossref]
• 17. Jadhav V, Kammar KF. Electrocardiographic changes in subclinical hypothyroidism. Natl J Physiol Pharm Pharmacol 2020;10. [Crossref]
• 18. Castro-Torres Y, Carmona-Puerta R, Katholi RE. Ventricular repolarization markers for predicting malignant arrhythmias in clinical practice. World J Clin Cases 2015;3:705-20. [Crossref]
• 19. Tanrıverdi Z, Çöllüoğlu T, Ünal B, Dursun H, Kaya D. The effect of transcatheter aortic valve implantation on Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, and Tp-e dispersion in patients with severe aortic stenosis. Türk Göğüs Kalp Damar Cerrahisi Derg 2018;26:65-72. [Crossref]
• 20. Lang RM, Bierig M, Devereux RB, Flachskampf FA, Foster E, Pellikka PA, et al. Recommendations for Chamber Quantification: A Report from the American Society of Echocardiography 2019; Guidelines and Standards Committee and the Chamber Quantification Writing Group, Developed in Conjunction with the European Association of Echocardiography, a Branch of the European Society of Cardiology. J Am Soc Echocardiogr 2005; 18:1440-63. [Crossref]
• 21. Tei C, Nishimura RA, Seward JB, Tajik AJ. Noninvasive Doppler-derived myocardial performance index: Correlation with simultaneous measurements of cardiac catheterization measurements. J Am Soc Echocardiogr 1997;10:169-78. [Crossref]
• 22. Topilski I, Rogowski O, Rosso R, Justo D, Copperman Y, Glikson M, et al. The morphology of the QT interval predicts torsade de pointes during acquired bradyarrhythmias. J Am Coll Cardiol 2007; 49:320-8. [Crossref]
• 23. Haarmark C, Hansen PR, Vedel-Larsen E, Haahr Pedersen S, Graff C, Andersen MP, et al. The prognostic value of the Tpeak-Tend interval in patients undergoing primary percutaneous coronary intervention for ST-segment elevation myocardial infarction. J Electrocardiol 2009;42:555-60. [Crossref]
• 24. Shimizu M, Ino H, Okeie K, Yamaguchi M, Nagata M, Hayashi K, et al. T-peak to T-end interval may be a better predictor of high-risk patients with hypertrophic cardiomyopathy associated with a cardiac troponin i mutation than qt dispersion. Clin Cardiol 2002;25:335-9. [Crossref]
• 25. Yan GX, Antzelevitch C. Cellular basis for the normal T wave and the electrocardiographic manifestations of the Long-QT syndrome. Circulation 1998;98:1928-36. [Crossref]
• 26. Kilicaslan F, Tokatli A, Ozdag F, Uzun M, Uz O, Isilak Z, et al. Tp-e interval, Tp-e/QT ratio, and Tp-e/QTc ratio are prolonged in patients with moderate and severe obstructive sleep apnea. PACE 2012;35:966-72. [Crossref]
• 27. Ucar FM, Ozturk C, Yılmaztepe MA. Evaluation of Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio in patients with acute myocarditis. BMC Cardiovasc Disord 2019;19:232. [Crossref]
• 28. Hondeghem LM. Disturbances of cardiac wavelength and repolarization precede Torsade de Pointes and ventricular fibrillation in Langendorff perfused rabbit hearts. Prog Biophys Mol Biol 2016;121:3-10. [Crossref]
• 29. Tse G. Both transmural dispersion of repolarization and transmural dispersion of refractoriness are poor predictors of arrhythmogenicity: a role for the index of cardiac electrophysiological balance (QT/QRS)? J Geriatr Cardiol 2016;13(9):813-4.
• 30. Tse G, Wong S, Tse V, Yeo J. Depolarization vs. repolarization: what is the mechanism of ventricular arrhythmogenesis underlying sodium channel haploinsufficiency in mouse hearts? Acta Physiol (Oxf). 2016;218:234-5. [Crossref]
• 31. Robyns T, Lu HR, Gallacher DJ, Garweg C, Ector J, Willems R, et al. Evaluation of index of cardio-electrophysiological balance (iCEB) as a new biomarker for the identification of patients at increased arrhythmic risk. Ann Noninvasive Electrocardiol 2016;21:294-304. [Crossref]
• 32. Askin L, Tanrıverdi O. Evaluation of index of cardio-electrophysiological balance in patients with coronary slow flow. Acta Cardiol 2021:1-5. [Crossref]
• 33. Alsancak Y, Gürbüz AS, Saklı B, İçli A. Evaluation of index of cardio-electrophysiological balance and Tp-e/QT ratio in patients with coronary artery ectasia. J Surg and Med 2019;3:223-6. [Crossref]
• 34. Sivri S, Çelik M. Evaluation of index of cardiac-electrophysiological balance before and after hemodialysis in patients with end-stage renal disease. J Electrocardiol 2019; 54:72-5. [Crossref]
• 35. Özdemir L, Sökmen E. Effect of habitual cigarette smoking on the index of cardiac electrophysiological balance in apparently healthy individuals. J Electrocardiol 2020; 59:41-4. [Crossref]