A Rare Case of Ventricular Standstill and High-Grade AV Block in Patient with Thyrotoxicosis
Stokes-Adams Syndrome can be caused by high-grade AV Block, ventricular tachycardia, and one of the uncommon cause, ventricular standstill. Although thyrotoxicosis is commonly presented as tachycardia, it’s unusual for AV blocks to occur, especially a high-grade one.
A 45-year-old female was admitted with fatigue, dizziness, and recurrent episodes of unconsciousness. She had a history of hyperthyroid, routinely managed with Propylthiouracil and Propranolol. Physical examination showed HR: 30 x/min, and other unremarkable systemic examinations. Initial ECG showed 3:1 AV Block. Patient was managed with Dopamin and moved to ICU for further observation. In the ICU, suddenly she had a Stokes-Adam episode presented as a seizure, her monitor showing P waves with an absence of ventricular activity lasting for few seconds. Due to the condition of ventricular standstill, a Temporary Pacemaker (TPM) was installed urgently, and so patient’s vital sign was stable with pacing rhythm. We found Free Thyroxine (T4) level of 46.85 pmol/l, TSH of 0.005 ulU/ml, and unremarkable echocardiographic findings. Considering these results, we suspect that the cause of the ventricular standstill was due to thyrotoxicosis. Propylthiouracil and dexamethasone were given to manage the disease. After 7 days of treatment, she was discharged with sinus rhythm on her ECG.
Ventricular standstill is frequently associated with conduction blockages, but it can sometimes occur without them. Ventricular standstill treatment often necessitates the use of temporary pacing wires or a pacemaker. In thyroid crises, high-degree AV-block is uncommon, but when the euthyroid condition is restored, clinical status and conduction problems can be reversible.
 Adegoke D A. Paroxysmal Ventricular Standstill: A Rare Cardiac. American Journal of Case Reports. 2020;21:e924381.
 Vassalle M. On the Mechanisms Underlying Cardiac Standstill: Factors Determining Success or Failure of Escape Pacemakers in the Heart. Journal of American College of Cardiology. 1985; 5(6):35-42
 Panchal A R. et al. 2020 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2020;142(16): S366-S468.
 Kusumoto F. H. et al. 2018 ACC/AHA/HRS Guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay : A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhyt. Heart Rhythm. 2019;16(9):130-226.
 Latt H. et al. A Case of Ventricular Standstill in a Patient with Acute Gastroentestinal Bleeding. Journal of Community Hospital Internal Medicine Perspective. 2020;10(3):283-286
 Jaiswal, S, Aldave A P N, Wool K J. Ventricular standstill: An uncommon electrophysiological abnormality caused by profound vagal tone. North American Journal of Medical Science. 2014; 6(4):178-180
 Mu Y, Supino M. A Case of Elusive Cardiac dysrhytmia in high-risk syncope. American Journal of Emergency Medicine. 2019; 37(10): 1992.e1-1992.e3.
 El-Harasis M. A. et al. Graves’ disease–induced complete heart block and asystole. Heart Rhythm Case Reports. 2018; IV(3):105-108.
 Cookson, H. Paroxysmal Ventricular Standstill. British Heart Journal. 1952;14(3):350-356.
 Moles W J. et al. Incidental Findings of Asystole in a Patient With Complaints of Near Syncope: A Case Report on Paroxysmal Ventricular Standstill. Cureus. 2021;13(10):e18438
 Vennard K, Gilbert M P. Thyroid Storm and Complete Heart Block after treatment with Radioactive Iodine. HIndawi Case Report of Endocrinology. 2018;8214169: 1-3.
 Ortmann C, Pfeiffer H, Du Chesne A, Brinkmann B. Inflammation of the cardiac conduction system in a case of hyperthyroidism. International Journal of Legal Medicine.1999;112:271-274
 Shirani J, Barron M M, Pierre-Louis M L Y, Roberts W C. Congestive heart failure, dilated cardiac Ventricles, and Sudden Death in Hyperthyroidsm. The American Journal of Cardiology. 1993;72(3):365-368
 Ozcan K S. et al. Atrioventricular block in patients with thyroid dysfunction: Prognosis after treatment with hormone supplementation or antithyroid medication. Journal of Cardiology. 2012;60:327-332
 Abubakar H, Singh V, Arora A, Alsunaid S. Propranolol-Induced Circulatory Collapse in a Patient With Thyroid Crisis and Underlying Thyrocardiac Disease: A Word of Caution. Journal of Investigative Medicine High Impact Case Reports.2017;78:1-6
 Ngo A, Tan D. Thyrotoxic Heart Disease. Resuscitation. 2006;70:287-290
 Dalan R, Leow M. Cardiovascular collapse associated with beta blockade in thyroid storm. Exp Clin Endocrinol Diabetes. 2007; 115:392-396
 Moseley B, Ghearing G, Munger T, Britton J. The treatment of ictal asystole with cardiac pacing. Epilepsia. 2011;52(4):e16-19
 Lende M, Surges R, Sanders J W, Thijs R D. Cardiac arrhythmia during or after epileptic seizures. J Neurol Neurosurg Psychiatry. 2016.;87:69-74
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