Repetitive Monomorphic Ventricular Tachycardia in a 4‐Year‐Old Boy with Toxic Multinodular Goiter

Abstract

A case of toxic multinodular goiter associated with repetitive monomorphic ventricular tachycardia (VT) is reported. A 4-year-old boy was found to have asymptomatic VT. When treatment with antiarrhythmic agents turned out to be ineffective, thyrotoxicosis was suspected due to the rapid enlargement of the left thyroid gland and associated thyroid function studies. A diagnosis of toxic multinodular goiter was made on the basis of subsequent scintigraphy and ultrasonography. Treatment with antithyroid drugs and inorganic iodine restored the thyroid function to normal, and was accompanied by the disappearance of VT. A left thyroid lobectomy was performed, and the pathological findings were compatible with toxic multinodular goiter. After the operation, the patient was transiently hypothyroid and had no VT without medication. A review of the literature revealed no previously documented cases of VT with toxic multinodular goiter.

Graves' Disease Complicated by Ventricular Fibrillation in Three Men Who Were Smokers

“…These cases have additional common clinical features such as no family history of sudden cardiac death, no history of syncope attack, and no identifiable causes accounting for VT or Vf, which are thus idiopathic. Interestingly, in four cases found in the literature (10,11,13,14), no ventricular arrhythmias were recorded after the thyroid function was controlled, and therefore, the patients needed only temporary medical treatments for ventricular arrhythmia and did not require the implantation of an ICD. The disappearance of Vf as a result of the improvement of thyroid function was also seen in Patient 1 and Patient 2 in the present study.…”

“…Ischemic heart disease is another cause of Vf seen in patients with thyrotoxicosis, probably because thyroid hormone is known to increase cardiac oxygen consumption (2). Thus, it is even rarer for thyrotoxic patients not accompanying hypokalemic periodic paralysis to develop Vf without ischemic heart disease (10)(11)(12)(13)(14) or with stable coronary disease (15). We present three cases of GD complicated by idiopathic Vf without hypokalemic periodic paralysis or ischemic heart disease.…”

Incessant ventricular tachycardia due to subacute thyroiditis

“…In the first case, at a 4-year-old boy admitted because of febrile convulsions, asymptomatic, monomorphic ventricular tachycardia was noted and responded to anti-thyroid treatment after anti-arrhythmic drugs were deemed ineffective [6]. The second case involved coarse ventricular fibrillation reported to be triggered by palpation of the thyroid gland during surgery while the patient was under anesthesia [5].…”

“…In literature, it has been demonstrated that thyroid disorders can cause life-threatening ventricular arrhythmias without any underlying cardiac disease [5,6] but underlying mechanism for ventricular arrhythmias is unclear. In thyrotoxicosis, there is usually a decrease in systemic vascular resistance, an increase in cardiac output, heart rate, and systolic blood pressure, an enhanced left ventricular contractility, ejection fraction, and blood volume and a global impairment of diastolic heart performance [7,8].…”

Heart Failure in Pediatric and Adolescent Hyperthyroidism

“…But, nodular forms may also be associated to rhythmic troubles (10). Other etiologies can have the same impact on heart function, but they are less common than in adults.…”