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An Extreme Wide-Complex Tachycardia and Tremors
Samuel Kim1, Sukhmandeep Sangha1, Srisa Boddupalli1
1Wollongong Hospital, Wollongong, Australia; University of Wollongong, Wollongong, Australia.
Case Summary:
A 33-year-old gentleman presented with syncope, palpitations, and tremors. His 12-lead electrocardiogram demonstrated a wide-complex tachycardia at 300/min with intermittent changes in QRS morphology. Following urgent cardioversion, further electrocardiograms revealed the diagnosis, and biochemical testing showed hyperthyroidism secondary to Graves' disease. The patient commenced antiarrhythmic and hyperthyroid treatment and underwent definitive management with an electrophysiology study and ablation.
Take-Home Messages:
The differentials for a wide-complex tachycardia should include ventricular tachycardia, supraventricular tachycardia with aberrancy, pre-excitation, or pacing. Patients presenting with tachyarrhythmias should also be screened for hyperthyroidism as a precipitating and reversible cause.
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