Generalized myoclonus following dobutamine stress echocardiography: a case report

Background Dobutamine stress echocardiography (DSE) is a widely used and generally safe non-invasive imaging modality for the assessment of myocardial ischemia. Adverse effects are predominantly cardiovascular, whereas neurological complications are exceedingly rare. Dobutamine-induced myoclonus (DIM) has only rarely been reported, mainly in patients receiving prolonged dobutamine infusions for heart failure or cardiomyopathy. Case summary A 47-year-old woman underwent DSE for evaluation of exertional chest pain. Following completion of a standard dobutamine protocol, she developed generalized rhythmic myoclonic jerks predominantly involving the axial musculature. The patient remained fully conscious and hemodynamically stable throughout the episode. Intravenous diazepam failed to improve symptoms, whereas complete resolution occurred after administration of intravenous valproic acid. Laboratory investigations, including electrolytes, renal function, and thyroid function tests, were normal. Electroencephalography and brain magnetic resonance imaging revealed no abnormalities. No recurrence was observed during hospitalization or follow-up. Discussion To our knowledge, this is the first reported case of DIM occurring immediately after DSE. Unlike previously published cases, which predominantly involved patients with chronic kidney disease and developed after prolonged dobutamine exposure, our patient had normal renal function and developed symptoms immediately upon completion of the stress protocol. The pathophysiology remains uncertain, although increased central nervous system exposure to dobutamine has been proposed. Clinicians performing DSE should be aware of myoclonus as a rare but important neurological complication, and should consider valproic acid when benzodiazepines fail to achieve symptom control.