Acute Tachycardia-Induced Cardiomyopathy: A Case Report.

BACKGROUND Tachycardia from atrial fibrillation or flutter can lead to left ventricular systolic dysfunction. Some patients deteriorate quickly, and there is an acute drop in their left ventricular systolic function; however, they tend to normalize rapidly after treatment of the underlying arrhythmia. The aim of publishing the present case is to maintain awareness that tachycardia is one of the etiologies of acute systolic heart failure, which is potentially reversible by treatment when recognized. CASE REPORT An 88-year-old woman with a history of hypertension and diabetes presented to the emergency department with shortness of breath and new-onset atrial fibrillation. The physical examination revealed jugular vein distention, an irregular heart rate of approximately 140 beats/min, bilateral basal lung crackles, and no murmurs. One week before this presentation, she underwent electrocardiography, which showed she was in sinus rhythm, and transthoracic echocardiography, which indicated an ejection fraction of 65%. After hospital admission, she was started on beta-blockers for heart rate control and diuretics for heart failure management. As her symptoms persisted, she underwent a transesophageal echocardiography-guided cardioversion, where her ejection fraction was 30%. A repeat transthoracic echocardiography 3 days after the cardioversion indicated the ejection fraction had normalized to 60%. She was followed up every month in the Outpatient Cardiology Clinic and has remained asymptomatic for 1 year to date. CONCLUSIONS Although most literature describes tachycardia-induced cardiomyopathy as a chronic process, it can be acute. Patients benefit from rhythm control, and with early diagnosis and appropriate management, the prognosis is good.