Naphazoline intoxication with transient QT prolongation and acute myocardial injury

A 27-year-old Japanese woman with a history of depression and an eating disorder presented to our emergency department with a chief complaint of generalized weakness. Electrocardiography showed prominent QT prolongation with multiple ventricular contractions. Chest X-ray plain computed tomography revealed pulmonary edema. Echocardiography showed decreased left ventricular systolic function. Suspecting acute myocarditis, we performed a myocardial biopsy from the right ventricular septum. The biopsy histology revealed extensive myocardial fibrosis and a very mild inflammatory cell infiltrate. In an additional detailed medical interview, the patient admitted that she had consumed three bottles of a first-aid liquid containing naphazoline approximately ~12 h before her presentation, in a suicide attempt. Her QTc and left ventricular ejection fraction improved during hospitalization.

Acute drug intoxication can cause QT prolongation and ventricular arrhythmias, cardiomyopathy, and pulmonary edema. When acute QT prolongation, myocardial damage, and pulmonary edema are seen (suggesting acute myocarditis), naphazoline intoxication should be investigated in the differential diagnosis.