Incessant Atrial Tachycardia and a Cerebral Tumor

A 78-year-old woman with no history of heart disease or any other pathological process was seen in the outpatient clinic for a routine check-up. Cardiac arrhythmia was detected at this visit and she was referred to our center. The patient was completely asymptomatic and the physical examination was unremarkable. The only evaluable cardiologic feature was a relatively rapid and irregular pulse rate. The resting ECG demonstrated short runs of atrial rhythm, usually a few beats, originating in the high right atrium, alternating with one or two beats of sinus rhythm, and occasionally accompanied by premature supraventricular contractions of the same morphology. Heart rate was 120-140 beats/min and the findings were consistent with incessant atrial tachycardia. The PR, QRS and QTc intervals were normal. Extracardiac causes that could explain or favor the arrhythmia were ruled out and the patient denied any concomitant pharmacological treatment or toxic habits. Several subsequent studies with Holter monitoring confirmed the same cardiac rhythm abnormality, with a slight decrease in the rate and a slight increase in extrasystoles at night and during rest (Figure 1). A complete analytical study, including a repeat thyroid function test to investigate mild multinodular thyroid hyperplasia, was normal, as were the chest X-ray and echocardiogram. Despite the absence of symptoms and given the sustained character of the arrhythmia, pharmacological treatment was attempted with several antiarrhythmic BR I E F RE P O R T S