Syncope during sleep in a child with hereditary long QT syndrome (case report)

Genetically determined long QT syndrome is characterized by attacks of loss of consciousness against the background of episodes of malignant ventricular arrhythmias. Due to the high risk of sudden cardiac death, timely diagnosis of this pathology is of great importance. In the given clinical observation, the manifestation of the syndrome of an extended QT interval in a 5-year-old boy is described. The manifestations of the disease were short-term episodes of loss of consciousness, which developed during sleep in the morning during the transition of sleep phases: "sleep - wakefulness". Clinically, this was expressed by crying, straining, pallor of the skin, followed by a complete loss of muscle tone and involuntary urination. Examination on a standard electrocardiogram revealed a significant lengthening of the absolute and corrected QT interval. During the daily monitoring of the electrocardiogram, pre-morning paroxysm of frequent ventricular extrasystole was revealed, against which a burst of tachycardia "pirouette" was recorded with a heart rate of 138 beats / min, lasting 8 seconds. The patient was prescribed antiarrhythmic therapy, against the background of which a positive effect was obtained in the form of the disappearance of clinical symptoms, a reduction in the duration of the QT interval (absolute and corrected), the absence of bursts of ventricular tachycardia "pirouette" with repeated daily recordings of the electrocardiogram. Clinical observation demonstrates the need for timely in-depth cardiological examination of patients with syncope.

long QT interval syndrome, syncope, bradycardia, pirouette tachycardia, early manifestation, risk of sudden death