title: An unusual case of intermittent atrial parasystole in the fetus during labor.
abstract: An unusual fetal arrhythmia, detected during labor by continuous monitoring of fetal heart rate, is here described. This event was characterized by a double rhythm, one at high rate (137 bpm) and the other at low rate (127 bpm). An ECG simultaneously recorded, allowed the measurement of the P-P intervals, which were 438 and 424 msec, alternatively. Meanwhile, the P-Q intervals were of 84 and 75 msec, respectively. On the basis of the ECG waves morphology as well as of the different P-Q intervals, the diagnosis of intermittent atrial parasystole was posed. While the high rate rhythm seems to originate from the sinus node, the low rate rhythm seems to be parasystolic and to arise from an ectopic pace-maker, situated in the atrium in an intermediate location between sinus node and the A-V node.
mesh_terms: D001145:Arrhythmias, Cardiac / Q000175:diagnosis*; D004562:Electrocardiography; D005260:Female; D005318:Fetal Heart / Q000503:physiopathology*; D005323:Fetal Monitoring; D006801:Humans; D007743:Labor, Obstetric; D011247:Pregnancy