Accelerated idioventricular rhythm during spinal anesthesia for cesarean section

During cesarean section under regional anesthesia various anomalies of the electrocardiogram are reported such as bradycardia, supraventricular and ventricular premature beats, supraventricular paroxysmal tachicardia, S-T depression non-significant for myocardial ischemia and second degree atrioventricular block. We describe two cases of accelerated idioventricular rhythm in patients undergoing elective cesarean section with spinal anesthesia of which we have not found mention in the literature. This arrhythmia is not dangerous and does not usually evolve into ventricular fibrillation. During spinal anesthesia, however, it can exacerbate hypotension and, if misdiagnosed, a further administration of ephedrine can increase the duration of accelerated idioventricular rhythm. When necessary, for example in symptomatic hypotension or severe bradycardia, atropine is advised in order to inhibit vagal tone and increase the activity of the sino-atrial node, obtaining a pharmacological overdrive. This therapy is appropriate even if the frequency of the accelerated idioventricular rhythm is high. (C) 2003 Elsevier Science Ltd. All rights reserved.