Methods: Atrial premature beats are frequently diagnosed during pregnancy, supraventricular tachycardia (atrial tachycardia, AV nodal reentrant tachycardia, circus movement tachycardia) less frequently. For acute therapy, electrical cardioversion with 50-100 J is indicated in all unstable patients. In stable supraventricular tachycardia, initial therapy includes vagal maneuvers to terminate breakthrough tachycardias. For short-term management, when vagal maneuvers fail, intravenous adenosine is the drug of first choice and may safely terminate the arrhythmia. For long-term therapy, beta-blocking agents with beta(1) selectivity are first-line drugs; class Ic agents or the class III drug sotalol represent effective and therapeutic alternatives. Ventricular premature beats are also frequently present during pregnancy and benign in most of the unstable patients; however, malignant ventricular tachyarrhythmias (sustained ventricular tachycardia, ventricular flutter, ventricular fibrillation) are less frequently observed. Electrical cardioversion is necessary in all patients with hemodynamically unstable situation and life-threatening ventricular tachyarrhythmias; in hemodynamically stable patients, initial therapy with ajmaline, procainamide or lidocaine is indicated. If prophylactic therapy is needed, beta-blocking agents with beta(1) selectivity are regarded as drugs of first choice. If this therapy proves ineffective, class Ic agents or sotalol can be considered. In patients with syncopal ventricular tachycardia, ventricular fibrillation, ventricular flutter or aborted sudden death, an implantable cardioverter-defibrillator is indicated. In patients with symptomatic bradycardia, a pacemaker can be implanted using echocardiography at any stage of pregnancy.
Conclusions: The treatment of the pregnant patient with cardiac arrhythmias requires important modifications of the standard practice of arrhythmia management. The goal of therapy is to protect the patient and fetus through delivery, after which chronic or definitive therapy can be administered.