The Unexpected Pitter Patter: New-Onset Atrial Fibrillation in Pregnancy

Table 1

Drug	Rate versus rhythm control	Class of recommendation/level of evidence	FDA category	Dosage	Adverse effects
Beta-blockers	Rate	Class IIa/C	C		Pregnancy: born small for gestational age, preterm birth, and perinatal mortality [1]. General: bradycardia, hypotension, AV block, bronchospasm
Esmolol				Loading: 0.5 mg/kg over 1 min. Maintenance: 0.06–0.2 mg/k/min
Metoprolol				2.5–5 mg bolus over 2 min, up to 3 doses
Propranolol				0.15 mg/kg
Nondihydropyridine calcium channel blockers	Rate	Class IIa/C	C		Pregnancy: increased risk of neonatal seizures, jaundice, and hematologic disorders [2]. General: hypotension, heart failure
Diltiazem				Loading: 0.25 mg/kg/dose over 2 min; may give a second dose at 0.35 mg/kg/dose. Maintenance: 5–15 mg/kg for <24 hr.
Verapamil				0.075–0.15 mg/kg over 2 min
Cardiac glycoside
Digoxin	Rate	Class IIb/C	C	Loading: 0.25 mg IV every 2 h, up to 1.5 mg.; Maintenance 0.125–0.375 mg daily IV or orally	Pregnancy: digitalis toxicity may cause fetal demise [3]. General: digitalis toxicity, heart block
Class I C antiarrhythmic agent
Flecainide	Rhythm	Class IIb/C	C		General: heart block, ventricular arrhythmias, and heart failure
Class III antiarrhythmic agent
Ibutilide	Rhythm	Class IIb/C	C	1 mg IV; may repeat dose if no response after 10 min	General: bradycardia, AV block, Torsades
Adjunctive therapies
Magnesium		NA	B	2 g over 15 min	General: respiratory depression