ABC | Volume 112, Nº5, May 2019

Guideline Brazilian Fetal Cardiology Guidelines – 2019 Arq Bras Cardiol. 2019; 112(5):600-648 Table 7.3 – In utero management of tachycardias Diagnosis In utero management GOR/LOE Comments Intermittent tachycardia SVT or AF Observation I/B Frequent fetal HR auscultation VT ≥ 200 bpm Antiarrhythmic medication IIa/C Sustained tachycardia SVT or AF with hydrops or ventricular dysfunction First or second line (transplacental) drugs: See Table 7.4, for dosing ranges and monitoring recommendations Digoxin I/B Sotalol I/B Combination of drugs (transplacental) IIb/B Combination treatments are used for severe, drug-refractory cases. Consider preterm delivery if near term Third line (transplacental): Amiodarone I/B Contraindicated: verapamil III/A Contraindicated: procainamide III/B Direct fetal treatment: IM digoxin IIa/B Intracordal digoxin IIb/B Contraindicated: Intracordal adenosine III/B SVT ≥ 200 bpm, without hydrops or ventricular dysfunction (usually SVT has HR ≥ 220 bpm; consider other causes if HR < 220 bpm). First or second line: Digoxin I/B See Table 7.4, for doses and monitoring recommendations Sotalol I/B Frequent monitoring of fetal well-being and maternal/fetal drug toxicity. Consider preterm delivery if near term. Third line: Amiodarone IIb/B Contraindicated: verapamil IIb/A Contraindicated: procainamide III/B Observation I/B SVT < 200 bpm, without hydrops or ventricular dysfunction Sotalol I/B Digoxin increases AVB and decreases ventricular response. Consider preterm delivery if near term AF Digoxin I/B Amiodarone IIb/B Contraindicated: procainamide III/B VT ± hydrops I/C First line treatment Magnesium IV Lidocaine IV Propranolol (oral) I/C FMCG (if available) to measure QTc interval. Start with magnesium IV, then lidocaine, load + maintenance. Note: maternal intravenous magnesium should not be used for > 48 h. Consider preterm delivery if near term. Second line treatment Mexiletina (oral) Sotalol I/C AF: atrial flutter; GOR: grade of recommendation; IV: intravenous; HR: heart rate; IM: intramuscular; FMCG: fetal magnetocardiography; LOE: level of evidence; SVT: supraventricular tachycardia; VT: ventricular tachycardia. Source: adapted from Donofrio MT et al. 17 632