Arrhythmia Management in Pregnancy – HRS Consensus 2023
Arrhythmia Management in Pregnancy – HRS Consensus 2023
Source: ESC Guidelines on CVD in Pregnancy (ESC Congress, Aug 30, 2025) – complementing HRS Consensus on Arrhythmias in Pregnancy (Sept 2023).
1. Why Important
• First unified, evidence-based statement for arrhythmias in pregnancy.
• Multidisciplinary: cardiology, EP, obstetrics, neonatology, genetics.
• Provides recommendations, classes, and levels of evidence.
2. Common Arrhythmias
• Palpitations frequent; often benign (sinus tachycardia, PACs).
• SVT most common clinically significant arrhythmia.
• VT/VF or AV block rare; usually with structural/congenital disease.
3. Diagnostic Approach
• History, physical exam, 12-lead ECG, targeted labs (anemia, thyroid, electrolytes).
• Holter or event monitor if recurrent; implantable monitor if persistent suspicion.
• EPS (Electrophysiology Study) not first-line.
4. Atrial Fibrillation in Pregnancy
• Unstable: Cardioversion safe (same energy as non-pregnant).
• Stable: IV beta-blockers first line → then calcium channel blockers or digoxin.
• Class IIa: flecainide or ibutilide if others fail.
• Anticoagulation:
• Guided by CHA₂DS₂-VASc (not validated in pregnancy but still used).
• DOACs contraindicated in pregnancy & breastfeeding.
• Heparin or warfarin follow prosthetic/mechanical valve guidelines.
5. Invasive Procedures
• Catheter ablation or device implantation possible with 3D mapping, minimal radiation.
• Avoid “lead apron on abdomen” (increases scatter dose).
6. Postpartum & Lactation
• Drugs crossing breast milk: digoxin, propranolol, metoprolol, verapamil.
• Safer alternatives: carvedilol, esmolol, procainamide, diltiazem, flecainide, sotalol.
• Avoid amiodarone if possible.
7. Inherited Arrhythmia Syndromes
• Long QT: continue beta-blockers (nadolol/propranolol, caution in lactation).
• Brugada: avoid fever, avoid QT-prolonging drugs.
• CPVT (Catecholaminergic Polymorphic Ventricular Tachycardia): rare stress/exercise-induced polymorphic VT → treat with beta-blockers ± flecainide; sometimes sympathectomy or ICD.
8. Anticoagulation in Pregnancy – Key Clarifications
• Warfarin:
• Most effective for mechanical valves.
• Risk of teratogenicity, especially (first trimester).
• LMWH (Low-Molecular-Weight Heparin):
• Used in first trimester to reduce fetal risk.
• Transition back to warfarin in 2nd trimester if dose ≤5 mg/day and INR monitoring available.
• Near delivery (week 36–37) → switch again to LMWH or UFH for easier management at labor.
• Safe for fetus (does not cross placenta).
• LMWH (Low-Molecular-Weight Heparin): Requires anti-Xa monitoring (target peak 0.8–1.2 IU/mL, 4–6h post-dose).
• Frequency:weekly or(every 1–2 weeks if stable).
• Without monitoring → unsafe (risk of maternal valve thrombosis).
• UFH (Unfractionated Heparin):
• Alternative if LMWH monitoring not available.
• Monitor aPTT every 2–3 days until stable, then regularly.
• Target: 1.5–2.5 × control.
• Less convenient (multiple daily injections, frequent labs).
• Warfarin:
• If anti-Xa or aPTT monitoring not available → warfarin is most reliable despite fetal risks.
• Decision based on gestational age + shared decision-making.
• DOACs:
• Strictly contraindicated in pregnancy and lactation.
9. Syncope in Pregnancy
• Occurs in ~1%.
• Often vasovagal or orthostatic in late pregnancy (uterine compression of IVC).
• Workup: history, exam, ECG, echo, monitoring.
• EPS not indicated if exam and imaging normal.
10. Key Messages
• Most arrhythmias in pregnancy are benign.
• When intervention needed: cardioversion and beta-blockers are safe.
• Anticoagulation follows mechanical valve rules (warfarin or LMWH with monitoring).
• DOACs are contraindicated.
• Shared decision-making is essential: care must balance maternal and fetal safety.
