This handout is for atrial flutter / iart in adult congenital heart disease (achd). Your care team identified this based on: sustained atrial tachycardia / iart in adult with prior fontan palliation (single-ventricle physiology) — high-risk hemodynamic substrate; achd center referral mandatory.
Other reasons your team may use this plan: sustained atrial tachycardia / iart in adult with prior mustard or senning atrial-switch repair for d-tga — risk of 1:1 av conduction and systemic rv failure; sustained atrial tachycardia / iart in adult with repaired tetralogy of fallot, asd, vsd, avsd, or other congenital lesion with atrial scar substrate; palpitations / dyspnea / fatigue / syncope in adult with known congenital heart disease history — high pre-test probability of iart.
Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.
| Medication | Starting dose | How | When | What it does |
|---|---|---|---|---|
| amiodarone | 150 mg IV over 10 min then 1 mg/min × 6 h then 0.5 mg/min × 18 h; 200 mg PO daily maintenance; consider lower long-term dose (100 mg) given decades of anticipated use in young ACHD patients | IV/PO | load + daily | Most efficacious AAD for ACHD IART with structural heart disease; class IC contraindicated per CAST (PMID 1900101); pulm/thyroid/LFT toxicity matters more in young ACHD patients with decades of anticipated treatment — ACC/AHA 2024 (PMID 38753446); PACES/HRS 2014 (PMID 24681262) |
| sotalol | 40 mg PO BID titrate to 80–160 mg BID per CrCl + QTc monitoring (REMS-equivalent inpatient initiation) | PO | BID | Alternative class III AAD with BB activity; CrCl-adjusted dosing; QTc monitoring mandatory; useful when amiodarone toxicity limits use — ACC/AHA 2024 (PMID 38753446) |
| dofetilide | 125–500 mcg PO BID per CrCl (REMS — inpatient initiation × 3 days minimum) | PO | BID | Alternative to amiodarone/sotalol; dofetilide REMS — must be initiated inpatient with QTc + CrCl monitoring; less ventricular dysfunction risk than other class III — ACC/AHA 2024 (PMID 38753446) |
| metoprolol | metoprolol succinate 12.5–25 mg PO daily titrate cautiously (target HR 70–90; LOWER than typical flutter due to systemic ventricular failure risk) | PO | daily | CAUTIOUS rate control add-on; AVOID if failing systemic RV or failing Fontan (worsens forward flow); target HR 70–90 (lower than standard flutter target) — ACC/AHA 2024 (PMID 38753446); PACES/HRS 2014 |
| apixaban | 5 mg BID (2.5 mg BID if 2 of: ≥80 yr, ≤60 kg, Cr ≥1.5) | PO | BID | AC essentially universal in ACHD IART per PACES/HRS 2014 (PMID 24681262) — overrides CHA2DS2-VASc score; lifelong AC typical given lifelong substrate — ARISTOTLE (PMID 21870978); ACC/AHA 2024 Class I |
| warfarin | INR target 2–3 (or 2.5–3.5 in mechanical valve) | PO | daily | Warfarin often preferred in Fontan + complex cyanotic ACHD due to limited DOAC safety data in this population; mechanical-valve mandatory; ACC/AHA 2024 + PACES/HRS 2014 |
| unfractionated heparin | 60 U/kg IV bolus then 12 U/kg/h to PTT 1.5–2× control (max 4000 U bolus) | IV | continuous | Bridge AC for acute arrhythmia management; transition to DOAC/warfarin per long-term plan — ACC/AHA 2024 + PACES/HRS 2014 |
Plan: IART in adult congenital heart disease — rhythm-control-preferred (rate-only inadequate in failing systemic RV) + universal AC (PACES/HRS 2014 override of CHA2DS2-VASc) + ACHD-center 3D electroanatomic mapping ablation pathway — ACC/AHA 2024 (Joglar PMID 38753446); PACES/HRS 2014 (Khairy PMID 24681262); 2018 ACC/AHA ACHD (Stout PMID 30121239); ESC 2020 ACHD (Baumgartner PMID 32860028)
Contact your care team if any of the following happen:
Call 911 or go to the nearest emergency room right away if you have:
ACHD-center cardiology q3–6 mo; AC continuation indefinite (lifelong); post-ablation 4-week ECG + Holter at 3/6/12 mo for IART/AF screen; pacemaker interrogation if applicable; systemic ventricular function surveillance; pregnancy counseling (high-risk in ACHD with arrhythmia + AC); cardiac rehab (ACHD-specific protocol); mental-health support (chronic-disease anxiety high in ACHD)
Guideline: 2024 ACC/AHA/ACCP/HRS AF + AFL Joint Guideline ACHD subsection (Joglar Circulation 2024 PMID 38753446); 2018 ACC/AHA ACHD Management Guideline (Stout Circulation 2018 PMID 30121239); PACES/HRS 2014 Expert Consensus on Recognition and Management of Arrhythmias in ACHD (Khairy Heart Rhythm 2014 PMID 24681262); 2020 ESC Adult Congenital Heart Disease Guideline (Baumgartner EHJ 2021 PMID 32860028)