Table 2.
Drugs to Treat Fetal SVT and Atrial Flutter a
| Drug 2 , 6 , 12 , 25 , 27 , 28 , 31 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 | Type of Arrhythmia | F:M Drug RatioRoute | Efficacy Acute and Chronic | Elimination | Intra‐amniotic | Side Effects |
|---|---|---|---|---|---|---|
|
Digoxin Na,K‐ATPase inhibitor Class C |
SVT, AFl |
0.8:1, ↓ if hydrops to 0.2:1 PO, IV, fetal IM/IC |
50%‐60%, combined with other AA 80% | Renal | Higher, not reflected in fetal | N/V, arrhythmias, anorexia, poor weight gain |
|
Flecainide Calcium channel inhibitor Class C |
SVT, AFl, AET, PJRT, VT (non‐LQTS) |
1:1(+) PO |
60% | Renal | Up to 27× maternal serum level | CNS, bradycardia, ↑QRS, ↑QTc |
|
Sotalol Potassium channel inhibitor/beta blocker Class B |
SVT, AFl, AET, PJRT |
0.9:1(+) PO |
50%‐60% for SVT, up to 80% for AFl | Renal | 1.6‐28× maternal serum level | CNS, bradycardia, ↑QTc |
|
Amiodarone Multichannel inhibitor Class D |
SVT, AFl (±), AET, PJRT, JET, VT not if ↑QTc |
0.4:1, long half‐life after PO loading Rare IC or peritoneal administration |
90+% | Hepatic | Lipophilic, all tissues |
Bradycardia, M/F hypothyroidism, ↑QTc, breastfeeding CI |
| Adenosine | 0 | Not recommended, Direct IC administration | Low | Erythrocytes | 0 | Short‐acting |
AA, antiarrhythmic agent; AET, atrial ectopic tachycardia; AFl, atrial flutter; CI, contraindicated; CNS, central nervous system; F:M, fetal:maternal; IC, intracordal; IM, intramuscular; IV, intravenous; JET, junctional ectopic tachycardia; LQTS, long QT syndrome; M/F, maternal/fetal; N/V, nausea/vomiting; PJRT, permanent junctional reciprocating tachycardia; PO, per os (orally); QTc, corrected QT interval; SVT, supraventricular tachycardia; VT, ventricular tachycardia.