Supraventricular arrhythmia in pregnancy

Abstract

The physiological changes during pregnancy predispose a woman for the development of new-onset or recurrent arrhythmia. Supraventricular arrhythmia is the most common form of arrhythmia during pregnancy and, although often benign in nature, can be concerning. We describe three complex cases of supraventricular arrhythmia during pregnancy and review the currently available literature on the subject. In pregnancies complicated by arrhythmia, a plan for follow-up and both maternal and fetal monitoring during pregnancy, delivery and post partum should be made in a multidisciplinary team. Diagnostic modalities should be used as in non-pregnant women if there is an indication. All antiarrhythmic drugs cross the placenta, but when necessary, medical treatment should be used with consideration to the fetus and the mother's altered pharmacodynamics and kinetics. Electrical cardioversion is safe during pregnancy, and electrophysiological study and catheter ablation can be performed in selected patients, preferably with zero-fluoroscopy technique. Sometimes, delivering the fetus (if viable) is the best therapeutic option. In this review, we provide a framework for the workup and clinical management of supraventricular arrhythmias in pregnant women, including cardiac, obstetric and neonatal perspectives.

Keywords: arrhythmias; atrial fibrillation; atrial flutter; cardiac; pregnancy; supraventricular; tachycardia.

Figure 1

ECG of a woman aged 34 years presenting at 37 weeks of gestation with a regular supraventricular tachycardia of 220 bpm with a retrograde P wave, suggestive of an atrioventricular (nodal) re-entry tachycardia. Hyperthyroidism and an atrioventricular re-entry tachycardia with concealed bypass were later discovered.

Figure 2

Transthoracic echocardiogram and ECG of a woman aged 35 years with Marfan syndrome and a mitral valve bioprosthesis, presenting at 14 weeks of gestation with atrial fibrillation. (A) Transthoracic echo at 20 weeks of gestation showing parasternal and apical view of the bioprosthesis. Continuous wave Doppler showing a mean peak gradient of 7 mm Hg. (B) ECG showing recurrent atrial fibrillation with rapid ventricular response at 37 weeks of gestation. (C) Continuous wave Doppler at 2 months post partum, showing worsening mitral stenosis with a mean PG of 10 mm Hg of the prosthetic valve and tricuspid regurgitation velocity of 2.4 m/s.

Figure 3

ECG and echocardiogram of a woman aged 38 years at 16 weeks of gestation, presenting with atrioventricular (nodal) re-entry tachycardia (AV(N)RT). (A) ECG of a regular supraventricular tachycardia of 205 bpm with an intermediate axis and a narrow QRS complex. A retrograde P wave was observed 120 ms behind the QRS complex, suggestive of an AV(N)RT. (B) Subcostal view of an echocardiogram after an electrophysiological (EP) study with ablation for a left lateral concealed bypass atrioventricular re-entry tachycardia, showing moderate pericardial effusion as complication of the EP study.

Figure 4

Electrophysiological study and ablation in a woman with persisting palpitations post partum. (A) Location of catheters in left anterior oblique (LAO) view. The ablation catheter (*) is positioned at the site of successful ablation of the left lateral concealed bypass. (B) Intracardiac electrograms during RV apical pacing at a cycle length of 600 ms. There is an eccentric retrograde atrial activation during RV pacing with earliest activation at the distal coronary sinus. Note the short local ventricular to atrial interval at the site of successful ablation (ABL 1–2). ABL, ablation catheter; CS, coronary sinus; RF, radiofrequency; RV, right ventricle.

Figure 5

Flow chart of the diagnosis and treatment of supraventricular arrhythmia during pregnancy. *Flecainide is relatively contraindicated in women with structural heart disease, and is also contraindicated in case of atrial flutter due to risk of 1:1 AV conduction. AVNRT, atrioventricular nodal re-entry tachycardia; AVRT, atrioventricular re-entry tachycardia; CTG, cardiotocogram; DOAC, direct oral anticoagulants; EP, electrophysiological; Hb, haemoglobin; Ht, haematocrit; LMWH, low molecular weight heparin; NT-proBNP, N-terminal pro b-type natriuretic peptide; SR, sinus rhythm; SVT, supraventricular tachycardia; VKA, vitamin K antagonist.