From the Guidelines
Tachycardia in pregnancy should be managed by first determining if it's sinus tachycardia or an arrhythmia requiring treatment, with initial management including positioning, oxygen, and addressing underlying causes, and pharmacological treatment with cardioselective beta-blockers like metoprolol or labetalol, as recommended by the 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia 1. When evaluating tachycardia in pregnancy, it is essential to consider the potential risks and benefits of treatment, as pregnancy may confer an increased susceptibility to arrhythmias, even in the absence of underlying heart disease 1. Some key points to consider in the management of tachycardia in pregnancy include:
- Initial management: positioning the patient on her left side to improve venous return, providing oxygen if needed, and addressing any underlying causes like anemia, dehydration, fever, hyperthyroidism, or anxiety.
- Pharmacological treatment: cardioselective beta-blockers like metoprolol (25-50mg twice daily) or labetalol (100-200mg twice daily) are generally considered safe in pregnancy, as well as calcium channel blockers such as verapamil (120-360mg daily in divided doses) 1.
- Acute management of supraventricular tachycardia: vagal maneuvers can be attempted first, followed by adenosine (6mg IV rapid push, followed by 12mg if needed) if vagal maneuvers fail, as recommended by the ESC guidelines on the management of cardiovascular diseases during pregnancy 1.
- Electrical cardioversion: safe in pregnancy for hemodynamically unstable patients, and should be considered in cases of severe symptoms or hemodynamic compromise, as recommended by the ESC guidelines 1. Close monitoring with serial ECGs and possibly Holter monitoring is recommended, along with multidisciplinary care involving obstetrics and cardiology, to balance maternal benefit against potential fetal risks, with medication doses adjusted as pregnancy progresses due to changing maternal physiology 1.
From the Research
Tachycardia in Pregnancy: Causes and Risks
- Tachycardia in pregnancy is a common complication due to hormonal changes that enhance pre-existing arrhythmias or induce new arrhythmias in the presence of congenital heart defects in pregnant females 2.
- The presence of tachyarrhythmia during pregnancy poses a risk to the mother and fetus, calling for proper treatment with medications 2.
- Maternal tachyarrhythmia can be caused by various factors, including atrioventricular-nodal-reentry tachycardia (AVNRT), which is a form of supraventricular tachycardia (SVT) 3.
Diagnosis and Treatment
- The diagnosis of tachycardia in pregnancy can be challenging, and distinguishing between physiological and pathological causes is crucial 4.
- Treatment of tachyarrhythmias in pregnancy differs very little from a non-pregnant adult, and unstable arrhythmias should follow Resuscitation Council UK guidelines 4.
- Vagal maneuvers, adenosine, and calcium channel blockers are commonly used to treat AVNRT in pregnancy 3.
- Beta-blockers have been evaluated but should not be used routinely due to lower efficacy 3.
- Electrical cardioversion should be utilized for hemodynamically unstable patients 3.
Management and Care
- Pregnant women with pathological arrhythmias need to be cared for under a multidisciplinary team, including obstetricians, obstetric anaesthetists, specialist midwives, cardiologists, and obstetric physicians 4.
- The use of antiarrhythmic drugs in cases of maternal tachyarrhythmia must give due consideration of potential teratogenic side effects 2.
- New techniques, such as cardiac ablation, have also been implemented with minimal or no radiation exposure to the fetus or mother 2.
- Pregnant women with tachyarrhythmia have been successfully treated with little to no impact on the developing fetus as a result of increasing experience with antiarrhythmic drugs and progress of new procedural techniques 2.