24/04/2024
🔴 Pregnancy and Arrhythmia
🫀Pre-conception counseling is a shared decision making process; include obstetrics and maternal-fetal medicine colleagues in challenging cases.
🫀Have a high sense of urgency for acute arrhythmias in pregnancy due to risk of impaired fetal perfusion. Goals of acute arrhythmic management should include rapid treatment while avoiding hypotension.
🫀In scenarios when beta blockers are indicated, metoprolol and propranolol are first choice. Avoid atenolol as this drug has the highest risk of fetal bradycardia and intra-uterine growth retardation in the class.
🫀Lidocaine or procainamide should be first line for ventricular arrhythmias in pregnancy. Amiodarone is potentially teratogenic and should not be used in pregnant patients unless all other options have been exhausted.
🫀What are the expected electrophysiologic changes associated with pregnancy?
👉Increase in resting heart rate which peaks in third trimester
👉PR shortening
👉ECG axis shift leftward and upward
👉Non-specific ST and T wave changes.
These changes, along with increased cardiac output and volume with increased stretch in all chambers, increase the risk of re-entrant arrhythmias in those who are predisposed.
↑ atrial volume -> ↑ stretch -> ↑ ectopy -> ↑ risk for re-entrant arrhythmias
🫀What is the management of SVT in pregnancy?
👉Consider the increased risk of tachyarrhythmias in pregnancy:
👉Typically benign arrhythmias can lead to more rapid decompensation in mother due to increased baseline cardiac output.
👉Typically benign arrhythmias can lead to rapid danger to the fetus due to maternal hypotension and shortened diastolic filling time, both of which contribute to impaired fetal perfusion.
👉Treatment algorithm is identical to that of non-pregnant patients
💥Attempt vagal maneuvers
💥Adenosine is safe
💥Cardioversion is safe: monitor the fetus during and after cardioversion
💥In stable arrhythmias, choose nodal blocking agents with the best safety profile: metoprolol, propranolol, and verapamil.
🫀Evaluation of the pregnant patient with new onset SVT
👉Have a high index of suspicion for underlying structural heart disease such as peripartum cardiomyopathy in a pregnant women with new diagnosis of SVT – presence of structural heart disease significantly increases the risk of maternal morbidity and mortality.
👉Pregnancy can be the first presentation of inherited arrhythmia syndromes that commonly present in young adults such as WPW, Brugada Syndrome, Catecholaminergic Polymorphic VT (CPVT), Long QT Syndrome (LQTS), Arrhythmogenic Right Ventricular Cardiomyopathy / Dysplasia (ARVC/D), and Hypertrophic Cardiomyopathy (HCM).
🫀What are some special considerations for acute management of VT in pregnancy?
👉Cardioversion is safe.
👉First line pharmacologic therapy: lidocaine or procainamide
👉Lidocaine has been associated fetal bradycardia but has been used safely without reported teratogenic effect
👉Brugada syndrome: consider quinidine in Brugada syndrome
👉Fascicular VT: use verapamil
👉Only use amiodarone if absolutely necessary, and after the first trimester
🫀What is the approach to chronic arrhythmia management in pregnancy?
👉Preferred rate control agents:
Metoprolol
Propranolol
Digoxin
Verapamil
👉AVOID: atenolol (increased risk of fetal bradycardia and intrauterine growth restriction; note that this risk is present with all beta blockers*)
👉Preferred rhythm control agents:
Flecainide (if no structural heart disease)
Propafenone (if no structural heart disease)
Sotalol
Lidocaine
Procainamide
Quinidine
👉AVOID: amiodarone; use only in a patient with refractory unstable arrhythmias after the first trimester (due to fetal thyroid and neurodevelopmental issues)
👉AVOID: dronedarone; Category X in pregnancy
🫀Catheter ablation in the pregnant patient
👉Best delayed until late in pregnancy or after delivery
👉Maternal-fetal medicine colleagues should be involved in procedural planning
👉Minimize fluoroscopic time
👉Shield the pelvis during fluoroscopy and use electroanatomic mapping
🫀*Surveillance for pregnant patients on beta blockers:
👉Serial growth ultrasounds in the third trimester
👉Antenatal testing of for bradycardia and hypoglycemia
👉Postnatal monitoring for:
Bradycardia
Apnea
Growth retardation
🫀What is the approach to antiarrhythmic therapy in the breastfeeding patient?
👉All antiarrhythmic drugs are passed into breast milk
👉Preferred rate control agents: metoprolol, propranolol (watch for fetal bradycardia)
👉Rhythm control agents: weigh risks and benefits; read dosing adjustments on prescribing instructions carefully
AVOID: atenolol
AVOID amiodarone
AVOID: dronedarone
🫀What is the approach to anticoagulation in pregnancy and breastfeeding?
👉Use the CHAD2S2-VASc score to estimate stroke risk for pregnant patients with AF and AFL.
👉Risk of stroke with AF and AFL in pregnancy are uncertain, as women of childbearing age were minimally represented in large studies evaluating prophylactic antithrombotic drug treatment.
👉Low molecular weight heparin is preferred in the first trimester and around the time of delivery.
👉Warfarin should be avoided during the first trimester (especially at doses >5 mg daily), but may be used in the second and beginning of the third trimester.
Avoid DOACs
👉During Breast-feeding: Use warfarin or LMWH
AVOID: DOACs may be excreted in breast milk and should not be used during breast feeding.
🫀 What is the approach to specific arrhythmic syndromes?
👉AVNRT: recommend catheter ablation prior to conception if prior diagnosis. Manage acute events if they occur during pregnancy.
👉WPW: recommend catheter ablation prior to conception if prior diagnosis. Use procainamide for acute arrhythmic events and avoid nodal blocking agents.
👉LQTS:recommend beta blockers (metoprolol or propranolol) through pregnancy and at least through the post -partum period
👉CPVT: recommend beta blockers (metoprolol or propranolol) through pregnancy and at least through the post-partum period
🫀What is the approach to management of cardiac arrest in the pregnant patient?
👉ACLS should be performed per ACLS guidelines, including chest compressions and defibrillation.
👉Positioning: aim to avoid IVC compression and impaired venous return to the heart in the supine pregnant patient.
👉Patients with a pulse: left lateral decubitus
No pulse: Manually displace the uterus to the left
👉All patients: place IVs above the diaphragm
Be prepared for difficult airway in mother due to airway edema Call OB and neonatal teams immediately to determine need for emergency C-section if no ROSC within the first several minutes.
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 supra...
