How to manage stable ventricular tachycardia (VT) in a pregnant patient?

Management of Stable Ventricular Tachycardia in Pregnancy

Immediate electrical cardioversion is recommended for all sustained VT in pregnant patients, regardless of hemodynamic stability. 1

Acute Management Algorithm

First-Line Treatment: Electrical Cardioversion

• Synchronized cardioversion is the definitive treatment for both stable and unstable sustained VT in pregnancy, with the same energy dosing as non-pregnant patients 1
• Apply electrode pads with the energy trajectory directed away from the uterus 1
• Perform fetal monitoring during cardioversion (if time allows) and immediately post-cardioversion 1
• Cardioversion has been reported safe at all stages of pregnancy 1

Pharmacological Options (If Cardioversion Fails or Is Unavailable)

For sustained, hemodynamically stable, monomorphic VT, the following medications should be considered:

• Intravenous sotalol or procainamide are reasonable second-line options for stable monomorphic VT 1
• Intravenous amiodarone should be considered only for VT that is refractory to electrical cardioversion or not responding to other drugs, despite its fetotoxic effects 1

The ESC guidelines explicitly recommend immediate electrical cardioversion over pharmacological therapy as the primary approach, even in stable VT, which differs from non-pregnant management where medications might be attempted first 1. This reflects the priority of maternal and fetal safety over avoiding procedural intervention.

Long-Term Management

Oral Antiarrhythmic Therapy

For idiopathic sustained VT requiring chronic suppression:

• Oral metoprolol, propranolol, or verapamil are first-line agents 1
• Oral sotalol, flecainide, or propafenone should be considered if first-line agents fail 1
• Beta-blockers should be used with caution in the first trimester 1

Device Therapy

• ICD implantation is recommended whenever clinically indicated during pregnancy, not delayed until after delivery 1
• If ICD was indicated prior to pregnancy, it should have been implanted before conception 1
• Permanent pacemaker or ICD implantation (preferably single chamber) should be performed with echocardiographic guidance, especially if the fetus is beyond 8 weeks gestation 1

Catheter Ablation

• Catheter ablation may be considered for drug-refractory and poorly tolerated tachycardias during pregnancy 1
• Preferably performed with zero-fluoroscopy technique to minimize fetal radiation exposure 2
• This is reserved for exceptional cases where medical management has failed 1

Special Considerations

Congenital Long QT Syndrome

• Beta-blocking agents are mandatory during pregnancy and postpartum for patients with long QT syndrome, as they provide major benefit in preventing torsade de pointes 1, 3

Critical Pitfalls to Avoid

• Never use atenolol for any arrhythmia in pregnancy due to risk of intrauterine growth retardation 1, 4
• Avoid amiodarone unless all other options have failed, due to significant fetotoxic effects including thyroid dysfunction and growth restriction 1
• Do not delay cardioversion in favor of prolonged medication trials—the guidelines prioritize immediate cardioversion even for stable VT 1
• Class III drugs should not be used in cases with prolonged QTc 1

Delivery Considerations

• In refractory cases with continued VT despite medical management, delivering the fetus (if viable) may be the best therapeutic option 2, 5
• This requires multidisciplinary planning with cardiology, obstetrics, and neonatology 5

The evidence strongly favors an aggressive approach with electrical cardioversion as first-line therapy for sustained VT in pregnancy, contrasting with the more conservative medication-first approach sometimes used in non-pregnant patients with stable VT 1. This reflects the unique risks pregnancy poses to both mother and fetus from sustained ventricular arrhythmias.