What treatment is recommended for a Brugada (Brugada syndrome) patient with slow ventricular tachycardias (VTs)?

Treatment for Brugada Syndrome Patients with Slow Ventricular Tachycardias

For Brugada syndrome patients with slow ventricular tachycardias, quinidine should be considered as the first-line pharmacological therapy, with ICD implantation recommended for those with documented spontaneous sustained VT or history of cardiac arrest. 1, 2

Risk Stratification and Initial Management

The management approach for Brugada syndrome patients with ventricular tachycardias depends on risk stratification:

High-Risk Patients (Require ICD)

• Survivors of cardiac arrest
• Patients with documented spontaneous sustained VT
• Patients with spontaneous type 1 ECG pattern and history of syncope

For these patients:

• ICD implantation is a Class I recommendation 1, 2
• Quinidine should be added as adjunctive therapy to prevent recurrent arrhythmias 2

Medium-Risk Patients

• Those with spontaneous type 1 ECG pattern who are asymptomatic
• Those who develop VF during programmed ventricular stimulation

For these patients:

• ICD implantation may be considered (Class IIb) 1
• Quinidine may be used as an alternative when ICD is contraindicated or refused 1, 2

Pharmacological Management for Slow VTs

First-Line Therapy: Quinidine

• Quinidine is the most effective pharmacological agent for Brugada syndrome patients with VT 1, 2
• It has been shown to be effective with no deaths reported over an average 9-year follow-up period 2
• Quinidine is particularly indicated for:
  • Patients who qualify for an ICD but have contraindications or refuse it
  • Patients requiring treatment for supraventricular arrhythmias
  • Patients experiencing electrical storms or repeated appropriate ICD shocks

Acute Management of Electrical Storms

• Isoproterenol is recommended for acute management of electrical storms or repetitive VT episodes 1, 3
• Administration protocol:
  • Initial bolus injection (1-2 μg)
  • Followed by continuous infusion (0.15 μg/min)
  • Duration: typically 1-3 days 3
• Isoproterenol suppresses arrhythmic storms by:
  • Decreasing ST-elevation in right precordial leads
  • Shortening RR interval initially
  • Preventing induction of VF in approximately 80% of patients 4

Additional Management Considerations

Catheter Ablation

• May be considered in patients with history of electrical storms or repeated appropriate ICD shocks (Class IIb) 1
• Ablation of abnormal epicardial late activation areas in the right ventricle can suppress recurrent ventricular arrhythmias 2

Important Lifestyle Modifications

• Avoid medications that can induce ST-segment elevation (check www.brugadadrugs.org)
• Avoid excessive alcohol intake and large meals
• Promptly treat fever with antipyretic drugs 1, 2
• Avoid beta-blockers as they can be potentially harmful in Brugada syndrome 2
  • Note: This is in contrast to their beneficial use in other channelopathies

Treatment Algorithm for Slow VTs in Brugada Syndrome

1. Risk assessment: Determine if patient is high-risk (cardiac arrest survivor, documented spontaneous VT)
2. For high-risk patients: ICD implantation + quinidine
3. For electrical storms: Immediate isoproterenol infusion followed by oral quinidine
4. For patients who cannot receive or refuse ICD: Quinidine as primary therapy
5. For recurrent VT despite medication: Consider catheter ablation

Pitfalls and Caveats

• Beta-blockers worsen outcomes in Brugada syndrome and should be avoided, unlike in other cardiac conditions 2
• Propranolol has been shown to aggravate VF and accelerate dominant frequency 4
• While quinidine is effective, approximately 38% of patients may experience side effects 2
• Fever can acutely increase the risk of cardiac arrest in Brugada syndrome patients and should be treated promptly 2
• Even asymptomatic Brugada syndrome patients remain at significant risk of arrhythmic events (annual incidence of 0.5%) 2