Considerations for Patients Undergoing Electrophysiology Study (EPS) with Radiofrequency (RF) Ablation
Radiofrequency catheter ablation is the treatment of choice for most patients with symptomatic arrhythmias that are drug-resistant, when patients cannot tolerate antiarrhythmic medications, or when patients prefer ablation over long-term drug therapy. 1
Indications for RF Ablation
Class I Indications (Strong Recommendations)
- Symptomatic sustained AVNRT that is drug resistant, drug intolerant, or patient preference 2
- Symptomatic AV reentrant tachycardia that is drug resistant, drug intolerant, or patient preference 2
- Atrial fibrillation with rapid ventricular response via accessory pathway that is drug resistant 2
- Atrial tachycardia or flutter that is drug resistant 2
- Sustained monomorphic VT that is drug resistant 2
- Bundle branch reentrant ventricular tachycardia 2
Class II Indications (Reasonable to Consider)
- Sustained AVNRT identified during EP study for another arrhythmia 2
- AV reentrant tachycardia identified during EP study for another arrhythmia 2
- Asymptomatic ventricular pre-excitation affecting livelihood, profession, or public safety 2
- Atrial flutter/tachycardia associated with paroxysmal atrial fibrillation 2
Success Rates and Outcomes
Success rates vary by arrhythmia type and location:
- Accessory pathways: 91% for left free-wall, 87% for septal, and 82% for right free-wall 2
- Overall success rates exceed 95% for most common SVTs 1
- Long-term success in RVOT tachycardia: 95% 3
- Success rates for ARVD patients are lower at 71% 3
Complications to Consider
General Complications (2-3% overall rate) 2, 1
- Death (0.1-0.2%) 2, 1
- Vascular access complications (1%): hematomas, fistulas 2
- Pneumothorax (0.2%) 2
- Cardiac tamponade 2
- Pulmonary or systemic emboli 2
Arrhythmia-Specific Complications
- AV block: 0.1-1.3% (higher with fast pathway ablation at 5.3% vs. slow pathway at 2%) 1
- Bundle branch block: 0.9% for right bundle, 0.3% for left bundle with anteroseptal pathways 2
- Valve damage 2
Risk Factors for Complications
- Older age (significantly higher complication rates in elderly patients: 6.1% vs 2.0% in younger patients) 4
- Presence of systemic disease in elderly patients 4
- Anatomical location of arrhythmia focus (septal pathways carry higher risk of AV block) 2
Pre-Procedure Considerations
Contraindications
- Unstable angina 2
- Bacteremia or septicemia 2
- Acute decompensated heart failure not caused by the arrhythmia 2
- Major bleeding diathesis 2
- Acute lower extremity venous thrombosis (if femoral approach planned) 2
- Inability to receive anticoagulation for AF ablation 1
Patient Selection Factors
- Arrhythmia mechanism (reentrant vs. automatic/triggered) 3
- Structural heart disease (affects success rates and complication risk) 5, 3
- Prior response to antiarrhythmic medications 2
- Patient preference regarding long-term medication vs. ablation 2
Post-Procedure Care
- Anticoagulation for at least 2 months post-ablation for AF 1
- Regular monitoring with ECGs and Holter monitoring 1
- Continued antiarrhythmic therapy may be needed in some patients 5
- Careful follow-up for recurrence (recurrence rates vary: 6% for RVOT, 48% for ARVD) 3
Special Considerations
- For patients with ICDs experiencing inappropriate shocks due to SVT, RF ablation is highly effective (95% reduction in inappropriate therapies) 6
- In patients with hypertrophic cardiomyopathy and AF, ablation can be effective (64% success rate) with marked symptomatic improvement 5
- Patients with ARVD have lower success rates and higher recurrence rates than those with RVOT tachycardia 3
Pitfalls to Avoid
- Failing to distinguish between ARVD and RVOT tachycardia (different success rates and approaches) 3
- Underestimating complication risks in elderly patients 4
- Performing AF ablation solely to avoid anticoagulation (Class III harm) 1
- Discontinuing anticoagulation based solely on perceived success of AF ablation 1
- Overlooking the possibility of multiple accessory pathways (present in 6% of WPW patients) 7