From My Mailbox: Catheter Ablation Complication Rate: Compared to What?
Frequently I get emails asking about the complication rate of catheter ablation.
I like the suggestion made by Dr. David Keane of St. Vincent’s University Hospital, Dublin Ireland. Complications from A-Fib ablation should be viewed in perspective, that is, compared to the alternative of a lifetime on antiarrhythmic drugs (AADs).
The following is based on his presentation from the 2014 Boston AF Symposium.
Meta-Analysis: RF Catheter Ablation vs. Antiarrhythmic Drugs
In what may be the first systematic literature review and meta-analysis of clinical studies of Radiofrequency Ablation (RFA) vs. Antiarrhythmic Drugs (AADs), the reviewers looked at studies from 1990 to 2007. [Note: RFA wasn’t in use until the mid-1990s.] Included were sixty-three RFA studies and 34 AAD studies.
RF Ablation: From 1990-2007, the single procedure success rate for Radiofrequency Ablation (RFA) without need of post-op Antiarrhythmic Drug (AAD) therapy was 57% [today’s success rates are in the 70%–85% range], multiple procedure success rates without post-op AADs were 71% [today’s success rates are closer to 90%], and the multiple procedure success rate with post-op AADs was 77%.
AAD Therapy: The success rate for AAD therapy alone was 52%.
Note: The meta-analysis included five AADs: amiodarone, dofetilide, sotalol, flecainide, and propafenone. Amiodarone was the most effective. [Amiodarone is the most toxic and dangerous of the five AADs and is usually prescribed only for short periods of time and under close supervision for bad side effects.]
Adverse Event: side effect or any undesirable experience associated with the use of a medical product in a patient. In the US, adverse events are reported to the FDA.
Side Effects Cause Patients to Stop Taking AADs: Because of adverse events (side effects), 10.4% of patients discontinued taking their AADs, 13.5% discontinued AADs because of treatment failure, and 4.2% just didn’t take the AADs.
The overall discontinuation rate of AADs was almost 30%.
Findings: Efficiency and Complications Rates
Based on the meta-analysis, reviewers found Radiofrequency Ablation (RFA) had a higher efficiency rate and a lower rate of complications than AAD Therapy.
Findings: Adverse Events Ablation vs AAD
More about AAD Therapy adverse events: The overall death rate for AAD therapy was 2.8% (i.e., sudden death 0.6%, treatment-related death 0.5%, non treatment-related death 1.3%). Other adverse events from AAD therapy were:
• CV (cardiovascular) Events 3.7%
• Bradycardia 1.9%
• GI (Gastrointestinal problems) 6.5%
• Neuropathy 5.0%
• Thyroid Dysfunction 3.3%
• Torsades 0.7%
• Q-T prolongation 0.2%
Conclusions from Meta-Analysis
Most adverse events associated with antiarrhythmic drugs (AADs) are life altering and permanent. (For example, bradycardia requires a pacemaker.)
Whereas complications from catheter ablation are generally short term and not permanent. (For example, when tamponade is repaired, the heart usually returns to normal.)
While this meta-analysis covered 1990-2007, based on subsequent research the trends are continuing. In general, it appears it’s safer to have an ablation than to not have one while living a life-time on AAD therapy.
The Full Report: For the full summary of Dr. Keane’s 2014 Symposium presentation, see: Catheter Ablation Complications: In-depth Review and Comparison with Antiarrhythmic Drug Therapy.
What this Means to Patients
If you are age 70 or 80, antiarrhythmic drugs might be a realistic option.
Today’s ‘Guidelines for the Management of Patients with Atrial Fibrillation’ reflect this fact and allow you to select a catheter ablation without having to spend time trying various antiarrhythmic drugs (while your A-Fib may be getting worse).
In general, research shows it’s safer to have an ablation than to not have one (and live a lifetime on AA drug therapy).