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.
But if you are younger, it’s inconceivable that you would spend the rest of your life taking AADs. In addition to not working well or losing their effectiveness over time, they can have bad, cumulative side effects as described above.
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).