Less
is More in Atrial Fibrillation Ablation Trends: Fewer Repeats, Shorter
Procedures, and More Patients.
Bruce A. Koplan, MD, MPH
Cardiac Arrhythmia Service, Division of Cardiovascular Medicine, Brigham
and Women’s Hospital, Boston, Massachusetts
Address for Correspondence
Bruce A. Koplan, MD, MPH
Brigham and Women’s Hospital
75 Francis Street
Boston, MA 02115
Author Disclosures/Conflicts of Interest: None
The incidence of atrial fibrillation (AF) is increasing significantly,
with estimates of 1.2 million new cases in the United States in 2010,
rising to 2.6 million new cases annually in 2030 and a lifetime risk of
1 in 4 individuals.1 The benefits of AF ablation have
been demonstrated in a number of clinical trials2; 3and guidelines increasingly support offering ablation as early line
therapy in appropriately selected patients.4-6 The
combination of rising new AF diagnoses and greater acceptance of AF
ablation in widening demographic groups has led to significant growth of
this procedure. In the setting of this growth, it is important to have a
continual accounting of efficacy and safety as technology and procedural
strategies evolve.
In this issue of the Journal, Kushnir et al. provide a report of
temporal trends in 5,407 first-time AF ablations at a large academic
medical center over a 10 year period (2011-2021).7 The
primary analysis focused on efficacy as measured by time to redo AF
ablation and correlations were made with changes in technology and
ablation strategy. The primary endpoint, time to redo ablation or DCCV,
decreased significantly over time (22% to 14%), and this occurred
despite a doubling of persistent AF (22% to 44% representation) in the
cohort. Additional observations were also made. The Annual AF ablation
volume increased significantly during this time frame
(>135%). The authors also report low major adverse event
rate over time (1.1%) despite an increase in median age and
co-morbidities which may suggest an improvement in safety given the
potential for higher risk of complications in a sicker population. It is
also worth noting that the study population underwent radiofrequency
ablation and it does not appear that any of the patients underwent
cryoablation. Amiodarone was given to approximately 20% of the cohort
throughout the time period, while Dronaderone was given to greater than
60% of the cohort in the earlier years with a significant decrease in
later years.
How do the authors findings compare to previously reported literature?
With regard to the incidence of repeat ablation, Piccini et al
previously reported, in 2012, a repeat ablation incidence of 10.9% at
one year in a cohort of 15,400 Medicare beneficiaries undergoing AF
ablation.8 Assuming a constant annual incidence, the
current, more contemporary contemporary cohort had an improved repeat
ablation rate. The exponential increase in AFib ablation volume over
time is also impressive and is similar to national and international
trends.9
The low rate of major complications reported by the authors appears to
be lower than in previously reported publications. Bohnen, et al.
reported a major complication rate of 5.2% in a 2011 cohort from a
large academic center.10 A later AF ablation cohort
from 2015 reported a decrease to 2.3% in major
complications.11 Although the low adverse event rate
in the current report is impressive, there were some differences in
categorization of complications. The authors considered vascular
complications to be those requiring surgical or catheter-based
intervention. The earlier reports mentioned included additional vascular
access complications such as retroperitoneal bleed requiring transfusion
and extended hospital stay as a major adverse event even in the absence
of procedural intervention, and inclusion of such events may have
increased the reported complication rate. This is especially true
because vascular complications tend to be the most frequent adverse
event in reported previous series whereas in the current study
pericardial effusion was the most common complication reported (0.46%).
What accounts for these improvements in ablation over time? The authors
attribute improved success and efficiency to a multitude of changing
technology and techniques. These include change in mapping technology,
ventilation (jet ventilation), pacing strategy to improve catheter
stability, and high power short duration settings. With regard to jet
ventilation, it is worth noting that some centers have adopted a reduced
tidal volume increased ventilation rate strategy which may be more
simple.12 Furthermore, the authors eliminated stepwise
linear ablation strategies which appears to be consistent with current
trends at many institutions and with large clinical trial data that has
failed to show definitive advantage of additional ablation strategies
beyond PVI in first time ablations13; 14. Further,
Muthalaly, et al also reported a time dependent trend in improved
quality and safety in the setting adoption of forced sensing and
irrigated catheters, and elimination of additional ablation
lines.11 As the authors mention in their discussion,
empiric lines can also promote macro-reentrant arrhythmias and redo
procedures. It would, therefore, seem appropriate for the standard of
care to remain PVI and possibly targeting observed arrhythmias, but not
to include additional empiric lines in first time ablations.
There are some additional limitations that are worth noting. First of
all, the data comes from a high-volume center with experienced
operators. These data may not be as generalizable to other centers. It
may also be difficult to discern to what extent improving technology vs.
improvement in experience was to account for the positive findings. In
addition, use of time to redo ablation or DCCV may underestimate failure
rates compared to an efficacy endpoint such post-procedure EKG and
monitoring data. Given that many studies utilize a low level of AF on
monitoring (e.g. 30s of AF on holter) the success rate would be
perceived as greater in the authors study. It is also possible that some
operators developed a greater appreciation over time of selected
scenarios where repeat ablation or cardioversion was felt to be futile
and some of the instances of “no redo or cardioversion” were from drop
out of rhythm control strategy rather than efficacy. Nonetheless, the
authors study demonstrates improvement from baseline which is relevant.
Furthermore, 30 seconds of AF on a holter may be overly conservative and
less clinically relevant than a longer amount of AF, symptomatic AF, or
time to redo ablation. Also, the data was censored at 3 years. It may be
informative to have longer follow up. While the adverse event rate was
low in the cohort, it is not possible to comment on any decrease over
time as complications data was not available from the first 4 years
(2011-2015). Lastly, the authors conclusions about subcategories of
patients, such as the observation of higher recurrence in amiodarone
treated patients, derives from non-randomized unadjusted data, and
therefore should probably be ignored.
What could these findings lead to? Being able to convey to patients the
sense of a safer, shorter, and more successful procedure is likely to
increasingly favor choosing AF ablation over antiarrhythmic drugs. When
success increases, procedure time decreases, complications decrease,
many centers have developed a same day discharge strategy with excellent
safety and success.15 Throw in the possibility of same
day discharge vs. a multiple night stay for antiarrhythmic drug
initiation and the choice weighs further in favor of ablation.
In summary, the authors provide an excellent perspective on how trends
in AF ablation have evolved in a manner of “Less is More”. Fewer redo
ablations, shorter procedure time, low complication rates and more, and
more patients.
1. Tsao CW, Aday AW, Almarzooq ZI, Anderson CAM, Arora P, Avery CL,
Baker-Smith CM, Beaton AZ, Boehme AK, Buxton AE et al. 2023. Heart
disease and stroke statistics-2023 update: A report from the american
heart association. Circulation.
2. Kirchhof P, Camm AJ, Goette A, Brandes A, Eckardt L, Elvan A, Fetsch
T, van Gelder IC, Haase D, Haegeli LM et al. 2020. Early rhythm-control
therapy in patients with atrial fibrillation. N Engl J Med.
383(14):1305-1316.
3. Marrouche NF, Kheirkhahan M, Brachmann J. 2018. Catheter ablation for
atrial fibrillation with heart failure. N Engl J Med. 379(5):492.
4. January CT, Wann LS, Calkins H, Chen LY, Cigarroa JE, Cleveland JC,
Ellinor PT, Ezekowitz MD, Field ME, Furie KL et al. 2019. 2019
aha/acc/hrs focused update of the 2014 aha/acc/hrs guideline for the
management of patients with atrial fibrillation: A report of the
american college of cardiology/american heart association task force on
clinical practice guidelines and the heart rhythm society. Heart Rhythm.
16(8):e66-e93.
5. Hindricks G, Potpara T, Dagres N, Arbelo E, Bax JJ,
Blomström-Lundqvist C, Boriani G, Castella M, Dan GA, Dilaveris PE et
al. 2021. 2020 esc guidelines for the diagnosis and management of atrial
fibrillation developed in collaboration with the european association
for cardio-thoracic surgery (eacts): The task force for the diagnosis
and management of atrial fibrillation of the european society of
cardiology (esc) developed with the special contribution of the european
heart rhythm association (ehra) of the esc. Eur Heart J. 42(5):373-498.
6. Calkins H, Hindricks G, Cappato R, Kim YH, Saad EB, Aguinaga L, Akar
JG, Badhwar V, Brugada J, Camm J et al. 2017. 2017
hrs/ehra/ecas/aphrs/solaece expert consensus statement on catheter and
surgical ablation of atrial fibrillation. Heart Rhythm.
14(10):e275-e444.
7. Kushnir A, Barbhaiaya C, Aizer A, Jankelson L, Holmes D, Knotts R,
Park D, Spinelli M, Bernstein S, Chinitz L. 2023. Temporal trends in
atrial fibrillation ablation procedures at an academic medical center:
2011 – 2021 JCE. x(x):x.
8. Piccini JP, Sinner MF, Greiner MA, Hammill BG, Fontes JD, Daubert JP,
Ellinor PT, Hernandez AF, Walkey AJ, Heckbert SR et al. 2012. Outcomes
of medicare beneficiaries undergoing catheter ablation for atrial
fibrillation. Circulation. 126(18):2200-2207.
9. Kneeland PP, Fang MC. 2009. Trends in catheter ablation for atrial
fibrillation in the united states. J Hosp Med. 4(7):E1-5.
10. Bohnen M, Stevenson WG, Tedrow UB, Michaud GF, John RM, Epstein LM,
Albert CM, Koplan BA. 2011. Incidence and predictors of major
complications from contemporary catheter ablation to treat cardiac
arrhythmias. Heart Rhythm. 8(11):1661-1666.
11. Muthalaly RG, John RM, Schaeffer B, Tanigawa S, Nakamura T, Kapur S,
Zei PC, Epstein LM, Tedrow UB, Michaud GF et al. 2018. Temporal trends
in safety and complication rates of catheter ablation for atrial
fibrillation. J Cardiovasc Electrophysiol. 29(6):854-860.
12. Osorio J, Varley A, Kreidieh O, Godfrey B, Schrappe G, Rajendra A,
Silverstein J, Romero J, Rodriguez D, Morales G et al. 2022.
High-frequency, low-tidal-volume mechanical ventilation safely improves
catheter stability and procedural efficiency during radiofrequency
ablation of atrial fibrillation. Circ Arrhythm Electrophysiol.
15(4):e010722.
13. Verma A, Jiang CY, Betts TR, Chen J, Deisenhofer I, Mantovan R,
Macle L, Morillo CA, Haverkamp W, Weerasooriya R et al. 2015. Approaches
to catheter ablation for persistent atrial fibrillation. N Engl J Med.
372(19):1812-1822.
14. Marrouche NF, Wazni O, McGann C, Greene T, Dean JM, Dagher L,
Kholmovski E, Mansour M, Marchlinski F, Wilber D et al. 2022. Effect of
mri-guided fibrosis ablation vs conventional catheter ablation on atrial
arrhythmia recurrence in patients with persistent atrial fibrillation:
The decaaf ii randomized clinical trial. JAMA. 327(23):2296-2305.
15. Field ME, Goldstein L, Corriveau K, Khanna R, Fan X, Gold MR. 2021.
Same-day discharge after catheter ablation in patients with atrial
fibrillation in a large nationwide administrative claims database. J
Cardiovasc Electrophysiol. 32(9):2432-2440.