The development of catheter ablation for the treatment of patients with cardiac arrhythmias represents one of the seminal achievements in the history of heart disease therapy. The first catheter-based approach for interventional arrhythmia treatment was described in 1982 when Mel Scheinman and Fred Morady of the University of California San Francisco reported a method called “catheter fulguration” for creating heart block with an endocardial catheter. The precise location of the His bundle was first determined by endocardial mapping of the atrial septum just above the tricuspid valve annulus. After it was located, an electrical shock was delivered through the catheter to create permanent heart block, and a permanent ventricular pacemaker was then implanted.
Elective heart block by the catheter fulguration technique was used to treat patients with various intractable supraventricular tachyarrhythmias throughout the 1980s. The objective of elective His bundle ablation was not to ablate the atrial fibrillation (AF) but rather to confine it to the atria and protect the ventricles from the irregularly irregular rhythm associated with AF (see Chapter 11 ). Sealy and Gallagher had been performing elective His bundle ablation that required open-heart surgery for almost 10 years before Scheinman’s catheter fulguration technique was introduced. However, the far less invasive catheter technique proved to be as successful in creating heart block as the surgical approach had been, so the latter receded into history. After radiofrequency (RF) catheters became available in the late 1980s, the catheter fulguration technique was abandoned.
Before the availability of RF catheters, successful surgical procedures had been developed for the treatment of Wolff-Parkinson-White syndrome (1968), ischemic ventricular tachycardia (1978), , nonischemic ventricular tachycardia (1979), automatic atrial tachycardias (1980), atrioventricular node reentry tachycardia (1982), and AF (1987). However, the ability to perform RF catheter ablation in the early 1990s quickly replaced all of these surgical approaches except the Maze procedure for the treatment of patients with AF.
Multiple attempts at creating a Maze-like pattern of atrial lesions with an endocardial RF catheter were unsuccessful, but in 1998, Michel Haissaguerre and Pierre Jais reported that most episodes of AF were induced by pulmonary vein (PV) triggers and that the frequency of paroxysmal AF (PAF) episodes could be decreased, or even abolished, by isolating the triggers to the PVs. This seminal article initiated the era of catheter ablation for AF that has dominated its interventional treatment to the present day.
Impact of Atrial Fibrillation Type on the Results of Catheter Ablation
After Haissaguerre and coworkers’ 1998 article, pulmonary vein isolation (PVI) with RF catheters proved to be quite successful for the treatment of patients with PAF. In their original article, Haissaguerre et al. reported a success rate with PVI for PAF of 62%.Thousands of publications on the results of catheter ablation for AF have appeared in the literature since that time. In 2023, Roger Winkle and his associates in Redwood City and Palo Alto, California, published a remarkable and unique article reporting their personal series of 5200 patients who underwent 7145 catheter ablation procedures over a period of two decades (2003–2023). To include the most contemporary ablation devices and techniques, they divided the years into three treatment eras. Catheter ablation was performed in 101 patients using solid big-tip catheters from 2003 to 2005. From 2005 to 2016, 2143 patients had ablation with open irrigated-tip catheters, and from 2016 to 2021, 2956 patients were ablated using contact force catheters. There was some overlap in the types of catheters used in the last two eras. Winkle et al. also reported the patient results at 5, 10, and 16 years according to whether the patient had PAF, persistent AF, or long-standing persistent AF (LSpAF). Their report demonstrated a significant difference in the results of catheter ablation depending primarily on the type of AF being treated ( Fig. 31.1 ).
Sixteen-year success rates of catheter ablation for paroxysmal atrial fibrillation (AF), persistent AF, and long-standing persistent AF (LSpAF) in 5200 patients. At 16 years, the success rates were 63% for paroxysmal AF, 40% for persistent AF, and 20% for LSpAF.
(Modified and reproduced from Winkle RA, Mead RH, Engel G, et al. Very long term outcomes of atrial fibrillation ablation. Heart Rhythm. 2023;20:680–688.)
Catheter Ablation for Paroxysmal Atrial Fibrillation
Winkle et al.’s article documented that the AF-freedom rates after their final catheter ablation for PAF at 5, 10, and 16 years were 80%, 73%, and 63%, respectively. In 2014, Takigawa and colleagues reported a success rate of 75% at 9 years in 1220 patients with PAF who had catheter PVI in addition to “focal ablation for nonpulmonary vein foci.” It is interesting that Winkle and colleagues’ 9-year success rate of 75% for patients with PAF was identical to that of Takigawa and colleagues ( Fig. 31.2 ). The fact that these two large studies, one with 5200 patients and another with 1220 patients, had identical 9-year success rates supports the validity of the subsequent 16-year results reported by Winkle and coworkers.
Winkle et al. and Takigawa et al.’s catheter ablation success rates at 9 years for paroxysmal atrial fibrillation (AF) were identical (75%). Winkle et al.’s patients went on to have a 63% success rate at 16 years.
(Modified and reproduced from Winkle RA, Mead RH, Engel G, et al. Very long term outcomes of atrial fibrillation ablation. Heart Rhythm. 2023;20:680–688 and Takigawa M, Takahashi A, Kuwahara T, et al. Long-term follow-up after catheter ablation of paroxysmal atrial fibrillation. Circ Arrhythm Elecctrophysiol. 2014;7:267–273).
Catheter Ablation for Persistent Atrial Fibrillation
Because of the rather arbitrary nature of the classification of AF (see Chapter 52 ), reports on the treatment of persistent AF often include LSpAF, making it difficult to determine the results of catheter ablation specifically for patients with persistent AF. Thus there is a paucity of information on the results of catheter ablation specifically for those with persistent AF, especially at 5 years. Fortunately, in 2015, a group of three centers in Germany reported a 56% success rate at 5 years for multiple catheter ablations performed solely for persistent AF in 549 patients. In Winkle and colleagues’ report, the 5-year success rate for the catheter ablation of persistent AF was 60%, only 4% different from the German centers’ results ( Fig. 31.3 ).
Winkle et al. and Takigawa et al.’s catheter ablation success rates at 5 years for persistent atrial fibrillation (AF) were 60% and 56%, respectively. Winkle’s patients went on to have a 40% success rate at 16 years.
(Modified and reproduced from Winkle RA, Mead RH, Engel G, et al. Very long term outcomes of atrial fibrillation ablation. Heart Rhythm. 2023;20:680–688 and Schreiber D, Rostock TR, Frolich M, et al. Five-year follow-up after catheter ablation of persistent atrial fibrillation using the stepwise approach and prognostic factors for success. Circ Arrhythm Elecctrophysiol. 2015;8:308–317).
Catheter Ablation for Long-Standing Persistent Atrial Fibrillation
The most important previous study evaluating the effectiveness of catheter ablation for LSpAF was the 2012 Hamburg Study. That landmark study showed that the 5-year success rate after a single catheter ablation for LSpAF was only 20%, but that it increased to 45% after multiple catheter ablations. Winkle et al.’s study showed an identical 45% 5-year success rate for the catheter ablation of LSpAF ( Fig. 31.4 ), again validating the data reported by Winkle et al. at 10 and 16 years after the last catheter ablation.
Winkle et al. and the Hamburg Study’s catheter ablation success rates at 5 years for long-standing persistent atrial fibrillation (AF) were identical (45%). Winkle et al.’s patients went on to have a 20% success rate at 16 years.
(Modified and from Winkle RA, Mead RH, Engel G, et al. Very long term outcomes of atrial fibrillation ablation. Heart Rhythm. 2023;20:680–688 and Tilz RR, Rillig A, Thum et al. Catheter ablation of long-standing persistent atrial fibrillation: 5-year outcomes of the Hamburg Sequential Ablation Strategy . J Am Coll Cardiol. 2012;60(19):1921–1929.)
Catheter Ablation for All Patients With Atrial Fibrillation
Winkle et al. reported that success rates for catheter ablation improved over the entire study period in the patient groups with PAF and persistent AF, but they did not improve in patients with LSpAF. The overall success rates for catheter ablation in all patients in the study (combined PAF, persistent AF, and LSpAF) at 5 years, 10 years, and 16 years were 65%, 58%, and 47%, respectively. The 5-year success rate of 65% was the same as the 5-year overall success rate reported in the 2020 randomized CABANA trial (64%) ( Fig. 31.5 ). Again, this documents that Winkle et al.’s data were consistent with previously reported trials and that their 10-year and 16-year data are reliable indicators of the overall long-term effectiveness of catheter ablation for AF.
