University of Groningen
Ablation of atrial fibrillation
de Maat, Gijs Eduard
IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from
it. Please check the document version below.
Document Version
Publisher's PDF, also known as Version of record
Publication date:
2018
Link to publication in University of Groningen/UMCG research database
Citation for published version (APA):
de Maat, G. E. (2018). Ablation of atrial fibrillation: Moving to a heart team approach. Rijksuniversiteit
Groningen.
Copyright
Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons).
Take-down policy
If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum.
Chap
ter 1
GEnERAl InTRoDuCTIon
Background
Atrial fibrillation (AF) has a major impact on health care in the Western population and is
associated with stroke, heart failure and death.(1-3) Estimations show that worldwide 33.5
million individuals suffer from AF and that there are about 5 million new cases each year.
(4) AF increases in frequency with aging and typically occurs in patients with associated
comorbidities. The most common associated comorbidities are hypertension, coronary
artery disease, valvular disease, hyperthyroidism, heart failure, sleep apnea, obesity and
autonomic dysfunction(5). AF causes a significant burden on the patient and also on the
healthcare system resources. Five patterns of AF can be identified; first diagnosed AF
(AF that has not been diagnosed before irrespective of the duration), paroxysmal
(self-terminating within 7 days), persistent (lasts > 7 days), long-standing persistent (continuous
for >12 months when rhythm control strategy is adopted) and permanent (AF accepted
by the patient and physician)(5). Episodes that are cardioverted within 7 days should be
considered paroxysmal. The definition of permanent AF is that the patient and physician
accept the arrhythmia, and further rhythm control strategy is abandoned(5).
The exact mechanism of AF is not completely understood and may differ per patient.
One or multiple triggers, often caused by foci from the pulmonary veins, initiate AF. It
provokes a shortening of the atrial effective refractory period immediately after start of
AF. Further, and more importantly, AF and the associated comorbidities induce a slow
process of structural remodeling including fibrosis, inflammation, and fatty infiltration.
Structural remodeling results in electrical dissociation between muscle bundles and local
conduction heterogeneities(6), favouring re-entry and perpetuation of the arrhythmia(7).
In many patients, the structural remodeling process occurs before the onset of AF(8). As
the substrate remodels over time, AF is less likely to terminate spontaneously and
treat-ment to maintain sinus rhythm becomes more challenging (figure 1). Therefore, early
diagnosis and early aggressive treatment is important to reduce the AF burden(9). This
arrhythmia is associated with impaired quality of life, stroke and heart failure and
mortal-ity(10). Studies have shown that rate control strategy is non-inferior to rhythm control,
and that rhythm control is only indicated for reduction of symptoms, not for improvement
of survival(11,12). According to the European Society of Cardiology guidelines,
phar-macological rhythm-control therapy is recommended for symptomatic AF patients(13).
However, antiarrhythmic drugs (AAD) with or without cardioversion are only moderately
effective maintaining sinus rhythm and AAD have known adverse effects(11,12).
Risk factor management and life style changes
There is growing evidence of associations between the presence of modifiable risk factors
and the risk of developing AF. In order to decrease the healthcare burden of AF-associated
co-morbiditi es it is essenti al to aggressively address risk factors such as hypertension,
diabetes mellitus, obesity, smoking and alcohol consumpti on(14). Their management is
oft en challenging in the clinical practi ce, in parti cular obesity. It is well known that obesity
is an independent risk factor for the development and perpetuati on of AF(15), and that
it negati vely infl uences the success of ablati on(16,17). A recent study compared acti ve
weight management in combinati on with aggressive risk factor management to general
lifestyle advice. Results showed that weight reducti on with intensive risk factor
manage-ment causes a signifi cant reducti on in AF symptom burden and severity(18). Furthermore,
aggressive risk factor management improves long-term outcomes of AF ablati on(17). If this
weight loss is sustained at long-term follow-up, reducti on of AF burden and maintenance
of sinus rhythm are signifi cantly higher compared to pati ents with weight fl uctuati on(19).
For AF pati ents, cardiac rehabilitati on programs focused on risk factor reducti on and life
style management are an opti on following AF ablati on and should be considered before
invasive treatment strategies are performed(14). The feasibility, eff ect and economic value
of these programs are sti ll to be thoroughly investi gated in large clinical trials.
Target-ing the specifi c individualized substrate must be accompanied by aggressive risk factor
management and multi disciplinary chronic care to improve outcomes(20).
Af symptoms
Two-third of AF pati ents are symptomati c(10). Typical symptoms are palpitati ons, fati gue,
weakness, dizziness, reduced exercise capacity, or dyspnea. More severe symptoms
in-clude dyspnea at rest, angina, presyncope, or infrequently, syncope. Also, some pati ents
present with an thromboembolic event. Provocati ve factors can be rest, sleeping, eati ng
or alcohol (vagal AF) but AF may also be triggered by exercise or emoti ons. To quanti fy
symptom severity, a simple symptom score has been developed by the European Heart
Rhythm Associati on (EHRA-score) classifying AF-related symptoms(21).
figure 1. Importance of triggers and substrate in AF progression
Trigger AF progression Substrate Im po rt an ce
Chap
ter 1
Indications for Af ablation
Patients with highly symptomatic, recurrent and AAD resistant AF are recommended to
undergo AF ablation(5). Catheter ablation can be effective as a rhythm control instrument
in patients with paroxysmal and short-standing persistent AF. For more persistent forms of
AF, refractory to catheter ablation or as concomitant procedure, AF surgery can be
consid-ered. In the following section, different invasive rhythm control treatment strategies will
be introduced.
MAZE surgery
The first successful surgical treatment of AF was performed by Dr. Cox in 1987 with the
Maze lesion set(22). The objective of the Maze procedure was to preclude the ability of
the atria to fibrillate, using lesions to prevent formation of macro-reentrant circuits. The
lesions entail pulmonary vein isolation (PVI), a right atrial set (e.g. ablation lines up to
superior vena cava and down to inferior vena cava across the right atrial free wall
to-wards the atrioventricular groove) and a left atrial set (e.g. closure of appendage and
ablation line across the floor of the left atrium towards the orifice of left inferior PV).
This procedure is performed either through a median sternotomy or a minimal-invasive
thoracotomy, both requiring cardiopulmonary bypass. Long-term results of the Maze-III
operation have been reported to be excellent, with freedom from symptomatic AF up
to 90% at 10-year(23-25). This procedure is complex, technically demanding, requires
cardiopulmonary bypass and median sternotomy. This, accompanied by adverse events,
significantly limited the popularity and general applicability. The Cox-Maze procedure has
been modified over time, in 2004 the group of Damiano replaced most of the original
inci-sions with bipolar radiofrequency and cryothermy (Cox-Maze IV) (figure 2). This way,
sur-figure 2. Modified Cox-Maze IV lesion set
LAA RAA IVC SVC MV TV PV
Cox-Maze IV lesion set using a bipolar radiofrequency clamp. IVC= Inferior Vena Cava, LAA= Left atrial append-age, PV= Pulmonary Veins, MV= Mitral Valve, TV = Tricuspid Valve, SVC = Superior Vena Cava
geons are enabled to perform this procedure through minimally invasive approach whilst
maintaining its efficacy(26). The results are still superior to catheter ablation, especially
for more advanced AF types(27). The Maze procedure can be performed as a stand-alone
procedure in specialized centers, but is nowadays more often used concomitant to (mitral)
valve surgery(28,29).
Transcatheter PVI using radiofrequency
Ever since the important discovery that AF can be triggered from rapidly firing foci situated
in the muscular sleeves of the pulmonary veins (30), techniques were developed to create
electrophysiological blockage of these triggers (figure 3) (31). Nowadays, transcatheter
PVI using radiofrequency is a widespread and well-established technique to prevent
re-currence of symptomatic AF(1,2). Two major randomized trials (MANTRA-PAF, RAAFT-2)
proved the superiority of catheter ablation over AADs(32,33). Outcome of transcatheter
ablation is influenced by severity of structural heart disease. For paroxysmal AF,
transcath-eter PVI has a wide range of reported efficacy (up to 70%) at 1-year follow-up(34). In
ap-proximately one-third of the patients multiple transcatheter ablations are necessary(35).
Technical difficulty of achieving transmural lesions and complete electrical isolation causes
re-conduction to occur in 29% of all patients(36). Complications of transcatheter ablation
are reported in up to 6%(35). Recent studies have shown hampered long-term results of
transcatheter PVI using radiofrequency (RF)(37,38). In order to improve results of
trans-catheter PVI alternative treatment options have been introduced. The new generation of
figure 3. Minimally invasive left atrial ablation methods
Transcatheter RF PVI Transcatheter cryo-balloon PVI
Thoracoscopic PVI Thoracoscopic PVI + box lesion set
Transcatheter radiofrequency point-by-point wide circumferential ablation, Transcatheter cryo-balloon PVI, Thoracoscopic bipolar radiofrequency PVI and Thoracoscopic bipolar radiofrequency PVI with a box lesion set created with a linear bipolar ablation pen. RF= radiofrequency, PVI = Pulmonary vein isolation
Chap
ter 1
RF catheters fitted with pressure sensors, have shown improved outcome. For patients
with persistent and long-standing persistent AF current ablation guidelines promote more
extensive ablation beyond just the PVI(13). These lines can entail a left atrial roofline and
mitral isthmus line. However, the recent STAR-AF 2 trial proved no beneficial effect of
additional ablation lines(39).
Cryoballoon PVI
In recent years, several trials have proven safety and efficacy of the cryoballoon
PVI(40-42). Especially with the second-generation balloon, promising results have been achieved
mostly in paroxysmal AF patients(43). The cryoballoon delivers a circumferential lesion at
the anthrum of the pulmonary vein (figure 3), therefore reducing incidence of conduction
gaps, which are seen in transcatheter point-to-point RF ablation. Also, this technique
dras-tically reduces procedural time. The major drawback of this method is the risk of creating a
phrenic nerve lesion. The occurrence of phrenic nerve lesions has been reported in 5% up
to 11% of patients(42,43). As also seen in transcatheter radiofrequency PVI, the
percent-age of patients who require re-interventions after cryoballoon ablation remain high. The
recent randomized FIRE AND ICE trial demonstrated that for the treatment of paroxysmal
AF, PVI by means of cryoballoon ablation was non-inferior to PVI by radiofrequency
abla-tion in terms of efficacy and safety(44). Long-term outcomes still have to be thoroughly
investigated but in small series of paroxysmal AF patients, 5 year-freedom from AF with a
single cryoballoon PVI has been described at 53%(45).
Thoracoscopic PVI
As an alternative to transcatheter radiofrequency PVI, minimally invasive surgical PVI,
us-ing bipolar RF and other energy sources(46,47) have been developed and are applicable
through a video assisted thoracoscopic approach(46,48,49). The thoracoscopic approach
is less technically demanding than the conventional Maze surgery and delivers a
continu-ous lesion with bipolar RF or other energy sources, without the need for cardiopulmonary
bypass or opening the heart. The bipolar RF clamp uses an algorithm to determine the
impedance feedback, providing a transmural lesion, isolating the pulmonary veins. Usually
this is confirmed by testing of the exit block. Minimally invasive surgery with epicardial
PVI now has a class IIa recommendation (level of evidence B) in the current guidelines for
symptomatic patients with failed transcatheter ablation(5). In 2012, the FAST study was
the first to show that thoracoscopic PVI was superior to transcatheter PVI with regard
to freedom from AF in patients who failed on at least one AAD and prior transcatheter
ablation. However, a higher complication rate was reported in patients who underwent
thoracoscopic PVI(50). Short- and midterm results of thoracoscopic PVI have shown
promising results ranging from 64-90% freedom from AF and AAD after a single
proce-dure(51-58). Few long-term studies show that the thoracoscopic PVI lesions are an
effec-tive, reproducible treatment strategy with maintained efficacy at long-term follow-up(59).
Unfortunately, patient characteristics, ablation platforms and lesion sets differ among the
different available studies, which prohibit thorough comparison of the studies. Also, the
long-term outcomes and effects on cardiac function remain largely unknown.
Hybrid procedure
Some experienced AF ablation centers have pioneered with the combined technique of
epicardial (thoracoscopic PVI with box lesion set) and endocardial ablation during the
same procedure, creating a lesion set similar to that of the Cox-Maze IV(60,61)(figure 4).
The primary advantage of the hybrid technique over thoracoscopic PVI is that the success
of epicardial lesions can be electrophysiologically assessed and if necessary completed.
Second, the transcatheter approach makes it possible to create lesions, which are
oth-erwise not applicable in the minimally invasive setting (e.g. cavotricuspid isthmus line
and completion of lines to the mitral annulus). Especially in patients with persistent and
long-standing persistent AF this technique has shown very high freedom from AF(62,63). It
remains to be investigated if hybrid ablation offers the best of both worlds or offers double
the risk and prolonged procedural times. Furthermore, it remains unclear whether this
type of ablation should take place as a single joint procedure or patients should be offered
a stepwise approach.
figure 4. Hybrid epi- and endocardial lesion set
LAA RAA IVC SVC MV TV PV
Hybrid epi- and endocardial lesion set, red lines depict the thoracoscopically applied lesions, blue lines depict transcatheter lesions. Dotted lines imply optional lesions; the LAA amputation (surgical) and MV isthmus line (transcatheter). IVC= Inferior Vena Cava, LAA= Left atrial appendage, PV= Pulmonary Veins, MV= Mitral Valve, TV = Tricuspid Valve, SVC = Superior Vena Cava
Chap
ter 1
Heart failure
AF and heart failure can cause and exacerbate each other due to structural cardiac
re-modeling, neuro-hormonal mechanisms and asynchronous and/or rate-related reduced
left ventricular function. Especially heart failure with a preserved ejection fraction shares
the same risk factors as AF. Underlying treatment of these conditions could reduce the
progression of both(64). Patients who have the combination of heart failure and AF have
a worse prognosis and higher mortality as compared to patients with heart failure and in
sinus rhythm (65,66). In selected patients, catheter ablation and also MAZE surgery may
be useful to improve left ventricular function(67-69) although details from large
random-ized trials are lacking(70,71).
stroke
One of the major threats caused by AF is stroke(3). Due to AF, stasis of blood in the
left atrium and the left atrial appendage (LAA) occurs and thereby exposes patients to
increased risk of clotting and subsequent thrombo-embolisms. To evaluate the risk for
stroke in AF patients, the CHA
2DS
2-VASc score is used. There is very strong evidence that
patients with a CHA
2DS
2-VASc score ≥2 in male and ≥3 in female patients benefit from
oral anticoagulation (OAC). In patients with a moderate to high risk of thrombo-embolic
events, OAC therapy has proven to significantly reduce the incidence of stroke(72,73). In
addition to traditional vitamin K antagonists, in recent years several non-vitamin K oral
anticoagulants (NOACs) have been introduced. The latest guidelines recommend using
NOACs in preference over vitamin K antagonist for all patients eligible for NOACs(5).
Al-though effective rhythm control is important, even in patients with successful AF ablation,
abolishment of AF does not prevent stroke in the future(74).
The left atrial appendage
It is still discussed whether thrombi originating from the LAA are a major source of stroke
in AF(75). One of the supposed advantages of the surgical approach is that the LAA can be
excluded to reduce stroke risk(76). The surgical approach offers the unique opportunity to
amputate, clip or suture this appendage. However, the beneficial effect on morbidity and
mortality is yet to be demonstrated(77). There is evidence that the left atrial appendage
proves a challenge to close completely, and incomplete closure or amputation may cause
a larger risk for thrombo-embolic events(78,79). Nevertheless, at present, the LAA is
am-putated or closed by a clip on a large scale in stand-alone and concomitant AF surgery(77).
Besides surgical techniques, transcatheter devices have been developed to occlude the
appendage and eliminate stroke risk. Up to date, there is no clear proven beneficial
ef-fect of these techniques compared to OAC(80). Furthermore, the long-term efef-fect of LAA
exclusion on cardiac function is still unknown.
Aims
This thesis aims to investigate the results of different treatment strategies for highly
symp-tomatic, drug resistant AF. In chapter 2 we assess the results of transcatheter RF PVI and
the effect of obesity on long-term outcomes. In chapter 3, we illustrate the relationship of
overweight and symptomatic AF recurrences and stress the importance of weight
counsel-ing, especially before considering invasive treatment modalities. The first three months to
assess success or failure of the ablation are not included. This is known as the “blanking
period”. Chapter 4 questions whether the duration of the blanking period should be
short-ened. The central part of this thesis concerns the role of thoracoscopic PVI for AF ablation.
In chapter 5 we compare the results of thoracoscopic with transcatheter PVI treatment
strategy. chapter 6 shows the mid-term results of thoracoscopic PVI in AF patients without
structural heart disease (lone AF) in a multi-center study. The long-term results of
thora-coscopic PVI for paroxysmal AF in patients without structural heart disease are reported
in chapter 7 In addition to a more effective and durable PVI lesion, the thoracoscopic
approach offers the unique possibility to amputate or exclude the left atrial appendage in
order to reduce stroke risk. However, this procedure may have deleterious effects as well.
Chapter 8 focuses on the effect of concomitant left atrial appendage amputation on LA
function. In chapter 9, right ventricular function is monitored in patients who underwent
thoracoscopic PVI and this is compared to patients who underwent cryoballoon PVI. In
chapter 10, pathophysiologic aspects of AF are reviewed with regard to left atrial function
and surgical intervention. Finally, in chapter 11, the results of this thesis are summarized
and discussed. Since AF ablation is a rapidly evolving field, we would also like to offer
future perspectives.
Chap
ter 1
REfEREnCEs
(1) European Heart Rhythm Association, European Association for Cardio-Thoracic Surgery, Camm AJ, Kirchhof P, Lip GY, Schotten U, et al. Guidelines for the management of atrial fibrillation: the Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC). Europace 2010 Oct; 12(10): 1360-1420.
(2) Authors/Task Force Members, Camm AJ, Lip GY, De Caterina R, Savelieva I, Atar D, et al. 2012 fo-cused update of the ESC Guidelines for the management of atrial fibrillation: An update of the 2010 ESC Guidelines for the management of atrial fibrillation. Europace 2012 Aug 24.
(3) Wolf PA, Abbott RD, Kannel WB. Atrial fibrillation as an independent risk factor for stroke: the Framingham Study. Stroke 1991 Aug; 22(8): 983-988.
(4) Chugh SS, Havmoeller R, Narayanan K, Singh D, Rienstra M, Benjamin EJ, et al. Worldwide epidemi-ology of atrial fibrillation: a Global Burden of Disease 2010 Study. Circulation 2014 Feb 25; 129(8): 837-847.
(5) Kirchhof P, Benussi S, Kotecha D, Ahlsson A, Atar D, Casadei B, et al. 2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS. Eur Heart J 2016 Oct 7; 37(38): 2893-2962.
(6) Allessie MA, de Groot NM, Houben RP, Schotten U, Boersma E, Smeets JL, et al. Electropathological substrate of long-standing persistent atrial fibrillation in patients with structural heart disease: longitudinal dissociation. Circ Arrhythm Electrophysiol 2010 Dec; 3(6): 606-615.
(7) Spach MS, Josephson ME. Initiating reentry: the role of nonuniform anisotropy in small circuits. J Cardiovasc Electrophysiol 1994 Feb; 5(2): 182-209.
(8) Cosio FG, Aliot E, Botto GL, Heidbuchel H, Geller CJ, Kirchhof P, et al. Delayed rhythm control of atrial fibrillation may be a cause of failure to prevent recurrences: reasons for change to active antiarrhythmic treatment at the time of the first detected episode. Europace 2008 Jan; 10(1): 21-27. (9) Cosio FG, Aliot E, Botto GL, Heidbuchel H, Geller CJ, Kirchhof P, et al. Delayed rhythm control of
atrial fibrillation may be a cause of failure to prevent recurrences: reasons for change to active antiarrhythmic treatment at the time of the first detected episode. Europace 2008 Jan; 10(1): 21-27. (10) Nieuwlaat R, Capucci A, Camm AJ, Olsson SB, Andresen D, Davies DW, et al. Atrial fibrillation
management: a prospective survey in ESC member countries: the Euro Heart Survey on Atrial Fibril-lation. Eur Heart J 2005 Nov; 26(22): 2422-2434.
(11) Wyse DG, Waldo AL, DiMarco JP, Domanski MJ, Rosenberg Y, Schron EB, et al. A comparison of rate control and rhythm control in patients with atrial fibrillation. N Engl J Med 2002 Dec 5; 347(23): 1825-1833.
(12) Van Gelder IC, Hagens VE, Bosker HA, Kingma JH, Kamp O, Kingma T, et al. A comparison of rate control and rhythm control in patients with recurrent persistent atrial fibrillation. N Engl J Med 2002 Dec 5; 347(23): 1834-1840.
(13) Calkins H, Kuck KH, Cappato R, Brugada J, Camm AJ, Chen SA, et al. 2012 HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation. Europace 2012 Apr; 14(4): 528-606.
(14) EHRA Scientific Committee Task Force: , Gorenek B, Pelliccia A, Benjamin EJ, Boriani G, Crijns HJ, et al. European Heart Rhythm Association (EHRA)/European Association of Cardiovascular Prevention and Rehabilitation (EACPR) position paper on how to prevent atrial fibrillation endorsed by the Heart Rhythm Society (HRS) and Asia Pacific Heart Rhythm Society (APHRS). Europace 2016 Nov 4.
(15) Vermond RA, Geelhoed B, Verweij N, Tieleman RG, Van der Harst P, Hillege HL, et al. Incidence of Atrial Fibrillation and Relationship With Cardiovascular Events, Heart Failure, and Mortality: A Community-Based Study From the Netherlands. J Am Coll Cardiol 2015 Sep 1; 66(9): 1000-1007. (16) Nalliah CJ, Sanders P, Kottkamp H, Kalman JM. The role of obesity in atrial fibrillation. Eur Heart J
2015 Sep 14.
(17) Pathak RK, Middeldorp ME, Lau DH, Mehta AB, Mahajan R, Twomey D, et al. Aggressive risk factor reduction study for atrial fibrillation and implications for the outcome of ablation: the ARREST-AF cohort study. J Am Coll Cardiol 2014 Dec 2; 64(21): 2222-2231.
(18) Abed HS, Wittert GA, Leong DP, Shirazi MG, Bahrami B, Middeldorp ME, et al. Effect of weight reduc-tion and cardiometabolic risk factor management on symptom burden and severity in patients with atrial fibrillation: a randomized clinical trial. JAMA 2013 Nov 20; 310(19): 2050-2060.
(19) Pathak RK, Middeldorp ME, Meredith M, Mehta AB, Mahajan R, Wong CX, et al. Long-Term Effect of Goal-Directed Weight Management in an Atrial Fibrillation Cohort: A Long-Term Follow-Up Study (LEGACY). J Am Coll Cardiol 2015 May 26; 65(20): 2159-2169.
(20) Lau DH, Schotten U, Mahajan R, Antic NA, Hatem SN, Pathak RK, et al. Novel mechanisms in the pathogenesis of atrial fibrillation: practical applications. Eur Heart J 2016 May 21; 37(20): 1573-1581. (21) Wynn GJ, Todd DM, Webber M, Bonnett L, McShane J, Kirchhof P, et al. The European Heart Rhythm
Association symptom classification for atrial fibrillation: validation and improvement through a simple modification. Europace 2014 Jul; 16(7): 965-972.
(22) Cox JL, Schuessler RB, D’Agostino HJ,Jr, Stone CM, Chang BC, Cain ME, et al. The surgical treatment of atrial fibrillation. III. Development of a definitive surgical procedure. J Thorac Cardiovasc Surg 1991 Apr; 101(4): 569-583.
(23) Prasad SM, Maniar HS, Camillo CJ, Schuessler RB, Boineau JP, Sundt TM,3rd, et al. The Cox maze III procedure for atrial fibrillation: long-term efficacy in patients undergoing lone versus concomitant procedures. J Thorac Cardiovasc Surg 2003 Dec; 126(6): 1822-1828.
(24) Hemels ME, Gu YL, Tuinenburg AE, Boonstra PW, Wiesfeld AC, van den Berg MP, et al. Favorable long-term outcome of Maze surgery in patients with lone atrial fibrillation. Ann Thorac Surg 2006 May; 81(5): 1773-1779.
(25) Cox JL, Ad N, Palazzo T. Impact of the maze procedure on the stroke rate in patients with atrial fibrillation. J Thorac Cardiovasc Surg 1999 Nov; 118(5): 833-840.
(26) Lawrance CP, Henn MC, Miller JR, Sinn LA, Schuessler RB, Maniar HS, et al. A minimally invasive Cox maze IV procedure is as effective as sternotomy while decreasing major morbidity and hospital stay. J Thorac Cardiovasc Surg 2014 Sep; 148(3): 955-61; discussion 962-2.
(27) Henn MC, Lancaster TS, Miller JR, Sinn LA, Schuessler RB, Moon MR, et al. Late outcomes after the Cox maze IV procedure for atrial fibrillation. J Thorac Cardiovasc Surg 2015 Nov; 150(5): 1168-76, 1178.e1-2.
(28) Gillinov AM, Gelijns AC, Parides MK, DeRose JJ,Jr, Moskowitz AJ, Voisine P, et al. Surgical ablation of atrial fibrillation during mitral-valve surgery. N Engl J Med 2015 Apr 9; 372(15): 1399-1409. (29) Ad N, Suri RM, Gammie JS, Sheng S, O’Brien SM, Henry L. Surgical ablation of atrial fibrillation
trends and outcomes in North America. J Thorac Cardiovasc Surg 2012 Nov; 144(5): 1051-1060. (30) Haissaguerre M, Jais P, Shah DC, Takahashi A, Hocini M, Quiniou G, et al. Spontaneous initiation
of atrial fibrillation by ectopic beats originating in the pulmonary veins. N Engl J Med 1998 Sep 3; 339(10): 659-666.
(31) Dewire J, Calkins H. State-of-the-art and emerging technologies for atrial fibrillation ablation. Nat Rev Cardiol 2010 Mar; 7(3): 129-138.
Chap
ter 1
(32) Nielsen JC, Johannessen A, Raatikainen P, Hindricks G, Walfridsson H, Pehrson SM, et al. Long-term efficacy of catheter ablation as first-line therapy for paroxysmal atrial fibrillation: 5-year outcome in a randomised clinical trial. Heart 2016 Aug 26.
(33) Morillo CA, Verma A, Connolly SJ, Kuck KH, Nair GM, Champagne J, et al. Radiofrequency ablation vs antiarrhythmic drugs as first-line treatment of paroxysmal atrial fibrillation (RAAFT-2): a random-ized trial. JAMA 2014 Feb 19; 311(7): 692-700.
(34) Calkins H, Reynolds MR, Spector P, Sondhi M, Xu Y, Martin A, et al. Treatment of atrial fibrillation with antiarrhythmic drugs or radiofrequency ablation: two systematic literature reviews and meta-analyses. Circ Arrhythm Electrophysiol 2009 Aug; 2(4): 349-361.
(35) Weerasooriya R, Khairy P, Litalien J, Macle L, Hocini M, Sacher F, et al. Catheter ablation for atrial fibrillation: are results maintained at 5 years of follow-up? J Am Coll Cardiol 2011 Jan 11; 57(2): 160-166.
(36) Nanthakumar K, Plumb VJ, Epstein AE, Veenhuyzen GD, Link D, Kay GN. Resumption of electrical conduction in previously isolated pulmonary veins: rationale for a different strategy? Circulation 2004 Mar 16; 109(10): 1226-1229.
(37) Ouyang F, Tilz R, Chun J, Schmidt B, Wissner E, Zerm T, et al. Long-term results of catheter ablation in paroxysmal atrial fibrillation: lessons from a 5-year follow-up. Circulation 2010 Dec 7; 122(23): 2368-2377.
(38) Tilz RR, Rillig A, Thum AM, Arya A, Wohlmuth P, Metzner A, et al. Catheter ablation of long-standing persistent atrial fibrillation: 5-year outcomes of the Hamburg Sequential Ablation Strategy. J Am Coll Cardiol 2012 Nov 6; 60(19): 1921-1929.
(39) Verma A, Jiang CY, Betts TR, Chen J, Deisenhofer I, Mantovan R, et al. Approaches to catheter abla-tion for persistent atrial fibrillaabla-tion. N Engl J Med 2015 May 7; 372(19): 1812-1822.
(40) Neumann T, Vogt J, Schumacher B, Dorszewski A, Kuniss M, Neuser H, et al. Circumferential pulmo-nary vein isolation with the cryoballoon technique results from a prospective 3-center study. J Am Coll Cardiol 2008 Jul 22; 52(4): 273-278.
(41) Chun KR, Schmidt B, Metzner A, Tilz R, Zerm T, Koster I, et al. The ‚single big cryoballoon‘ technique for acute pulmonary vein isolation in patients with paroxysmal atrial fibrillation: a prospective observational single centre study. Eur Heart J 2009 Mar; 30(6): 699-709.
(42) Packer DL, Kowal RC, Wheelan KR, Irwin JM, Champagne J, Guerra PG, et al. Cryoballoon ablation of pulmonary veins for paroxysmal atrial fibrillation: first results of the North American Arctic Front (STOP AF) pivotal trial. J Am Coll Cardiol 2013 Apr 23; 61(16): 1713-1723.
(43) Andrade JG, Khairy P, Guerra PG, Deyell MW, Rivard L, Macle L, et al. Efficacy and safety of cryobal-loon ablation for atrial fibrillation: a systematic review of published studies. Heart Rhythm 2011 Sep; 8(9): 1444-1451.
(44) Kuck KH, Brugada J, Furnkranz A, Metzner A, Ouyang F, Chun KR, et al. Cryoballoon or Radiofre-quency Ablation for Paroxysmal Atrial Fibrillation. N Engl J Med 2016 Jun 9; 374(23): 2235-2245. (45) Neumann T, Wojcik M, Berkowitsch A, Erkapic D, Zaltsberg S, Greiss H, et al. Cryoballoon ablation
of paroxysmal atrial fibrillation: 5-year outcome after single procedure and predictors of success. Europace 2013 Aug; 15(8): 1143-1149.
(46) Klinkenberg TJ, Ahmed S, Ten Hagen A, Wiesfeld AC, Tan ES, Zijlstra F, et al. Feasibility and outcome of epicardial pulmonary vein isolation for lone atrial fibrillation using minimal invasive surgery and high intensity focused ultrasound. Europace 2009 Dec; 11(12): 1624-1631.
(47) Pozzoli A, Benussi S, Anzil F, Taramasso M, Privitera YA, Cianflone D, et al. Electrophysiological ef-ficacy of Epicor high-intensity focused ultrasound. Eur J Cardiothorac Surg 2012 Jul; 42(1): 129-34; discussion 134.
(48) Wolf RK, Schneeberger EW, Osterday R, Miller D, Merrill W, Flege JB,Jr, et al. Video-assisted bilateral pulmonary vein isolation and left atrial appendage exclusion for atrial fibrillation. J Thorac Cardio-vasc Surg 2005 Sep; 130(3): 797-802.
(49) Yilmaz A, Van Putte BP, Van Boven WJ. Completely thoracoscopic bilateral pulmonary vein isolation and left atrial appendage exclusion for atrial fibrillation. J Thorac Cardiovasc Surg 2008 Aug; 136(2): 521-522.
(50) Boersma LV, Castella M, van Boven W, Berruezo A, Yilmaz A, Nadal M, et al. Atrial fibrillation catheter ablation versus surgical ablation treatment (FAST): a 2-center randomized clinical trial. Circulation 2012 Jan 3; 125(1): 23-30.
(51) Santini M, Loiaconi V, Tocco MP, Mele F, Pandozi C. Feasibility and efficacy of minimally invasive stand-alone surgical ablation of atrial fibrillation. A single-center experience. J Interv Card Electro-physiol 2012 Jan 11.
(52) Han FT, Kasirajan V, Kowalski M, Kiser R, Wolfe L, Kalahasty G, et al. Results of a minimally invasive surgical pulmonary vein isolation and ganglionic plexi ablation for atrial fibrillation: single-center experience with 12-month follow-up. Circ Arrhythm Electrophysiol 2009 Aug; 2(4): 370-377. (53) Edgerton JR, Brinkman WT, Weaver T, Prince SL, Culica D, Herbert MA, et al. Pulmonary vein
isola-tion and autonomic denervaisola-tion for the management of paroxysmal atrial fibrillaisola-tion by a minimally invasive surgical approach. J Thorac Cardiovasc Surg 2010 Oct; 140(4): 823-828.
(54) Yilmaz A, Geuzebroek GS, Van Putte BP, Boersma LV, Sonker U, De Bakker JM, et al. Completely thoracoscopic pulmonary vein isolation with ganglionic plexus ablation and left atrial appendage amputation for treatment of atrial fibrillation. Eur J Cardiothorac Surg 2010 Sep; 38(3): 356-360. (55) Kasirajan V, Spradlin EA, Mormando TE, Medina AE, Ovadia P, Schwartzman DS, et al. Minimally
invasive surgery using bipolar radiofrequency energy is effective treatment for refractory atrial fibrillation. Ann Thorac Surg 2012 May; 93(5): 1456-1461.
(56) De Maat GE, Pozzoli A, Scholten MF, Hillege HL, Van Gelder IC, Alfieri OR, et al. Surgical minimally invasive pulmonary vein isolation for lone atrial fibrillation: midterm results of a multicenter study. Innovations (Phila) 2013 Nov-Dec; 8(6): 410-415.
(57) Weimar T, Vosseler M, Czesla M, Boscheinen M, Hemmer WB, Doll KN. Approaching a paradigm shift: endoscopic ablation of lone atrial fibrillation on the beating heart. Ann Thorac Surg 2012 Dec; 94(6): 1886-1892.
(58) De Maat GE, Van Gelder IC, Rienstra M, Quast AF, Tan ES, Wiesfeld AC, et al. Surgical vs. trans-catheter pulmonary vein isolation as first invasive treatment in patients with atrial fibrillation: a matched group comparison. Europace 2014 Jan; 16(1): 33-39.
(59) De Maat GE, Pozzoli A, Scholten MF, Van Gelder IC, Blaauw Y, Mulder BA, et al. Long-term results of surgical minimally invasive pulmonary vein isolation for paroxysmal lone atrial fibrillation. Europace 2015 May; 17(5): 747-752.
(60) Pison L, La Meir M, van Opstal J, Blaauw Y, Maessen J, Crijns HJ. Hybrid thoracoscopic surgical and transvenous catheter ablation of atrial fibrillation. J Am Coll Cardiol 2012 Jul 3; 60(1): 54-61. (61) Krul SP, Driessen AH, van Boven WJ, Linnenbank AC, Geuzebroek GS, Jackman WM, et al.
Thora-coscopic video-assisted pulmonary vein antrum isolation, ganglionated plexus ablation, and peri-procedural confirmation of ablation lesions: first results of a hybrid surgical-electrophysiological approach for atrial fibrillation. Circ Arrhythm Electrophysiol 2011 Jun 1; 4(3): 262-270.
(62) Pison L, Gelsomino S, Luca F, Parise O, Maessen JG, Crijns HJ, et al. Effectiveness and safety of simultaneous hybrid thoracoscopic and endocardial catheter ablation of lone atrial fibrillation. Ann Cardiothorac Surg 2014 Jan; 3(1): 38-44.
Chap
ter 1
(63) Bulava A, Mokracek A, Hanis J, Kurfirst V, Eisenberger M, Pesl L. Sequential hybrid procedure for persistent atrial fibrillation. J Am Heart Assoc 2015 Mar 25; 4(3): e001754.
(64) Kotecha D, Lam CS, Van Veldhuisen DJ, Van Gelder IC, Voors AA, Rienstra M. Heart Failure With Preserved Ejection Fraction and Atrial Fibrillation: Vicious Twins. J Am Coll Cardiol 2016 Nov 15; 68(20): 2217-2228.
(65) Wang TJ, Larson MG, Levy D, Vasan RS, Leip EP, Wolf PA, et al. Temporal relations of atrial fibrillation and congestive heart failure and their joint influence on mortality: the Framingham Heart Study. Circulation 2003 Jun 17; 107(23): 2920-2925.
(66) Olsson LG, Swedberg K, Ducharme A, Granger CB, Michelson EL, McMurray JJ, et al. Atrial fibril-lation and risk of clinical events in chronic heart failure with and without left ventricular systolic dysfunction: results from the Candesartan in Heart failure-Assessment of Reduction in Mortality and morbidity (CHARM) program. J Am Coll Cardiol 2006 May 16; 47(10): 1997-2004.
(67) Pozzoli A, Taramasso M, Coppola G, Kamami M, La Canna G, Bella PD, et al. Maze surgery normalizes left ventricular function in patients with persistent lone atrial fibrillation. Eur J Cardiothorac Surg 2014 Mar 5.
(68) Di Biase L, Mohanty P, Mohanty S, Santangeli P, Trivedi C, Lakkireddy D, et al. Ablation Versus Amio-darone for Treatment of Persistent Atrial Fibrillation in Patients With Congestive Heart Failure and an Implanted Device: Results From the AATAC Multicenter Randomized Trial. Circulation 2016 Apr 26; 133(17): 1637-1644.
(69) Anselmino M, Matta M, D’Ascenzo F, Bunch TJ, Schilling RJ, Hunter RJ, et al. Catheter ablation of atrial fibrillation in patients with left ventricular systolic dysfunction: a systematic review and meta-analysis. Circ Arrhythm Electrophysiol 2014 Dec; 7(6): 1011-1018.
(70) Khan MN, Jais P, Cummings J, Di Biase L, Sanders P, Martin DO, et al. Pulmonary-vein isolation for atrial fibrillation in patients with heart failure. N Engl J Med 2008 Oct 23; 359(17): 1778-1785. (71) Hsu LF, Jais P, Sanders P, Garrigue S, Hocini M, Sacher F, et al. Catheter ablation for atrial fibrillation
in congestive heart failure. N Engl J Med 2004 Dec 2; 351(23): 2373-2383.
(72) van Walraven C, Hart RG, Singer DE, Laupacis A, Connolly S, Petersen P, et al. Oral anticoagulants vs aspirin in nonvalvular atrial fibrillation: an individual patient meta-analysis. JAMA 2002 Nov 20; 288(19): 2441-2448.
(73) Friberg L, Rosenqvist M, Lip GY. Net clinical benefit of warfarin in patients with atrial fibrillation: a report from the Swedish atrial fibrillation cohort study. Circulation 2012 May 15; 125(19): 2298-2307.
(74) Bunch TJ, May HT, Bair TL, Weiss JP, Crandall BG, Osborn JS, et al. Atrial fibrillation ablation patients have long-term stroke rates similar to patients without atrial fibrillation regardless of CHADS2 score. Heart Rhythm 2013 Sep; 10(9): 1272-1277.
(75) Onalan O, Crystal E. Left atrial appendage exclusion for stroke prevention in patients with nonrheu-matic atrial fibrillation. Stroke 2007 Feb; 38(2 Suppl): 624-630.
(76) Odell JA, Blackshear JL, Davies E, Byrne WJ, Kollmorgen CF, Edwards WD, et al. Thoracoscopic obliteration of the left atrial appendage: potential for stroke reduction? Ann Thorac Surg 1996 Feb; 61(2): 565-569.
(77) Dunning J, Nagendran M, Alfieri OR, Elia S, Kappetein AP, Lockowandt U, Sarris GE, Kohl PH. Guide-line for the surgical treatment of atrial fibrillation. 2013; doi: 10.1093/ejcts/ezt413.
(78) Healey JS, Crystal E, Lamy A, Teoh K, Semelhago L, Hohnloser SH, et al. Left Atrial Appendage Occlu-sion Study (LAAOS): results of a randomized controlled pilot study of left atrial appendage occluOcclu-sion during coronary bypass surgery in patients at risk for stroke. Am Heart J 2005 Aug; 150(2): 288-293.
(79) Kanderian AS, Gillinov AM, Pettersson GB, Blackstone E, Klein AL. Success of surgical left atrial ap-pendage closure: assessment by transesophageal echocardiography. J Am Coll Cardiol 2008 Sep 9; 52(11): 924-929.
(80) Piccini JP, Sievert H, Patel MR. Left atrial appendage occlusion: rationale, evidence, devices, and patient selection. Eur Heart J 2016 Sep 13.
