Combined catheter ablation and left atrial appendage closure as a hybrid procedure for the treatment of atrial fibrillation
Combined catheter ablation and left atrial appendage closure as a hybrid procedure for the treatment of atrial fibrillation
Naiara Calvo 0
Nahikari Salterain 0
Hugo Arguedas 0
Alfonso Macias 0
Alberto Esteban 0
Manuel Garc´ıa de Ye´ benes 0
Juan J. Gavira 0
Joaqu´ın Barba 0
Ignacio Garc´ıa-Bolao 0
0 Arrhythmia Unit, Department of Cardiology and Cardiac Surgery, University of Navarra , Av Pio XII, 36, 31008 Pamplona , Spain
Aims Left atrial appendage (LAA) is the source of thrombi in up to 90% of patients with non-valvular atrial fibrillation (AF). Catheter ablation (CA) is an effective treatment for symptomatic AF and, in selected cases, LAA occlusion devices have been introduced as an alternative to oral anticoagulants (OACs). The safety and feasibility of combining CA and percutaneous LAA closure (LAAC) are unknown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Methods Patients with symptomatic drug-refractory AF, CHADS2 score of ≥1, and CHA2DS2-VASc score ≥2 were included. and results Catheter ablation consisted in pulmonary vein isolation with or without roof line with radiofrequency and LAA was occluded with the Watchman or Amplatzer Cardiac Plug (ACP) devices guided by angiography and transoesophageal echocardiography. A total of 35 patients were included (71% male; 70 years). Median score was 3 on both CHA2DS2VASc and HAS-BLED, 9% had prior stroke under OAC, and 48% had bleeding complications. Successful CA and device implantation were achieved in 97% of cases. The Watchman device was used in 29 patients and ACP in 6 patients. Periprocedural complications included three cases of cardiac tamponade. At 3 months, all patients met the criteria for successful sealing of the LAA. After a mean follow-up of 13 months (3 - 75), 78% of patients were free of arrhythmia recurrences and OAC was withheld in 97% of patients. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conclusions The combination of CA and percutaneous LAAC in a single procedure is technically feasible in patients with symptomatic drug-refractory AF, high risk of stroke, and contraindications to OACs, although it is associated with a significant risk of major complications. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
The overall risk of stroke in patients with non-valvular atrial
fibrillation (AF) is as high as 5% per year.1 The left atrial appendage
(LAA) has been shown to be the source of thrombi in up to 90% of
the patients with non-valvular AF.2 – 4 According to the ESC
guidelines, oral anticoagulant (OAC) therapy is indicated in all patients at
high thrombo-embolic risk.5 Although both warfarin/acenocumarol
or the more recently introduced factor II/Xa inhibitors can
significantly reduce the risk of stroke in at-risk patients with AF,
these OAC medications are associated with severe haemorrhagic
complications.6 – 9
These challenges have led to interest in mechanical exclusion of
the LAA to prevent thromboembolism in AF. Devices for
percutaneous ligation have shown efficacy and safety in achieving this goal
when OAC is contraindicated or declined by the patient.10,11 The
ESC guidelines on AF recommend that LAA closure (LAAC) may
be considered in patients with high stroke risk and contraindications
for long-term OAC use (Class IIb).5
Atrial fibrillation catheter ablation (AFCA) is an effective rhythm
control strategy for patients with symptomatic, drug-refractory
AF12 but its role in stroke prevention remains unproved. According
to guidelines, post-procedural anticoagulation is considered
mandatory for at least 2 months after AFCA, regardless of the baseline
† Percutaneous LAA occlusion has shown efficacy and relative
safety in achieving the goal of preventing thromboembolism
in AF patients who do not wish or cannot receive OAC. In a
controlled randomized study, the Watchman device
demonstrated non-inferiority and later superiority when compared
with warfarin in reducing stroke.
† According to clinical guidelines, percutaneous occlusion of the
LAA is indicated in patients with thrombo-embolic risk who
cannot be managed with OAC in the long term (indication IIb).
† Combining CA and percutaneous LAA closure procedures in
a single session are technically feasible, although it is associated
with a significant risk (9%) of major complications.
thrombo-embolic risk, and discontinuation of systemic
anticoagulation therapy post-ablation is not recommended in patients
with high risk of stroke.
Combining AFCA and percutaneous LAAC could reduce the
incidence of stroke in selected high-risk patients while simultaneously
relieving AF symptoms in a single session. The aim of this study was to
report the feasibility and outcomes of a combined procedure of
AFCA and percutaneous LAAC.
Patients with symptomatic drug-refractory AF, a CHADS2 score of ≥1, a
CHA2DS2-VASc score ≥2 and relative or absolute contraindications for
OACs, or who refused OAC therapy despite adequate information were
prospectively included. Thrombo-embolic and bleeding risk were
defined according to the CHADS2/CHA2DS2-VASc and HAS-BLED
Written informed consent was obtained from all participants. The
protocol was approved by the Ethics Committee of our institution.
The day before the procedure, patients underwent a transoesophageal
echocardiography (TOE) and a cardiac CT scan. Pre-procedural TOE
was utilized to document the absence of thrombi within the LAA,
assess the features and type of the LAA, and determine the appropriate
device size or type.
Patients were instructed to withhold acenocumarol therapy 3 days
prior to the procedure and to start low molecular weight heparin
(LMWH) 2 days before the ablation until the night before. Novel
OACs (NOACs) were interrupted the day before the procedure.
Atrial fibrillation catheter ablation procedure
The procedure was performed under general anaesthesia because of
TOE guidance during transseptal puncture and LAAC.
A decapolar diagnostic catheter was positioned in the coronary sinus
through the left femoral venous access. Through the right femoral vein,
two transseptal accesses were obtained. Both pressure monitoring
through the Brockenbrough needle and TOE were used to guide the
double transseptal puncture. Inferior and posterior transseptal
punctures were performed to allow further coaxial alignment with the
appendage during LAAC.
Boluses of unfractionated heparin were given after the transseptal
punctures according to a previously defined protocol,13 to achieve
activated clotting time .250 – 300 s.
A circular mapping catheter (Spiral, St Jude Medical) was used to map
pulmonary vein (PV) potentials. Three-dimensional reconstruction of the
left atrium and PVs was performed from the CT scan using Ensite NavX
Verismo software (St Jude Medical, St Paul, MN, USA).
A steerable sheath (Agilis NXT, St Jude Medical) and a 4.0 open
irrigated-tip catheter (Cool Path, St Jude Medical) were used to ablate
the antrum of the PVs. In cases of paroxysmal AF, only PV isolation was
performed. A roof line with demonstration of bidirectional block was
performed in persistent cases. The CA endpoint was to eliminate local
PV potentials and bidirectional conduction block between the left
atrium and PVs.
Left atrial appendage closure
Immediately after the AFCA, the LAAC procedure was performed by the
same operator using fluoroscopy and TOE guidance. Prophylactic
antibiotic with ceftriaxone was given at the end of the AFCA. Either
Watchman (Boston Scientific) or Amplatzer Cardiac Plug (ACP) (St Jude
Medical) devices were implanted, according to the LAA size and
morphology and physician preferences. The more inferior and posterior
transseptal sheath location was retained while the second sheath was
withdrawn to the venous circulation. Once normal LA filling pressures
(a mean LAA pressure measurement of ≥10 mmHg) were obtained,
LAA ostial and depth dimensions were reassessed during AFCA by
TOE. Implant of a Watchman or ACP LAA occluder device was then
performed as previously described.14 Briefly, the initial transseptal sheath
was replaced by a 9 – 14 F access sheath and a pigtail catheter was
positioned in the LAA. Angiography of the LAA was performed in right
anterior oblique (RAO) caudal and cranial views, delineating shape and size.
A device size 10 – 20% greater than the largest diameter of the LAA
body (as measured by TOE) was chosen. The sheath was then advanced
over the pigtail catheter until the proximal marker corresponding with
the device size matched the LAA ostium (in the case of Watchman
device) or at least 15 mm inside the LAA (in the case of ACP). The
pigtail was removed and the delivery catheter and device were advanced
into the LAA. The devices were delivered by sheath retraction (combined
with gentle pushing on the ACP device).
A sustained tug test for stability and several criteria [proper LAA
position, no or minimal (,5 mm) residual lateral flow past the device] was
fulfilled before releasing the devices. After the release, the device position
was reconfirmed by angiography and TOE.
A TOE was performed if the device was not properly identified by a
chest X-ray and a transthoracic echocardiography, and patients were
discharged the next day. Endocarditis prophylaxis was recommended for
the first 6 months.
Anticoagulation was restarted with LMWH at a dose of 1 mg/kg/12 h
while also restarting acenocumarol until the therapeutic international
normalized ratio (INR) goal of 2.0 – 3.0 s was reached. Aspirin 100 mg
was started the day after the procedure.
The post-procedure anticoagulation regimen was adopted based on
HRS/EHRA/ECAS Expert Consensus Statement on Catheter and
Surgical Ablation of Atrial Fibrillation, PROTECT AF trial and LAA occluders’
instructions. According to HRS/EHRA/ECAS Expert Consensus
Statement, systemic anticoagulation with warfarin or with a direct thrombin
or Factor Xa inhibitor is recommended for all patients for at least
2 months following AFCA. The anticoagulation protocol of the
PROTECT AF trial [OAC for 6 weeks, dual antiplatelet therapy (DAT)
for 6 months, and aspirin for life] was adopted in the instructions for the
use of the Watchman device. In the instructions for the use of the
Amplatzer device, DAT only without an OAC is indicated.
Following these recommendations of the anticoagulation regimen
after AFCA and after LAAC procedure, patients were on OAC and
aspirin for a minimum of 3 months after the procedure.
Follow-up consisted of outpatient clinic visits at 3, 6, and 12 months, and
included a detailed history, 12-lead ECG, and 48 h Holter monitoring.
Patients were instructed to contact the research team if any new
symptoms or events requiring medical attention happened after the
At the first visit, a TOE was performed to evaluate LAA occlusion,
thrombus formation, device position, and residual peri-device flow. If
the echocardiographic criteria for successful sealing of the LAA were
met (complete LAA occlusion or residual shunt ,5 mm jet width
in the absence of device surface thrombi), acenocumarol could be
In patients who underwent Watchman implantation, aspirin was
continued indefinitely, and clopidogrel was started (75 mg daily) for
In patients receiving ACP, aspirin was continued for 3 – 4 months, or
lifelong unless contraindicated.
If these echocardiographic criteria for successful sealing were not met,
anticoagulation was maintained and TOE was repeated at 6 months.
Antiarrhythmic drug therapy was ceased after 3 months if no clinical or
documented AF recurrences were identified.
Acute and long-term outcome
Acute and long-term clinical outcomes included a successful implantation
without major adverse events. Major complication was considered if any
death, longer hospital stay, major disability, or rehospitalization occurred.
Major bleeding was defined as any vascular complications requiring
percutaneous/surgical intervention or blood transfusion and pericardial
effusions requiring percutaneous/surgical drainage or repair.
Thromboembolic complications included ischaemic stroke or embolism, transient
ischaemic attacks (TIA), and deep vein thrombosis.
Freedom from left atrial arrhythmias was described after a blanking
period of 3 months.
Continuous variables are presented as mean + standard deviation.
Categorical variables are reported as percentages. All statistical analyses
were performed using SPSS version 19 for Windows (SPSS Statistics,
IBM Software Group).
A total of 35 patients [25 (71%) men, 70 + 7 years] were included.
Baseline characteristics are shown in Table 1. The mean CHADS2
score was 2.01 and CHA2DS2-VASc score was 3.1 (range 2 – 6).
A history of prior stroke under OACs was present in 3 (9%) patients,
and 17 (48%) had a history of a bleeding event. Median HAS-BLED
score was 3 (range 2 – 6). Before the procedure, 24 patients (69%)
were receiving acenocumarol for stroke prophylaxis. Atrial
fibrillation was paroxysmal in 10 patients (29%) and persistent in the
remaining 25 patients. Technical data on implants are shown in
Table 2. Acute ablation endpoints and device implantation were
achieved successfully in all patients but one (97% success). In the
remaining patient, after AFCA was performed, LAA ostial and depth
dimensions were reassessed by TOE and angiography. Left atrial
appendage closure was then aborted because LAA maximum ostial
diameter and depth did not permit placing the initially planned Watchman
device. Left atrial appendage closure procedure was performed the
following day and an ACP device was successfully implanted.
A Watchman device was implanted (Figure 1) in 29 (82%) patients
and an ACP (Figure 2) in 6 (18%) patients. In one patient, owing to the
unsatisfactory compression diameter after expansion, the device was
retrieved and a larger one was successfully deployed, which resulted
in a median of 1.3 devices per patient.
The mean total combined procedure time was 160.5 + 33.75 min,
while the mean subsequent LAAC procedure time was 42.05 +
The periprocedural complications included three cases (8.57%) of
severe pericardial effusion successfully treated by pericardiocentesis.
In one of the cases, a light pericardial effusion was noticed at the end
of the AFCA procedure, without haemodynamic compromise. Once
the LAAC was successfully completed, the pericardial effusion had
become significant, so a pericardiocentesis was performed. In the
remaining two cases, the tamponade occurred at the end of the
No thrombo-embolic complications were found. Mean hospital
stay was 2.9 + 3.7 days.
At 3-month follow-up, 35 patients (100%) met the criteria for
successful sealing of the LAA. Oral anticoagulant was interrupted in 27
patients (77%): clopidogrel was initiated in all of these patients with
a Watchman device, and all patients with an ACP device except
one continued aspirin indefinitely (Figure 3).
Oral anticoagulant was maintained in eight patients (23%), mainly
(5/8) due to AF recurrences within the blanking period (Figure 3).
Four patients underwent an electrical cardioversion and OAC
were interrupted at 6-month follow-up. In a patient with paroxysmal
symptomatic recurrences, a redo ablation was performed. The LAA
device (Watchman device) was not affected and did not interfere
with the redo procedure. Oral anticoagulant was maintained until
the redo ablation was performed (4 months after the initial AFCA)
and during the first 3 months thereafter. In another patient, a
typical flutter appeared during follow-up. Cavotricuspid isthmus
ablation was performed and OAC was maintained 1 month after this
procedure. In one patient, the OAC was maintained according to
the cardiologist’s preference on the basis of recurrent stroke
episodes under therapeutic OAC levels prior to the combined AFCA/
The remaining patient had a peri-device (Watchman) leak of 4 mm
width. In this patient, OAC was maintained and a TOE was performed
at 3 months, which showed complete sealing of LAA; OAC was then
There were no device embolization events during follow-up. Two
patients developed haematuria within the first 3 months
postprocedure while still on OACs and antiplatelet therapy; both
There was one case of TIA at 2 years post-procedure. The TOE did
not reveal LA thrombus and there was complete closure of the LAA.
This patient was placed on clopidogrel for secondary prevention.
One patient had a sudden death 17 days after the procedure. He
was on OAC and aspirin. Although the INR monitoring 2 days
before his death showed an extremely high value,9 no immediate
measures were taken to correct these supratherapeutic levels. The
autopsy revealed an intracerebral haematoma.
At a mean follow-up of 13 months (
3 – 75
), 78% of patients were
free of arrhythmia recurrences and 97% discontinued OAC
(Figure 3). The observed ischaemic stroke rate was 2.6% per year.
Our study reveals that the combination of AFCA and percutaneous
LAA occlusion in a single procedure is a feasible strategy in patients
with symptomatic drug-refractory AF, contraindications or
resistance to taking OAC, and high risk of stroke.
The Watchman device is the only LAA occlusion device that has
been evaluated in randomized trials.15,16 The PROTECT AF study15
was designed to assess the non-inferiority of the device against
warfarin therapy. Adverse events in the Watchman group occurred
primarily on the day of the procedure, while the event rate was lower
than that of the control group after the periprocedural period.
The effect of increased operator experience was demonstrated in
the CAP16 registry with shorter implant time, higher implant success
rate, lower complications, and higher warfarin discontinuation rate.
The PREVAIL study15 confirmed that procedural complications
occurring after Watchman LAA occlusion were infrequent and
significantly improved compared with the PROTECT AF trial.
Watchman LAA occlusion was non-inferior to warfarin for the prevention
of stroke and systemic embolism beginning 1 week after
randomization. However, non-inferiority was not achieved for overall efficacy
(ischaemic stroke, systemic embolism, and cardiovascular or
unexplained death) at 18 months of follow-up, probably because the
event rates were unexpectedly low in the warfarin group.
More recently, the ASAP registry17 included 150 patients with
nonvalvular AF and a CHADS2 score .1 who were ineligible for OAC
therapy. Following the Watchman implant, patients were administered
6 months of clopidogrel or ticlopidine and lifelong aspirin. The
ischaemic stroke rate was less than that expected based on the CHADS2
scores of the cohort, suggesting that LAAC with the Watchman
device can be safely performed without a warfarin transition.
Data on the safety and feasibility of LAAC with the ACP device
comes from retrospective registries,14 with a technical success of
97 – 100%, a major complications rate between 2 and 7% and an
ischaemic stroke rate lower than would be expected from the
CHADS2 scores of the patient cohort.
To date, only a few studies have evaluated the safety and feasibility
of a combined strategy of AFCA and percutaneous LAAC with the
Watchman device. A combined approach could reduce the risk
associated with a new vascular access, a new transseptal puncture for
LAAC, and anticoagulation during the procedure. Furthermore, in
patients with a significant risk of thrombo-embolic events and a
strict or relative contraindication to (N)OACs undergoing an
ablation procedure to treat symptomatic AF, the combined procedure
might reduce the risk of thrombo-embolic or haemorrhagic
complications after AFCA procedure.
The disadvantages of the combined procedure are the regular use
of general anaesthesia because of continuous TOE monitoring, and
longer procedure and fluoroscopy times. Additionally, patients are
required to be on OAC for at least the first 2 – 3 months after the
procedure. However, the use of antiplatelet therapy, NOACs, or LMWH
for a shorter period of time might be an alternative, although further
studies are needed to determine the role of these drugs in ablation
Swaans et al.18 evaluated 30 patients who had AFCA using
multielectrode catheters and LAAC (Watchman). Successful Watchman
device implantation was achieved with a median of 1.5 devices. At 60
days, all patients had successful LAA sealing. At 12-month follow-up,
no thrombo-embolic events occurred with a 30% of AF recurrence.
Walker et al.19 included patients who underwent PV isolation
procedures by radiofrequency ablation, followed by implant of a
Watchman device. There were no acute complications. At 6-week
follow-up, all patients had satisfactory LAA occlusion. Twenty
patients remained free of arrhythmia at follow-up.
Although all of these studies are limited single-centre experiences
and therefore the findings do not allow a general recommendation,
the EHRA/EAPCI consensus on catheter-based LAA occlusion14
suggests that patients with a significant risk of thrombo-embolic events
(CHA2DS2-VASc score .2) undergoing an AFCA procedure, who
also have a strict or relative contraindication to OACs, might be
Our study describes for the first time the feasibility and outcomes
of a combined AFCA/LAAC procedure with either Watchman or
ACP devices. In our experience, a successful implantation was
achieved on the first attempt in 97% of patients. The rate of major
complications, mostly pericardial tamponade, was higher than in
the two previous studies discussed but in line with that reported
in randomized and non-randomized registries. The cardiac
tamponade may happen due to an incorrect transseptal puncture or
manipulation of catheters, guidewires, or devices in the LA or the LAA,
leading to injuries of the left atrial or LAA wall. In addition, the
anticoagulation regimen required during AFCA and LAAC procedures
could increase the risk of bleeding complications. Furthermore, we
describe the experience of a combined AFCA/LAAC procedure
with two different devices, which could represent a longer learning
curve. At 90 days, all patients met the criteria for successful sealing.
Although 22% of patients had a documented AF recurrence, none
of them were still using OAC at a mean follow-up of 13 months.
The mean CHADS2 score was 2.01, which equates to a predicted
ischaemic stroke rate of 4.5% per year (3.5 – 5.9) using data from a
cohort of AF patients taking aspirin.20 Thus, our observed ischaemic
stroke rate of 2.6% per year represents 42.3% fewer events than
According to current guidelines, decisions regarding the use of
systemic anticoagulation .2 months post-ablation should be
based on the patient’s risk factors for stroke and discontinuation
of anticoagulation post-ablation is not recommended in patients
who are at high risk of stroke. These recommendations are
based on the following observations: (i) AF recurrences are
common post-ablation, (ii) asymptomatic AF is common
postablation, (iii) AF ablation destroys a portion of the atria, with an
unknown impact on long-term stroke risk, and (iv) no randomized
trials have assessed the safety of stopping anticoagulation in this
population. These arguments highlight the advantage of our
strategy of combining ablation and LAAC in selected patients—those
with AF and high stroke or bleeding risk and those with an
anticipated reduced efficacy of AFCA. This is a technically challenging
procedure with a significant risk of complications and should
only be carried out by clinicians with specific training and
appropriate experience in both AF ablation and LAAC procedure. In
addition to the implanter, an anaesthesiologist and an experienced
echocardiographer with specific training in supporting LAA
occlusion should be part of the procedural team.
This is a prospective observational study performed in a single centre
with consecutive patients and a relatively short follow-up. The small
sample of our study, which analyses the outcomes of a combined
procedure with the use of two different types of LAAO devices, as well as
the lack of control group, limits the power of the outcomes and do
not allow to draw definitive conclusions about efficacy and safety.
However, it describes our experience and the feasibility of this
novel strategy and could stimulate further multicentre trials to
clarify best practice and the safety profile of the combination of
AFCA and percutaneous LAAC in a single procedure.
We followed the recommendations of AF guidelines and all
patients were anticoagulated with acenocumarol until at least 3
months after the procedure, regardless of the type of LAAC device
Another limitation was the follow-up method of 48-h Holter
recordings. Asymptomatic arrhythmias or non-documented
symptomatic episodes might have been missed.
Finally, there are no scientific data directly comparing long-term
LAA occlusion with NOACs, or analysing the safety of NOACS
compared with OACs after LAAC. None of our patients were treated
with NOACS post-procedure, so our conclusions should be
limited to patients undergoing AFCA and percutaneous LAAC in a
single procedure and receiving anticoagulation with acenocumarol
for at least 3 months post-procedure.
The combination of AFCA and percutaneous LAAC in a single
procedure is a feasible strategy in patients with symptomatic
drug-refractory AF, high risk of stroke, and strict or relative
contraindication to OACs. Patient selection and management should be
carried out by a multidisciplinary team including a cardiologist and
other clinicians experienced in the management of patients with AF
at risk of stroke. There is a significant risk of periprocedural
complications, so the procedure should only be carried out by operators
with specific training and appropriate experience in both AF ablation
and LAAC procedure.
The authors thank E. Lilly for her excellent editing assistance and
G. Lo´ pez, C. D´ıaz, H. Janiasvilli, P. Ara, and A. Simo´ n-Ricart for
their great daily assistance.
Conflict of interest: I.G.-B. is proctor for Boston Scientific and
St.Jude Medical and has received consultant fees from St.Jude
Medical and from Boston Scientific. N.C. has received consultant
fees from St.Jude Medical and from Boston Scientific.
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