Catheterization and Cardiovascular Interventions 85:321–327 (2015)
Incomplete Left Atrial Appendage Occlusion and Thrombus Formation After Watchman Implantation Treated With Anticoagulation Followed by Further Transcatheter Closure With a Second-Generation Amplatzer Cardiac Plug (Amulet Device) Simon Cheung Chi Lam, MD, Stefan Bertog, MD, and Horst Sievert,* MD, PhD We report a case of incomplete left atrial appendage (LAA) closure after Watchman device (Atritech, Boston Scientific, Natrick, MA) implantation which subsequently developed a thrombus 3 years after the initial procedure. The thrombus resolved after a short period of anticoagulation with warfarin, and the LAA was successfully occluded with a second-generation Amplatzer Cardiac Plug (Amulet device, AGA, St Jude Medical, Minneapolis, MN). Incomplete LAA closure may be associated with increased risk of thrombus formation and further closure with a second device after a course of anticoagulation may be a reasonable and feasible strategy. VC 2014 Wiley Periodicals, Inc. Key words: left atrial appendage closure; fistula/shunts; transseptal cath
INTRODUCTION
Percutaneous left atrial appendage (LAA) closure has become an increasingly used procedure globally. However, incomplete closure remains a technical limitation of the procedure. There has been concern about that incomplete LAA sealing may paradoxically increase risk of embolic stroke because a pouch of stagnant blood flow may serve as a nidus for thrombus formation. We report a case of thrombus formation in a patient with incomplete LAA closure and describe our management strategy including temporary anticoagulation followed by transcatheter closure with a second LAA occluder device. CASE REPORT
An 86-year old male with chronic atrial fibrillation (CHADS2 score ¼ 5; CHA2DS2-VASc score ¼ 7) and high bleeding risk (HAS-BLED score ¼ 5, history of recurrent epistaxis and haematuria) underwent transcatheter LAA closure with a 30-mm Watchman device (Atritech, Boston Scientific, Natrick, MA). At the initial procedure, the Watchman device was successfully deployed but migrated slightly after deployment resulting in a 4-mm residual leak with a partially uncovered lobule. This LAA closure was, therefore, incomplete. At that time, the patient was reluctant to continue with long-term oral anticoagulation and opted for observation only. The leak has been static until 3 years later, C 2014 Wiley Periodicals, Inc. V
in which transesophageal echocardiography (TEE) demonstrated an increase in size of the residual leak with a diameter of 7 mm at the ostium measured by color doppler (Fig. 1). In addition, a 5 4 mm2 thrombus was noted within the residual pouch (Fig. 2). Management strategies were discussed with
CardioVascular Center Frankfurt, Frankfurt, Germany Conflict of interest: Simon Cheung Chi Lam, MD: no conflict of interests; Stefan Bertog, MD: no conflict of interests; Horst Sievert, MD, PhD: has ownership interest in or has received consulting fees, travel expenses or study honoraries from the following companies: Abbott, Access Closure, AGA, Angiomed, Arstasis, Atritech, Atrium, Avinger, Bard, Boston Scientific, Bridgepoint, Cardiac Dimensions, CardioKinetix, CardioMEMS, Coherex, Contego, CSI, EndoCross, EndoTex, Epitek, Evalve, ev3, FlowCardia, Gore, Guidant, Guided Delivery Systems, Inc., InSeal Medical, Lumen Biomedical, HLT, Kensey Nash, Kyoto Medical, Lifetech, Lutonix, Medinol, Medtronic, NDC, NMT, OAS, Occlutech, Osprey, Ovalis, Pathway, PendraCare, Percardia, pfm Medical, Rox Medical, Sadra, Sorin, Spectranetics, SquareOne, Trireme, Trivascular, Velocimed, Veryan. *Correspondence to: Horst Sievert, MD, PhD, CardioVascular Center Frankfurt, Seckbacher Landstrasse 65, Frankfurt 60389, Germany. E-mail: [email protected] Received 14 May 2013; Revision accepted 16 February 2014 DOI: 10.1002/ccd.25456 Published online 19 February 2014 in Wiley Online Library (wileyonlinelibrary.com)
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Fig. 1. TEE showing incomplete LAA closure with previous Watchman device.(a) Twodimensional (2D) TEE showed incomplete closure of LAA with residual flow at the LAA ostium detected by color doppler. (b) 3D TEE of the LAA ostium showed the Watchman device with compressed configuration (triangle) and a gap measured 7 3 10 mm2 (asterisk). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
Fig. 2. LAA thrombus. (a and b) TEE showed spontaneous echo contrast in LA with an echogenic mass measured 5 3 4 mm2 in LAA (arrows) next to the pre-existing Watchman Device (triangle) suspicious of thrombus. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
patient. Warfarin was restarted for 3 months (with careful monitoring of INR) and subsequently TEE demonstrated complete resolution of thrombus (Fig. 3A). Further transcatheter LAA closure with a second-generation Amplatzer Cardiac Plug (Amulet device, AGA, St Jude Medical, Minneapolis, MN) was performed.
Transseptal puncture was performed under echocardiographic guidance. Selective contrast injection via a pigtail catheter confirmed the position of the uncovered lobule and size of the landing zone (Fig. 4A and B). With a landing zone diameter of 22 mm (24 mm on TEE), a 28mm Amulet device was chosen and introduced via a 12 French delivery sheath (AMPLATZERTM TorqVueTM 45/
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Fig. 3. Reassessment after resumption of anticoagulation therapy for 3 months. (a) TEE showed complete resolution of LAA thrombus. The diameter of the landing zone for second device was 24 mm. (b) Fluoroscopic appearance (LAO 90 ) of the pre-existing Watchman device in a compressed configuration (arrows). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
Fig. 4. Cine angiogram of second LAA closure procedure. (a and b) Selective angiogram of LAA showed diameter of the landing zone as 22 mm (measured in RAO 30 /CAU 0 ). (c and d) 12 French delivery sheath was introduced into LAA with the distal lobe of the Amulet device deployed. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
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Lam et al.
Fig. 5. First attempt of deployment of the Amulet device. (a and b) Following the distal lobe, the proximal disc of the Amulet device was deployed, while the inner 0.01400 wire was still connected to the delivery system. (c and d) 2D TEE showed presence of the pre-existing Watchman Device (triangle); the disc of the Amulet device was in close contact in 45 view but
45 ). The distal lobe was first deployed followed by the proximal disc (Fig. 4C and D). The proximal disc was partially recaptured because of suboptimal position (due to the relative interaction between the preexisting Watchman device and the new Amulet device) and redeployed in a better position (Fig. 5). The device was well seated and all LAA lobules were well covered (Figs. 6 and 7). TEE showed no peridevice flow. The patient was well and discharged on the following day. Plavix 75 mg daily for 3 months and aspirin 6 months were recommended. Echocardiography at 6 weeks showed good position of both the devices with no peridevice leak.
have significant separation in 135 view (asterisk, corresponding to position in Fig. 5b) probably due to the pushing effect of pre-existing Watchman device. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary. com.]
DISCUSSION
Residual peridevice leak after transcatheter LAA occlusion is common. From the experience of the PROTECTAF study, 32% of patients had at least some degree of peridevice flow at 1 year. Particularly when the residual leak was small (defined as jet 5-mm width), there is no conclusive evidence to suggest its association with risk of future thromboembolism after stopping warfarin [1,2]. This case is an illustration of what may happen in a patient with previous incomplete LAA closure associated with a larger residual leak. Based on observations from surgical ligation, incomplete LAA closure increases blood stagnation
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Closure of Incomplete LAA Occlusion
325
Fig. 6. Final deployment of the Amulet device. (a to c) The Amulet device was partially recaptured with the disc subsequently redeployed in a more optimal position. (d) Final configuration of the Amulet device (asterisk) and the pre-existing Watchman Device (triangle). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
and higher velocity at the LAA ostium, which may paradoxically increase the risk of thromboembolic stroke [3,4]. According to one TEE study on incomplete surgical LAA ligation, spontaneous echocontrast was seen in the LAA in 50% of the patients and in most cases the spontaneous echocontrast was denser than that in the left atrium [5]. At the first procedure, the device migrated distally after release and was entrapped in the apex of one LAA lobule. We attempted to adjust the position of the device by use of a snare catheter; however, this had not been successful. As a result, there was a residual flow and a partially uncovered lobule. One option was to continue anticoagulation with warfarin. The patient was reluctant to pursue long-term anticoagulation because of the potential bleeding risk. Therefore, we
decided to monitor the patient closely with surveillance TEEs. The option of a repeated LAA closure procedure with a second device was also discussed with the patient but, initially, he preferred not to proceed. After an increase in size of the leak with associated thrombus formation and further discussion with the patient, he agreed to undergo the second procedure in attempt to achieve complete closure after thrombus resolution with a short period of warfarin therapy. Compared with the first generation, the secondgeneration Amplatzer Cardiac Plug (Amulet device) has a larger proximal disc to improve sealing, increased number of stabilizing wires for better anchoring, inverted disc end screw to reduce risk of thrombus formation, and a new delivery cable with an inner
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
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Lam et al.
Fig. 7. Final result. (a to c) 2D TEE on multiple views showed well-seated Amulet device on the pre-existing Watchman device (asterisk) with no peridevice leak. (d) 3D TEE showed the final result of the Amulet device deployment. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
0.01400 wire [6]. A proximal disc with a larger diameter could be beneficial in this setting because it offers better sealing of the incompletely closed LAA containing a pre-existing device. In addition, the new design with the new inner 0.01400 wire allows better assessment of the device before final deployment in which the device is free from tension of the delivery cable. It also facilitates recapture of the device for better positioning if necessary. This is especially helpful in challenging situations. There are potential technical difficulties in deploying a second occluder to an LAA with a pre-existing device. First, there is potential risk of dislodgement of the first device with repeated manipulation and repositioning. Manipulations within the LAA have to be very
careful and excessive movements should be avoided. In particular, the distal lobe of the second device should not be recaptured once it is deployed as it is in direct contact with the old device. Moreover, there is only limited space in the LAA due to the bulkiness of the old device, which may make the positioning of the second device difficult. Large sheaths and snare catheters should be readily available in the catheterization laboratory in case of device embolization. CONCLUSIONS
This case illustrated that incomplete closure of LAA may be associated with subsequent thrombus
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Closure of Incomplete LAA Occlusion
327
formation and further transcatheter closure with a second device after resolution of thrombus may be a feasible option.
3. Schneider B, Stollberger C, Sievers HH. Surgical closure of the left atrial appendage: A beneficial procedure? Cardiology 2005; 104:127–132.
REFERENCES
4. Rosenzweig BP, Katz E, Kort S, Schloss M, Kronzon I. Thromboembolus from a ligated left atrial appendage. J Am Soc Echocardiogr 2001;14:396–398.
1. Viles-Gonzalez JF, Kar S, Douglas P, Dukkipati S, et al. The clinical impact of incomplete atrial appendage closure with the Watchman device in patients with atrial fibrillation. J Am Coll Cardiol 2012;59:923–929. 2. Viles-Gonzalez JF, Reddy VY, Petru J, et al. Incomplete occlusion of the left atrial appendage with the percutaneous left atrial appendage transcatheter occlusion device is not associated with increased risk of stroke. J Interv Card Electrophysiol 2012;33:69– 75.
5. Katz E, Tsiamtsiour T, Applebaum R, Schwartzbard A, Tunick P, Kronzon I. Surgical atrial appendage ligation is frequently incomplete: A transesophageal echocardiographic study. J Am Coll Cardiol 2000;36:468–471. 6. Freixa X, Chan JLK, Tzikas A, Garceau P, Basmadjian A, Ibrahim R. The amplatzer cardiac plug 2 for left atrial appendage occlusion: novel features and first-in-man experience. EuroIntervention 2013;8:1094–1098.
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Incomplete Left Atrial Appendage Occlusion and Thrombus Formation After Watchman Implantation Treated With Anticoagulation Followed by Further Transcatheter Closure With a Second-Generation Amplatzer Cardiac Plug (Amulet Device) Simon Cheung Chi Lam, MD, Stefan Bertog, MD, and Horst Sievert,* MD, PhD We report a case of incomplete left atrial appendage (LAA) closure after Watchman device (Atritech, Boston Scientific, Natrick, MA) implantation which subsequently developed a thrombus 3 years after the initial procedure. The thrombus resolved after a short period of anticoagulation with warfarin, and the LAA was successfully occluded with a second-generation Amplatzer Cardiac Plug (Amulet device, AGA, St Jude Medical, Minneapolis, MN). Incomplete LAA closure may be associated with increased risk of thrombus formation and further closure with a second device after a course of anticoagulation may be a reasonable and feasible strategy. VC 2014 Wiley Periodicals, Inc. Key words: left atrial appendage closure; fistula/shunts; transseptal cath
INTRODUCTION
Percutaneous left atrial appendage (LAA) closure has become an increasingly used procedure globally. However, incomplete closure remains a technical limitation of the procedure. There has been concern about that incomplete LAA sealing may paradoxically increase risk of embolic stroke because a pouch of stagnant blood flow may serve as a nidus for thrombus formation. We report a case of thrombus formation in a patient with incomplete LAA closure and describe our management strategy including temporary anticoagulation followed by transcatheter closure with a second LAA occluder device. CASE REPORT
An 86-year old male with chronic atrial fibrillation (CHADS2 score ¼ 5; CHA2DS2-VASc score ¼ 7) and high bleeding risk (HAS-BLED score ¼ 5, history of recurrent epistaxis and haematuria) underwent transcatheter LAA closure with a 30-mm Watchman device (Atritech, Boston Scientific, Natrick, MA). At the initial procedure, the Watchman device was successfully deployed but migrated slightly after deployment resulting in a 4-mm residual leak with a partially uncovered lobule. This LAA closure was, therefore, incomplete. At that time, the patient was reluctant to continue with long-term oral anticoagulation and opted for observation only. The leak has been static until 3 years later, C 2014 Wiley Periodicals, Inc. V
in which transesophageal echocardiography (TEE) demonstrated an increase in size of the residual leak with a diameter of 7 mm at the ostium measured by color doppler (Fig. 1). In addition, a 5 4 mm2 thrombus was noted within the residual pouch (Fig. 2). Management strategies were discussed with
CardioVascular Center Frankfurt, Frankfurt, Germany Conflict of interest: Simon Cheung Chi Lam, MD: no conflict of interests; Stefan Bertog, MD: no conflict of interests; Horst Sievert, MD, PhD: has ownership interest in or has received consulting fees, travel expenses or study honoraries from the following companies: Abbott, Access Closure, AGA, Angiomed, Arstasis, Atritech, Atrium, Avinger, Bard, Boston Scientific, Bridgepoint, Cardiac Dimensions, CardioKinetix, CardioMEMS, Coherex, Contego, CSI, EndoCross, EndoTex, Epitek, Evalve, ev3, FlowCardia, Gore, Guidant, Guided Delivery Systems, Inc., InSeal Medical, Lumen Biomedical, HLT, Kensey Nash, Kyoto Medical, Lifetech, Lutonix, Medinol, Medtronic, NDC, NMT, OAS, Occlutech, Osprey, Ovalis, Pathway, PendraCare, Percardia, pfm Medical, Rox Medical, Sadra, Sorin, Spectranetics, SquareOne, Trireme, Trivascular, Velocimed, Veryan. *Correspondence to: Horst Sievert, MD, PhD, CardioVascular Center Frankfurt, Seckbacher Landstrasse 65, Frankfurt 60389, Germany. E-mail: [email protected] Received 14 May 2013; Revision accepted 16 February 2014 DOI: 10.1002/ccd.25456 Published online 19 February 2014 in Wiley Online Library (wileyonlinelibrary.com)
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Lam et al.
Fig. 1. TEE showing incomplete LAA closure with previous Watchman device.(a) Twodimensional (2D) TEE showed incomplete closure of LAA with residual flow at the LAA ostium detected by color doppler. (b) 3D TEE of the LAA ostium showed the Watchman device with compressed configuration (triangle) and a gap measured 7 3 10 mm2 (asterisk). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
Fig. 2. LAA thrombus. (a and b) TEE showed spontaneous echo contrast in LA with an echogenic mass measured 5 3 4 mm2 in LAA (arrows) next to the pre-existing Watchman Device (triangle) suspicious of thrombus. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
patient. Warfarin was restarted for 3 months (with careful monitoring of INR) and subsequently TEE demonstrated complete resolution of thrombus (Fig. 3A). Further transcatheter LAA closure with a second-generation Amplatzer Cardiac Plug (Amulet device, AGA, St Jude Medical, Minneapolis, MN) was performed.
Transseptal puncture was performed under echocardiographic guidance. Selective contrast injection via a pigtail catheter confirmed the position of the uncovered lobule and size of the landing zone (Fig. 4A and B). With a landing zone diameter of 22 mm (24 mm on TEE), a 28mm Amulet device was chosen and introduced via a 12 French delivery sheath (AMPLATZERTM TorqVueTM 45/
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Fig. 3. Reassessment after resumption of anticoagulation therapy for 3 months. (a) TEE showed complete resolution of LAA thrombus. The diameter of the landing zone for second device was 24 mm. (b) Fluoroscopic appearance (LAO 90 ) of the pre-existing Watchman device in a compressed configuration (arrows). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
Fig. 4. Cine angiogram of second LAA closure procedure. (a and b) Selective angiogram of LAA showed diameter of the landing zone as 22 mm (measured in RAO 30 /CAU 0 ). (c and d) 12 French delivery sheath was introduced into LAA with the distal lobe of the Amulet device deployed. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
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Lam et al.
Fig. 5. First attempt of deployment of the Amulet device. (a and b) Following the distal lobe, the proximal disc of the Amulet device was deployed, while the inner 0.01400 wire was still connected to the delivery system. (c and d) 2D TEE showed presence of the pre-existing Watchman Device (triangle); the disc of the Amulet device was in close contact in 45 view but
45 ). The distal lobe was first deployed followed by the proximal disc (Fig. 4C and D). The proximal disc was partially recaptured because of suboptimal position (due to the relative interaction between the preexisting Watchman device and the new Amulet device) and redeployed in a better position (Fig. 5). The device was well seated and all LAA lobules were well covered (Figs. 6 and 7). TEE showed no peridevice flow. The patient was well and discharged on the following day. Plavix 75 mg daily for 3 months and aspirin 6 months were recommended. Echocardiography at 6 weeks showed good position of both the devices with no peridevice leak.
have significant separation in 135 view (asterisk, corresponding to position in Fig. 5b) probably due to the pushing effect of pre-existing Watchman device. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary. com.]
DISCUSSION
Residual peridevice leak after transcatheter LAA occlusion is common. From the experience of the PROTECTAF study, 32% of patients had at least some degree of peridevice flow at 1 year. Particularly when the residual leak was small (defined as jet 5-mm width), there is no conclusive evidence to suggest its association with risk of future thromboembolism after stopping warfarin [1,2]. This case is an illustration of what may happen in a patient with previous incomplete LAA closure associated with a larger residual leak. Based on observations from surgical ligation, incomplete LAA closure increases blood stagnation
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Closure of Incomplete LAA Occlusion
325
Fig. 6. Final deployment of the Amulet device. (a to c) The Amulet device was partially recaptured with the disc subsequently redeployed in a more optimal position. (d) Final configuration of the Amulet device (asterisk) and the pre-existing Watchman Device (triangle). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
and higher velocity at the LAA ostium, which may paradoxically increase the risk of thromboembolic stroke [3,4]. According to one TEE study on incomplete surgical LAA ligation, spontaneous echocontrast was seen in the LAA in 50% of the patients and in most cases the spontaneous echocontrast was denser than that in the left atrium [5]. At the first procedure, the device migrated distally after release and was entrapped in the apex of one LAA lobule. We attempted to adjust the position of the device by use of a snare catheter; however, this had not been successful. As a result, there was a residual flow and a partially uncovered lobule. One option was to continue anticoagulation with warfarin. The patient was reluctant to pursue long-term anticoagulation because of the potential bleeding risk. Therefore, we
decided to monitor the patient closely with surveillance TEEs. The option of a repeated LAA closure procedure with a second device was also discussed with the patient but, initially, he preferred not to proceed. After an increase in size of the leak with associated thrombus formation and further discussion with the patient, he agreed to undergo the second procedure in attempt to achieve complete closure after thrombus resolution with a short period of warfarin therapy. Compared with the first generation, the secondgeneration Amplatzer Cardiac Plug (Amulet device) has a larger proximal disc to improve sealing, increased number of stabilizing wires for better anchoring, inverted disc end screw to reduce risk of thrombus formation, and a new delivery cable with an inner
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
326
Lam et al.
Fig. 7. Final result. (a to c) 2D TEE on multiple views showed well-seated Amulet device on the pre-existing Watchman device (asterisk) with no peridevice leak. (d) 3D TEE showed the final result of the Amulet device deployment. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]
0.01400 wire [6]. A proximal disc with a larger diameter could be beneficial in this setting because it offers better sealing of the incompletely closed LAA containing a pre-existing device. In addition, the new design with the new inner 0.01400 wire allows better assessment of the device before final deployment in which the device is free from tension of the delivery cable. It also facilitates recapture of the device for better positioning if necessary. This is especially helpful in challenging situations. There are potential technical difficulties in deploying a second occluder to an LAA with a pre-existing device. First, there is potential risk of dislodgement of the first device with repeated manipulation and repositioning. Manipulations within the LAA have to be very
careful and excessive movements should be avoided. In particular, the distal lobe of the second device should not be recaptured once it is deployed as it is in direct contact with the old device. Moreover, there is only limited space in the LAA due to the bulkiness of the old device, which may make the positioning of the second device difficult. Large sheaths and snare catheters should be readily available in the catheterization laboratory in case of device embolization. CONCLUSIONS
This case illustrated that incomplete closure of LAA may be associated with subsequent thrombus
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
Closure of Incomplete LAA Occlusion
327
formation and further transcatheter closure with a second device after resolution of thrombus may be a feasible option.
3. Schneider B, Stollberger C, Sievers HH. Surgical closure of the left atrial appendage: A beneficial procedure? Cardiology 2005; 104:127–132.
REFERENCES
4. Rosenzweig BP, Katz E, Kort S, Schloss M, Kronzon I. Thromboembolus from a ligated left atrial appendage. J Am Soc Echocardiogr 2001;14:396–398.
1. Viles-Gonzalez JF, Kar S, Douglas P, Dukkipati S, et al. The clinical impact of incomplete atrial appendage closure with the Watchman device in patients with atrial fibrillation. J Am Coll Cardiol 2012;59:923–929. 2. Viles-Gonzalez JF, Reddy VY, Petru J, et al. Incomplete occlusion of the left atrial appendage with the percutaneous left atrial appendage transcatheter occlusion device is not associated with increased risk of stroke. J Interv Card Electrophysiol 2012;33:69– 75.
5. Katz E, Tsiamtsiour T, Applebaum R, Schwartzbard A, Tunick P, Kronzon I. Surgical atrial appendage ligation is frequently incomplete: A transesophageal echocardiographic study. J Am Coll Cardiol 2000;36:468–471. 6. Freixa X, Chan JLK, Tzikas A, Garceau P, Basmadjian A, Ibrahim R. The amplatzer cardiac plug 2 for left atrial appendage occlusion: novel features and first-in-man experience. EuroIntervention 2013;8:1094–1098.
Catheterization and Cardiovascular Interventions DOI 10.1002/ccd. Published on behalf of The Society for Cardiovascular Angiography and Interventions (SCAI).
