• Users Online: 258
  • Home
  • Print this page
  • Email this page
Home About us Editorial board Ahead of print Current issue Search Archives Submit article Instructions Subscribe Contacts Login 

 Table of Contents  
Year : 2017  |  Volume : 2  |  Issue : 1  |  Page : 22-28

Evolution of left atrial appendage exclusion

Department of Cardiovascular Diseases, Mayo Clinic Hospital, Arizona, Phoenix, AZ, USA

Date of Web Publication19-Jun-2017

Correspondence Address:
Dan Sorajja
Division of Cardiovascular Diseases, Mayo Clinic Hospital, 5777 E Mayo Boulevard, Phoenix, AZ, 85054
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/2352-4197.208457

Rights and Permissions

Atrial fibrillation is independently associated with an increased risk of thromboembolic stroke. While anticoagulants decrease this risk, they also carry a substantial risk of bleeding. Most left atrial thrombi arise from the left atrial appendage (LAA), which has led to several investigations into surgical and percutaneous methods of LAA exclusion for stroke reduction. The PubMed database was queried, and over 400 articles were considered for inclusion in this review. Of the surgical methods of LAA exclusion, complete excision is the most effective. Other methods, including ligation and stapling, may be incomplete and associated with left atrial thrombus formation. Surgical LAA exclusion has been commonly performed during mitral valve surgery although it has not been shown to prevent stroke in many retrospective studies. In patients unable to take warfarin, several percutaneous LAA exclusion devices have been studied, including the PLAATO system, Amplatzer Cardiac Plug (ACP), Watchman device, and Lariat. Both the ACP and Watchman have shown a significant stroke reduction and improved procedural safety with greater experience. The Lariat ligates the LAA using a combined endocardial and epicardial approach but is currently associated with substantial procedural risks. With better patient selection for the different options of LAA exclusion, thromboembolic stroke protection can be maximized with fewer complication risks.

Keywords: Atrial fibrillation, exclusion, left atrial appendage, occlusion, stroke

How to cite this article:
Abrich VA, Sorajja D. Evolution of left atrial appendage exclusion. Int J Heart Rhythm 2017;2:22-8

How to cite this URL:
Abrich VA, Sorajja D. Evolution of left atrial appendage exclusion. Int J Heart Rhythm [serial online] 2017 [cited 2022 Jan 24];2:22-8. Available from: https://www.ijhronline.org/text.asp?2017/2/1/22/208457

  Introduction Top

Atrial fibrillation (AF) was first found to independently increase the risk of stroke by 4.8-fold, based on data from the Framingham study in 1991.[1] The mechanism is widely accepted to be related to stasis of blood in the left atrium, which predisposes to thrombus formation and resultant systemic embolization to the cerebral circulation.[2] The majority of left atrial thrombi have been found to originate in the left atrial appendage (LAA), which accounts for 91% of thrombi in nonvalvular AF and 57% of thrombi in rheumatic AF.[3] The risk of stroke can be calculated based on the CHA2 DS2–VASc score.[4] Anticoagulation with warfarin was found to decrease this stroke risk by 64%.[5] Novel oral anticoagulants, such as dabigatran, rivaroxaban, and apixaban, are even more effective than warfarin at reducing the risk of ischemic stroke and have a better safety profile. Compared to warfarin, together they are associated with an 18% reduction in stroke or systemic embolism, 9% reduction in mortality, and 49% reduction in hemorrhagic stroke.[6] Not surprisingly, the administration of warfarin and novel oral anticoagulants has emerged as first-line therapy in the management of AF.[7] Unfortunately, anticoagulants are inherently associated with risks of bleeding, which may be substantial and occasionally life-threatening.[2] As such, exclusion of the LAA has been investigated as an alternative to anticoagulation for reducing the stroke risk associated with AF. In this review, the different modalities of LAA exclusion will be covered, ranging from surgical exclusion during cardiac surgery to the use of dedicated percutaneous occlusion devices.

  Methods Top

We queried the PubMed database for articles that contained the search phrases “left atrial appendage occlusion” and “left atrial appendage exclusion” and reviewed more than 400 abstracts for inclusion in this review. Publication dates of included articles ranged from July 02, 1949 to February 01, 2016. We chose to include randomized controlled trials, case–control studies, and case series dealing with the topics of surgical or percutaneous LAA exclusion. A particular focus was placed on cerebrovascular event outcomes and procedural safety. Articles were saved and organized using EndNote X4 software (Thomson Reuters, Philadelphia, Pennsylvania). Reported event rates were normalized to adjusted annual event rates.

Surgical Exclusion

Surgical LAA exclusion was first performed concomitantly during surgery for mitral stenosis.[8],[9] Although this procedure has been shown to be safe, its implementation depends on the surgeon and institution.[3] Surgical LAA exclusion is now indicated in patients with AF undergoing cardiac surgery for other primary indications, according to current management guidelines for AF.[7] Successful LAA exclusion is confirmed by transesophageal echocardiography (TEE), with overall success rates among studies varying from 40% to 90%.[10],[11],[12],[13],[14] Common methods of LAA exclusion include complete excision of the LAA (45%–83% success rate), exclusion through ligation (23%–90% success rate), and exclusion through stapling (0%–72% success rate) [Figure 1]. Left atrial thrombus or spontaneous echo contrast has been documented in up to 50% of patients with incomplete exclusion following ligation or stapling and in up to 17% of patients following complete excision of the LAA. More recently, surgical LAA exclusion with an epicardial clip system (Atriclip, AtriCure, Inc., Cincinnati, Ohio) has been associated with a 100% successful closure rate during open heart surgery and with a 71% successful closure rate during minithoracotomy [Figure 2].[15],[16]
Figure 1: Stapled excision of the left atrial appendage. (a) The stapler is loaded with pericardial strips. (b) The left atrial appendage is excised, and area beneath the buttressed staple line is examined (From Gillinov AM, et al. Stapled excision of the left atrial appendage. J Thorac CV Surg 2005;129 (3):679-680. Used with permission).

Click here to view
Figure 2: Atriclip for exclusion of the left atrial appendage (From Salzberg SP, et al. left atrial appendage clip occlusion: Early clinical results. J Thorac Cardiovasc Surg 2010; 139:1269-74. Used with permission). (a) Reusable Miltex deployment tool. LAA clip is loaded onto the jaws of this tool. (b) LAA mobilized within the clip (1) near the pulmonary veins (2) and pulmonary artery (3) with operator's hand (4) mobilizing the heart.

Click here to view

The effectiveness of surgical LAA exclusion during cardiac surgery for reducing the risk of stroke has been evaluated in multiple retrospective studies, with mostly disappointing results. Surgical LAA exclusion done concomitantly with mitral valve surgery has been studied in multiple heterogeneous series comprising between 50 and 812 patients.[13],[16],[17],[18],[19] In these studies, the prevalence of AF ranged from 61.3% to 85.9%, with LAA exclusion being performed in 27.9%–100% of patients. Adjusted annual cerebrovascular event rates in these patients were 0.6%–3.4% during mean follow-up periods of 3.6–5.8 years.[13],[16],[17],[19] LAA exclusion was not found to prevent stroke in most of these studies;[13],[17],[18],[19] however, one study found the absence of LAA exclusion to be a predictor of embolic events.[16] Interestingly, another study that included patients who underwent either mitral valve or coronary artery bypass graft (CABG) surgery showed that surgical LAA exclusion prevented postoperative cerebrovascular events for patients with CHA2 DS2–VASc scores of two or less.[17]

Aside from mitral valve surgery, surgical LAA exclusion is routinely performed during the Maze procedure for surgical ablation of AF.[20] In a study of 265 patients undergoing the Maze procedure, the adjusted, annual cerebrovascular event rate was 0.3% during a mean follow-up of 3.6 years. In other studies, the Maze procedure has been associated with successful LAA closure, and its omission was a predictor of late stroke occurrence.[10],[18] Isolated, thoracoscopic LAA exclusion has also been investigated: one small series of 15 patients undergoing isolated LAA exclusion through ligation or stapling had an annual adjusted stroke rate of 0% during a mean follow-up of 1.3 years, whereas another small series of thirty patients undergoing complete LAA excision had an annual adjusted stroke rate of 3.8% during a mean follow-up of 3.5 years.[21],[22]

More recently, interest has grown for performing LAA exclusion concomitantly during CABG surgery. The safety and efficacy of this practice were prospectively evaluated in the Left Atrial Appendage Occlusion Study (LAAOS) I and II, two small, randomized pilot studies comprising 77 and 51 patients, respectively.[15],[23] Adjusted annual stroke rates in the LAA occlusion arms were 3.6% for LAAOS I and 3.8% for LAAOS II during mean follow-up periods of 13 months and 12 months, respectively. In comparison, the adjusted annual stroke rates for the non-LAA occlusion arms were 0% for LAAOS I and 12.0% for LAAOS II. These studies paved the way for LAAOS III, an ongoing multicenter, randomized controlled trial. LAAOS III is recruiting 4700 patients with AF undergoing CABG, who will be randomized to LAA exclusion versus no LAA exclusion.[24] The primary outcome of stroke or systemic embolism will be analyzed at a mean follow-up of 4 years. This will be the largest study to date to determine whether or not surgical LAA exclusion reduces the risk of stroke in patients with AF.

  Percutaneous Exclusion Top

Percutaneous LAA exclusion devices were developed to provide thromboembolic protection in patients with AF who have contraindications to anticoagulation, embolic events while taking anticoagulants, or intolerance to anticoagulants [Table 1].[25] The first device developed was the percutaneous LAA transcatheter occlusion system (PLAATO, ev3 Inc., Plymouth, Minnesota, USA); however, its development was discontinued by the manufacturer in 2007 because of financial reasons. The device consisted of a self-expanding nitinol cage that was covered by a nonpermeable, polytetrafluoroethylene membrane designed to promote endothelialization,[26] and patients who had the device implanted were required to take aspirin [Figure 3]a.[25] The PLAATO system was evaluated in multiple series comprising between 15 and 180 patients.[26],[27],[28],[29],[30],[31] Success rates for acute closure varied from 90% to 100%. Periprocedural complications reported in these studies included a 0.6%–1.4% incidence of device embolization [28],[29] as well as a 1.6%–6.7% incidence of pericardial effusion.[26],[27],[28],[29],[30],[31] Adjusted annual cerebrovascular event rates were 0%–5.5% during mean follow-up periods between 9.8 and 45 months.[27],[28],[29],[30],[31] The PLAATO device was associated with a 65% reduction in stroke risk relative to the predicted risk of stroke based on the CHADS2 score.[27],[28]
Table 1: Comparison between different percutaneous methods of left atrial appendage exclusion

Click here to view
Figure 3: Percutaneous exclusion of the left atrial appendage. (a) PLAATO System; (b) Amplatzer Cardiac Plug; (c) Watchman; (d) Lariat Suture Delivery Device (From Patel TK, Yancy CW, Knight BP. Left atrial appendage exclusion for stroke prevention in atrial fibrillation. Cardiol Res Pract 2012; Article ID 610827, 2012. doi: 10.1155/2012/610827. Used with permission).

Click here to view

The Amplatzer septal occluder (St. Jude Medical, St. Paul, Minnesota, USA), originally designed for closing atrial septal defects, was the next percutaneous device that was tested for occluding the LAA; the device was used in a series of 16 patients, in which one of these patients had device embolization [Figure 3]b.[32] The Amplatzer septal occluder was subsequently adapted for LAA occlusion as the Amplatzer Cardiac Plug (ACP, St. Jude Medical). The ACP consists of a lobe connected to a disc; the lobe anchors the device in the neck of the LAA, and the disc covers the LAA orifice.[25] After the device is implanted, dual antiplatelet therapy (aspirin and clopidogrel) is administered for 1–6 months, after which aspirin alone is prescribed. Success rates for acute closure varied from 95% to 98% in multiple series comprising between 20 and 137 patients.[33],[34],[35],[36] Periprocedural complications reported in these studies included pericardial effusion (1.7%–3.5% incidence),[33],[34],[35],[36],[37] device embolization (0%–1.9% incidence),[33],[34],[35],[36],[37] coronary artery embolism (0.7%–5% incidence),[33],[34] and cerebrovascular events (1.9%–2.5% incidence).[33],[35],[37] One study showed a 14.2% incidence of thrombi with the ACP although all thrombi resolved after treatment with enoxaparin.[36] During mean follow-up periods ranging from 12.7 to 21 months, adjusted annual cerebrovascular event rates were 0%–1.7%.[34],[35],[36] A second generation device, the Amplatzer Amulet (St. Jude Medical) has been shown to have comparable efficacy to the ACP but with fewer peridevice leaks.[38]

The Watchman (Boston Scientific Corporation, Natick, Massachusetts) was the next percutaneous LAA occlusion device to be developed [Figure 3]c. It consists of a nitinol cage with a row of fixation barbs around the surface, which are covered by a permeable polymeric membrane.[25] Unlike previous percutaneous devices, the Watchman was evaluated in a randomized controlled trial. PROTECT AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) was a multicenter, unblinded clinical trial that randomized 707 patients in a 2:1 ratio to two arms: the device versus warfarin.[39] The successful implantation rate was 88%. Patients who had the Watchman implanted were required to take warfarin with aspirin for the first 45 days after the implant, followed by dual antiplatelet therapy for 4.5 months, and then aspirin alone thereafter. At a mean follow-up of 3.8 years, the Watchman was superior to warfarin, demonstrating a 40% reduction in the primary composite endpoint of stroke, systemic embolism, and cardiovascular death. This reduction was mainly driven by reductions in the incidence of hemorrhagic stroke (0.6% in the device arm, 4.0% in the warfarin arm) and cardiovascular death (3.7% in the device arm, 9.0% in the warfarin arm). Although no significant difference in the incidence of ischemic stroke was shown in the trial (5.2% in the device arm, 4.1% in the warfarin arm), a meta-analysis of 2406 trial and registry patients later showed the Watchman to be associated with a small increase in ischemic strokes offset by a relatively larger reduction in hemorrhagic strokes.[40]

Procedure-related complications in PROTECT AF occurred in the device arm within the first 7 days and included pericardial effusion with tamponade (4.8% incidence), ischemic stroke (1.3% incidence), and device embolization (0.6% incidence).[39] Improved procedure-related outcomes have since been shown in the subsequent randomized PREVAIL (Watchman Left Atrial Appendage Closure Device in Patients with Atrial Fibrillation Versus Long-Term Warfarin Therapy) trial, as well as the Continued Access Protocol and EWOLUTION registries, mitigating initial safety concerns [Table 2]. With improved operator experience over a learning curve, successful device implantation rates were higher (95%–98.5%), whereas periprocedural complication rates were lower than those observed in the PROTECT AF trial. These included serious pericardial effusions (0.5%–2.2% incidence), device embolization (0%–0.5% incidence), and ischemic stroke (0%–0.4% incidence).[41],[42],[43] Moreover, alternative blood thinner regimens after implantation have been investigated. Replacement of warfarin during the first 45 days after device deployment with novel oral anticoagulants and dual antiplatelet therapy has been shown to be safe and effective.[44],[45],[46] Nevertheless, device thrombosis has been documented in patients with clopidogrel resistance.[47]
Table 2: Procedural complications following Watchman implantation

Click here to view

Subsequent to the Watchman, the Lariat Suture Delivery Device (SentreHeart, Inc., Redwood City, California) was developed [Figure 3]d. The Lariat incorporates an epicardial approach to exclude the LAA. To deploy the Lariat, the operator accesses the pericardial space and guides a snare and suture to the base of the LAA over a rail comprised a set of magnet-tipped epicardial and endocardial guidewires, thus ligating the LAA.[48] Following the procedure, antiplatelet and anticoagulant therapy regimens are heterogeneous among patients, consisting of aspirin monotherapy, dual antiplatelet therapy, or oral anticoagulation.[49],[50],[51],[52] Successful closure rates have been reported to range from 93% to 96% in multiple series comprising between 27 and 154 patients.[49],[50],[51],[52] Procedural complications in these studies included LAA perforation (0.6%–9.8% incidence),[49],[50],[51],[52] pericardial effusions (1.1%–43.9% incidence),[49],[50],[51],[52] and pericarditis (2.2%–22% incidence).[49],[50],[52] One study reported a 3.7% incidence of periprocedural stroke [52] while another study reported a 4.8% incidence of left atrial thrombi.[51] The adjusted annual ischemic cerebrovascular event rates ranged from 0% to 4.2% during mean follow-up periods of four to 12 months.[49],[50],[51]

In addition to safety and ischemic events, the effect of percutaneous LAA exclusion on atrial electrical activity is also a subject of interest. Necrosis of the LAA after ligation with the Lariat has been reported to decrease the duration, amplitude, and dispersion of the P wave on the electrocardiogram, which may represent reverse electrical atrial remodeling.[53] However, the combination of pulmonary vein isolation and LAA closure did not show a reduction in AF after 2 years in a small randomized trial of 89 patients.[54] In fact, the short-term burden of postprocedure AF was higher in those patients who underwent the combination procedure. Nevertheless, the recently approved aMAZE trial (Percutaneous Alternative to the Maze Procedure for the Treatment of Persistent or Long-standing Persistent Atrial Fibrillation) will prospectively gauge the efficacy of the Lariat in conjunction with pulmonary vein isolation for maintenance of sinus rhythm in a larger cohort of approximately 600 patients with AF, with stroke being a secondary endpoint.[55]

  Imaging Top

Imaging studies are important for confirming correct device placement and for checking for peridevice leaks. TEE has been used in most studies of percutaneous devices; however, advanced three-dimensional imaging with multidetector computed tomography (MDCT) has become an important adjunct. Compared with TEE, MDCT can provide more accurate data for sizing and for optimal placement of percutaneous occlusion devices, which can reduce procedural complications and the occurrence of peridevice leakage.[56],[57] Moreover, MDCT has revealed substantial heterogeneity of the LAA and its ostium, allowing for several distinct morphological classifications that have implications on patient selection and procedural planning.[58] Cardiac magnetic resonance and real-time three-dimensional TEE have emerged as alternatives to MDCT.[59],[60] Recently, three-dimensional printing of a patient's LAA from a CT image has helped plan the implantation of a Watchman device, which may have interesting implications as the technology becomes more widely available in hospitals.[61]

  Conclusion Top

LAA exclusion has evolved over the past several decades from being a procedure only performed concomitantly during cardiac surgery to now including several dedicated percutaneous procedure options intended to replace anticoagulation for the treatment of patients with AF. With most surgical data being retrospective, the results of the ongoing LAAOS III will more definitively determine the benefit of surgical LAA exclusion. Of the percutaneous devices, the Watchman is currently the only one the US Food and Drug Administration approved after it showed clinical benefit in randomized controlled trials.[62] Eligible patients must have a CHA2 DS2–VASc score ≥3 and a contraindication for long-term anticoagulation although they should be able to take warfarin for the short-term.[63] Whereas implantation of the Watchman has fewer complications with improved operator experience, the Lariat is still associated with substantial procedural safety concerns. The routine deployment of the Lariat during pulmonary vein isolation procedures will depend on the efficacy and safety results from the ongoing aMAZE trial.[55] With better patient selection for the different options of LAA exclusion, thromboembolic stroke protection for patients with AF can be maximized with fewer complication risks.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Wolf PA, Abbott RD, Kannel WB. Atrial fibrillation as an independent risk factor for stroke: The Framingham Study. Stroke 1991;22:983-8.  Back to cited text no. 1
Crystal E, Connolly SJ. Role of oral anticoagulation in management of atrial fibrillation. Heart 2004;90:813-7.  Back to cited text no. 2
Blackshear JL, Odell JA. Appendage obliteration to reduce stroke in cardiac surgical patients with atrial fibrillation. Ann Thorac Surg 1996;61:755-9.  Back to cited text no. 3
Lip GY, Nieuwlaat R, Pisters R, Lane DA, Crijns HJ. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: The euro heart survey on atrial fibrillation. Chest 2010;137:263-72.  Back to cited text no. 4
Hart RG, Pearce LA, Aguilar MI. Meta-analysis: Antithrombotic therapy to prevent stroke in patients who have nonvalvular atrial fibrillation. Ann Intern Med 2007;146:857-67.  Back to cited text no. 5
Dogliotti A, Paolasso E, Giugliano RP. Novel oral anticoagulants in atrial fibrillation: A meta-analysis of large, randomized, controlled trials vs. warfarin. Clin Cardiol 2013;36:61-7.  Back to cited text no. 6
January CT, Wann LS, Alpert JS, Calkins H, Cigarroa JE, Cleveland JC Jr., et al.2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol 2014;64:e1-76.  Back to cited text no. 7
Madden JL. Resection of the left auricular appendix; a prophylaxis for recurrent arterial emboli. J Am Med Assoc 1949;140:769-72.  Back to cited text no. 8
Bailey CP, Olsen AK, Keown KK, Nichols HT, Jamison WL. Commissurotomy for mitral stenosis; technique for prevention of cerebral complications. J Am Med Assoc 1952;149:1085-91.  Back to cited text no. 9
Kanderian AS, Gillinov AM, Pettersson GB, Blackstone E, Klein AL. Success of surgical left atrial appendage closure: Assessment by transesophageal echocardiography. J Am Coll Cardiol 2008;52:924-9.  Back to cited text no. 10
Katz ES, Tsiamtsiouris T, Applebaum RM, Schwartzbard A, Tunick PA, Kronzon I. Surgical left atrial appendage ligation is frequently incomplete: A transesophageal echocardiograhic study. J Am Coll Cardiol 2000;36:468-71.  Back to cited text no. 11
Cullen MW, Stulak JM, Li Z, Powell BD, White RD, Ammash NM, et al. Left atrial appendage patency at cardioversion after surgical left atrial appendage intervention. Ann Thorac Surg 2016;101:675-81.  Back to cited text no. 12
Healey JS, Crystal E, Lamy A, Teoh K, Semelhago L, Hohnloser SH, et al. Left Atrial Appendage Occlusion Study (LAAOS): Results of a randomized controlled pilot study of left atrial appendage occlusion during coronary bypass surgery in patients at risk for stroke. Am Heart J 2005;150:288-93.  Back to cited text no. 13
García-Fernández MA, Pérez-David E, Quiles J, Peralta J, García-Rojas I, Bermejo J, et al. Role of left atrial appendage obliteration in stroke reduction in patients with mitral valve prosthesis: A transesophageal echocardiographic study. J Am Coll Cardiol 2003;42:1253-8.  Back to cited text no. 14
Emmert MY, Puippe G, Baumüller S, Alkadhi H, Landmesser U, Plass A, et al. Safe, effective and durable epicardial left atrial appendage clip occlusion in patients with atrial fibrillation undergoing cardiac surgery:First long-term results from a prospective device trial. Eur J Cardiothorac Surg 2014;45:126-31.  Back to cited text no. 15
Ad N, Massimiano PS, Shuman DJ, Pritchard G, Holmes SD. New approach to exclude the left atrial appendage during minimally invasive cryothermic surgical ablation. Innovations (Phila) 2015;10:323-7.  Back to cited text no. 16
Orszulak TA, Schaff HV, Pluth JR, Danielson GK, Puga FJ, Ilstrup DM, et al. The risk of stroke in the early postoperative period following mitral valve replacement. Eur J Cardiothorac Surg 1995;9:615-9.  Back to cited text no. 17
Bando K, Kobayashi J, Hirata M, Satoh T, Niwaya K, Tagusari O, et al. Early and late stroke after mitral valve replacement with a mechanical prosthesis: Risk factor analysis of a 24-year experience. J Thorac Cardiovasc Surg 2003;126:358-64.  Back to cited text no. 18
Almahameed ST, Khan M, Zuzek RW, Juratli N, Belden WA, Asher CR, et al. Left atrial appendage exclusion and the risk of thromboembolic events following mitral valve surgery. J Cardiovasc Electrophysiol 2007;18:364-6.  Back to cited text no. 19
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;118:833-40.  Back to cited text no. 20
Blackshear JL, Johnson WD, Odell JA, Baker VS, Howard M, Pearce L, et al. Thoracoscopic extracardiac obliteration of the left atrial appendage for stroke risk reduction in atrial fibrillation. J Am Coll Cardiol 2003;42:1249-52.  Back to cited text no. 21
Ohtsuka T, Ninomiya M, Nonaka T, Hisagi M, Ota T, Mizutani T. Thoracoscopic stand-alone left atrial appendectomy for thromboembolism prevention in nonvalvular atrial fibrillation. J Am Coll Cardiol 2013;62:103-7.  Back to cited text no. 22
Whitlock RP, Vincent J, Blackall MH, Hirsh J, Fremes S, Novick R, et al. Left Atrial Appendage Occlusion Study II (LAAOS II). Can J Cardiol 2013;29:1443-7.  Back to cited text no. 23
Whitlock R, Healey J, Vincent J, Brady K, Teoh K, Royse A, et al. Rationale and design of the Left Atrial Appendage Occlusion Study (LAAOS) III. Ann Cardiothorac Surg 2014;3:45-54.  Back to cited text no. 24
Proietti R, Joza J, Arensi A, Levi M, Russo V, Tzikas A, et al. Novel nonpharmacologic approaches for stroke prevention in atrial fibrillation: Results from clinical trials. Med Devices (Auckl) 2015;8:103-14.  Back to cited text no. 25
Sievert H, Lesh MD, Trepels T, Omran H, Bartorelli A, Della Bella P, et al. Percutaneous left atrial appendage transcatheter occlusion to prevent stroke in high-risk patients with atrial fibrillation: Early clinical experience. Circulation 2002;105:1887-9.  Back to cited text no. 26
Ostermayer SH, Reisman M, Kramer PH, Matthews RV, Gray WA, Block PC, et al. Percutaneous left atrial appendage transcatheter occlusion (PLAATO system) to prevent stroke in high-risk patients with non-rheumatic atrial fibrillation: Results from the international multi-center feasibility trials. J Am Coll Cardiol 2005;46:9-14.  Back to cited text no. 27
Bayard YL, Omran H, Neuzil P, Thuesen L, Pichler M, Rowland E, et al. PLAATO (Percutaneous Left Atrial Appendage Transcatheter Occlusion) for prevention of cardioembolic stroke in non-anticoagulation eligible atrial fibrillation patients: Results from the European PLAATO study. EuroIntervention 2010;6:220-6.  Back to cited text no. 28
Park JW, Leithäuser B, Gerk U, Vrsansky M, Jung F. Percutaneous left atrial appendage transcatheter occlusion (PLAATO) for stroke prevention in atrial fibrillation: 2-year outcomes. J Invasive Cardiol 2009;21:446-50.  Back to cited text no. 29
Block PC, Burstein S, Casale PN, Kramer PH, Teirstein P, Williams DO, et al. Percutaneous left atrial appendage occlusion for patients in atrial fibrillation suboptimal for warfarin therapy: 5-year results of the PLAATO (Percutaneous Left Atrial Appendage Transcatheter Occlusion) Study. JACC Cardiovasc Interv 2009;2:594-600.  Back to cited text no. 30
Ussia GP, Mulè M, Cammalleri V, Scarabelli M, Barbanti M, Immè S, et al. Percutaneous closure of left atrial appendage to prevent embolic events in high-risk patients with chronic atrial fibrillation. Catheter Cardiovasc Interv 2009;74:217-22.  Back to cited text no. 31
Meier B, Palacios I, Windecker S, Rotter M, Cao QL, Keane D, et al. Transcatheter left atrial appendage occlusion with Amplatzer devices to obviate anticoagulation in patients with atrial fibrillation. Catheter Cardiovasc Interv 2003;60:417-22.  Back to cited text no. 32
Park JW, Bethencourt A, Sievert H, Santoro G, Meier B, Walsh K, et al. Left atrial appendage closure with Amplatzer cardiac plug in atrial fibrillation: Initial European experience. Catheter Cardiovasc Interv 2011;77:700-6.  Back to cited text no. 33
Lam YY, Yip GW, Yu CM, Chan WW, Cheng BC, Yan BP, et al. Left atrial appendage closure with AMPLATZER cardiac plug for stroke prevention in atrial fibrillation: Initial Asia-Pacific experience. Catheter Cardiovasc Interv 2012;79:794-800.  Back to cited text no. 34
Urena M, Rodes-Cabau J, Freixa X, Saw J, Webb JG, Freeman M, et al. Percutaneous left atrial appendage closure with the AMPLATZER cardiac plug device in patients with nonvalvular atrial fibrillation and contraindications to anticoagulation therapy. J Am Coll Cardiol 2013;62:96-102.  Back to cited text no. 35
López-Mínguez JR, Eldoayen-Gragera J, González-Fernández R, Fernández-Vegas C, Fuentes-Cañamero ME, Millán-Nuñez V, et al. Immediate and one-year results in 35 consecutive patients after closure of left atrial appendage with the Amplatzer cardiac plug. Rev Esp Cardiol (Engl Ed) 2013;66:90-7.  Back to cited text no. 36
Nietlispach F, Gloekler S, Krause R, Shakir S, Schmid M, Khattab AA, et al. Amplatzer left atrial appendage occlusion: Single center 10-year experience. Catheter Cardiovasc Interv 2013;82:283-9.  Back to cited text no. 37
Abualsaud A, Freixa X, Tzikas A, Chan J, Garceau P, Basmadjian A, et al. Side-by-side comparison of LAA occlusion performance with the amplatzer cardiac plug and amplatzer amulet. J Invasive Cardiol 2016;28:34-8.  Back to cited text no. 38
Reddy VY, Sievert H, Halperin J, Doshi SK, Buchbinder M, Neuzil P, et al. Percutaneous left atrial appendage closure vs. warfarin for atrial fibrillation: A randomized clinical trial. JAMA 2014;312:1988-98.  Back to cited text no. 39
Holmes DR Jr., Doshi SK, Kar S, Price MJ, Sanchez JM, Sievert H, et al. Left atrial appendage closure as an alternative to warfarin for stroke prevention in atrial fibrillation: A patient-level meta-analysis. J Am Coll Cardiol 2015;65:2614-23.  Back to cited text no. 40
Reddy VY, Holmes D, Doshi SK, Neuzil P, Kar S. Safety of percutaneous left atrial appendage closure: Results from the watchman left atrial appendage system for embolic protection in patients with AF (PROTECT AF) clinical trial and the continued access registry. Circulation 2011;123:417-24.  Back to cited text no. 41
Boersma LV, Schmidt B, Betts TR, Sievert H, Tamburino C, Teiger E, et al. Implant success and safety of left atrial appendage closure with the WATCHMAN device: Peri-procedural outcomes from the EWOLUTION registry. Eur Heart J 2016; doi:10.1093/eurheartj/ehv730. Epub 2016 Jan 27.  Back to cited text no. 42
Holmes DR Jr., Kar S, Price MJ, Whisenant B, Sievert H, Doshi SK, et al. Prospective randomized evaluation of the watchman left atrial appendage closure device in patients with atrial fibrillation versus long-term warfarin therapy: The PREVAIL trial. J Am Coll Cardiol 2014;64:1-12.  Back to cited text no. 43
Bösche LI, Afshari F, Schöne D, Ewers A, Mügge A, Gotzmann M. Initial experience with novel oral anticoagulants during the first 45 days after left atrial appendage closure with the watchman device. Clin Cardiol 2015;38:720-4.  Back to cited text no. 44
Reddy VY, Mobius-Winkler S, Miller MA, Neuzil P, Schuler G, Wiebe J, et al. Left atrial appendage closure with the watchman device in patients with a contraindication for oral anticoagulation: The ASAP study (ASA Plavix Feasibility Study with Watchman Left Atrial Appendage Closure Technology). J Am Coll Cardiol 2013;61:2551-6.  Back to cited text no. 45
Meincke F, Schmidt-Salzmann M, Kreidel F, Kuck KH, Bergmann MW. New technical and anticoagulation aspects for left atrial appendage closure using the WATCHMAN® device in patients not taking warfarin. EuroIntervention 2013;9:463-8.  Back to cited text no. 46
Ketterer U, D'Ancona G, Siegel I, Ortak J, Ince H, Kische S. Percutaneous left atrial appendage occlusion: Device thrombosis in clopidogrel non-responders. Int J Cardiol 2016;204:196-7.  Back to cited text no. 47
Bartus K, Bednarek J, Myc J, Kapelak B, Sadowski J, Lelakowski J, et al. Feasibility of closed-chest ligation of the left atrial appendage in humans. Heart Rhythm 2011;8:188-93.  Back to cited text no. 48
Bartus K, Han FT, Bednarek J, Myc J, Kapelak B, Sadowski J, et al. Percutaneous left atrial appendage suture ligation using the LARIAT device in patients with atrial fibrillation: Initial clinical experience. J Am Coll Cardiol 2013;62:108-18.  Back to cited text no. 49
Miller MA, Gangireddy SR, Doshi SK, Aryana A, Koruth JS, Sennhauser S, et al. Multicenter study on acute and long-term safety and efficacy of percutaneous left atrial appendage closure using an epicardial suture snaring device. Heart Rhythm 2014;11:1853-9.  Back to cited text no. 50
Price MJ, Gibson DN, Yakubov SJ, Schultz JC, Di Biase L, Natale A, et al. Early safety and efficacy of percutaneous left atrial appendage suture ligation: Results from the U.S. transcatheter LAA ligation consortium. J Am Coll Cardiol 2014;64:565-72.  Back to cited text no. 51
Stone D, Byrne T, Pershad A. Early results with the LARIAT device for left atrial appendage exclusion in patients with atrial fibrillation at high risk for stroke and anticoagulation. Catheter Cardiovasc Interv 2015;86:121-7.  Back to cited text no. 52
Kawamura M, Scheinman MM, Lee RJ, Badhwar N. Left atrial appendage ligation in patients with atrial fibrillation leads to a decrease in atrial dispersion. J Am Heart Assoc 2015;4. pii: e001581.  Back to cited text no. 53
Romanov A, Pokushalov E, Artemenko S, Yakubov A, Stenin I, Kretov E, et al. Does left atrial appendage closure improve the success of pulmonary vein isolation? Results of a randomized clinical trial. J Interv Card Electrophysiol 2015;44:9-16.  Back to cited text no. 54
Lee RJ, Lakkireddy D, Mittal S, Ellis C, Connor JT, Saville BR, et al. Percutaneous alternative to the maze procedure for the treatment of persistent or long-standing persistent atrial fibrillation (aMAZE trial): Rationale and design. Am Heart J 2015;170:1184-94.  Back to cited text no. 55
van Rosendael PJ, Katsanos S, van den Brink OW, Scholte AJ, Trines SA, Bax JJ, et al. Geometry of left atrial appendage assessed with multidetector-row computed tomography: Implications for transcatheter closure devices. EuroIntervention 2014;10:364-71.  Back to cited text no. 56
Chung H, Jeon B, Chang HJ, Han D, Shim H, Cho IJ, et al. Predicting peri-device leakage of left atrial appendage device closure using novel three-dimensional geometric CT analysis. J Cardiovasc Ultrasound 2015;23:211-8.  Back to cited text no. 57
Wang Y, Di Biase L, Horton RP, Nguyen T, Morhanty P, Natale A. Left atrial appendage studied by computed tomography to help planning for appendage closure device placement. J Cardiovasc Electrophysiol 2010;21:973-82.  Back to cited text no. 58
Nucifora G, Faletra FF, Regoli F, Pasotti E, Pedrazzini G, Moccetti T, et al. Evaluation of the left atrial appendage with real-time 3-dimensional transesophageal echocardiography: Implications for catheter-based left atrial appendage closure. Circ Cardiovasc Imaging 2011;4:514-23.  Back to cited text no. 59
Mohrs OK, Wunderlich N, Petersen SE, Pottmeyer A, Kauczor HU. Contrast-enhanced CMR in patients after percutaneous closure of the left atrial appendage: A pilot study. J Cardiovasc Magn Reson 2011;13:33.  Back to cited text no. 60
Otton JM, Spina R, Sulas R, Subbiah RN, Jacobs N, Muller DW, et al. Left atrial appendage closure guided by personalized 3D-printed cardiac reconstruction. JACC Cardiovasc Interv 2015;8:1004-6.  Back to cited text no. 61
Romero J, Natale A, Engstrom K, Di Biase L. Left atrial appendage isolation using percutaneous (endocardial/epicardial) devices: Pre-clinical and clinical experience. Trends Cardiovasc Med 2016;26:182-99.  Back to cited text no. 62
Decision Memo for Percutaneous Left Atrial Appendage (LAA) Closure Therapy (CAG-00445N). Centers for Medicare and Medicaid Services. Available from: https://www.cms.gov/medicare-coverage-database/details/nca-decision-memo.aspx?NCAId = 281. [Last accessed on 2016 Nov 19].  Back to cited text no. 63


  [Figure 1], [Figure 2], [Figure 3]

  [Table 1], [Table 2]

This article has been cited by
1 Hemodynamic effects of left atrial appendage occlusion
Esseim Sharma,Eirini Apostolidou,Wasiq Sheikh,Anshul Parulkar,M. Bilal Ahmed,Fabio V. Lima,Brian D. McCauley,Kevin Kennedy,Antony F. Chu
Journal of Interventional Cardiac Electrophysiology. 2021;
[Pubmed] | [DOI]
2 Atrial Fibrillation for the Neurologist: Preventing both Ischemic and Hemorrhagic Strokes
Elif Gokcal,Marco Pasi,Marc Fisher,M. Edip Gurol
Current Neurology and Neuroscience Reports. 2018; 18(2)
[Pubmed] | [DOI]


Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

  In this article
Percutaneous Exc...
Article Figures
Article Tables

 Article Access Statistics
    PDF Downloaded378    
    Comments [Add]    
    Cited by others 2    

Recommend this journal