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Journal of the American College of Cardiology  2013 by the American College of Cardiology Foundation Published by Elsevier Inc. CLINICAL RESEARCH Vol. 62, No. 2, 2013 ISSN 0735-1097/$36.00 http://dx.doi.org/10.1016/j.jacc.2013.02.089 Mini-Focus: Left Atrial Closure in Atrial Fibrillation Percutaneous Left Atrial Appendage Closure With the AMPLATZER Cardiac Plug Device in Patients With Nonvalvular Atrial Fibrillation and Contraindications to Anticoagulation Therapy Marina Urena, MD,* Josep Rodés-Cabau, MD,* Xavier Freixa, MD,y Jacqueline Saw, MD,z John G. Webb, MD,x Mélanie Freeman, MD,x Eric Horlick, MD,k Mark Osten, MD,k Albert Chan, MD,{ Jean-Francois Marquis, MD,# Jean Champagne, MD,* Réda Ibrahim, MDy Quebec City, Quebec; Montreal, Quebec; Vancouver, British Columbia; Toronto, Ontario; and Ottawa, Ontario, Canada Objectives The aim of this study was to evaluate the results associated with left atrial appendage closure (LAAC) with the AMPLATZER Cardiac Plug (ACP) (St. Jude Medical, Minneapolis, Minnesota) in patients with nonvalvular atrial fibrillation and absolute contraindications to anticoagulation therapy. Background Few data exist on the late outcomes after LAAC in patients with absolute contraindications to warfarin. Methods A total of 52 patients with nonvalvular atrial fibrillation underwent LAAC with the ACP device in 7 Canadian centers. Most patients received short-term (1 to 3 months) dual-antiplatelet therapy after the procedure and singleantiplatelet therapy thereafter. A transesophageal echocardiography was performed in 74% of patients at the 6-month follow-up. No patient was lost to follow-up (12 months in all patients). Results The mean age and median (interquartile range) CHADS2 score were 74  8 years and 3 (2 to 4), respectively. The procedure was successful in 98.1% of the patients, and the main complications were device embolization (1.9%) and pericardial effusion (1.9%), with no cases of periprocedural stroke. At a mean follow-up of 20  5 months, the rates of death, stroke, systemic embolism, pericardial effusion, and major bleeding were 5.8%, 1.9%, 0%, 1.9%, and 1.9%, respectively. The presence of mild peridevice leak was observed in 16.2% of patients at the 6-month follow-up as evaluated by transesophageal echocardiography. There were no cases of device thrombosis. Conclusions In patients with nonvalvular atrial fibrillation at high risk of cardioembolic events and absolute contraindications to anticoagulation, LAAC using the ACP device followed by dual-/single-antiplatelet therapy was associated with a low rate of embolic and bleeding events after a mean follow-up of 20 months. No cases of severe residual leak or device thrombosis were observed at the 6-month follow-up. (J Am Coll Cardiol 2013;62:96–102) ª 2013 by the American College of Cardiology Foundation From the *Quebec Heart & Lung Institute, Quebec City, Quebec, Canada; yMontreal Heart Institute, Montreal, Quebec, Canada; zVancouver General Hospital, Vancouver, British Columbia, Canada; xSt. Paul’s Hospital, Vancouver, British Columbia, Canada; kToronto General Hospital, Toronto, Ontario, Canada; {Royal Columbian Hospital, Vancouver, British Columbia, Canada; and the #Ottawa Heart Institute, Ottawa, Ontario, Canada. Drs. Rodés-Cabau, Webb, Horlick, Osten, and Ibrahim are consultants for St. Jude Medical. Dr. Saw is a proctor for St. Jude Medical. Dr. Ibrahim is a proctor for St. Jude Medical and Gore Medical; and has financial relationships (lectures and advisory boards) with Boston Scientific and Medtronic. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. Manuscript received September 13, 2012; revised manuscript received February 6, 2013, accepted February 14, 2013. Anticoagulation is contraindicated in as many as 10% of the patients with atrial fibrillation due to major bleeding (1) and as many as 50% of patients discontinue anticoagulation therapy 3 years after initiation of treatment (2). The See page 119 PROTECT-AF (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) trial (3) showed that percutaneous left atrial appendage closure (LAAC) with the WATCHMAN device JACC Vol. 62, No. 2, 2013 July 9, 2013:96–102 Urena et al. Outcomes After Amplatzer Closure Plug to anticoagulation therapy (9,10), but no data exist on the outcomes of such patients beyond 1-year follow-up. The objective of this study was therefore to evaluate the results associated with LAAC using the ACP device at a follow-up of 1 year in patients with NVAF and contraindications to anticoagulation therapy. Methods 97 Abbreviations and Acronyms ACP = AMPLATZER Cardiac Plug LAA = left atrial appendage LAAC = left atrial appendage closure MAE = major adverse event(s) NVAF = nonvalvular atrial fibrillation TEE = transesophageal echocardiography TIA = transient ischemic Figure 1 AMPLATZER Cardiac Plug Device White arrow ¼ distal lobe; long black arrow ¼ proximal disk; short black arrows ¼ stabilizing wires. (Boston Scientific, Natick, Massachusetts) was not inferior to warfarin treatment in patients with nonvalvular atrial fibrillation (NVAF) and no contraindications to anticoagulation. However, published results of LAAC in patients with contraindications to anticoagulation have mainly been limited to small series of patients using the PLAATO (Percutaneous Left Atrial Appendage Transcatheter Occlusion) device (ev3 Inc., Plymouth, Minnesota), which is no longer available (4–8). The AMPLATZER Cardiac Plug (ACP) device (St. Jude Medical, Minneapolis, Minnesota) consists of a selfexpandable device with a distal lobe and proximal disk connected by an articulating waist (Figs. 1 and 2). Two recent studies reported the feasibility of LAAC with the ACP device in patients with NVAF and contraindications Figure 2 attack The study included a total of 52 consecutive patients with NVAF, contraindications to anticoagulation therapy, and an estimated risk of annual stroke of 2%, as determined by a CHADS2 score 1 (11) or CHA2DS2-VASc score 2 (12) underwent LAAC with the ACP device at 7 Canadian centers. Device and procedure. The ACP device characteristics and LAAC procedure were previously described in detail (13). Transthoracic echocardiography was performed 24 h after the procedure in all patients. Procedural success was defined as successful implantation of the ACP device in the left atrial appendage (LAA) with no severe residual leak. Major adverse events (MAEs) at the index hospitalization and during the follow-up period were defined according to the Valve Academic Research Consortium criteria (14) and included cardiovascular death, device embolization, stroke, systemic embolism, myocardial infarction, cardiac tamponade, major bleeding, and the need for cardiovascular surgery. Antithrombotic therapy. Heparin (100 U/kg) was administered during the procedure in all cases, and the final dose Fluoroscopic Image of the AMPLATZER Cardiac Plug Device Fluoroscopic image of the AMPLATZER Cardiac Plug device after successful left atrial appendage closure. Note the compression of the lobe by the left atrial appendage wall (black arrows). JACC Vol. 62, No. 2, 2013 July 9, 2013:96–102 Urena et al. Outcomes After Amplatzer Closure Plug 98 was adjusted to achieve an activated clotting time >250 s. No anticoagulation therapy was administered after the procedure. Antiplatelet therapy consisting of aspirin (80 to 325 mg/24 h) plus clopidogrel (75 mg/24 h), or aspirin or clopidogrel alone was given according to the operators’ discretion for 30 to 180 days after the procedure, after which singleantiplatelet therapy was given. Follow-up. Follow-up was performed by clinical visits or phone contact at 1, 6, and 12 months and yearly thereafter. Transesophageal echocardiography (TEE) was performed in 37 patients (74% of the patients at risk) at the 6-month follow-up. The presence of device thrombosis and residual intra- or peridevice leak were evaluated. Residual leak was defined as mild if intra- or peridevice flow was observed with a jet width 1 and <3 mm and severe if 3 mm (15). Statistical analysis. Continuous variables are expressed as mean  SD or median (25th to 75th percentiles) depending on distribution of the data. Categorical variables were compared using a chi-square test or Fisher exact test, and numerical variables using the Student t test or Wilcoxon Table 1 Baseline Characteristics of the Study Population (N ¼ 52) Age, yrs 74  8 Female 22 (42.3) Body mass index, kg/m2 27 (24–30) Atrial fibrillation type Chronic 25 (48.1) Paroxysmal 27 (51.9) Hypertension 48 (92.3) Diabetes mellitus 21 (40.4) Thromboembolic events Stroke 29 (55.8) Transient ischemic attack Coronary artery disease 3 (5.8) 26 (50.0) Peripheral vascular disease Previous heart failure 6 (11.5) 10 (19.2) Previous bioprosthesis eGFR, ml/min Previous bleeding 3 (5.8) rank sum test. Comparisons between observed and expected rates of thromboembolic and bleeding events were assessed using binomial tests. Kaplan-Meier curves were used to analyze cumulative outcomes at 2-year follow-up. All analyses were conducted using the SAS statistical package version 9.2 (SAS Institute Inc., Cary, North Carolina). Results Baseline characteristics and procedural findings of the study population are shown in Table 1. Reasons for anticoagulation therapy contraindications are shown in Table 2. Procedural results and in-hospital outcomes. The main procedural findings and acute results are shown in Table 3. The procedure was successful in all patients but 1 (98.1%). One patient had a device embolization a few minutes after implantation, most likely related to device undersizing. The device was successfully retrieved percutaneously with no complications. During the hospitalization period, there were no deaths or strokes. One patient had a transient ischemic attack (TIA) 24 h after the procedure while on aspirin plus clopidogrel therapy. TEE showed the absence of intracardiac thrombi and complete LAA sealing. Follow-up. The mean follow-up was 20  5 months (12 months in all patients). The late clinical outcomes are shown in Table 4. A total of 3 patients (5.8%) died during the follow-up period, and no death was related to the device. One patient had a lacunar stroke 16 months after the procedure, with complete recovery and no sequelae. The patient was receiving clopidogrel at the time of the event. Another patient had a TIA at the 6-month follow-up while on aspirin plus clopidogrel therapy. TEE showed the absence of cardiac thrombi and complete LAA sealing. One patient had a cardiac tamponade requiring pericardiocentesis 1 month after the procedure without evidence of perforation by TEE and computed tomography. Another patient experienced major bleeding related to angiodysplasia. The main clinical characteristics of patients with MAEs during the follow-up 72.2 (51.1–81.5) 47 (90.4) No. of bleeding episodes 1 (1–2) Previous liver disease 2 (3.8) Table 2 Reasons for Anticoagulation Therapy Contraindication (N ¼ 52) INR lability 4 (7.7) CHADS2 score 3 (2–4) CHA2DS2-VASc score 5 (4–6) Intracranial hemorrhage 18 (34.6) 4 (3–4) Gastrointestinal bleeding 12 (23.1) HAS-BLED score Spontaneous hematoma of abdominal muscles 7 (13.5) 10 (19.2) Otorhinolaryngological 4 (7.7) 24 (46.2) Respiratory 3 (5.8) Baseline antithrombotic treatment None Aspirin Clopidogrel Aspirin þ clopidogrel 3 (5.8) 15 (28.8) Warfarin 2 (3.8) Recurrent severe hematuria 1 (1.9) Ophthalmological 1 (1.9) Recurrent hemarthrosis 1 (1.9) International normalized ratio lability 2 (3.8) 60 (50–60) High risk of fall 1 (1.9) 8 (15.3) Warfarin allergy 1 (1.9) Severe anemia 1 (1.9) Other anticoagulant LVEF, % Bleeding 0 LVEF 40% Values are mean  SD, n (%), or median (25th to 75th percentiles). INR ¼ international normalized ratio; LVEF ¼ left ventricular ejection fraction. Values are n (%). JACC Vol. 62, No. 2, 2013 July 9, 2013:96–102 Table 3 99 Urena et al. Outcomes After Amplatzer Closure Plug Procedural and In-Hospital Findings Table 4 Procedural findings Follow-Up Results 20  5 Median of follow-up, months LAA diameter by TEE at 45 , mm 18  4 Antithrombotic therapy at last follow-up LAA diameter by TEE at 120 , mm 20  4 Aspirin LAA diameter by angiography, mm 20  3 Clopidogrel Device size, mm 18 1 (1.9) 32 (61.5) 6 (11.5) Aspirin þ clopidogrel 9 (17.3) None 5 (9.6) 20 9 (17.3) Device embolization 0 (0) 22 16 (30.8) Cardiac tamponade 1 (1.9) 24 11 (21.2) Major bleeding 1 (1.9) 26 8 (15.4) Transient ischemic attack 1 (1.9) 28 4 (7.7) Stroke 1 (1.9) 30 3 (5.8) Systemic embolism 0 (0) 1.16  0.11 Ratio device/LAA ostium* Procedural success Death 51 (98.1) In-hospital outcomes Pericardial effusion 0 (0) Major bleedingy 2 (3.8) Device embolization 1 (1.9) Myocardial infarction 0 (0) Systemic embolism 0 (0) Transient ischemic attack 1 (1.9) Stroke 0 (0) Death 0 (0) MAEsz 3 (5.8) Hospitalization length, days 1 (1–1) 1 (1.9) 16.2%. A lower left ventricular ejection fraction was associated with the occurrence of a new peridevice leak at the 6-month follow-up (p ¼ 0.016) (Table 6). None of the patients with residual leaks had a cardioembolic event. There were no cases of device thrombosis or late device embolization. Discussion LAAC with the ACP device: acute results. LAAC with the ACP device was associated with a high rate of procedural success (98.1%) and low rate of periprocedural complications (device embolization, 1.9%; TIA, 1.9%; pericardial effusion, 1.9%). These results compared with those of previous studies on LAAC in patients with contraindications to anticoagulation therapy are shown in Table 7. Follow-up. This study showed that a strategy of LAAC followed by antiplatelet therapy was associated with a low rate of embolic events (stroke, 1.9%; systemic embolism, 0%) at a mean follow-up of 20 months, lower than the event rate expected on the basis of the characteristics of the study population (Fig. 3). Of note, avoiding a short-term period of anticoagulation after LAAC was not associated with any embolic event or device thrombosis, suggesting that the use period are shown in Table 5. The rates of cumulative observed versus expected MAEs are shown in Figure 3. The KaplanMeier survival curves are shown in Figure 4. Echocardiography data. Immediately after the procedure, a mild intradevice and peridevice leak were observed in 1 (1.9%) and 6 (11.5%) patients, respectively, and all but 1 leak had disappeared on TEE performed at the 6-month follow-up. A total of 5 patients with no leak immediately after the procedure had a mild peridevice leak as determined by TEE at the 6-month follow-up resulting in a global incidence of peridevice leaks at follow-up of Individual Characteristics of Patients With Major Adverse Events at Follow-Up CHADS2 Score CHA2DS2-VASc Score HAS-BLED Score Prosthesis Size, mm 67 4 7 5 69 2 3 2 Age, yrs 3 (5.8) Cardiovascular or neurologic death* Values are mean  SD or n (%). *Patient died of heart failure. Values are mean  SD, n (%), or median (25th to 75th percentiles). *As measured by angiography. yDue to access site hematoma in all cases. zIncluded cardiovascular death, device embolization, stroke, systemic embolism, myocardial infarction, cardiac tamponade, major bleeding, and need for cardiovascular surgery. LAA ¼ left atrial appendage; MAEs ¼ major adverse event(s); TEE ¼ transesophageal echocardiography. Table 5 Overall Peridevice Leak Antithrombotic Therapy 22 Mild Aspirin Major bleeding 1 26 No Aspirin þ clopidogrel TIA 5 MAEs Timing, months 73 2 4 2 18 No Aspirin þ clopidogrel Cardiac tamponade 1 78 5 8 5 22 No Aspirin CVD* 8 80 4 7 5 24 No Aspirin Non-CVD 81 3 4 4 28 Unknown Clopidogrel Stroke 16 Clopidogrel Non-CVD 22 *Patient died of heart failure. CVD ¼ cardiovascular death; MAEs ¼ major adverse event(s); TIA ¼ transient ischemic attack; other abbreviations as in Table 3. 3 100 Figure 3 JACC Vol. 62, No. 2, 2013 July 9, 2013:96–102 Urena et al. Outcomes After Amplatzer Closure Plug Expected Versus Observed Thromboembolic and Bleeding Events Expected annual rates of stroke and thromboembolic (stroke, TIA, systemic embolism) and bleeding events in the study population based on CHADS2 (11), CHA2DS2-VASc (21) and HAS-BLED (22) scores, respectively, compared with the cumulative observed rates during the entire study period. The observed annual rates of stroke and thromboembolic and bleeding events were 87%, 66%, and 61%, respectively, lower than expected. However, actual observed event rates with anticoagulation therapy were lower than expected in the PROTECT AF trial (3), the only randomized trial comparing anticoagulation and left atrial appendage closure, and, thus, real rates of stroke and thromboembolic and bleeding events in this population in the absence of left atrial appendage closure might differ from these estimates. These results will have to be confirmed by randomized trials. *Included patients to whom aspirin had been prescribed. yPatients on aspirin were included. TIA ¼ transient ischemic attack. of percutaneous LAAC may be a therapeutic alternative to avoid thromboembolic events in patients with absolute contraindications to anticoagulation therapy. Also, the use of single-antiplatelet therapy was associated with a lowerthan-expected rate of bleeding, with only 1 serious Table 6 Figure 4 Survival Curves After Percutaneous Left Atrial Appendage Closure With the AMPLATZER Cardiac Plug Device Kaplan-Meier survival curves at 2-year follow-up showing the percentage of patients free of death, stroke, and major bleeding. hemorrhagic event occurring during the follow-up period (1.9%) (Fig. 3). However, 2 cases of asymptomatic ACP device thrombosis were previously reported at 3 and 6 months after LAAC in patients on single-antiplatelet treatment (16), highlighting the need for larger studies to further evaluate the incidence and clinical relevance of device thrombosis in such patients. Data on LAAC in patients with contraindications to anticoagulation therapy have been limited to a few series of patients who had undergone LAAC with the PLAATO device (4–8), no longer available, the recently presented ASAP (ASA Plavix Feasibility Study with Watchman Echocardiographic Findings According to the Presence of New Peridevice Leaks at 6-Month Follow-Up Overall (N ¼ 37) Paroxysmal AF Peridevice Leak (n ¼ 5) No Peridevice Leak (n ¼ 32) p Value 18 (58.6) 4 (80.0) 14 (43.8) 0.180 LA diameter, mm 45  11 48  9 43  13 0.475 LA volume, mm3/cm2 38  14 38  10 37  17 0.943 LAA ostium width by TEE at 45 , mm 18  3 17  2 19  3 0.184 LAA ostium width by TEE at 120 , mm 20  3 18  2 20  3 0.290 LAA ostium width by angiography, mm Device size, mm 18–20 20  3 21  3 20  3 0.654 22 (22–26) 22 (22–24) 22 (22–26) 0.758 6 (16.2) 0 6 (18.8) 22 14 (37.8) 3 (60.0) 11 (34.4) 24 8 (21.6) 2 (40.0) 6 (18.8) 26 7 (18.9) 0 7 (21.9) 28–30 2 (5.4) 0 0.548 2 (6.3) Ratio device/LAA ostium* 1.16  0.13 1.12  0.16 1.17  0.13 0.390 LVEF, % 60 (50–60) 37 (27–52) 60 (50–60) 0.016 Values are n (%), mean  SD, or median (25th to 75th percentiles). *As measured by angiography. AF ¼ atrial fibrillation; LA ¼ left atrium; LVEF ¼ left ventricular ejection fraction; other abbreviations as in Table 3. 2.2 d 3.4 0y 0 2.2 12 0 2.2 0 0 0 95.5 89 Bartus et al.* (18) LARIAT 0 ACP 52 Urena et al., current study *Although the study included patients considered to be poor candidates or ineligible for warfarin therapy and/or warfarin failures, as many as 55% of the patients were on warfarin therapy at 1-year follow-up. yOne patient (1.1%) had a thrombus in the left atrium at a site distant from the occlusion site. ACP ¼ AMPLATZER Cardiac Plug. 0 5.8 5.7 1.9 0 0 1.9 20 0 1.9 1.9 d 98.1 0 0 d d 0 0 d d 5 0 d d 13 0 0 3.5 0 0 1.4 1.4 5.0 2.1 0 92.3 95.0 20 ACP 143 Park et al. (10) Lam et al. (9) ACP 6.0 1.3 1.3 4.0 0.6 2.7 14 d 1.3 1.3 d 94.7 150 Reddy et al. (ASAP trial) (17) WATCHMAN 180 Bayard et al. (8) PLAATO 0 d 5.0 3.9 d 3.3 0.6 d 1.7 10 1.1 3.3 0.6 15.1 90.0 d d d 0 5.0 0 0 d 0 0 1.4 24 40 0 1.4 0 5.0 0 1.4 d 0 1.4 0 98.6 90.0 PLAATO PLAATO 73 20 Park et al. (6) Ussia et al. (7) 5.4 26.5 d d 1.8 1.6 0 0.9 d d 12.5 1.8 10 45 1.6 0.9 1.8 1.6 d d d d 0 0 97.3 93.9 PLAATO PLAATO 64 111 Ostermayer et al. (4) Device n Block et al. (5) Pericardial Tamponade, % Device Thrombosis, % Stroke, % Success, % Systemic Embolism, % Device Embolism, % Pericardial Tamponade, % Mortality, % Average Follow-Up, months Stroke, % Systemic Embolism, % Results at Follow-Up Acute Results Urena et al. Outcomes After Amplatzer Closure Plug First Author/Study (Ref. #) Table 7 Acute Results and Clinical Events at Latest Follow-Up of Patients Undergoing Percutaneous Closure of Left Atrial Appendage in Patients With Contraindication for Anticoagulation Therapy Bleeding, % Mortality, % JACC Vol. 62, No. 2, 2013 July 9, 2013:96–102 101 Left Atrial Appendage Closure Technology) (17) and the limited experience with the LARIAT device (18). Consistent with the results of the present study, LAAC followed by antiplatelet therapy was associated with a low rate of cerebrovascular events at follow-up (Table 7). Residual leaks. Mild residual leaks after percutaneous LAAC have been reported in as many as 32% and 75% of the patients after WATCHMAN and PLAATO device implantation, respectively (15,19). The low rate of residual leak observed in this study (16.2%) may be related to the double-disk structure of the ACP device with a larger proximal disk that covers the LAA orifice from the left atrium side, contributing to a better sealing of the LAA. Of note, in as many as 5 patients (13.5%) with no leak immediately after the procedure, a new peridevice leak developed over time. This was previously reported using the WATCHMAN device (20) and might be related to incomplete device endothelialization or some degree of device undersizing without periprocedural residual leak due to LAA contraction immediately after the implantation. Also, the fact that a low left ventricular ejection fraction was associated with a peridevice leak suggests that changes in the left atrial dimensions over time might play a role in the occurrence of these late leaks. Importantly, the presence of mild residual leaks was not associated with any cardioembolic event, and this was consistent with the results of previous studies (15). Study limitations. Although this is the study with the longest follow-up in patients undergoing LAAC with the ACP device to date, the sample size was limited. The rate of expected events was based on historical controls, which have not been validated in the present population. The possibility of a type I error cannot be ruled out. These results will therefore have to be confirmed by randomized, controlled trials. TEE examinations at follow-up were incomplete, not analyzed in an echocardiography core laboratory, and only performed once, which may have limited the possibility of thrombus device detection. Finally, although clinical data were prospectively collected at each center, no pre-specified case report form or event adjudication committee was used. Conclusions In patients with NVAF at high risk of cardioembolic events and with contraindications to anticoagulation therapy, percutaneous LAAC with the ACP device followed by dual-/single-antiplatelet therapy was associated with a low rate of cardioembolic and bleeding complications at a mean follow-up of 20 months. LAAC was successful in >98% of patients, with a small proportion having mild residual leak, and no cases of severe residual leak or device thrombosis were observed. However, these results do not provide sufficient evidence to state that LAAC without anticoagulation provides sufficient safety to recommend this approach until adequate data from clinical trials can be 102 Urena et al. Outcomes After Amplatzer Closure Plug obtained. 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Key Words: AMPLATZER Cardiac Plug - anticoagulation atrial fibrillation - percutaneous closure of left atrial appendage.