Procedural Safety and Outcomes of Watchman vs. Amulet: A Meta-Analysis of Observational Studies
Presenter
Arslan Ahmed, MD, Creighton University School of Medicine, Omaha, NE
Arslan Ahmed, MD1, Arav Jhand, MBBS2, Rahul Dhawan, MD3, Jacqueline Saw, M.D., FSCAI4, Mohamad Alkhouli, M.D., FSCAI5, Matthew James Daniels, M.D., Ph.D., FSCAI6, Megan Coylewright, M.D., FSCAI7, Mauricio G. Cohen, M.D., FSCAI8, John W Schleifer, M.D.3 and Dr. Andrew Michael Goldsweig, MD, MS, FSCAI9, (1)Creighton University School of Medicine, Omaha, NE, (2)Mayo Clinic, Rochester, MN, (3)University of Nebraska Medical Center, Omaha, NE, (4)Vancouver General Hospital, Vancouver, BC, Canada, (5)Mayo Clinic - School of Medicine, Rochester, MN, (6)Manchester University Foundation NHS Trust, Altrincham, Manchester, United Kingdom, (7)Erlanger Health System, Chattanooga, TN, (8)Cleveland Clinic Florida, Pinecrest, FL, (9)University of Massachusetts - Baystate Medical Center, West Hartford, CT
Keywords: Left Atrial Appendage Closure (LAAC) and Structural Heart Disease (SHD)
Background:
Watchman (WM) is the only device approved for percutaneous left atrial appendage occlusion (LAAO) in the United States; other devices are available in Europe. We conducted a meta-analysis of observational studies comparing WM with Amulet (previously Amplatzer Cardiac Plug), the second most popular device.
Methods:
PubMed, Scopus and Google Scholar were searched systematically for studies comparing procedural outcomes of WM and Amulet. Data on patient and procedural characteristics and outcomes were collected. Procedural outcomes included procedure failure, death, tamponade, embolization, stroke and bleeding. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated using a random effects model.
Results:
11 studies with 2145 patients (WM 970, Amulet 1175) met inclusion criteria. Baseline characteristics including age, sex were not statistically different (Table 1).WM was associated with more procedural failure than Amulet [RR 2.10, 95% CI 1.15 - 3.85, p=0.02]. Procedural complication rates were similar between the 2 devices.
Conclusions:
Amulet is a safe alternative to WM with a higher technical success rate. Further prospective studies are indicated to validate our findings.
Table 1:
| Patient Characteristics |
| | Watchman (n = 970) | Amulet (n = 1175) | p-value |
| Age (mean ± SD), years | 74.2 ± 4.9 | 74.1 ± 5.3 | 0.96 |
| Female Sex, n (%) | 361 (37%) | 440 (37%) | 0.66 |
| CHA2DS2VASc Score (mean ± SD) | 4.2 ± 0.5 | 4.2 ± 0.4 | 0.91 |
| HAS-BLED Score (mean ± SD) | 3.2 ± 0.4 | 3.3 ± 0.5 | 0.86 |
| Procedure Characteristics |
| | Number of Studies Reporting the Characteristic | Standard Mean Difference (WM vs. Amulet) | 95% CI | p-value |
| Procedure Duration | 5/11 | -0.02 | -0.42 – 0.39 | 0.94 |
| Fluoroscopy Time | 5/11 | -0.44 | -1.26 – 0.38 | 0.29 |
| Length of Stay | 3/11 | -0.14 | -0.47 – 0.18 | 0.39 |
| Procedural Outcomes |
| Outcome | Number of Studies Reporting the Outcome | Watchman | Amulet | RR | 95% CI | p-value |
| Procedure Failure | 11/11 | 3.4 % | 1.4 % | 2.10 | 1.15 – 3.85 | 0.02 |
| Death | 9/11 | 0.5 % | 0.4 % | 1.04 | 0.29 – 3.73 | 0.95 |
| Pericardial Effusion | 6/11 | 4.9 % | 3.5 % | 1.12 | 0.61 – 2.02 | 0.72 |
| Cardiac Tamponade | 7/11 | 1.9 % | 2.0 % | 1.19 | 0.55 – 2.56 | 0.66 |
| Device Embolization | 6/11 | 0.5 % | 1.1 % | 0.54 | 0.19 – 1.55 | 0.25 |
| Stroke | 10/11 | 0.2 % | 0.2 % | 1.52 | 0.27 – 8.60 | 0.64 |
| Major Bleeding | 7/11 | 1.0 % | 1.6 % | 0.48 | 0.12 – 1.98 | 0.31 |
| Vascular Complications | 9/11 | 2.7 % | 2.8 % | 0.58 | 0.32 – 1.02 | 0.06 |