WATCHMAN and Amplatzer Amulet for left atrial appendage occlusion: a systematic review and meta-analysis

WATCHMAN and Amplatzer Amulet devices are an effective alternative to oral anticoagulation for left atrial appendage closure (LAAC) in non-valvular atrial fibrillation (NVAF) patients. This study aims to compare their safety and efficacy.

This systematic review and meta-analysis followed PRISMA guidelines. PubMed, Embase, and ScienceDirect, were searched from inception to May 2025 for comparative studies in NVAF patients. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using random-effects models. Heterogeneity was assessed via I ² statistic; statistical significance was at P < 0.05.

Sixteen studies were included. No significant differences were found in ischemic stroke (RR 1.10, 95% CI 0.83-1.46; P = 0.51; I ² = 0%), all-cause mortality (RR 0.92, 95% CI 0.75-1.14; P = 0.45; I ² = 0%), major bleeding (RR 1.11, 95% CI 0.90-1.38; P = 0.33; I ² = 0%), minor bleeding (RR 1.11, 95% CI 0.76-1.61; P = 0.59; I ² = 22%), cardiac mortality (RR 0.86, 95% CI 0.39-1.93; P = 0.72; I ² = 51%), major procedure-related complications (RR 0.93, 95% CI 0.44-1.96; P = 0.55; I ² = 62%), cardiac tamponade (RR 0.57, 95% CI 0.25-1.29; P = 0.18; I ² = 30%), device embolization (RR 0.74, 95% CI 0.30-1.86; P = 0.53; I ² = 0%), vascular complications (RR 0.74, 95% CI 0.34-1.52; P = 0.38; I ² = 0%), or peridevice leak (RR 0.88, 95% CI 0.56-1.36; P = 0.55; I ² = 77%). WATCHMAN showed higher device thrombosis (RR 1.73, 95% CI 1.20-2.49; P = 0.003; I ² = 0%) but lower pericardial effusion (RR 0.47, 95% CI 0.29-0.76; P = 0.002; I ² = 0%).

WATCHMAN and Amulet demonstrate no significant difference in efficacy and safety for most LAAC outcomes, including stroke and major bleeding. However, WATCHMAN is associated with a significantly lower risk of pericardial effusion but a higher risk of device thrombosis.