SALUTE
(2018)Objective
To evaluate the safety and efficacy of the WATCHMAN left atrial appendage closure device for Japanese patients with nonvalvular atrial fibrillation at increased risk of thromboembolism
Study Summary
• No periprocedural safety events occurred (0% vs 10% performance target)
• 100% effective LAA closure rate achieved at 6 months with only one ischemic stroke (2.4%)
Intervention
Percutaneous WATCHMAN left atrial appendage closure device implantation
Inclusion Criteria
>20 years old, Japanese, documented NVAF, CHA2DS2-VASc score ≥2, suitable for anticoagulant therapy with appropriate rationale for nonpharmacologic alternative
Study Design
Arms: Single-arm study with 42 patients in primary cohort (ITT) and 12 patients in roll-in cohort
Patients per Arm: 42 (ITT cohort)
Outcome
• Primary efficacy endpoint met: 100% effective LAA closure at 6 months
• One ischemic stroke occurred during 6-month follow-up (2.4%)
Bottom Line
The WATCHMAN LAA closure device demonstrated excellent safety and efficacy in Japanese patients with NVAF, achieving 100% successful implantation, no periprocedural complications, and 100% effective LAA closure at 6 months with only one non-disabling ischemic stroke.
Major Points
- First trial to evaluate LAA closure device safety and efficacy in Japanese population
- 100% successful device implantation rate with experienced proctors
- Met all three co-primary endpoints with performance targets exceeded
- 100% warfarin discontinuation rate achieved during trial
- Results comparable to large-scale randomized trials (PROTECT AF, PREVAIL)
- Single-arm prospective multicenter design limits comparative conclusions
Study Design
- Study Type
- Prospective, multicenter, single-arm clinical trial
- Randomization
- No
- Blinding
- Not applicable (single-arm study)
- Sample Size
- 54
- Follow-up
- 6 months (with planned extension to 24 months)
- Centers
- 10
- Countries
- Japan
Primary Outcome
Definition: 1st co-primary: Periprocedural safety composite (all-cause death, ischemic stroke, systemic embolism, device/procedure-related events requiring surgery within 7 days); 2nd co-primary: Composite of stroke, systemic embolism, CV death at 6 months; 3rd co-primary: Effective LAA closure rate at 45 days and 6 months
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| N/A | 1st: 0% (0/42); 2nd: 2.4% (1/42); 3rd: 100% (42/42) at both timepoints | - (1st: [0.0%, 8.4%]; 2nd: [0.1%, 12.6%]; 3rd: N/A) |
Limitations & Criticisms
- Single-arm design without control group limits comparative conclusions
- Small sample size (42 patients in primary cohort)
- Short follow-up period (6 months) insufficient for long-term efficacy assessment
- All procedures performed with experienced proctors may not reflect real-world outcomes
- Results may not be generalizable to truly new implanters in Japanese practice
- Limited power for subgroup and multivariable analyses due to low event rates
Citation
Circ J 2018; 82: 2946–2953