PRAGUE-17
(2020)Objective
To compare left atrial appendage closure (LAAC) with direct oral anticoagulants (DOACs) in high-risk atrial fibrillation patients for preventing stroke, bleeding, and cardiovascular events.
Study Summary
• No significant differences in stroke/TIA rates (2.60% vs 2.57% annually) or major bleeding (5.50% vs 7.42% annually)
• LAAC had a 4.5% procedural complication rate including 2 procedure/device-related deaths
Intervention
Left atrial appendage closure with Amulet or Watchman devices versus direct oral anticoagulants (primarily apixaban)
Inclusion Criteria
Nonvalvular AF with indication for anticoagulation, plus history of bleeding requiring intervention, cardioembolic event on anticoagulation, or CHA2DS2-VASc ≥3 plus HAS-BLED >2
Study Design
Arms: LAAC (n=201) vs DOAC (n=201)
Patients per Arm: 201 per arm
Outcome
• All stroke/TIA: 2.60% vs 2.57% (sHR 1.00, 95% CI 0.40-2.51)
• Major/NMCR bleeding: 5.50% vs 7.42% (sHR 0.81, 95% CI 0.44-1.52)
Bottom Line
Among high-risk AF patients, LAAC was noninferior to DOACs for preventing the composite of stroke, systemic embolism, cardiovascular death, major bleeding, and procedure-related complications, though procedural safety remains a concern.
Major Points
- First randomized trial comparing LAAC directly with DOACs (primarily apixaban)
- High-risk population: mean CHA2DS2-VASc 4.7, 47.8% with prior bleeding, 35.3% with prior stroke
- LAAC achieved 90% procedural success rate with 4.5% major complications
- No significant differences in individual components: stroke/TIA, cardiovascular death, or bleeding
- Noninferiority maintained across all pre-specified and post-hoc analyses
Study Design
- Study Type
- Multicenter, randomized, open-label, noninferiority trial
- Randomization
- Yes
- Blinding
- Clinical endpoint committee blinded to treatment allocation; participants and investigators not blinded
- Sample Size
- 402
- Follow-up
- Median 19.9 months (695.9 patient-years)
- Centers
- 10
- Countries
- Czech Republic
Primary Outcome
Definition: Composite of stroke, TIA, systemic embolism, cardiovascular death, major or nonmajor clinically relevant bleeding, or procedure/device-related complications
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| 13.42% per year (41 patients) | 10.99% per year (35 patients) | 0.84 (0.53-1.31) | 0.44 (p=0.004 for noninferiority) |
Limitations & Criticisms
- Underpowered to detect differences in individual components like stroke alone
- Short median follow-up (19.9 months) may not capture long-term differences
- Open-label design with potential for bias
- High-risk population limits generalizability to lower-risk AF patients
- Composite endpoint mixing efficacy and safety outcomes may obscure clinically important differences
- Procedural complications including 2 deaths highlight ongoing safety concerns with LAAC
- Four centers were de novo LAAC sites which may have affected complication rates
Citation
J Am Coll Cardiol 2020;75:3122–35