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Published on: February 28, 2012
One-Year Safety and Performance of a Dual-Chamber Leadless Pacemaker
Reinoud E Knops1, James E Ip2, Rahul Doshi3
1Amsterdam UMC, the Netherlands (R.E.K., K.T.N.B.).
Background:
A dual-chamber leadless pacemaker can provide bradycardia therapy to most patients with pacemaker indications without the complications associated with a lead or pulse generator. We sought to confirm whether previously reported 3-month safety and performance outcomes were sustained through 12 months by determining whether 12-month complication-free and performance success rates exceeded their prespecified performance goals.
Methods:
Patients were enrolled in the prospective, single-group Aveir DR i2i Study if they had a standard indication for dual-chamber pacing. Enrolled patients were implanted with an Aveir DR dual-chamber leadless pacemaker system, which comprised 2 communicating leadless pacemakers (1 in the right atrium and 1 in the right ventricle). The primary safety outcome evaluated whether freedom from serious device- or procedure-related events through 365 days exceeded the predetermined performance goal of 76.5%. The primary performance outcome determined whether the composite of atrial capture threshold (≤3.0 V at 0.4 ms) and sensing amplitude (P-wave ≥1.0 mV) at the 12-month visit exceeded the predetermined performance goal of 80.0%.
Results:
Sites attempted implantation in 300 subjects, where 63.3% had sinus-node dysfunction and 33.3% had atrioventricular block as their primary pacing indication. The primary safety end point was achieved, with a Kaplan-Meier 12-month complication-free rate of 88.6% (95% CI, 84.5-91.8; P<0.001). The primary performance end point was achieved in 92.8% of patients (95% CI, 89.7-95.8; P<0.001).
Conclusions:
Both primary safety and performance end points were met after 1 year, demonstrating consistency with previously reported 3-month outcomes of a dual-chamber leadless pacemaker.
Registration:
URL: https://www.clinicaltrials.gov; Unique identifier: NCT05252702.
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