Methods
The overall Micra CED Study design has been described previously.2,3,6 The purpose of the study is to evaluate complications, utilization, and outcomes of the leadless VVI pacing system in the US Medicare population. The primary objectives of the Micra CED study were to estimate the acute (30-day) complication rate and the 2-year survival rate associated with the leadless pacing system. The study uses manufacturer device registry information to identify Medicare beneficiaries implanted with a Micra leadless pacemaker (Model MC1VR01, Medtronic, Inc) using a previously-described- linking algorithm.6 The study also identifies a contemporaneous cohort of patients implanted with a transvenous VVI pacemaker from any manufacturer during the study period directly from their Medicare claims. The study was approved by the Western Institutional Review Board with a waiver of informed consent and is registered on ClinicalTrials.gov (NCT03039712).