(CCSP037) 2-YEAR OUTCOMES OF LEADLESS VS. TRANSVENOUS SINGLE CHAMBER VENTRICULAR PACEMAKER IN HIGH-RISK SUBGROUPS

Background: This study compares clinical outcomes between leadless pacemakers (leadless-VVI) and transvenous ventricular pacemakers (transvenous-VVI) in subgroups of patients at higher risk of pacemaker complications.

METHODS AND RESULTS: This study is based on the Micra Coverage with Evidence Development (CED) Study. Patients from the Micra CED study were considered in a high-risk subgroup if they had a diagnosis of chronic kidney disease Stages 4-5 (CKD45), end-stage renal disease (ESRD), malignancy, diabetes, tricuspid valve disease (TVD), or chronic obstructive pulmonary disease (COPD) 12 months prior to pacemaker implant. A pre-specified set of complications and reinterventions were identified using diagnosis and procedure codes. Competing risks models were used to compare reinterventions and complications between leadless-VVI and transvenous-VVI patients within each subgroup; results were adjusted for multiple comparisons. Post-hoc analyses of a composite outcome of reinterventions and device complications and a comparison of outcomes by the number of high-risk comorbidities were conducted.

Out of 27,991 patients, 9,858 leadless-VVI and 12,157 transvenous-VVI patients have at least one high-risk comorbidity. Compared to transvenous-VVI patients, leadless-VVI patients in four subgroups (Malignancy, HR 0.68, [0.48-0.95]; Diabetes, HR 0.69, [0.53-0.89]; TVD, HR 0.60 [0.44-0.82]; COPD, HR 0.73, [0.55-0.98]) had fewer complications, in three subgroups (Diabetes, HR 0.58, [0.37-0.89]; TVD, HR 0.46 [0.28-0.76]; COPD, HR 0.51, [0.29-0.90]) had fewer reinterventions, and in four subgroups (Malignancy, HR 0.52, [0.32-0.83]; Diabetes, HR 0.52, [0.35-0.77]; TVD, HR 0.44 [0.28-0.70]; COPD, HR 0.55, [0.34-0.89]) had lower rates of the combined outcome. Leadless-VVI patients that have 0, 1, and 2 high-risk comorbidities have between 30% and 45% fewer chronic complications than transvenous-VVI patients (0 comorbidities, HR 0.55, [0.39 – 0.78]; 1 comorbidity, HR 0.57, CI [0.43 – 0.76]; 2 comorbidities, HR 0.70, CI [0.51 – 0.95]). At all levels of the number of comorbidities, leadless-VVI patients have fewer reinterventions than transvenous-VVI patients (0 comorbidities, HR 0.47, CI [0.29 – 0.75]; 1 comorbidity, HR 0.61, CI [0.40 – 0.94]; 2 comorbidities, HR 0.53, CI [0.30 – 0.93]; >2 comorbidities, HR 0.54, CI [0.31 – 0.95]).

Conclusion: In a real-world study, leadless pacemaker patients had lower 2-year complications and reinterventions rates compared with transvenous-VVI pacing in several high-risk subgroups.