Long-term outcomes following infection of cardiac implantable electronic devices: a prospective matched cohort study

Abstract

Objective: To assess long-term outcomes and predictors of mortality in patients treated according to current recommendations for cardiac implantable electronic device (CIED) infection.

Design: Two-group matched cohort study.

Setting: Tertiary-care institution.

Patients: Consecutive patients admitted for CIED infection between 2004 and 2008 were prospectively enrolled. Study subjects were matched to a cohort of uninfected CIED patients by age, sex and type of device.

Interventions: In all infected patients, the therapeutic approach consisted of complete hardware removal whenever possible, antimicrobial therapy, and implantation of a new device, if indicated. Patients were systematically followed, with standardised outcomes assessment.

Main outcome measures: All-cause mortality and predictors of long-term mortality.

Results: 197 patients were included and matched 1:1 to controls. Pocket infections were present in 41.1% and definite or suspected infective endocarditis in 58.9%. Total or subtotal hardware removal was achieved in 98.5% of cases. Median follow up was 25 months (12-70). Mortality rates in the study group and controls were 14.3% vs 11.0% (NS) at 1 year and 35.4% vs 27.0% (p=NS) at 5 years. Independent predictors of long-term mortality were older age (HR=1.09, p<0.001), cardiac resynchronisation therapy (HR=3.70, p=0.001), thrombocytopenia (HR=5.10, p=0.003) and renal insufficiency (HR=2.66, p=0.006). In patients with reimplanted devices, epicardial right ventricular pacemakers were associated with higher mortality (HR=2.85, p=0.034).

Conclusion: In patients with CIED infection managed by recommended therapy, long-term mortality rates are similar to comparable controls. Independent predictors include patient and disease-related factors, in addition to implantation of right ventricular epicardial pacemakers.