Impact of prior aspirin therapy on clinical manifestations of cardiovascular implantable electronic device infections

Cardiovascular implantable electronic device (CIED) infection may present as pocket infection or as infective endocarditis (CIED-IE) with vegetation on device leads or heart valves. As aspirin has both anti-inflammatory properties and interferes with platelet aggregation, we hypothesized that ongoing anti-platelet therapy with aspirin may impact clinical and echocardiographic manifestations of CIED infection. We retrospectively reviewed 415 cases of CIED infection admitted to Mayo Clinic Rochester from 1991 to 2008. Information regarding aspirin use was available in 392 (94.5) cases and 178 (45) had received aspirin therapy prior to clinical onset of CIED infection. Although there were no significant differences in pathogen distribution between patients who had received prior aspirin therapy as compared with those who did not, patients on aspirin therapy were less likely to report chills (25 vs. 35, P 0.04), sweats (9 vs.18, P 0.01), or have peripheral leukocytosis on admission (33 vs. 46, P 0.005). Overall, 82 (21) of 392 patients met the clinical criteria for CIED-IE. Patients on prior aspirin therapy were significantly less likely to have vegetations on CIED leads or heart valves than those who had not received it (15 vs. 26, P 0.01). However, despite the lower frequency of CIED-IE in the aspirin group, there was no significant difference (P 0.97) in the overall survival between the two groups. Aspirin therapy prior to onset of CIED infection was associated with a lower likelihood of vegetation formation on CIED leads or heart valves and associated systemic manifestations of infection.