Coronary late lumen loss of drug eluting stents is associated with increased serum levels of the complement components C3a and C5a.
OBJECTIVE
Drug eluting stents (DES) reduce recurrent luminal narrowing through anti-migratory and anti-proliferative effects. However, recent concerns arose that DES may also induce significant chronic inflammatory responses that may impair vascular healing and lead to in-stent restenosis (ISR). As the complement components C3a and C5a exert particularly strong chemotactic and proinflammatory effects, we examined the association of serum levels of C3a and C5a and ISR after implantation of DES.


METHODS
We included 82 patients that were treated with 151 DES. Blood samples were taken directly before and 24h after PCI. Serum levels of C3a and C5a were measured by specific ELISA and restenosis was evaluated at 6-8 months by coronary angiography.


RESULTS
C5a but not C3a increased after implantation of DES (p<0.05). During the follow-up period, two patients (2.4%) died of cardiovascular causes and 12 patients (7.9% of stents, 15% of patients) developed ISR. Serum levels of C3a before and 24h after PCI as well as C5a levels at baseline were significantly higher in patients that developed ISR at follow-up. C3a and C5a at baseline were significantly associated to angiographic late lumen loss independent from clinical and procedural risk factors.


CONCLUSIONS
Increased complement activation as measured by higher levels of C3a and C5a before PCI is significantly associated with late lumen loss. Inhibition of the complement cascade to prevent ISR warrants further investigation.
Speidl
Walter S
WS
Department of Internal Medicine II, Medical University of Vienna, Waehringerguertel 18-20, Vienna, Austria. walter.speidl@meduniwien.ac.at
Katsaros
Katharina M
KM
Kastl
Stefan P
SP
Zorn
Gerlinde
G
Huber
Kurt
K
Maurer
Gerald
G
Wojta
Johann
J
Christ
Günter
G
D000368:Aged; D015926:Complement C3a / Q000032:analysis*; D015936:Complement C5a / Q000032:analysis*; D023903:Coronary Restenosis / Q000097:blood* / Q000209:etiology*; D054855:Drug-Eluting Stents / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
D015926:Complement C3a; D015936:Complement C5a