title: Outcomes after coronary stent implantation in patients with metal allergy.
abstract: BACKGROUND
  Clinical outcomes after stent placement in patients with a history of metal allergy remain incompletely understood. We performed a single-center retrospective study to evaluate such outcomes.
  
  
  RESULTS
  Twenty-nine allergic patients who underwent coronary stent implantation were compared with a nonallergic group (n=250) matched for demographics and a propensity score for allergy to metal. Hypersensitivity to nickel was reported in 26 of 29 and chromium in 9 of 29. Patch testing performed in 11 of 29 patients was positive in all. Comparing allergy versus control subjects, there were no differences in number of segments treated (1.4±0.7 versus 1.5±0.7), stents placed (1.7±1.1 versus 1.6±0.9), and frequency of drug-eluting stent usage (52% versus 60%). In-hospital death (0% versus 0%), myocardial infarction (MI, 4% versus 3%, P=0.27), and 30-day death (3% versus 0%, P=0.53) and MI (3% versus 4%, P=0.71) were statistically similar. There were no differences in 4-year death (12% versus 13%), target lesion revascularization (TLR, 13 versus 17%, P=0.54), or death/MI/TLR (24% versus 34%, P=0.20). Clinically driven repeat angiography in 12 of 29 allergy patients revealed binary restenosis rates of 27% in bare metal stents and 0% in drug-eluting stents, with mean diameter in-stent restenosis of 36% and 8%, respectively. There was no change in circulating eosinophil and lymphocyte counts after stenting in the allergy group (0.19-0.20, P=0.67, and 1.90-1.79, P=0.59, respectively).
  
  
  CONCLUSIONS
  A history of metal allergy was not associated with adverse early or late outcomes in this single-center study.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Santiago
authors.initials: S
authors.lastname: Romero-Brufau
authors.forename: Patricia J M
authors.initials: PJ
authors.lastname: Best
authors.forename: David R
authors.initials: DR
authors.lastname: Holmes
authors.forename: Verghese
authors.initials: V
authors.lastname: Mathew
authors.forename: Mark D P
authors.initials: MD
authors.lastname: Davis
authors.forename: Gurpreet S
authors.initials: GS
authors.lastname: Sandhu
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Lennon
authors.forename: Charanjit S
authors.initials: CS
authors.lastname: Rihal
authors.forename: Rajiv
authors.initials: R
authors.lastname: Gulati
mesh_terms: D000368:Aged; D000485:Allergens / Q000009:adverse effects; D019917:Blood Vessel Prosthesis Implantation; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000150:complications / Q000453:epidemiology / Q000401:mortality / Q000601:surgery*; D003331:Coronary Vessels / Q000187:drug effects / Q000473:pathology* / Q000601:surgery; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000150:complications* / Q000453:epidemiology / Q000401:mortality; D008297:Male; D008670:Metals / Q000009:adverse effects / Q000276:immunology*; D008875:Middle Aged; D009204:Myocardial Revascularization / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012882:Skin Tests; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000485:Allergens; D008670:Metals