title: The association between institutional primary angioplasty procedure volume and outcome in elderly Americans.
abstract: BACKGROUND
  The association between greater procedure volume and improved patient outcome in cardiac procedures has been established in percutaneous transluminal coronary angioplasty (PTCA), coronary stent placement and coronary bypass surgery. The association between primary angioplasty volume and outcome has not been evaluated.
  
  
  METHODS
  We evaluated the association between the volume of primary angioplasty procedures with short- and long-term outcome in 6,124 patients with documented acute myocardial infarction. Patients without shock on presentation treated with primary coronary angioplasty within 12 hours of hospital admission were selected from consecutive infarct patients included in the Cooperative Cardiovascular Project database. Patients were divided into quartiles based on the volume of primary PTCA procedures performed at their admitting hospital.
  
  
  RESULTS
  The majority of United States (US) hospitals performed less than three primary PTCA procedures per month. Patients admitted to hospitals in the lowest volume quartile of primary PTCA had 31% higher 30-day mortality than those admitted to the highest volume quartile. After adjustment for baseline differences in patient characteristics, there was an association between admission to higher volume primary PTCA hospitals and lower 30-day mortality (odds ratio per volume quartile = 0.91; 95% confidence interval = 0.83-0.99).
  
  
  CONCLUSIONS
  Eighty-two percent of US hospitals perform less than three primary PTCA procedures per month. In elderly Americans treated with primary PTCA, we observed an association between admission to higher volume hospitals and lower short- and long-term mortality. This association was independent of total PTCA volumes.
authors.affiliation: VA Puget Sound Healthcare System, 1660 South Columbian Way, HSR&D (152), Seattle, WA, 98108, USA. nevery@u.washington.edu
authors.forename: N R
authors.initials: NR
authors.lastname: Every
authors.forename: C
authors.initials: C
authors.lastname: Maynard
authors.forename: K
authors.initials: K
authors.lastname: Schulman
authors.forename: J L
authors.initials: JL
authors.lastname: Ritchie
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000401:mortality* / Q000706:statistics & numerical data*; D002983:Clinical Competence; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D006278:Medicare; D009203:Myocardial Infarction / Q000401:mortality* / Q000628:therapy; D016017:Odds Ratio; D017410:Practice Guidelines as Topic; D013503:Surgery Department, Hospital / Q000592:standards / Q000706:statistics & numerical data; D013996:Time and Motion Studies; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D014600:Utilization Review