title: Does low individual operator coronary interventional procedural volume correlate with worse institutional procedural outcome?
abstract: OBJECTIVE
  To assess the relation between individual operator coronary interventional volume and incidence of complications, the in-hospital outcome at a single, moderate volume urban academic center was prospectively collected over a 3-year period.
  
  
  BACKGROUND
  A minimum of 75 coronary interventions/operator per year may be required in the future to obtain formal certification. However, few data exist regarding individual operator volumes and procedural outcome.
  
  
  METHODS
  Between January 1993 and December 1995, 1,389 consecutive procedures were performed or supervised by nine geographic full-time operators: 171 (12.3%) utilized various devices, and 350 (25.2%) involved multivessel coronary intervention. Left ventricular ejection fraction was 59 +/- 15% (mean +/- SD), and there were 1.7 +/- 0.7 vessels diseased (with > or = 70% stenosis). Clinical indications included stable angina in 22.5% of cases, unstable angina in 31.9%, acute myocardial infarction (MI) in 2.9%, post MI in 20.6%, shock or acute heart failure in 3.0% and restenosis in 19.1%. In the last consecutive 857 lesions in 655 cases, 20.7% type A, 55.5% type B and 23.8% type C lesions were categorized before coronary intervention.
  
  
  RESULTS
  Average yearly operator volume ranged from 26 to 83 cases (mean 51 +/- 26). Each operator has performed a total of 590 +/- 268 coronary interventions, with 10.0 +/- 4.3 years of coronary interventional experience. The mean angioplasty volume rating for the nine operators was 180 +/- 37 (> 170 considered adequate). The in-hospital major complication rate was 1.4% (95% confidence interval 0.7% to 1.893%) for all coronary interventions, including death in 3 patients, bypass surgery in 13, arrhythmia in 3 and Q wave MI in 2. To ascertain how these outcomes compared with standard measures of coronary interventional outcome, four previously published registries were reanalyzed in a similar manner. The rate of complications in the present study was found to be significantly lower than that of the 1992-1993 Society for Cardiac Angiography and Intervention registry (1.9%, n = 19,594, p < 0.05 [excludes ventricular arrhythmias]), the 1994 American College of Cardiology database (3.9%, n = 38,963, p = 0.001), the Mid-America Heart Institute outcome in 1988 (2.3%, n = 5,413, p = 0.02) and the 1985-1986 National Heart, Lung, and Blood Institute Registry (7.2%, n = 1,801, p = 0.001). Odds ratios and 95% confidence intervals showed the outcome in the current study to be at least comparable to the standard registries.
  
  
  CONCLUSIONS
  Despite individual operator volumes below those currently being considered for credentialing, the overall institutional outcome was excellent in a diverse and complex patient population.
authors.affiliation: Rush Heart Institute, Chicago, IL, USA. lklein@rps/mc.edu
authors.forename: L W
authors.initials: LW
authors.lastname: Klein
authors.forename: G L
authors.initials: GL
authors.lastname: Schaer
authors.forename: J E
authors.initials: JE
authors.lastname: Calvin
authors.forename: B
authors.initials: B
authors.lastname: Palvas
authors.forename: J
authors.initials: J
authors.lastname: Allen
authors.forename: J
authors.initials: J
authors.lastname: Loew
authors.forename: E
authors.initials: E
authors.lastname: Uretz
authors.forename: J E
authors.initials: JE
authors.lastname: Parrillo
mesh_terms: D000046:Academic Medical Centers / Q000592:standards / Q000706:statistics & numerical data; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects* / Q000401:mortality / Q000592:standards / Q000706:statistics & numerical data*; D016507:Cardiology Service, Hospital / Q000592:standards* / Q000706:statistics & numerical data; D002641:Chicago; D002983:Clinical Competence / Q000706:statistics & numerical data*; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data; D003406:Credentialing; D006302:Health Services Research; D017052:Hospital Mortality; D006786:Hospitals, Urban; D006801:Humans; D015994:Incidence; D016017:Odds Ratio; D017063:Outcome Assessment, Health Care; D010818:Practice Patterns, Physicians' / Q000592:standards*; D011446:Prospective Studies; D012042:Registries