title: [The effect of specialised medical procedures on the hosptial standardised mortality ratio in cardiac centers].
abstract: OBJECTIVE
  To examine the impact of specialised medical procedures (SMPs) on the hospital standardized mortality ratio (HSMR) in Dutch cardiac centres.
  
  
  METHODS
  Retrospective, calculation of the HSMR.
  
  
  METHODS
  Data from 2004 from the National Medical Registration (LMR) were used to calculate the HSMR in 12 cardiac centres and all other hospitals in the Netherlands. The HSMRwas then recalculated for the 12 cardiac centres excluding either percutaneous transluminal coronary angioplasty (PTCA) or open heart surgery or both to determine the impact of these SMPs on the HSMR.
  
  
  RESULTS
  Exclusion of SMPs from the HSMR calculation changed the HSMR for individual cardiac centres, ranging from a 4.7% decrease to a 5.3% increase. Change in HSMR was related to the relative frequency of the two procedures at each cardiac centre. Mortality risk was lower than average for PTCA and higher than average for open heart surgery. PTCA accounted for 5.6%-20.2% of total admissions in the 12 cardiac centres. A relatively high proportion of PTCA procedures was associated with a lower HSMR, to a maximum decrease of nearly 7% in one cardiac centre. Open heart surgery accounted for 2.1%-12.6% of total admissions per cardiac centre. A relatively high proportion ofopen heart procedures was associated with an increased HSMR, to a maximum increase of nearly 8% in one cardiac centre.
  
  
  CONCLUSIONS
  Specialised medical procedures for heart conditions influence the HSMR of cardiac centres. The increase or decrease in HSMR is related to the relative frequency of PTCA and open heart surgery. These results can be used to help interpret the differences in HSMR among cardiac centres and other hospitals.
authors.affiliation: St. Antonius Ziekenhuis, Koekoekslaan 1, 3435 CM Nieuwegein. w.bosch@antonius.net
authors.forename: W F
authors.initials: WF
authors.lastname: van den Bosch
authors.forename: W C
authors.initials: WC
authors.lastname: Graafmans
authors.forename: D
authors.initials: D
authors.lastname: Pieter
authors.forename: G P
authors.initials: GP
authors.lastname: Westert
mesh_terms: D015906:Angioplasty, Balloon, Coronary / Q000401:mortality*; D006348:Cardiac Surgical Procedures / Q000401:mortality*; D019538:Health Care Surveys; D017052:Hospital Mortality; D006801:Humans; D009426:Netherlands; D010351:Patient Discharge / Q000706:statistics & numerical data*; D019984:Quality Indicators, Health Care; D012189:Retrospective Studies