title: Long-term performance of a simple algorithm for early discharge after ruling out acute coronary syndrome: a prospective multicenter trial.
abstract: OBJECTIVE
  To test the short- and long-term performance of a simple algorithm to detect or rule out acute coronary artery disease (CAD) in patients referred with acute chest pain (CP).
  
  
  METHODS
  Prospective, multicenter study with 30-day and 1-year follow-ups.
  
  
  METHODS
  Emergency and coronary care units of two university hospitals and four affiliated teaching hospitals in a suburban region of northern Switzerland.
  
  
  METHODS
  One hundred sixty-one consecutive patients referred with acute CP with a high CAD risk profile underwent exercise testing (ET) within 24 h if results of two troponin tests and ECG remained normal within 6 h. The patients were discharged if ET results were negative or underwent angiography if the results were positive.
  
  
  RESULTS
  The primary end point was survival free of death, myocardial infarction (MI), and acute coronary syndrome, as well as the correct diagnosis of CAD in need of revascularization. Failure of the algorithm included events not predicted and false-positive ET results. Symptom-limited ET was performed in 142 patients, and stress imaging was performed in 17 patients. Discharge within 24 h was possible in 76%. Angiography in 21 patients showed no CAD in 4 patients, whereas revascularization was necessary in 17 patients. During follow-up, three patients had an MI (one fatal) and two patients had unstable angina, for an event rate of 3.1%/yr. Overall sensitivity of the algorithm to detect CAD was 71%, whereby six of seven false-positive ET results were due to exercise-induced CP without ECG changes. More importantly, the negative predictive value was 96.4%, indicating that this simple algorithm failed to identify only 3.6% of patients at risk for future events.
  
  
  CONCLUSIONS
  Discharge within 24 h after onset of acute CP in high-risk CAD patients is safe, irrespective of CAD history, if ECG findings remain unchanged and troponin test results are normal within 6 h, and if results of adequate ET are negative.
authors.affiliation: University Hospital, Petersgraben 4, CH-4031 Basel, Switzerland.
authors.forename: Beat Andreas
authors.initials: BA
authors.lastname: Schaer
authors.forename: Daniel
authors.initials: D
authors.lastname: Jenni
authors.forename: Peter
authors.initials: P
authors.lastname: Rickenbacher
authors.forename: Christoph
authors.initials: C
authors.lastname: Graedel
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Crevoisier
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Iselin
authors.forename: Matthias
authors.initials: M
authors.lastname: Pfisterer
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000789:Angina, Unstable / Q000175:diagnosis*; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis*; D010351:Patient Discharge; D011446:Prospective Studies; D013577:Syndrome; D013997:Time Factors