title: Effects of an early invasive strategy on ischemia and exercise tolerance among patients with unstable coronary artery disease.
abstract: BACKGROUND
  An early invasive approach after an episode of unstable coronary artery disease has beneficial effects on mortality and myocardial infarction, but its effects on exercise capacity and ischemia have not been investigated.
  
  
  METHODS
  In the Fast Revascularisation during InStability in Coronary disease (FRISC) II trial, 2457 patients with unstable coronary artery disease were assigned randomly to an early invasive or noninvasive strategy. A symptom-limited bicycle exercise test was performed before discharge in the noninvasive group and after 3 months in both groups.
  
  
  RESULTS
  At 3 months, 86% (1046/1222) of the patients in the invasive group and 81% (995/1235) in the noninvasive group performed the exercise test. Before the test, revascularization had been performed in 78% (n = 819) of these patients in the invasive group compared with 28% (n = 281) of those in the noninvasive group. The mean (+/- SD) exercise capacity was higher (6.4 +/- 1.9 vs. 6.2 +/- 1.9 metabolic equivalents [METS], P <0.01), and the occurrence of ischemia lower (23% [229/1004] vs. 36% [352/966], P <0.001) in the invasive group. In the noninvasive group, 882 patients performed an exercise test both predischarge and at 3 months. If a revascularization procedure was performed (n = 210), exercise tolerance increased from 5.1 +/- 1.4 to 6.0 +/- 1.8 METS (P <0.001) and the number of patients with ST depression decreased from 65% (131/203) to 31% (63/203) (P <0.001). Without revascularization (n = 670), exercise tolerance increased from 5.9 +/- 2.2 to 6.3 +/- 1.9 METS (P <0.001), and there were no differences in the occurrence of ischemia.
  
  
  CONCLUSIONS
  In unstable coronary artery disease, an invasive strategy improves exercise tolerance and reduces exercise-induced ischemia.
authors.affiliation: Department of Cardiology, University Hospital, Uppsala, Sweden. erik.diderholm@thorax.uas.lul.se
authors.forename: Erik
authors.initials: E
authors.lastname: Diderholm
authors.forename: Bertil
authors.initials: B
authors.lastname: Andrén
authors.forename: Gunnar
authors.initials: G
authors.lastname: Frostfeldt
authors.forename: Margareta
authors.initials: M
authors.lastname: Genberg
authors.forename: Tomas
authors.initials: T
authors.lastname: Jernberg
authors.forename: Bo
authors.initials: B
authors.lastname: Lagerqvist
authors.forename: Bertil
authors.initials: B
authors.lastname: Lindahl
authors.forename: Lars
authors.initials: L
authors.lastname: Wallentin
mesh_terms: D000789:Angina, Unstable / Q000209:etiology / Q000628:therapy; D017023:Coronary Angiography; D017985:Dalteparin / Q000627:therapeutic use; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications / Q000175:diagnosis* / Q000628:therapy*; D009204:Myocardial Revascularization; D011237:Predictive Value of Tests; D011379:Prognosis; D020127:Recovery of Function; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D017985:Dalteparin