title: Can exercise capacity assessed by the 6 minute walk test predict the development of major adverse cardiac events in patients with STEMI after fibrinolysis?
abstract: BACKGROUND
  To assess the added value of the 6 minute walk test distance (6MWTD) in the risk-stratification methods for patients with ST -segment elevation myocardial infarction (STEMI) treated with fibrinolysis.
  
  
  RESULTS
  This is a prospective cohort study of one hundred consecutive patients with STEMI, who had received fibrinolysis, at Assuit University Hospital. All patients underwent 6MWT pre- discharge and were followed up for 3 months to monitor the incidence of major adverse cardiac events (MACE). Patients were divided into 3 groups according to the level of 6MWTD (level I>450 m, level II = 300-450 m and level III<300 m). Among the study population, the median 6MWT distance was 370 meters (interquartile range 162-462). The mean age was 60.9±10.7 years, 71.9% of them were males, 2/3 had anterior MI. only 10.5% had successful thrombolysis. Compared to patients in level I (>450 m), patients in level III (<300 m) were more likely to have clinical risk factors as hypertension, diabetes and impaired renal function. The patient's mean TIMI score was 3.4±2.2, the mean GRACE score was 150.5±27.7. There was a significant negative correlation between the 6 MWTD and GRACE risk score (r = -0.80, p<0.001). At 3 months of follow-up, 51% had MACE including 16% were dead. Multivariate logistic regression analysis identified that the GRACE risk score and 6MWT distance levels were the best predictors of the MACE at 3 month of follow up. The incidence of MACE was 4 times higher in patients with high GRACE risk score who couldn't walk more than 300 meters (OR = 4.66, 95% CI = 1.1-14.5, p = 0.006).
  
  
  CONCLUSIONS
  In patients with STEMI treated with fibrinolysis, the addition of 6MWTD assessment pre-discharge to the traditional GRACE risk score improved the risk prediction of cardiovascular events at 3 month follow up.
authors.affiliation: Department of Cardiovascular Medicine, Faculty of Medicine, Assiut University, Assiut, Egypt.
authors.forename: Ayman K M
authors.initials: AK
authors.lastname: Hassan
authors.affiliation: Department of Cardiovascular Medicine, Faculty of Medicine, Assiut University, Assiut, Egypt.
authors.forename: Salwa R
authors.initials: SR
authors.lastname: Dimitry
authors.affiliation: Department of Cardiovascular Medicine, Faculty of Medicine, Assiut University, Assiut, Egypt.
authors.forename: George W
authors.initials: GW
authors.lastname: Agban
mesh_terms: D000368:Aged; D015444:Exercise; D005080:Exercise Test; D005260:Female; D005342:Fibrinolysis; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D015912:Thrombolytic Therapy; D016138:Walking