title: Baroreflex sensitivity predicts long-term cardiovascular mortality after myocardial infarction even in patients with preserved left ventricular function.
abstract: OBJECTIVE
  This study sought to assess the long-term predictive power of depressed baroreflex sensitivity (BRS) among post-myocardial infarction (MI) patients with preserved left ventricular function.
  
  
  BACKGROUND
  Risk stratification after MI is primarily performed by identifying patients with depressed left ventricular ejection fraction (LVEF) because of their greater mortality. Autonomic markers can help refining risk stratification. Depressed BRS (<3 ms/mm Hg) correlated with cardiovascular mortality in 1,284 post-MI patients during a 21-month follow-up in the multicenter ATRAMI (Autonomic Tone and Reflexes After Myocardial Infarction) study, but had no significant predictive power in patients with LVEF >35% or above age 65 years.
  
  
  METHODS
  Two hundred forty-four consecutive post-MI patients (age 59 +/- 10 years) with LVEF >35% (average 54 +/- 8%) were enrolled. They underwent a complete assessment, including BRS 4 weeks after MI.
  
  
  RESULTS
  During a 5-year mean follow-up, 14 (5.7%) patients died of cardiovascular causes. Multivariate analysis identified BRS (p = 0.0001), but not LVEF and age, as predictive of cardiovascular mortality. The relative risk (95% confidence interval [CI]) for depressed BRS was 11.4 (95% CI 3.3 to 39.0) for the overall population, 19.6 (95% CI 4.1 to 94.8) for patients </=65 years, and 7.2 (95% CI 1.3 to 39.9) for patients above age 65.
  
  
  CONCLUSIONS
  Even among the large number of low-risk post-MI patients with preserved left ventricular function, depressed BRS identifies, independently of age, a subgroup at long-term high risk for cardiovascular mortality in which more aggressive preventive strategies should be considered.
authors: Department of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors: Gaetano M
authors: GM
authors: De Ferrari
authors: Antonio
authors: A
authors: Sanzo
authors: Alessandra
authors: A
authors: Bertoletti
authors: Giuseppe
authors: G
authors: Specchia
authors: Emilio
authors: E
authors: Vanoli
authors: Peter J
authors: PJ
authors: Schwartz
mesh_terms: D000367:Age Factors; D000368:Aged; D017704:Baroreflex / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000401:mortality* / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology* / Q000628:therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods; D013318:Stroke Volume / Q000502:physiology; D015996:Survival Rate