Article

Baroreflex sensitivity predicts long-term cardiovascular mortality after myocardial infarction even in patients with preserved left ventricular function.

Department of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
Journal of the American College of Cardiology (impact factor: 14.16). 01/2008; 50(24):2285-90. DOI:10.1016/j.jacc.2007.08.043 pp.2285-90
Source: PubMed

ABSTRACT 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.
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.
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.
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.
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.

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Keywords

1,284 post-MI patients
 
age 65 years
 
aggressive preventive strategies
 
Autonomic markers
 
Autonomic Tone
 
BRS 4 weeks
 
complete assessment
 
depressed baroreflex sensitivity
 
depressed BRS
 
long-term predictive power
 
low-risk post-MI patients
 
multicenter ATRAMI
 
Myocardial Infarction
 
post-myocardial infarction
 
refining risk stratification
 
relative risk
 
Risk stratification
 
significant predictive power
 
ventricular ejection fraction
 
ventricular function