title: Usefulness of abnormal heart rate turbulence to predict cardiovascular mortality in high-risk patients with acute myocardial infarction and left ventricular dysfunction (from the EPHESUS study).
abstract: Heart rate turbulence (HRT) is a promising marker for risk of mortality after acute myocardial infarction (AMI). We investigated HRT for risk stratification in high-risk patients after MI. HRT from 24-hour Holter monitoring in 481 hospitalized patients after AMI with heart failure and/or diabetes with left ventricular dysfunction before randomization in the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study (EPHESUS). Over a 1-year follow-up, 55 died, 49 of cardiovascular causes. HRT onset (TO) and slope (TS) were calculated using previous and cohort-optimized cutpoints and their independent contribution to risk of cardiovascular death determined. Models were tested with <5 ventricular premature complexes (PVCs) categorized as normal (n = 452) and with <5 VPCs excluded (n = 342). In EPHESUS, optimal cutpoints were TS < or = 3.0 and TO > or = 0.0. The strongest model for predicting cardiovascular mortality used EPHESUS cutpoints excluding subjects with <5 VPCs. On 3-category HRT model multivariate analysis (TS and TO normal, TS or TO abnormal, TS and TO abnormal), both TS and TO abnormal (relative risk 3.64, 95% confidence interval 1.55 to 8.55, p = 0.003) and left ventricular ejection fraction < or =30% (relative risk 1.97, 95% confidence interval 1.04 to 3.73, p = 0.037) independently predicted cardiovascular death. In conclusion, HRT is an independent predictor of cardiovascular death in a high-risk population after AMI, with a possibly higher optimal cutpoint for HRT slope than previously reported.
authors.affiliation: Washington University School of Medicine, St. Louis, Missouri, USA. pstein@im.wustl.edu
authors.forename: Phyllis K
authors.initials: PK
authors.lastname: Stein
authors.forename: Prakash
authors.initials: P
authors.lastname: Deedwania
mesh_terms: D000368:Aged; D015716:Electrocardiography, Ambulatory; D000077545:Eplerenone; D005260:Female; D006333:Heart Failure / Q000188:drug therapy; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D000451:Mineralocorticoid Receptor Antagonists / Q000627:therapeutic use; D009203:Myocardial Infarction / Q000503:physiopathology; D018570:Risk Assessment; D013148:Spironolactone / Q000031:analogs & derivatives / Q000627:therapeutic use; D018487:Ventricular Dysfunction, Left / Q000401:mortality* / Q000503:physiopathology*
chemical_list: D000451:Mineralocorticoid Receptor Antagonists; D013148:Spironolactone; D000077545:Eplerenone