Cumulative risk assessment in unstable angina: clinical, electrocardiographic, autonomic, and biochemical markers.
OBJECTIVE
To determine the incremental value of clinical data, troponin T, ST segment monitoring, and heart rate variability for predicting outcome in patients with non-ST elevation acute coronary syndromes.


METHODS
Prospective cohort study of 304 consecutive patients. Baseline clinical and electrocardiographic data were recorded, serial blood samples were obtained for troponin T assay, and 48 hour Holter monitoring was performed for ST segment and heart rate variability analysis. End points were cardiac death and non-fatal myocardial infarction during 12 months' follow up.


RESULTS
After 12 months, 7 patients had died and 21 had had non-fatal myocardial infarction. The risk of an event was increased by troponin T > 0.1 microg/l, T wave inversion on the presenting ECG, Holter ST shift, and a decrease in the standard deviation of 5 minute mean RR intervals. Positive predictive values of individual multivariate risk were low; however, analysis of all multivariate risk markers permitted calculation of a cumulative risk score, which increased the positive predictive value to 46.9% while retaining a negative predictive value of 96.9%.


CONCLUSIONS
A cumulative approach to risk stratification in non-ST elevation coronary syndromes successfully identifies a group in whom the risk of cardiac death or non-fatal myocardial infarction approaches 50%.
Kennon
S
S
Department of Cardiology, Barts and the London NHS Trust, London, UK. srok@dircon.co.uk
Price
C P
CP
Mills
P G
PG
MacCallum
P K
PK
Cooper
J
J
Hooper
J
J
Clarke
H
H
Timmis
A D
AD
D000789:Angina, Unstable / Q000097:blood / Q000209:etiology* / Q000503:physiopathology; D001145:Arrhythmias, Cardiac / Q000097:blood / Q000150:complications / Q000503:physiopathology; D003402:Creatine Kinase / Q000097:blood; D052279:Creatine Kinase, MB Form; D016757:Death, Sudden, Cardiac / Q000209:etiology; D015716:Electrocardiography, Ambulatory; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000209:etiology* / Q000503:physiopathology; D018570:Risk Assessment; D020107:Troponin T / Q000097:blood
D007527:Isoenzymes; D020107:Troponin T; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form