Left ventricular function and heart failure in myocardial infarction: impact of the new definition in the community.
OBJECTIVE
The aim of this study is to evaluate ventricular function and the occurrence of heart failure (HF) among persons with myocardial infarction (MI) meeting only troponin criteria compared to persons meeting creatine kinase and its MB fraction (CK-MB) criteria.


BACKGROUND
The 2000 American College of Cardiology/European Society of Cardiology MI definition enabled identification of MIs meeting only troponin-based criteria. Data on ventricular function and HF among these are lacking.


METHODS
Between November 2002 and May 2006, we prospectively identified 835 persons with MI in the community using standardized criteria including cardiac pain, electrocardiogram, and biomarkers. Troponin and CK-MB were prospectively measured in all; each patient was classified according to the criteria met.


RESULTS
We performed echocardiograms (median of 1 day post-MI) in 482 patients (age 68+/-15 years; 45% women); 363 patients met CK-MB criteria, whereas 119 met only troponin criteria. The latter had lower wall motion score index (1.3+/-0.4 vs 1.5+/-0.5 for CK-MB; P<.01). Diastolic dysfunction was similar in both groups. After 1 year of follow up, 142 patients developed post-MI HF. Patients meeting only troponin criteria had a lower risk of HF after adjustment for age, sex, comorbidity (hazard ratio 0.56, 95% confidence interval 0.37-0.85, P<.01), which persisted after further adjustments for systolic or diastolic function.


CONCLUSIONS
In the community, the prospective application of the new MI definition identifies patients meeting only troponin criteria with better systolic function than cases meeting CK-MB criteria. Such MIs have a lower risk of subsequent HF. These findings are important for risk stratification in clinical practice.
Arruda-Olson
Adelaide M
AM
Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
Pellikka
Patricia A
PA
Bursi
Francesca
F
Jaffe
Allan S
AS
Santrach
Paula J
PJ
Kors
Jan A
JA
Killian
Jill M
JM
Weston
Susan A
SA
Roger
Véronique L
VL
D000368:Aged; D003402:Creatine Kinase / Q000097:blood; D005260:Female; D006333:Heart Failure / Q000209:etiology*; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000097:blood / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology*; D014336:Troponin / Q000097:blood; D016277:Ventricular Function, Left
D014336:Troponin; D003402:Creatine Kinase