The ability of an electrocardiogram to predict fatal and non-fatal cardiac events in asymptomatic middle-aged subjects.
The long-term prognostic value of a standard 12-lead electrocardiogram (ECG) for predicting cardiac events in apparently healthy middle-aged subjects is not well defined.



A total of 9511 middle-aged subjects (mean age 43 ± 8.2 years, 52% males) without a known cardiac disease and with a follow-up 40 years were included in the study. Fatal and non-fatal cardiac events were collected from the national registries. The predictive value of ECG was separately analyzed for 10 and 30 years. Major ECG abnormalities were classified according to the Minnesota code.



Subjects with major ECG abnormalities (N = 1131) had an increased risk of cardiac death after 10-years (adjusted hazard ratio [HR] 1.7; 95% confidence interval [95% CI], 1.1-2.5, p = 0.009) and 30-years of follow-up (HR 1.3, 95% CI, 1.1-1.5, p < 0.001). Model discrimination measured with the C-index showed only a minor improvement with the inclusion of ECG abnormalities: 0.851 versus 0.853 and 0.742 versus 0.743 for 10- and 30-year follow-up, respectively. ECG did not predict non-fatal cardiac events after 10-years or 30-years of follow-up.



Major ECG abnormalities are associated with an increased risk of short and long-term cardiac mortality in middle-aged subjects. However, the improvement in discrimination between subjects with and without fatal cardiac events was marginal with abnormal ECG.



Abnormalities observed on 12-lead electrocardiogram are shown to have prognostic significance for cardiac events in elderly subjects without known cardiac disease. Our results suggest that ECG abnormalities increase the risk of fatal cardiac events also in middle-aged healthy subjects.
a Medical Research Center , Oulu University Hospital, University of Oulu , Oulu , Finland.
Henri K
HK
Terho
a Medical Research Center , Oulu University Hospital, University of Oulu , Oulu , Finland.
Jani T
JT
Tikkanen
a Medical Research Center , Oulu University Hospital, University of Oulu , Oulu , Finland.
Tuomas V
TV
Kenttä
a Medical Research Center , Oulu University Hospital, University of Oulu , Oulu , Finland.
M Juhani
MJ
Junttila
b Heart and Lung Center , Helsinki University Hospital , Helsinki , Finland.
Aapo L
AL
Aro
c Päijät-Häme Central Hospital , Lahti , Finland.
Olli
O
Anttonen
c Päijät-Häme Central Hospital , Lahti , Finland.
Tuomas
T
Kerola
d National Institute of Health and Welfare , Helsinki , Finland.
Harri A
HA
Rissanen
d National Institute of Health and Welfare , Helsinki , Finland.
Paul
P
Knekt
d National Institute of Health and Welfare , Helsinki , Finland.
Antti
A
Reunanen
a Medical Research Center , Oulu University Hospital, University of Oulu , Oulu , Finland.
Heikki V
HV
Huikuri
D000328:Adult; D002318:Cardiovascular Diseases / Q000401:mortality* / Q000503:physiopathology; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005387:Finland; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012042:Registries; D012307:Risk Factors
Cardiac events; death; electrocardiography; follow-up studies; risk prediction