Predictors of myocardial damage prior to hospital admission among patients with acute chest pain or other symptoms raising a suspicion of acute coronary syndrome.
OBJECTIVE
To evaluate factors which, prior to hospital admission, predict the development of acute coronary syndrome or acute myocardial infarction among patients who call for an ambulance due to suspected acute coronary syndrome.


METHODS
Prospective observational study.


METHODS
All the patients who called for an ambulance due to suspected acute coronary syndrome in South Hospital's catchment area in Stockholm and in the Municipality of Göteborg between January and November 2000, were included. On arrival of the ambulance crew, a blood sample was drawn for bedside analysis of serum myoglobin, creatine kinase (CK)MB and troponin-I. A 12-lead electrocardiogram (ECG) was simultaneously recorded.


RESULTS
In all, 538 patients took part in the survey. Their mean age was 69 years and 58% were men. In all, 307 patients (57.3%) had acute coronary syndrome and 158 (29.5%) had acute myocardial infarction. Independent predictors of the development of acute coronary syndrome were a history of myocardial infarction (P=0.006), angina pectoris (P=0.005) or hypertension (P=0.017), ECG changes with ST elevation (P<0.0001), ST depression (P<0.0001) or T-wave inversion (P=0.012) and the elevation of CKMB (P=0.005). Predictors of acute myocardial infarction were being a man (P=0.011), ECG changes with ST elevation (P<0.0001) or ST depression (P<0.0001), the elevation of CKMB (P<0.0001) and a short interval between the onset of symptoms and blood sampling (P=0.010).


CONCLUSIONS
Among patients transported by ambulance due to suspected acute coronary syndrome, predictors of myocardial damage can be defined prior to hospital admission on the basis of previous history, sex, ECG changes, the elevation of biochemical markers and the interval from the onset of symptoms until the ambulance reaches the patient.
Svensson
Leif
L
Division of Cardiology, South Hospital, SE-118 83 Stockholm, Sweden. leif.svensson@sos.sll.se.
Isaksson
Leif
L
Axelsson
Christer
C
Nordlander
Rolf
R
Herlitz
Johan
J
D000368:Aged; D000369:Aged, 80 and over; D000552:Ambulances; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000097:blood / Q000453:epidemiology / Q000628:therapy*; D003327:Coronary Disease / Q000097:blood / Q000453:epidemiology / Q000628:therapy*; D003402:Creatine Kinase / Q000097:blood; D052279:Creatine Kinase, MB Form; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000097:blood / Q000453:epidemiology / Q000628:therapy*; D010343:Patient Admission; D011237:Predictive Value of Tests; D015995:Prevalence; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D013577:Syndrome; D016896:Treatment Outcome; D019210:Troponin I / Q000097:blood; D020107:Troponin T / Q000097:blood
D015415:Biomarkers; D007527:Isoenzymes; D019210:Troponin I; D020107:Troponin T; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form