Prognostic information from on-line vectorcardiography in acute myocardial infarction.
The present study assesses the prognostic information from continuous on-line vectorcardiography in patients with acute myocardial infarction (AMI). A series of 203 patients with AMI were studied. Vectorcardiographic (VCG) recordings were obtained continuously for 24 hours. Analysis was performed on-line with the commercial system MIDA CoroNet. QRS vector difference (QRS-VD), ST change vector magnitude (STC-VM), and ST vector magnitude (ST-VM) were monitored. Patients were followed for 538 +/- 220 days. During follow-up, 36 patients died from cardiac causes and 38 patients had reinfarction. A significantly higher occurrence of transient VCG changes (QRS-VD, STC-VM, and ST-VM; p < 0.001) was seen in patients who died from cardiac causes or experienced either cardiac death or reinfarction at follow-up. The end value for QRS-VD was higher in patients who died from cardiac causes and correlated with the maximal value for creatine kinase when all patients were considered (r = 0.66; p < 0.001). Significantly lower mortality was seen in patients with VCG trend curves suggestive of coronary reperfusion (p < 0.01). In multivariate analysis, occurrence of transient changes in STC-VM, high QRS-VD end value, and VCG trend curves not suggestive of reperfusion gave additional prognostic information beyond that of age, gender, maximal creatine kinase value, heart size on chest x-ray, occurrence of ventricular fibrillation during hospitalization, and the inability to perform exercise tests. VCG monitoring during the first 24 hours of hospitalization for an AMI is a promising method for early detection of patients with increased risk for subsequent cardiac death or reinfarction.
Department of Medicine, Danderyd Hospital, Stockholm, Sweden.
P
P
Lundin
S V
SV
Eriksson
L E
LE
Strandberg
N
N
Rehnqvist
D000368:Aged; D000369:Aged, 80 and over; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000401:mortality / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012815:Signal Processing, Computer-Assisted; D014672:Vectorcardiography / Q000379:methods