Lipoprotein(a) and apolipoproteins B and A-I after acute myocardial infarction.
OBJECTIVE
To assess the temporal behaviour of plasma lipoprotein(a) [Lp(a)]--a low density lipoprotein-like particle whose plasma levels are associated with atherosclerosis risk--and apolipoproteins (apo) B and A-I (the major protein components of low and high density lipoproteins, respectively) in acute myocardial infarction (AMI), and to determined the effect of tissue plasminogen activator (tPA) on them.


METHODS
Serial Lp(a), apoB and apoA-I determinations were obtained over eight days in 19 AMI patients who were part of a randomized, placebo (n = 7) controlled trial of tPA (n = 12).


RESULTS
At 48 h postinfarct, plasma Lp(a) and apoB concentrations were, respectively, 20% (24.9 +/- 3.0 to 19.9 +/- 2.9 mg/dL, P < 0.05) and 28% (1.37 +/- 0.10 to 0.99 +/- 0.11 mM/L, P < 0.05) below baseline values. ApoA-I concentrations were unchanged at 48 h postinfarct. At 192 h postinfarct, Lp(a) rebounded to 36% above baseline (24.9 +/- 3.0 to 33.9 +/- 3.9 mg/dL, P < 0.05), apoB returned to baseline (1.37 +/- 0.10 versus 1.33 +/- 0.11 g/L, P < 0.05) and apoA-I was 15% below baseline (1.43 +/- 0.06 to 1.21 +/- 0.06 g/L, not significant). Administration of tPA had no effect on any of these changes.


CONCLUSIONS
Plasma Lp(a) and apolipoproteins undergo shifts from baseline values in the postinfarct period and tPA has no effect on these variations.
Husain
M
M
Department of Clinical Biochemistry, St Michael's Hospital, University of Toronto, Ontario.
Armstrong
P W
PW
Connelly
P W
PW
Hegele
R A
RA
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016632:Apolipoprotein A-I / Q000097:blood; D001055:Apolipoproteins B / Q000097:blood; D015986:Confounding Factors, Epidemiologic; D005260:Female; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood; D008074:Lipoproteins / Q000097:blood* / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000188:drug therapy; D010959:Tissue Plasminogen Activator / Q000494:pharmacology* / Q000627:therapeutic use
D016632:Apolipoprotein A-I; D001055:Apolipoproteins B; D017270:Lipoprotein(a); D008074:Lipoproteins; D010959:Tissue Plasminogen Activator