Platelet PlA2 polymorphism and platelet activation are associated with increased troponin I release after cardiopulmonary bypass.
BACKGROUND
The PlA2 polymorphism of platelet glycoprotein IIIa has been identified as a prothrombotic risk factor in a number of cardiovascular settings. The aim of this study was to determine whether the PlA2 polymorphism of platelet glycoprotein IIIa and degree of platelet activation were associated with more severe myocardial injury as indicated by troponin I release following cardiopulmonary bypass.


METHODS
The PlA2 genotype was determined in 66 patients undergoing elective coronary artery bypass grafting requiring cardiopulmonary bypass. Troponin I concentrations and the percentage of circulating, activated (CD62P+) platelets were measured at predetermined intervals perioperatively.


RESULTS
Forty-six patients were Pl(A1,A1), and 20 were Pl(A1,A2) or Pl(A2,A2). Patients with at least one PlA2 allele had significantly greater postoperative troponin I concentrations than PlA1 homozygotes (P = 0.006, analysis of variance). Peak troponin I concentrations also correlated significantly with the increase in circulating, activated platelets (P = 0.02, Spearman rank correlation).


CONCLUSIONS
The PlA2 allele of platelet glycoprotein IIIa is associated with higher troponin I concentrations following cardiopulmonary bypass surgery, suggesting that this platelet polymorphism contributes to perioperative myocardial injury.
Rinder
Christine S
CS
Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8051, USA. christine.rinder@yale.edu
Mathew
Joseph P
JP
Rinder
Henry M
HM
Greg Howe
J
J
Fontes
Manuel
M
Crouch
Jill
J
Pfau
Stephen
S
Patel
Parag
P
Smith
Brian R
BR
D000328:Adult; D000368:Aged; D000483:Alleles; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D039661:Integrin beta3 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation; D011110:Polymorphism, Genetic; D011183:Postoperative Complications / Q000209:etiology*; D013927:Thrombosis / Q000209:etiology; D019210:Troponin I / Q000378:metabolism*
D039661:Integrin beta3; D019210:Troponin I