Prospective evaluation of the relationship between platelet-leukocyte conjugate formation and recurrent myocardial ischemia in patients with acute coronary syndromes.
Platelet-leukocyte conjugates are increased in patients with coronary artery disease but the relationship between conjugate formation and myocardial ischemic outcome is unknown. We prospectively evaluated the relationship between conjugate formation and the development of recurrent myocardial ischemia in patients with acute coronary syndromes (ACS). Platelet-leukocyte conjugate formation (induced by thrombin receptor activating peptide (TRAP)) and platelet aggregation (induced by ADP and arachidonic acid) were assessed in 30 patients with unstable angina or non-ST elevation myocardial infarction. All patients were treated with beta-blockers, aspirin, heparin, and GPIIb-IIIa antagonists and were followed for in-hospital recurrent myocardial ischemia. Troponin I and C-reactive protein (CRP) were also measured. Seven patients (23%) experienced recurrent ischemia. Platelet-neutrophil conjugates were greater in ischemic patients (59 +/- 9 and 36 +/- 4%, P = 0.007, for + ischemia and -ischemia, respectively). Platelet aggregation did not differ between ischemic and nonischemic patients, and there was no significant relationship between aspirin resistance and ischemic outcome. Troponin I was greater in patients who developed recurrent ischemia (3.04 +/- 1.73 vs. 0.70 +/- 0.21 ng/ml, P = 0.03, for +ischemia and -ischemia, respectively) but CRP was not. TRAP-induced platelet-neutrophil conjugate formation was an independent predictor of ischemic outcome (OR 1.07, 95% CI 1.00-1.15, for each 1% increase in conjugate formation). Receiver operator characteristic analysis showed platelet-neutrophil conjugates to have good ability to discriminate between ischemic and nonischemic patients (AUC of 0.84, P < 0.05). TRAP induced platelet-neutrophil conjugate formation is related to in vivo ischemic risk in ACS patients.
Division of Cardiac Surgical Intensive Care, Department of Anesthesiology adn Critical Care Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21287, USA. nfaraday@jhmi.edu
Nauder
N
Faraday
Joel B
JB
Braunstein
Alan W
AW
Heldman
Everlie D
ED
Bolton
Kelly A
KA
Chiles
Gary
G
Gerstenblith
Steven P
SP
Schulman
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D000789:Angina, Unstable / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D016718:Arachidonic Acid / Q000494:pharmacology; D001241:Aspirin / Q000627:therapeutic use; D001792:Blood Platelets / Q000187:drug effects / Q000473:pathology*; D002097:C-Reactive Protein / Q000032:analysis; D002449:Cell Aggregation / Q000187:drug effects; D004351:Drug Resistance; D000077542:Eptifibatide; D005260:Female; D006493:Heparin / Q000627:therapeutic use; D006801:Humans; D007962:Leukocytes / Q000187:drug effects / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000473:pathology; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000209:etiology*; D009504:Neutrophils / Q000473:pathology; D018579:Patient Selection; D010455:Peptides / Q000627:therapeutic use; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000037:antagonists & inhibitors; D011446:Prospective Studies; D012372:ROC Curve; D018179:Receptors, Thrombin / Q000378:metabolism; D012008:Recurrence; D000077466:Tirofiban; D016896:Treatment Outcome; D019210:Troponin I / Q000097:blood; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000627:therapeutic use
D000319:Adrenergic beta-Antagonists; D010455:Peptides; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D018179:Receptors, Thrombin; D019210:Troponin I; D016718:Arachidonic Acid; D014443:Tyrosine; D000244:Adenosine Diphosphate; D006493:Heparin; D002097:C-Reactive Protein; D000077466:Tirofiban; D000077542:Eptifibatide; D001241:Aspirin