Enhanced “In Vitro“ Release of Platelet α-Granules After Acute Myocardial Infarction (AMI)

Summary

In vivo platelet activity was studied in 58 patients with AMI on admittance to the Coronary Care Unit, in 48 of these patients after 1 week, in 30 after 1 month and in 24 patients after 6 months. Patients were carefully selected and excluded if they had associated diseases known to increase platelet activity. In vivo activation was studied by evaluating the plasma concentration of beta-thromboglobulin (β-TG) and platelet factor 4 (PF4) in the same blood sample. On admittance (x = 58.5) and on day 7 (x = 52.9) β-TG values were significantly higher than those obtained in the control group (x = 29). β-TG values were moderately elevated after 1 month (x = 37.7) and then returned to values similar to those of the control group after 6 months (x = 27.9). The simultaneous assessment of PF4 shows a β-TG/PF4 ratio indicative for in vitro release (≤2.5) in many patients on days 1 and 7. Moreover, the β-TG/PF4 ratio in patients with AMI tends towards 2 when β-TG values are high. These results may indicate a greater tendency to an in vitro platelet release in the acute phase of AMI.

Keywords

β-TG - PF4 - AMI

• References

• 1 Turpie AGG, de Boer AC, Genton E. Platelet consumption in cardiovascular disease. Semin Thromb Haemostas 1982; 08: 161-185
• 2 Kaplan KL, Owen J. Plasma level of β-thromboglobulin and platelet factor 4 as indices of platelet activation in vivo. Blood 1981; 57: 199-202
• 3 Ludlam CA, Cash JD. Studies on the liberation of β-thromboglobulin from human platelets in vitro. Br J Haematol 1976; 33: 239-247
• 4 Nossel HL, Wasser J, Kaplan KL, La Gamma KS, Yudelman I, Canfield RE. Sequence of fibrinogen proteolysis and platelet release after intrauterine infusion of hypertonic saline. J Clin Invest 1979; 64: 1371-1378
• 5 Musial J, Neviarowski S, Edmunds LH, Addonizio VP, Nicolau KC, Colman RW. In vivo release and turnover of secreted platelet antiheparin proteins in Rhesus Monkey (Macaca Mulatta). Blood 1980; 56: 596-603
• 6 Rasi V, Ikkala E, Torstilla I. Plasma β-thromboglobulin in acute myocardial infarction. Thromb Res 1982; 25: 203-212
• 7 Handin R, McDonough M, Lesch M. Elevation of platelet factor 4 in acute myocardial infarction: measurement by radioimmunoassay. J Lab Clin Med 1978; 91: 340-348
• 8 Levine SP, Lindenfeld J, Ellis JB, Raymond NM, Krentz LS. Increased plasma concentration of platelet factor 4 in coronary artery disease. Circulation 1981; 64: 626-631
• 9 Wadenvik H, Eriksson KA, Safai-Kutti S, Swedberg K, Kutti J. Plasma concentration of platelet factor 4 in acute myocardial infarction. Scand J Haematol 1981; 26: 359-363
• 10 Hughes A, Daunt S, Vass G, Wickes J. In vivo platelet activation following myocardial infarction and acute coronary ischemia. Thromb Haemostas 1982; 48: 133-135
• 11 Van Hulsteijn H, Kolff F, Briet E, Van der Laarse A, Bertina R. Fibrinopeptide A and β-thromboglobulin in patients with angina pectoris and acute myocardial infarction. Am Heart J 1984; 107: 39-45
• 12 Pumphrey CW, Dawes J. Plasma β-thromboglobulin as a measure of platelet activity. Am J Cardiol 1982; 50: 1258-1261
• 13 Smitherman TC, Milam M, Woo J, Willerson JT, Frenkel EP. Elevated beta-thromboglobulin in peripheral venous blood of patients with acute myocardial ischemia: direct evidence for enhanced platelet reactivity in vivo. Am J Cardiol 1981; 48: 395-402
• 14 O’Brien JR, Therington E, Shuttle Worth R. Beta-thromboglobulin and heparin neutralizing activity test in clinical conditions. Lancet 1977; 01: 1153-1154
• 15 Denham MJ, Fisher M, James G, Hassan M. Beta-thromboglobulin and myocardial infarction (Letter). Lancet 1977; 01: 1154
• 16 Mehta P, Mehta J. Platelet function studies in coronary artery disease. V. Evidence for enhanced platelet microthrombus formation activity in acute myocardial infarction. Am J Cardiol 1979; 43: 757-760
• 17 Schwartz MB, Hawiger J, Timmons S, Friesinger GC. Platelet aggregates in ischaemic heart disease. Thromb Haemostas 1980; 43: 185-188
• 18 Kohanna FH, Smith MH, Salzman EW. Do patients with thromboembolic disease have circulating platelet aggregates?. Blood 1984; 64: 205-209
• 19 Sorkin RP, Tokarsky JM, Huber-Smith MJ, Steiger JF, McCann DS. In vivo platelet aggregation and plasma catecholamines in acute myocardial infarction. Am Heart J 1982; 104: 1255-1261
• 20 White AM. Contribution of platelet to thrombus formation. Br Med Bull 1978; 34: 123-128
• 21 Stratton JR, Malpass TW, Ritchie JL, Pfeifer MA, Harker LA. Studies of platelet factor 4 and Beta-thromboglobulin release during exercise: lack of relationship to myocardial ischemia. Circulation 1982; 66: 33-43
• 22 Douglas JT, Lowe GDO, Forbes CD, Prentice CRM. Plasma fibrinopeptide A and beta-thromboglobulin in patients with chest pain. Thromb Haemostas 1983; 50: 541-542