A Chromogenic Substrate Assay Kit for Factor XII: Evaluation and Use for the Measurement of Factor XII Levels in Cardiopulmonary Bypass Patients

• Published in: Thrombosis research Vol. 94; no. 2; pp. 103 - 109
• Main Authors: Gallimore, Michael J., Jones, D.W., Wendel, Hans P.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Ltd 15.04.1999; Elsevier Science
• Subjects: Adult; Aged; Biological and medical sciences; Cardiopulmonary Bypass; Chromogenic Compounds; Chromogenic substrate assay; Coronary Disease - blood; Coronary Disease - surgery; Evaluation Studies as Topic; Factor XII; Factor XII - analysis; Humans; Male; Medical sciences; Middle Aged; Reagent Kits, Diagnostic; Sensitivity and Specificity; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the heart; Cardiopulmonary bypass; Chromogenic substrate assay; CPB, cardiopulmonary bypass; FXIIct, factor XII clotting activity; FXIIcs, factor XII determined by chromogenic substrate assay; FXIIag, factor XII antigen; FXII, factor XII; DDAVP, desamino D-arginine vasopressin; Factor XII; Heart; Human; Blood coagulation; Homograft; Exploration; Blood plasma; Aortocoronary; Bypass; Surgery; Graft; Circulatory system; Coagulation factor
• ISSN: 0049-3848; 1879-2472
• DOI: 10.1016/S0049-3848(98)00202-3

Factor XII levels were determined in plasma samples from 75 patients before undergoing aortocoronary bypass grafting and from 40 healthy age-matched donors by using a microtitre plate adaptation of a new chromogenic peptide substrate assay kit for factor XII. The chromogenic peptide substrate assay values for factor XII correlated well with those obtained in clotting r=0.90; y= 15.811+0.8236 x and immunochemical r=0.88; y=17.90+0.817 x assays in the normal donor samples. Factor XII levels in the patients were significantly lower than those in the normal donors 83.3±23.2% versus 103.4±23.1; p=0.004 , and nine patients (12%) had factor XII values below 50% compared with only one of the normal donors (2.5%). Factor XII levels and kallikrein-like activities (a measure of contact system activation) were followed before, during, and one day after cardiopulmonary bypass in 20 patients. Factor XII levels were significantly reduced, and kallikrein-like activities significantly elevated after 5 and 30 minutes cardiopulmonary bypass. One day after cardiopulmonary bypass both factor XII levels and kallikrein-like activities were significantly lower than preoperation values.