Prevalence of factor XII (Hageman factor) deficiency among 426 patients with coronary heart disease awaiting cardiac surgery

BACKGROUNDSeveral case reports of myocardial infarction in patients with factor XII deficiency have been published. In the present study we investigated the prevalence of this condition. METHODSFactor XII activity (one-stage clotting assay), fibrinogen (derived method), and lipoprotein (a) (enzyme-linked immunosorbent assay) were measured in the plasma of 426 consecutive patients with coronary heart disease awaiting cardiac surgery. RESULTSAmong the 426 patients, 44 (10.3 %) were found to be moderately deficient in factor XII (factor XII activity 17–50%, antigen 15–57%). The prevalence of factor XII deficiency was significantly higher (P < 0.0001) among patients with coronary heart disease than among 300 healthy blood donors (2.3%). Among coronary heart disease patients with this deficiency, elevated levels of fibrinogen, lipoprotein (a), and blood pressure were no more prevalent than in those without the deficiency; nor were cigarette smoking or a positive family history of thromboembolism more prevalent. CONCLUSIONSCoronary heart disease patients showed a 10% prevalence of factor XII deficiency. However, the pattern of atherosclerotic risk factors did not differ between patients with or without the deficiency.