History of Hypertension and Enhanced Thrombogenic Activity in Postinfarction Patients

Abstract

Hypertension is a risk factor for coronary thrombosis and death in cardiac patients mediated in part by endothelial damage or dysfunction and increased thrombogenicity. However, there are no data regarding the association between hypertension and thrombogenic activity in stable patients after myocardial infarction and limited data about the prognostic significance of thrombogenic factors in hypertensive patients after infarction. Therefore, levels of thrombogenic, lipid, and inflammatory factors were measured 2 months after an acute myocardial infarction in 461 hypertensive and 582 nonhypertensive patients. Thrombogenic factors included d-dimer, fibrinogen, plasminogen activator inhibitor-1, von Willebrand factor, factor VII, and factor VIIa. Lipid variables included cholesterol (total, HDL, LDL), triglyceride, lipoprotein (a), apolipoprotein-A1, and apolipoprotein-B. The prognostic significance of these factors for predicting cardiac events during a 2-year follow-up was evaluated in hypertensive and nonhypertensive patients. In comparison with nonhypertensive patients, those with hypertension had higher levels of d-dimer (607 versus 453 mg/L, P<0.001), fibrinogen (3.64 versus 3.43 g/L, P<0.001), plasminogen activator inhibitor-1 (29.7 versus 27.3 ng/mL, P=0.01), von Willebrand factor (159 versus 141 IU/dL; P<0.001), and higher levels of inflammatory markers (hsCRP and SAA). In multivariate analysis after adjustment for clinical covariates, elevated d-dimer was the only factor independently associated with a history of hypertension (OR, 1.38, P=0.05). d-Dimer was associated with an increased risk of recurrent cardiac events in both hypertensive (hazard ratio=3.02, P=0.005) and nonhypertensive (hazard ratio=2.42, P=0.02) patients. Thus, patients after infarction with a history of hypertension have enhanced thrombogenic activity, which predisposes them to recurrent cardiac events.