A prospective study of the role of lipoprotein(a) in the pathogenesis of unstable angina.

Abstract

Lipoprotein(a) is considered to be a risk factor for atherothrombotic diseases. The aim of the study was to examine the potential role of lipoprotein(a) concentrations in patients admitted with unstable angina with particular reference to their cardiac Troponin T concentrations, which identifies a subgroup at high risk of subsequent cardiac events. Consecutive patients admitted with chest pain to a single coronary care unit were studied. One hundred and sixty-seven patients had a final diagnosis of unstable angina, of whom 56 were cardiac Troponin T-positive. Admission lipoprotein(a) concentrations were significantly higher in the cardiac Troponin T-positive unstable angina group as compared to the cardiac Troponin T-negative unstable angina group: median and interquartile ranges 22.25 mg.dl-1 (6.25, 32.0) vs 6.0 mg.dl-1 (2.22, 14.8) respectively) P = 0.0004. A highly significant correlation was also found between the level of cardiac Troponin T at diagnosis and the lipoprotein(a) concentration: rs = 0.2798, P = 0.0001. This study provides the first evidence in man of a significant role for lipoprotein(a) in unstable angina. The correlation between lipoprotein(a) concentration and cardiac Troponin T concentration suggests that lipoprotein(a) may be significantly involved in the early failure of plaque rupture stabilization.