ELEVATED SERUM LIPOPROTEIN(A) IS A RISK FACTOR FOR CLINICAL RECURRENCE AFTER CORONARY BALLOON ANGIOPLASTY

Background Elevated lipoprotein (Lp) (a) concentrations are associated with coronary artery disease and myocardial infarction. Lp(a) is stru cturally related to proteins involved in lipid transport, fibrinolysis , coagulation, and cellular mitogenesis and is known to have important physiological interactions with the coagulation and fibrinolytic syst ems. Because these processes may be important to arterial healing afte r balloon injury, we hypothesized that elevated Lp(a) concentrations m ay be associated with recurrence of symptoms and restenosis after ball oon angioplasty. Methods and Results We assessed 240 consecutive patie nts undergoing coronary balloon angioplasty with measurements of Lp(a) , total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, apolipoprotein A-I, and apolipoprotein B-100 concentrations from fresh specimens. Patients were evaluated 4 to 6 months after angioplasty fo r clinical recurrence by repeat angiography if angina had returned or by maximal exercise treadmill testing with thallium imaging if patient s remained asymptomatic. Ninety-seven patients (40%) had clinical recu rrence; 143 (60%) did not. Patients with recurrence had significantly greater Lp(a) concentrations compared with those without (median, 29 v ersus 14; P<.0001). Each patient quintile stratified by increasing Lp( a) concentrations had incrementally greater recurrence rates ranging f rom 27% (lowest quintile) to 60% (highest quintile). By multivariate l ogistic regression analysis, Lp(a) concentration was the only predicto r of recurrence (P<.0001). A subset of frozen, stored serum samples sh owed a significant decrease in measured Lp(a) concentration over time (mean, 605 days; P<.01). Conclusions An elevated Lp(a) concentration w as a risk factor for clinical recurrence after percutaneous translumin al balloon coronary angioplasty. Other lipid levels or clinical charac teristics were not significantly associated with recurrence. When seru m was frozen and stored for a prolonged period, Lp(a) concentration de creased over time.