Aims: Unstable coronary atherosclerotic plaque can be present in patients with chronic stable coronary artery disease (CAD). Our objective was to assess whether measurement of plasma pregnancy-associated plasma protein (PAPP-A) level, a reflection of plaque instability, in patients with chronic stable CAD had an independent prognostic value on the subsequent incidence of death, acute coronary syndrome (ACS), and revascularization.
Methods and results: Patients referred for coronary angiography were recruited. A cohort of 103 patients with stable symptoms for at least 6 weeks and with a coronary angiogram showing at least a 50% luminal diameter narrowing formed our study population. Median follow-up was 4.9 years. Mean age was 65+/-10 years. In a multivariable model that included CAD traditional risk factors, ejection fraction, extent of coronary atherosclerosis, prior history of myocardial infarction, prior revascularization, discharge medications, and C-reactive protein, the plasma PAPP-A was found to be significantly associated with the endpoint of future death [adjusted hazard ratio (HR) 5.29; 95% CI 1.27-22.0; P=0.023] and with the endpoint of future death and ACS (adjusted HR 3.56; 95% CI 1.27-10.0; P=0.015), but not with the endpoint of future death and revascularization.
Conclusion: Measurement of plasma PAPP-A level in patients with chronic stable CAD has an independent prognostic value on the occurrence of death and ACS.