Release patterns of pregnancy‐associated plasma protein A in patients with acute coronary syndromes assessed by an optimized monoclonal antibody assay

Abstract

Objective. Pregnancy‐associated plasma protein A (PAPP‐A) is expressed in eroded and ruptured atheromatous plaques, and circulating levels are elevated in acute coronary syndromes (ACS). Our objective was to investigate release patterns of PAPP‐A in ACS and whether they differ among different types of ACS. Methods. In 40 patients, PAPP‐A concentrations were measured in serially collected samples assessed by a novel ELISA technique. The patients were grouped according to type of ACS. Results. Release patterns for ST elevation myocardial infarction (STEMI) patients who underwent primary percutaneous coronary intervention (pPCI) showed a single substantial PAPP‐A increase shortly after pPCI, followed by an abrupt return to normal levels without secondary peaks. STEMI, high‐risk and low‐risk non‐ST elevation myocardial infarction/unstable angina pectoris (NSTEMI/UAP) patients without pPCI showed highly variable patterns with primary peaks followed by secondary PAPP‐A increases. All patients with elevated PAPP‐A levels reached the upper reference level within 24 h. There was a significant difference in median peak levels between STEMI (23.2 mIU/L) and low‐risk ACS patients (6.35 mIU/L) (p = 0.004) and between high‐risk (median = 15.3 mIU/L) and low‐risk ACS patients (p = 0.01). Among high‐risk ACS patients, NSTEMI patients had significantly higher peak levels than UAP patients (p = 0.003). Conclusion. PAPP‐A serum levels increase above normal values within 24 h after onset of symptoms in ACS. There are significant differences in PAPP‐A peak levels and release patterns across the spectrum of ACS patients.

• Atherosclerosis
• cardiovascular disease
• coronary thrombosis
• myocardial ischaemia
• angioplasty transluminaly percutaneous intervention