Plaque characteristics and serum pregnancy-associated plasma protein A levels predict the no-reflow phenomenon after percutaneous coronary intervention.

Objectives: To investigate the relationship between serum plasma pregnancy-associated plasma protein A (PAPP-A) and coronary plaque characteristics, and their prognostic value for coronary no-reflow after percutaneous coronary intervention (PCI). Methods: Patients with unstable angina undergoing PCI were divided into a normal reflow group and a no-reflow group after stent deployment. Coronary blood flow was measured angiographically; plaque components were detected by virtual histology intravascular ultrasound. Serum PAPP-A and high-sensitivity C-reactive protein (hsCRP) were measured before PCI. Cardiac troponin T (cTnT) was measured before and 24 h after PCI. Results: A total of 166 patients with unstable angina undergoing PCI were included: normal reflow group (n = 145) and no-reflow group (n = 21), after stent deployment. Baseline coronary blood flow was similar in the two groups. The no-reflow group had plaques with less-fibrotic tissue and a larger necrotic core, more thin-cap fibroatheromas and plaque ruptures, and higher serum PAPP-A, hsCRP and post-PCI cTnT levels than the normal reflow group. Serum PAPP-A was correlated negatively with plaque fibrotic area and positively with necrotic core area. Conclusion: High serum PAPP-A and plaque lesions with a large necrotic core are associated with the no-reflow phenomenon after PCI, in patients with unstable angina.