Relation of Proprotein Convertase Subtilisin/Kexin Type 9 to Cardiovascular Outcomes in Patients Undergoing Percutaneous Coronary Intervention

The pharmacological inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) has been shown to drastically affect low-density lipoprotein cholesterol levels and associated cardiovascular diseases. However, the potential effectiveness of PCSK9 serum levels as a biomarker for cardiovascular risk remains unclear. Serum PCSK9 levels in patients who underwent percutaneous coronary intervention (PCI) may predict long-term outcomes. PCSK9 levels were measured in 749 consecutive patients with coronary artery disease undergoing PCI. These patients were classified into 2 groups according to their serum levels of PCSK9. The primary end point was a composite of the major adverse cardiac events (MACE), including cardiac death, myocardial infarction, stroke, and any revascularization. The median PCSK9 level was 302.82 ng/ml. During a median follow-up of 28.4 months, a total of 38 (5.1%) MACE was recorded, and 50 (6.7%) patients died from any cause. Multivariate Cox regression analysis showed that compared with a lower serum PCSK9 level, a higher serum PCSK9 level was independently associated with a higher rate of MACE (adjusted hazard ratio 2.290, 95% confidence interval 1.040 to 5.045, p = 0.040) and all-cause death (adjusted hazard ratio 2.511, 95% confidence interval 1.220 to 5.167, p = 0.026). Results were consistent after propensity-score matching (MACE, adjusted HR 2.236, 95% CI 1.011-5.350, p = 0.047; all-cause death, adjusted HR 2.826, 95% CI 1.258-6.349, p = 0.012). Baseline serum PCSK9 levels were associated with long-term cardiovascular clinical outcomes and mortality during the long-term follow-up after PCI in patients with coronary artery disease.