The efficacy of a PCSK9 inhibitor for the plaque stabilization in the non-culprit lesion of ACS patients by using near-infrared intravascular ultrasonography

Abstract Background and purpose In acute coronary syndrome (ACS) patients, major cardiovascular events during follow-up were equally attributable to recurrence at the site of culprit lesions and to non-culprit lesions, and mostly occurred within one year. Recent studies showed that Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitor significantly reduces the risk of cardiovascular events. However, the rigorous effects of PCSK9 inhibitor in patients with ACS, especially for the stabilization of plaque in the non-culprit lesions has not been identified. The purpose of this study was to evaluate the efficacy of a PCSK9 inhibitor for the plaque stabilization in the non-culprit lesion of ACS patients. Methods We retrospectively analyzed the 10 ACS patients (STEMI:5 cases, NSTEMI:1 case, and UAP:4 cases) who had non-culprit lesions and were injected with a PCSK9 inhibitor. We analyzed 11 non-culprit lesions before and after PSCK9 injections by using a near-infrared intravascular ultrasonography (NIRS-IVUS). Results The follow up intervals were 229.4±82.9 days. Major cardiovascular events did not occur in all patients. The serum low-density lipoprotein (LDL) cholesterol levels were significantly decreased form 128±36.7 mg/dl to 26.7±7.4 mg/dl (P