Patients with familial hypercholesterolemia (FH) have elevated low-density lipoprotein cholesterol (LDL-C) levels and are at high risk of premature cardiovascular disease.1 Heterozygous FH (HeFH) is one of the commonest genetic disorders, and is more frequent among those with ischemic heart disease (IHD), atherosclerotic cardiovascular disease (ASCVD) and premature IHD.2 FH screening, followed by effective lipid-lowering therapy (LLT) including proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor can slow or even reverse plaque progression and reduce risk.3
Optical coherence tomography (OCT) is a promising intravascular approach in visualizing coronary plaque morphology, assessing disease progression, and monitoring response to treatments with high axial resolution (10–15 µm).4 Several related clinical trials have demonstrated that statins alone or in combination with PCSK9 inhibitors produce regression of atherosclerosis.5-7
Here, we presented a patient with premature IHD, who was a probable HeFH and received evolocumab (Repatha®) after percutaneous coronary intervention (PCI). We followed his clinical and laboratory results for over 3.5 years, and used OCT to monitor vascular response to PCSK9 inhibitor treatment.
A 34-year-old man with hyperlipidemia and hypertension self-presented to the emergency department due to exertional chest pain for 3 days on November 23, 2019. His height, body weight, and body mass index were 170 cm, 95 kg, and 32.9 kg/m2, respectively. Cardiac troponin I (cTnI) was mildly elevated at 0.297 ng/mL, and electrocardiogram demonstrated ST-T changes in I, aVL, II, III, aVF, V5–V9 leads, suggesting acute inferior, lateral, and posterior myocardial infarction. After medical stabilization, he underwent coronary angiography (CAG), revealing triple vessel disease (Figure 1) and received percutaneous transluminal coronary angioplasty to the left circumflex artery (LCX) with a stent on November 24, and another drug balloon dilation at posterior descending artery (PDA) on December 3. Standard postoperative treatment was given and the patient had no episodes of chest tightness accompanied by a regression of cTnI.
Laboratory examinations showed that his LDL-C and triglyceride (TG) levels were upper normal (Figure 2). Considering his LDL-C level remained at 3.45 mmol/L after combined oral LLT (statin + ezetimibe), we estimated his baseline LDL-C to be over 6.50 mmol/L. Besides, his father has a history of hyperlipidemia and PCI. According to the criteria of the Dutch Lipid Clinic Network (DLCN),8 the patient could be diagnosed as probable FH (his DLCN score = 8).
Based on early onset acute coronary syndromes (ACS) combined with multiple high-risk conditions, the patient could be defined as very high-risk ASCVD patient according to Americ