Mumbai hospital performs coronary angioplasty on a 10-year old with a rare lipid disorder.

Mumbai: Familial hypercholesterolaemia (FH) is a primary genetic dyslipidemia characterized by elevation in serum low-density lipoprotein cholesterol and its deposition in systemic arteries, which causes premature atherosclerosis. In the latest issue of European Heart Journal, Deshpande et al (from Sion Hospital, Mumbai) report a unique case of a paediatric patient with FH and acute coronary syndrome treated with percutaneous coronary intervention to left main coronary artery and left circumflex artery using provisional stenting technique. Revascularization strategies for symptomatic coronary artery disease in paediatric patients with FH have multiple unique challenges which are highlighted in this case report.

Familial hypercholesterolaemia (FH) is an autosomal dominant genetic dyslipidaemia, which in its homozygous form affects 0.2% of the population. It is usually managed with lipid-lowering drugs (statins, cholesterol absorption inhibitors, PCSK9 inhibitors, etc.) and lipid apheresis. Coronary revascularization may be necessary when ischaemia-producing coronary disease develops.

A 10-year-old girl presented with severe symptomatic coronary artery disease. She complained chest pain since 1 month which had increased since 1 day to severe angina at rest. Multiple painless, firm nodules were present over her elbows, knuckles, knees, and ankles, suggestive of tendon xanthomas; moreover, she presented with corneal arcus.

The electrocardiogram (ECG) showed sinus tachycardia, normal axis, 3 mm ST segment depression in leads II, III, aVF, V4–V6 with biphasic T waves and 1.5 mm ST-segment elevation in lead aVR, 1 mm ST-segment elevation in V1 (aVR > V1) suggesting left main coronary artery disease. 2DEcho was suggestive of mitral valve prolapse with moderate MR.

Her lipid profile showed highly elevated total cholesterol level of 1010 mg/dL, high-density lipoprotein cholesterol of 62 mg/dL, LDL-C of 898 mg/dL, very-LDL cholesterol of 50 mg/dL and total triglycerides of 250 mg/dL. Her troponin I level was elevated.

A diagnosis of definite FH was made (total score 23), based on the Dutch Lipid Clinic Network diagnostic criteria for FH. She was managed with intravenous unfractionated heparin infusion, dual antiplatelet agents [Aspirin (5–8 mg/kg) and Clopidogrel (1–2 mg/kg)], Rosuvastatin 40 mg OD, Ezetimibe 10 mg OD, and anti-anginals.

The patient underwent coronary angiography which showed critical ostial left main coronary artery stenosis and non-critical lesions in LAD. LCX showed an ostial lesion and a bifurcation lesion in mid LCx. The left internal mammary artery (LIMA) had an 80% stenosis at its ostium. The left renal artery also showed an 80% stenosis.

The patient underwent the procedure under general anaesthesia with right femoral artery access, using provisional bifurcation stenting strategy. LMCA TO LCx stenting was done followed by stenting to mid LCx.

The patient was haemodynamically stable post-procedure and was initiated on dual antiplatelets, Rosuvastatin 40 mg OD, Ezetimibe 10 mg OD, and PCSK 9 inhibitor (Injection Evolocumab 420 mg subcutaneous once a month). Her 60-day follow-up lipid profile showed a reduction in total cholesterol levels to 640 mg/dL from 1010 mg/dL and a reduction in LDL-C to 508 from 898 mg/dL. Her renal artery stenosis and peripheral vascular disease were managed medically.

The optimal approach for management strategy for CAD in pediatric FH patients, such as coronary artery bypass grafting (CABG) vs. PCI, DES vs. bioabsorbable scaffolds among others and the optimal timing for these interventions in such patients with stable angina is unknown.

Coronary artery bypass graft was not feasible in this patient because of stenosed LIMA. Coronary artery stenting poses unique challenges in paediatric patients such as an increased risk of in-stent restenosis. This may occur because of the small diameter of the stents required or because of undefined differences in vascular healing responses in this population. A metallic stent may become undersized because of a child's growth (a four-fold increase in the diameter of the left main coronary artery occurs between infancy and 17 years of age) and the presence of a metallic stent may alter the coronary physiology.

Percutaneous coronary intervention by provisional stenting technique in this patient resulted in technical success and good short-term clinical outcome. Long-term follow-up and further research on coronary revascularization in paediatric FH are needed to guide the interventional management in this subset of patients.

Source: European Heart Journal: https://doi.org/10.1093/ehjcr/ytab175