Evaluation of coronary CT angiography and echocardiographic findings in children with homozygous familial hypercholesterolemia

Objective: This study aimed to evaluate coronary computed tomography angiography (CTA) and echocardiographic findings together in children with homozygous familial hypercholesterolemia (HoFH) to investigate the presence of early subclinical atherosclerosis and its relationship with clinical and laboratory parameters. Materials and Methods: Sixteen genetically confirmed HoFH patients who underwent coronary CTA and were followed up at the Department of Pediatric Metabolism and Nutrition, Çukurova University Faculty of Medicine, were retrospectively analyzed. Demographic characteristics, clinical features, biochemical parameters, echocardiographic, and coronary CTA findings were evaluated. All patients had mutations in the LDLR or LDLRAP1 genes. Results: The mean age of the patients was 12.5 ± 3.0 years; 37.5% were male and 62.5% female. Parental consanguinity was present in all cases. The mean LDL-C level at diagnosis was 490.4 ± 212.0 mg/dL, and the mean LDL-C level at the time of coronary CTA was 347.1 ± 163.6 mg/dL. Aortic stenosis was detected in 18.8% (n=3) of the patients aged 12, 12, and 18 years. Those with aortic stenosis had significantly higher baseline LDL-C levels (710.0 ± 217.4 vs. 439.7 ± 183.0 mg/dL; p=0.042). No coronary calcification was detected, and all Agatston scores were zero. Echocardiography revealed aortic valve involvement in one patient (6.3%), while other parameters were within normal limits. Among patients with aortic stenosis on CTA, 33.3% also showed aortic valve involvement on echocardiography (p=0.032). Serum 25(OH)D levels were low in all patients (mean 9.9 ± 4.5 ng/mL). Patients receiving lipid apheresis had significantly higher baseline LDL-C levels than those not receiving apheresis (668.8 ± 199.5 vs. 430.9 ± 187.1 mg/dL; p=0.048). Conclusion: This study demonstrates that coronary CTA can detect early aortic wall narrowing and subclinical cardiac involvement before the development of calcification in children with HoFH. Elevated LDL-C levels are significantly associated with aortic stenosis. While echocardiography is useful for assessing systolic function, coronary CTA is superior in identifying early atherosclerotic changes. Regular echocardiography combined with periodic coronary CTA follow-up is crucial for detecting early cardiac involvement and optimizing treatment strategies in children with HoFH.