Abstract 15644: Clinical Impact of Achilles Tendon Ultrasonography for Diagnosis of Familial Hypercholesterolemia in Patients With Stent Implantation.

Background: Familial hypercholesterolemia (FH) is characterized by progressive arteriosclerosis due to a congenital increase of low-density lipoprotein cholesterol (LDL), and myocardial infarction and angina pectoris tend to develop in juvenile. Thus, early diagnosis and early intervention for FH is important, but the diagnosis rate of FH is extremely low. Achilles tendon thickness (AT-T), which is generally measured by soft X-ray radiography, is one of criterion for FH, but the imaging quality and radiation exposure in soft X-ray radiography are occasionally problems in clinical settings. Thus, in this study we investigated the clinical impact of ultrasonographic measurements in patients with stent implantation. Methods: We enrolled 50 consecutive patients who underwent stent implantation from October 2016 to September 2017 in our hospital. We measured AT-T using both soft X-ray radiography (X-AT-T) and ultrasonography (U-AT-T) at the same day. We also measured AT width (U-AT-W) and ratio of U-AT-W to U-AT-T (U-AT-ratio) using ultrasonograpy.. We evaluated the correlation between X-AT-T and U-AT-T. In addition, we evaluated the sensitivity and specificity to predict FH using each parameter. Results: There was significant correlation between X-AT-T and U-AT-T (y=0.75x-0.34, r=0.92, p<0.0001) (figure). FH group consisted of 5 patients. Using cut off value with 9mm as X-AT-T, 9.2mm as U-AT-T, 18.8mm as U-AT-W and 1.83 as U-AT-ratio, FH can be predicted with 100% sensitivity and 74% specificity, 100% sensitivity and 98% specificity, 80% sensitivity and 89% specificity and 100% sensitivity and 100% specificity, respectively. Cut off values using ultrasonographic parameters were determined by receiver-operating curves. Conclusions: It may be more important for detecting FH to measure not only thickness but also width of Achilles tendon. Thus, Achilles tendon ultrasonography is more useful to detect FH than soft X ray in the patients with stent implantation. [ABSTRACT FROM AUTHOR]