p.108 抽出テキスト
10.1.4.2 ACTA2-related heritable thoracic aortic disease Pathogenic variants in the ACTA2 gene, encoding for smooth musclespecific alpha-actin (a critical component of the vascular smooth muscle cell contractile apparatus), lead to aortic aneurysms and dissections in non-syndromic patients.1496 Patients primarily present with type A or B aortic dissection, and with aneurysms that involve the root and/or ascending aorta. A subset of pathogenic variants predisposes to occlusive vascular diseases.1497 Surveillance is summarized in Recommendation Table 67 and Figure 41. TAAD may occur at aortic diameters <45 mm, and consideration of surgery at diameters <45 mm should be informed by the presence of additional clinical and genetic risk factors.1410 Genetic and imaging cascade screening of first-degree family members is an essential element of care, as treatable disease may otherwise be missed in family members—with fatal consequences. High risk features include: Known high risk genetic variants (R528H/C in TGFBR2) Women with TGFBR2 variants and small body size Severe extra-aortic features Aortic root surgery if risk factors (see box below) Aortic root surgery Family history of aortic dissection (especially at young age or relatively small aortic diameter) Aortic growth rate ≥3mm per year TGFBR2a,b 35 mm 40 mm 45 mm 50 mm 55 mm TGFBR1a TGFBR2a TGFBR1a Consider aortic root surgery Consider aortic root surgery SMAD3c,d TGFB2e,f,g TGFB3h,i Figure 42 Suggested thresholds for prophylactic aortic root/ascending replacement in Loeys–Dietz syndrome. From a1388, b1391, c1492, d1491, e1490, f1489, g1493, h1494, i1495. Recommendation Table 67 — Recommendations for imaging and surgery in ACTA2-related heritable thoracic aortic disease (see also Evidence Table 11) Recommendations Classa Levelb Annual monitoring of the aortic root/ascending aorta with TTE to evaluate aortic root/ascending aorta enlargement is recommended.1498 I C Imaging of the aorta with CMR/CCT every 3–5 years is recommended.1498 I C Prophylactic aortic root surgery should be considered with an aortic diameter ≥45 mm, or lower in cases with other risk factors.c,1499 IIa C © ESC 2024 CCT, cardiovascular computed tomography; CMR, cardiovascular magnetic resonance; TTE, transthoracic echocardiography. aClass of recommendation. bLevel of evidence. cRisk factors for aortic dissection: family history of dissection with no or minimal dilatation or young age; rapid growth ≥3 mm per year. ESC Guidelines 3645 Downloaded from academic.oup.com/eurheartj/article/45/36/3538/7738955 by guest on 07 October 2026