Summary

Comprehensive update to ACC/AHA aortic disease guidance covering diagnosis, genetic evaluation, medical therapy, endovascular/surgical management, and surveillance of thoracic and abdominal aortic disease across asymptomatic, stable symptomatic, and acute presentations. Key changes include lowering the surgical threshold for sporadic root/ascending aneurysms from 5.5 cm to 5.0 cm at experienced Multidisciplinary Aortic Team centers, emphasis on indexed aortic measurements for small/large patients, expanded role of TEVAR in uncomplicated type B dissection, and routine first-degree relative screening for TAA/dissection.

Key Recommendations

Refer patients with complex aortic disease to centers with Multidisciplinary Aortic Teams; surgical mortality for proximal aortic surgery falls significantly at centers performing >20-25 cases/year and again at >50/year.
Screen first-degree relatives of patients with aortic root/ascending aneurysm or aortic dissection with aortic imaging, regardless of age.
Obtain genetic testing in TAD patients with syndromic features, family history of TAD, or onset before age 60; use multigene HTAD panel.
Use beta blockers as first-line antihypertensive in TAA; add ARB for combination therapy especially in Marfan syndrome.
Target SBP <130 mm Hg and DBP <80 mm Hg in patients with TAA or AAA; intensive control to <120 mm Hg may benefit selected patients.
Operate on sporadic aortic root/ascending aneurysms at ≥5.5 cm, or at ≥5.0 cm in experienced centers with Multidisciplinary Aortic Teams.
For acute type A dissection, transfer stable patients to high-volume aortic centers; perform open distal anastomosis rather than simple supracoronary interposition graft.
Manage uncomplicated acute type B dissection medically with anti-impulse therapy (IV beta blockers, target HR 60-80 and SBP <120 mm Hg); consider TEVAR for high-risk anatomic features or complicated presentations.
Repair AAA electively at ≥5.5 cm in men and ≥5.0 cm in women, with shorter surveillance intervals as diameter approaches threshold.
Screen men ≥65 years with smoking history (and selected women) for AAA with ultrasound.
In Marfan syndrome, replace aortic root at ≥5.0 cm, or at ≥4.5 cm with family history of dissection, rapid growth ≥0.3 cm/y, or before planned pregnancy.
Perform cesarean delivery in pregnant patients with aortopathy and significantly dilated aorta (>4.5 cm in Marfan); continue beta blockers throughout pregnancy and postpartum.

Thresholds & Doses

Sporadic root/ascending aneurysm surgical threshold: ≥5.5 cm (≥5.0 cm at experienced centers).
Rapid growth indication for surgery: ≥0.5 cm in 1 year or ≥0.3 cm/year over 2 consecutive years (sporadic); ≥0.3 cm in 1 year (HTAD or BAV).
Aortic dilation defined as ≥4.0 cm; aneurysm of ascending aorta as ≥4.5 cm.
Cross-sectional aortic area (cm²) to height (m) ratio ≥10 predicts increased risk; used as surgical indication.
Marfan syndrome aortic root replacement: ≥5.0 cm (≥4.5 cm with risk factors; before pregnancy if >4.5 cm).
Loeys-Dietz syndrome surgical thresholds: TGFBR1/TGFBR2 ≥4.5 cm (≥4.0 cm with high-risk features); SMAD3 ≥4.5 cm; TGFB2 ≥4.5 cm; TGFB3 ≥5.0 cm.
Turner syndrome: aortic size index (ASI) ≥2.5 cm/m² associated with increased dissection risk; ASI >2.0 cm/m² considered dilated.
BAV aneurysm repair: ≥5.5 cm generally; ≥5.0 cm with risk factors at experienced centers; ≥4.5 cm at time of concomitant AVR with low risk.
AAA repair threshold: ≥5.5 cm men, ≥5.0 cm women; rapid growth ≥0.5 cm/6 months or ≥1.0 cm/year.
AAA screening: men ≥65 with smoking history, ultrasound; AAA defined as aortic diameter >3.0 cm.
Descending TAA repair threshold: ≥5.5 cm; TAAA threshold ≥6.0 cm.
Acute type A dissection mortality: 1-2% per hour untreated; surgical mortality ~18% (IRAD).
IMH high-risk features: type A maximum diameter >45-50 mm, hematoma thickness ≥10 mm; type B maximum diameter >47-50 mm, hematoma thickness ≥13 mm.
PAU high-risk: maximum diameter ≥13-20 mm or depth ≥10 mm.
Kommerell diverticulum repair: orifice >3.0 cm or combined diverticulum+adjacent aorta diameter >5.0 cm.
Acute AAS heart rate target 60-80 bpm; SBP target <120 mm Hg.
AAA surveillance intervals: 3.0-3.9 cm every 3 years; 4.0-4.9 cm annually; ≥5.0 cm (men) or ≥4.5 cm (women) every 6 months.
GCA induction: prednisone 40-60 mg/d; taper to ≤5 mg/d by 1 year; add tocilizumab for refractory/relapsing disease.
Pregnancy: cesarean delivery if aortic diameter >4.5 cm in Marfan; avoid pregnancy if aortic root >4.5 cm.
Aortic graft infection: minimum 6 weeks IV antibiotics; consider lifelong oral suppression for retained prosthetic material.
LDL goal <70 mg/dL with high-intensity statin in atherosclerotic aortic disease.
Aspirin 75-162 mg daily for secondary prevention in atherosclerotic aortic disease.

Citations

Top 10 Take-Home Messages — surgical threshold lowering, multidisciplinary team care, screening of first-degree relatives
Section 2.3 — definitions of aortic dilation (≥4.0 cm) and aneurysm (≥4.5 cm) of root/ascending aorta
Section 4 — Multidisciplinary Aortic Team volume-outcome data
Section 6.1.2 — genetic aortopathies (Marfan, Loeys-Dietz, vEDS, Turner, HTAD genes) with gene-specific thresholds
Section 6.4 — medical management including beta blockers, ARBs, statins, BP targets
Section 6.5 — surgical/endovascular thresholds for aortic root, arch, descending TAA, TAAA, AAA
Section 7.3-7.4 — acute aortic syndrome medical management and surgical/endovascular treatment of type A and type B dissection
Section 8 — pregnancy management with condition-specific prophylactic surgery thresholds (Table 34)
Section 9.1 — large vessel vasculitis diagnosis and glucocorticoid/tocilizumab treatment algorithms