Republished review: Surgical management of aortic root disease in Marfan syndrome and other congenital disorders associated with aortic root aneurysms

Abstract

Elective root replacement in Marfan syndrome has improved life expectancy in affected patients. Three forms of surgery are now available: total root replacement (TRR) with a valved conduit, valve sparing root replacement (VSRR) and personalised external aortic root support (PEARS) with a macroporous mesh sleeve. TRR can be performed irrespective of aortic dimensions and a mechanical replacement valve is a secure and near certain means of correcting aortic valve regurgitation but has thromboembolic and bleeding risks. VSRR offers freedom from anticoagulation and attendant risks of bleeding but reoperation for aortic regurgitation runs at 1.3% per annum. A prospective multi-institutional study has found this to be an underestimate of the true rate of valve-related adverse events. PEARS conserves the aortic root anatomy and optimises the chance of maintaining valve function but average follow-up is under 5 years and so the long-term results are yet to be determined. Patients are on average in their 30s and so the cumulative lifetime need for reoperation, and of any valve-related complications, are consequently substantial. With lowering surgical risk of prophylactic root replacement, the threshold for intervention has reduced progressively over 30 years to 4.5 cm and so an increasing number of patients who are not destined to have a dissection are now having root replacement. In evaluation of these three forms of surgery, the number needed to treat to prevent dissection and the balance of net benefit and harm in future patients must be considered.

Keywords: AORTA; CARDIAC SURGERY; GREAT VESSELS AND TRAUMA.

Figure 1

Acute aortic dissection in a man in his 50s from a family with Marfan syndrome and a history of several dissections and root replacements. One of the kidneys is not being perfused.

Figure 2

Relationship between age and the aetiology of aneurysms of the ascending aorta.

Figure 3

Cardiac magnetic resonance images. Dark blood spin-echo image (left) and a diastolic frame from complete cine acquisition (right) of severe aortic root dilatation of typical Marfan morphology with type A dissection and functional severe eccentric AR and LV dilatation. The aortic root diameter is 8 cm.

Figure 4

Aortic roots with the characteristic morphology and distal displacement of the coronary orifices but without gross enlargement. The CT image (left) is a volume rendered image of an ECG-gated scan of the thoracic aorta. The CMR image (right) is a thin section from a 3D steady-state in free precession sequence acquired in the left anterior oblique projection.

Figure 5

Personalised external aortic root support. BCA, brachiocephalic artery; LCA, left coronary artery; RCA, right coronary artery.

Figure 6

Aortic root diameter over a 20-year period in a woman with Marfan syndrome; the diameter continued to enlarge during a first pregnancy and thereafter to reach the accepted threshold of 45 mm. She requested referral for personalised external aortic root support (PEARS). Her aortic dimensions were reduced as was seen in eight of the first 10 PEARS operations.