Aortic Regurgitation
Takahiro Shiota in 3D Echocardiography, 2020
The aortic root is the portion of the ascending aorta that lies between the sinotubular ridge superiorly and the bases of the valve leaflets inferiorly. The aortic root must be considered as a single functional entity.2–4 This includes the sinuses, the aortic valve leaflets, the commissures, and the interleaflet triangles (Figure 10.1). The leaflets are attached in a semilunar fashion at the upper boundary of the root called the sinotubular junction. Their lower part located below the anatomical ventriculoarterial junction defines the base of the aortic root. From a hemodynamic point of view, they represent the separation between the left ventricle and the aorta. The sinuses are the expended portion of the root below the sinotubular junction. They are named according to the coronary arteries arising: right coronary, left coronary, and noncoronary sinus. The definition of the annulus varies. The imaging “annulus,” frequently called the virtual ring, corresponds to the most basal insertion of the leaflet and is considered as the reference measurement, for determination of aortic size does not correspond to the true anatomical “annulus” referring to a semilunar crown-like structure demarcated by the hinges of the aortic leaflets.5 Because the anatomical ventriculoarterial junction could not be delineated by imaging, frequently, the measurement at the level of the virtual ring is considered as the ventriculoarterial measurement.6
Aortic Valve Mechanics
Michel R. Labrosse in Cardiovascular Mechanics, 2018
The AV is classically divided into different structures to make the description easier (Berdajs, 2015). The so-called aortic root is the biological structure at the transition between the left ventricular outflow tract and the ascending aorta. This transition is a complex and mixed structure, both part of the left ventricle from a physiological point of view and part of the aorta from a morphological point of view. The aortic root is mainly composed of the three sinuses of Valsalva located between the ventriculoaortic junction (VAJ) and the sinotubular junction (STJ). The three sinuses of Valsalva are outwardly ballooned regions of the aortic wall (Figure 9.1a), with an approximately hemispherical shape (Thubrikar, 1989). Two of these sinuses include orifices for the coronary arteries. There is a leaflet or cusp inside each sinus of Valsalva (Sauren et al., 1980).
The systematic approach
Paul F. Jenkins in Making Sense of the Chest X-ray, 2013
Figure 1.9 summarizes the mediastinal structures to be examined. I start with the aortic root. Is the aortic root of normal size? If it is small, this may indicate an atrial septal defect and you should seek (proactive ‘problem-solving’) the ancillary radiographic appearances of this diagnosis – namely, prominent hilar shadows and exaggerated vascular markings in the lung fields (Figs 1.9 and 1.10).If the aortic root is prominent, the commonest reasons are hypertension or degenerative unfolding of the aorta. Prominence may be associated with thoracic aortic dissection and, although the appearance is uncommon, always look for a ‘double-shadow’ within a prominent aortic arch. Be aware though that the chest X-ray in aortic dissection is usually normal (see Hazard and Fig. 1.11).
A review of pulmonary autograft external support in the Ross procedure
Published in Expert Review of Medical Devices, 2019
Vincent Chauvette, Marie-Ève Chamberland, Ismail El-Hamamsy
The aortic root is a complex and dynamic structure composed of the annulus, aortic valve cusps, sinuses of Valsalva and sino-tubular junction. During the cardiac cycle, each of these constituents change their shape and size in coordinated fashion. The intricate modifications to this functional unit have a direct impact on the pattern of flow across the aortic root, left ventricular workload, coronary blood flow reserve and stress distribution on the aortic cusps [8,9]. Some of the benefits observed after the Ross procedure might be explained by the fact that the pulmonary autograft root, when implanted in the aortic position, maintains its structural unity, therefore allowing the autograft to change its size and shape throughout the cardiac cycle in ways similar to a native aortic root [10–12]. Nevertheless, the sudden change from a low-pressure system to a high-pressure environment can result in histologic changes that lead to autograft dilatation. The idea of providing external support to the pulmonary autograft offers a solution to this problem by preventing dilatation. Various techniques of pulmonary autograft stabilization have been described; each presenting advantages and limitations.
Contemporary Review of the Ross Procedure
Published in Structural Heart, 2021
Vincent Chauvette, Laurence Lefebvre, Marie-Ève Chamberland, Elbert E. Williams, Ismail El-Hamamsy
The aortic valve is often considered a passive structure, which opens and shuts in response to changes in trans-valvular pressures. Instead, the aortic valve, a component part of the aortic root, is a dynamic and living structure with many important functions which contribute to optimizing coronary flow reserve, reducing left ventricular workload during systole and ensuring perfect hemodynamics across the aortic root both at rest and with exercise.9 In addition, aortic valve cusps are covered by a monolayer of endothelial cells, which produce nitric oxide, thereby inhibiting platelet aggregation.10 Along with interstitial cells in the body of the cusps, they can also mount an inflammatory reaction in response to bacterial organisms in the bloodstream, limiting the risk of infective endocarditis in normal aortic valves.2,11,12 Finally, the cellular components allow the valve to repair itself and reorganize its extracellular matrix over a lifetime without wear (~2.5 billion cardiac cycles in a normal lifetime).12
FEVR findings in patients with Loeys-Dietz syndrome type II
Published in Ophthalmic Genetics, 2018
Mark A. Solinski, Michael P. Blair, Harry Dietz, David Mittelman, Michael J. Shapiro
His past medical history was notable for a prenatal diagnosis of bilateral clubfoot and a dilated and tortuous aorta on maternal ultrasound. He was born after a full term of gestation. After birth, the patient showed cleft palate and bilateral finger contractures. MRI revealed dilated anterior part of the lateral ventricle. Ultrasound revealed dilated extrarenal pelvis. Echocardiogram noted patent ductus arteriosus, patent foramen ovale, and spontaneous pneumothorax. The aortic root diameter measured 2.4 cm (z-score of 3.77). Further examination showed exotropia, lumbar kyphosis, crumpled ears, frontal bossing, bifid uvula with cleft soft palate, slight retrognathia, lateral deviation of the fingers, mild adduction of the feet, dolichocephaly, craniosynostosis, malar hypoplasia, orbital hypertelorism, widely spaced teeth, arachnodactyly, translucent skin, pes planus, increased elbow extension, and basilar invagination with C2-C3 instability. His height charted at the 95th percentile. The clinical diagnosis of LDS was established on the basis of the skin findings, skeletal and craniofacial features, and aortic root dilation. At 8 months, genetic analysis found a mutation in TGFBR2 (p. R528H) and confirmed LDS Type II. Parental testing showed the mutation was acquired de novo. Surgical interventions included aortic root replacement at 9 months, strabismus surgery at 14 months old, cleft palate repair at 17 months, and a second aortic root replacement with valve replacement at 9 years.
Related Knowledge Centers
- Aorta
- Aortic Arch
- Aortic Sinus
- Aortic Valve
- Thoracic Aorta
- Sternum
- Ventricle
- Costal Cartilage
- Thoracic Aortic Aneurysm
- Reference Range