The rotational position of the aortic root related to its underlying ventricular support

Abstract

We aimed to assess the relationship of the rotational position of the aortic root to its underlying ventricular support, and to the position of the inferior margin of the membranous septum, which serves as a surrogate of the atrioventricular conduction axis. We analyzed 40 normal heart specimens (19 children, 21 adults). The inferior margin of the membranous septum was measured relative to the virtual basal ring. The rotational position of the aortic root was determined by assessing the relationship of the aortic leaflet of the mitral valve to the interleaflet triangle between the non-and left coronary leaflets. The extent of supporting fibrous versus myocardial tissues was measured. We also performed a similar investigation of 30 adult computed tomographic data sets. The median age was 0.25 years (44% male) for children, and 64 years (33% male) for adults. The aortic root was positioned centrally in 22 specimens (55%), rotated counterclockwise in 6 (15%), and clockwise in 12 (30%). In the setting of counterclockwise rotation, 53.4% (median) of the supporting circumference was myocardial, as opposed to 41.4% (median) in those with centrally positioned roots, and 31.9% (median) in those with clockwise rotation (P < 0.0001). The position of the inferior margin of the membranous septum was not associated with the rotational position. Analysis of the 30 adult computed tomographic data sets (median age 66.5 years, 57% male) confirmed the positive relationship between clockwise rotation of the aortic root and an increase in the extent of fibrous as opposed to myocardial support. The rotational position of the aortic root correlates with variation in the extent of its fibrous as opposed to myocardial ventricular support, but not with the position of the inferior margin of the membranous septum relative to the virtual basal ring.

Vulnerability of the ventricular conduction axis during transcatheter aortic valvar implantation: A translational pathologic study

“…It is now accepted that clinical measurements need to acknowledge these variations, including the angle of its inferior margin. (Amofa et al, 2019; Faroux et al, 2020; Jørgensen et al, 2022; Tretter et al, 2018) Failure also to account for the variation on the location of the aortic root within the base of the left ventricle (Figure 9), which to the best of our knowledge have not previously received attention, may serve to underestimate the risk of iatrogenic injury. (Tretter et al, 2019) Our findings suggest that this variation, now measureable using clinical techniques (Figure 7), dictates the relationships of the aortic valvar sinuses to the ventricular components of the conduction axis.…”

“…The rotation of the root within the base of the left ventricle was determined according to the relationship of the interleaflet triangle between the left and non‐coronary leaflets to the midline of the aortic leaflet of the mitral valve. (Amofa et al, 2019; Tretter et al, 2018) Clockwise rotation, as opposed to a central position of the aortic root, or counterclockwise rotation, was then determined as viewed from the apex of the left ventricle. We also used the 3D datasets to measure the angle of the crest of the muscular ventricular septum relative to the plane of the virtual basal ring.…”

Pseudoaneurysm of the mitral‐aortic intervalvular fibrosa following endocarditis and aortic valve surgery in an infant—Case report and exhaustive systematic review of pediatric cases

“…The aortic valve lies central with the other valve rings attached to it (Figure 8). The mitral‐aortic intervalvular fibrosa (MAIVF) is a fibrous curtain which spans between the right and left fibrous trigones of the cardiac skeleton, creating fibrous continuity between the anterior leaflet of the mitral valve and the noncoronary leaflet of the aortic valve, and a variable portion of the left coronary leaflet 37,38 . An out‐pouching in this area does not typically contain layers of muscular tissue and is histologically more appropriately classified as a pseudoaneurysm.…”

Diversity and determinants of the sigmoid septum and its impact on morphology of the outflow tract as revealed using cardiac computed tomography

“…The relationships between the aortic root axis and left ventricular axis, extent of rotation of the aortic root, right anterior tilting of the aortic root, and extent of aortic wedging were measured using the aortic-to-left ventricular axial angle, rotation angle, anterior aortic tilting angle, and wedged height, respectively, using a previously validated method (Figure 2). [19][20][21][22][23][24][25][26][27] Specifically, a larger rotation angle indicated clockwise rotation of the aortic root relative to the virtual basal ring, as viewed from the left ventricular direction. A smaller tilting angle indicated a more tilted ascending aorta toward the right anterior direction.…”

“…to re-evaluate its potential diversity and impact on the left ventricular outflow tract morphology. Furthermore, we assessed the structural anatomy of the aortic root, including its age-related rotation, tilting, wedging, and dilatation, [19][20][21][22][23][24][25][26][27] to reveal the morphological background of the sigmoid septum.…”