Download valve annuli and its circumference is divided into three segments of

Miguel del Río, M.D.; Domingo Liotta, M.D.
valve annuli and its circumference is divided into
three segments of 120° each annulus (fig. 8).
Approximately 45% of the circumference of the annuli is
attached to the left ventricular muscle (interventricular
septum) and 55% to the fibrous tissue (22-23) (See: Shape
of the aortic root).
The sinotubular junction (aortic ridge), is the narrowing
“rim-like” or sometimes “shelflike” transition from the
sinuses of Valsalva to the ascending aorta proper (fig. 1).
Using a strict anatomical criterion the sinoventricular
junction is the aortic ring formed by three hemi-ellipses,
which resembles the crown of a king (McAlpine,
Anderson, etc). However, in measurements by diagnostic
method, the sinoventricular junction is a circumferential
line that runs along the three nadir points of the aortic
root (fig. 9), being the latter the “aortic annuli” used in
surgical practice.
The aortic and pulmonary roots have similar anatomic
features but in the aortic root, the noncoronary sinus and
its leaflet is larger than the right and left sinuses (fig. 7
and fig. 9) (22, 24). The sinuses and leaflets of the
pulmonary root have the same dimension. The aortic annuli
does not vary its size in relation with the eventual
modifications in size of the left ventricle. The pulmonary
annuli is distensible and increases its circumference when
the volume of the right ventricle is augmented. The
sinotubular junction of the pulmonary valve (pulmonary
ridge) is measured by echocardiography to determine the
reliable diameter of the pulmonary annuli (25).
b- SIZE OF THE NORMAL AORTIC ROOT.
McAlpine (22), describes and measures the aortic root
of 100 specimens. The left anterior trigone is the smallest
and the intervalvular is the largest. The attachment of the
right aortic annulus to the ostium of the left ventricle is more
extense than the left aortic annulus (Tables 5, 6) (figs. 6,7).
The height of the sinus rim above the nadir of the
annulus (n°1) is greater than the annular height (n°2)
and the leaflet height (n°3) (Tables 5, 6) (fig. 7). The
coronary orifices are normally found in a line between
the upper extremities of the annuli. The upper extremities
of the adjoining aortic annuli are in contact with each
other through a distance of 6 mm, forming the annular
commissures (Tables 5, 6) (fig. 7).
Circumferences of the aortic valve were measured in
765 normal hearts from autopsy specimens ranging from
20 to 99 years old (392 women and 373 men). These
“in rigor mortis” measurements corresponded to
ventricular systole with a diameter of the aortic ring of
20.7 mm in 20-29 year-old men and 19.1 mm in women
of the same age.
In 50-59 year-old men the diameter is 23.6 mm and
Table 6 - Aortic annuli of 100 specimens. Measurements in millimeters.
Mean SD
1- Length
51 5
2- Attachment to Ostium
a) Right Annulus
To the left of the nadir
12 3
To the right of the nadir
4
3
b) Left Annulus
7
3
c) Posterior
10 2
Table 5 - Dimensions of the fibrous trigones of 100 specimens.
Right anterior
Left anterior
Left
Intervalvular
(RAFT)
(LAFT)
(LFT)
(IVT)
Height-mm Base-mm Area-mm2
11
20
18
6
5
9
7
8.4 x 8.3
27
12
23
59
Values without decimal fraction.
Reproduced from: McAlpine WA. Heart and Coronary Arteries.
Springer-Verlag Berlin – Heidelberg, 1976.
Women
Men
Women
Men
20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Circumference
57
Diameter
18.1
Circumference
61
Diameter
19.4
Circumference/m2
36
Diameter calculated/m2 11.5
Circumference/m2
32.3
Diameter calculated/m2 10.3
60
19.1
65
20.7
36.7
11.7
34
10.8
65
20.7
69
22
38.1
12.1
36.2
11.5
69
22
74
23.6
41.1
13.1
40.3
12.8
Women: 392 Men: 373 Range: 20 to 99 years old
Data: mm.
Modified from Scholz DG et al. Mayo Clin Proc 1988; 63:126-136.
10
6 - 18
2 - 13
2 - 19
6 -18
Values without decimal fraction.
SD: standard deviation.
Reproduced from: McAlpine WA. Heart and Coronary Arteries.
Springer-Verlag Berlin – Heidelberg, 1976.
Table 7 - Aortic annuli measured in 765 autopsy specimens from normal hearts.
Age- decades
Range
37 - 67
73
23.2
81
25.8
44.9
14.3
42.4
13.5
75
23.9
84
26.7
47.9
15.2
47.7
15.2
79
25.1
85
27
52.9
16.8
51.3
16.3
79
25.1
85
27
56.7
18
52.4
16.7
ANATOMIC AND FUNCTIONAL ASPECTS OF THE AORTA
22 mm in women and it dilates progressively with
increasing age. The mean circumference and diameter
of the aortic ring were almost always greater in men
than in women in each decade. When these
circumferences were indexed by the body surface area
values were greater in women (26ª, 26b) (Table 7).
Angiography and echocardiogram are the best methods
for the estimation “in vivo” of the dimensions of the aortic
root. In both studies, it is necessary to specify at what
moment of the cardiac cycle the measurement was
obtained. A good method to evaluate and measure the
aortic root is by Magnetic Resonance Imaging (MRI)(27).
The measurements of the aortic annuli at the end
diastole with TTE show augmentation of the diameter
with the increasing of age, corporal body surface, weight
and height. Diameters measure only a few millimeters at
birth and reach an average of 25 mm at 60 years old.
(10) (fig. 10). Krovetz et al (28) recalculated the data of
various reports, particularly Suter´s data (2,719 necropsy
specimens). In these data reanalyzes, the aortic valve
size increases almost linearly with age, and body surface
area does not seem to be a good normalizing factor for
the aortic valve size. On the other hand, Reed et al (29)
found that in subjects who exceed the 95th percentile of
height the relationship between aortic size and body
surface area tends to become a plateau. The use of any
criterion of linearity will overestimate aortic root
dimension in this gender subgroup.
The left ventriculogram is more reliable than the
aortography. It lets us estimate with greater accuracy
the size of the aortic annuli (30) (fig. 11).
In the left ventriculogram in RAO 30º and LAO 60º
projection (32 frames per second) the diameters of the
aortic annuli, the aortic ridge, the height of each sinus of
Valsalva and the equator of the sinuses of Valsalva were
measured (31) (figs. 12-14) (Tables 8, 9). The study
covered a 48 ± 9.3 (DS) year-old population.
Figure 10
The growth curve of the normal aortic root
diameter from birth to 60 years old. The
solid line represents the mean; the
interrupted line represents 1 standard
deviation (SD) and the dotted line
represents 2 standard deviations.
Reproduced from: El Habbal M, Somerville J.
Am. J. Cardiol.1989; 63: 322-326.
Figure 11
Drawing of the left ventriculogram in RAO
view. The right annulus (R), posterior (P),
and left (L) with junction of divisions of
the anterior leaflet of the mitral valve
(AVM) and the ostium of the left ventricle.
Reproduced from: McAlpine WA. Heart and
Coronary Arteries. Springer-Verlag Berlin –
Heidelberg, 1976.
11
1