close

Вход

Забыли?

вход по аккаунту

?

The coronary blood supply in the cat.

код для вставкиСкачать
T H E CORONARY BLOOD SUPPLY I N T H E CAT
DAVID I. ABRAMSON, J. HAMILTON CRAWFORD AND
GEORGE H. ROBERTS1
Biooklyn, New P o r k
FOUR FIGURES
It is the purpose of this report to present a description of
the coronary blood supply in the cat as revealed by injection
of the blood vessels.
Seventy normal hearts were used; no special attention
being paid to the age of the animals. The coronary arteries
were filled with an injection mass consisting of plaster of
Paris and pulverized colored chalk. The hearts were then
washed free of any excess injection mass, dehydrated and
cleared in oil of wintergreen, following the technique advocated by Gross.2
RIGHT CORONARY ARTERY
The right coronary artery arises from the aorta and extends to the right for a short distance to enter the auriculoventricular groove, in which it runs over the anterior surface
of the heart, around the margo acutus (lateral border of the
right ventricle) and then posteriorly. I n about two-thirds of
the specimens, it gives off near its origin a conus branch
which crosses the base of the pulmonary artery to divide into
fine twigs. Further along in its course, six or seven other
branches arise, four or five of which run downward over the
anterior surface of the right ventricle, while the remaining
two extend over the margo acutus. These perpendicular
branches, in turn, give off fine vessels to either side which
anastomose with one another on the outer wall of the right
ventricle.
From the Department of Physiology, Long Island College of Medicine.
* Gross, L. : The blood supply t o the heart. New York, Iloeber, 1921.
25
26
I). I. ABRAMSON, J. H. CRAWFORD A N D G. I€. ROBERTS
Posteriorly the right coronary artery remains in the
anricnlo-ventricular groove for variable distances. I n about
33 ycr cent of cases it plays an unimportant role in supplying
the posterior surface of the heart. I n this series (fig. 1) it
either tiiriis to run down the right ventricle parallel to and
to the right of the posterior interventricular sulcus, or it
gradually terminates by dividing into braiiches which extend
2
Fig. 1 Posterior surface of heart. A , posterior descending branch of circumflex artery running in interventricular suleus ; B, right coronary artery.
Fig. 2 Posterior surface of Iiexrt. A, circumflex division of left coronary
artery ; R, large branch of circumflex division extending over inargo obtusus.
f o r short distances over the lateral basal portion of the posterior surface of the right ventricle. I n the remaining 65 per
cent of cases, the right coronary artery supplies posteriorly
all of the right ventricle and variable portions of the left
ventricle (fig. 3). I n about one-half of this series, it turns
abruptly a t the posterior interventricular groove and, a s the
posterior descending artery, runs almost perpendicularly
downward in the direction of the apex. During its course in
CO1:ONABY BLOOD SUPPLY I N THE CAT
27
the posterior groove i t gives off several branches to either
side and also a number of small twigs which, arising from
the under surface of the main branch, penetrate the septum at
right angles. I n the remaining half of the series (i.e. of the
65 per cent of cases) the right coronary artery continues on
to the posterior surface of the left ventricle, giving off at the
3
Fig. 3 Posterior surfncc of heart. A , right coroiiary artery exteiidinp on t o
basal portion of left veiitricle ; R, p s t e r i o r tlesccnding division of right coronary
artery rumiiiig in i~itervcntricular sulcus ; C, perpendicular twig of circumflex
division of tlw left eoroiiary artery ; D, circumflex division of left coronary
artery.
Fig. 4 Anterior surface of henrt. A , anterior descending division of l e f t
coronary artcry ruimiiig i n the anterior intervcntricul:ir sulcus ; €3, coiius branch
of auterior desceiidiug division.
point where it crosses the posterior interventricular groove,
one o r two large branches which follow practically the same
course and ramification as the posterior descending artery
(fig. 3 B ) . The right coronary artery, itself, in these cases
eventually divides into small branches which coiirse obliquely
d o ~ v i i u ~over
d the left ventricle to supply from one-quarter
to one-half of its posterior surface adjoining the interventricular groove (fig. 3 A ) .
28
D. I. ABRAMSON,
J. H.
CBAWFORD A N D G. H. ROBERTS
LEFT CORONARY ARTERY
The left coronary artery arises from the aorta, turns to
the left to run in the auriculo-ventricular groove for a short
distance, and then divides into its two main branches, the
anterior descending and circumflex arteries.
Circzhmflex artery. The Circumflex artery continues in the
groove, proceeding to the left over the anterior surface and
around the obtuse border of the left ventricle. I n a number
of instances, it gives off near its origin one or two branches
which in their course almost bisect the angle formed by the
anterior descending and circumflex arteries. I n some hearts
it is difficult to determine whether these vessels arise from
one o r the other of the subdivisions of the left coronary artery,
or from the main branch itself. They extend obliquely downward over the anterior surface of the left ventricle for varying distances, some ending on the anterior surface, while
others reach the obtuse border of the heart and then course
in the direction of the apex. F u r t h e r along, the circumflex
gives off a variable number of branches, two o r three of which
extend almost perpendicularly downward over the anterior
surface of the left ventricle, while one o r two course over the
margo obtusus. Of the latter, one is usually rather large,
its terminal branches continuing as far a s the apex of the
left ventricle (fig. 2 B ) .
I n its posterior course there arise from the circumflex a r tery three to four branches which extend downward over the
surface of the left ventricle (fig. a), the circumflex itself
remaining in the auriculo-ventricular groove for varying distances. I n 65 per cent of cases, it leaves the auriculo-ventricular groove at some point between the obtuse border of
the heart and the posterior interventricular groove. I n these
instances it either gradually terminates by dividing into two
or three branches which extend f o r short distances over the
posterior surface of the left ventricle, or the main vessel itself
runs down over the ventricle, giving off twigs to either side
and ending about midway between base and apex. I n all
of these hearts, branches from either the right coronarJ- a r -
CORONARY BLOOD SUPPLY I N THE CAT
39
tery, its posterior descending division, or from both, course
over the posterior surface of the left ventricle (fig. 3 ) . In
the other 35 per cent of cases the circumflex artery remains
in the auriculo-ventricular groove until it reaches the posterior interventricular groove in which it proceeds toward
the apex a s the posterior descending a r t e r y (fig. 1A ) . During its course, the latter gives off a number of branches which
either extend on to the basal portion of the posterior surface
of the right ventricle, supply the adjoining portion of the left
ventricle, or penetrate the septum at right angles. I11 some
specimens the circumflex artery leaves the auriculo-ventricnlar groove a short distance to the left of the posterior interventricular groove and in these cases it runs down the posterior surface of the left ventricle parallel to the groove.
Aiztcrior desceizdiizg artery. A t its origin the anterior descending artery leaves the auriculo-ventricular groove and
turns abruptly downward to run for variable distance in the
subepicardial fat overlying the anterior interventricular
groove (fig. 4). I n the majority of cases it breaks up into
its sub-branches at a point about two-thirds the distance from
base to apex ; however, in some hearts the division takes place
in the upper third of the anterior interventricular sulcus. In
the latter instances there a r e usually two terminal branches,
one of which continues in the sulcus almost a s far a s the apex,
while the other extends obliquely to the left over the anterior
surface of the left ventricle. Both give off twigs which supply the lower halves of the right and left ventricles adjoining
the sulcns. In those hearts in which the division of the anterior descending artery takes place at the lower level, the
terminal branches, also two in number, continue downward,
one remaining in the sulcus and the other generally extending
somewhat to the left.
Near its origin, the anterior descending artery in about twothirds of the cases, gives off one or two branches to the right
which extend across the lower border of the conus arteriosus
and then break up into fine twigs (fig. 4). These, in a number
of hearts, course a short distance downward over the part of
30
I). I. ABRAMSON, J. H. C R A W F O R I l A N D G. H. ROBERTS
the riglit ventricle close to the anterior sulcus. Other large
branches, varying in number from three to six, also arise from
the right side of the anterior descending artery a t intervals
and a r e distributed over the adjoining portion of the right
ventricle a s f a r a s its apes. F r o m the left side of tlie artery
three to seven vessels arise which extend on to the anterior
aspect of the outer wall of the left ventricle, some running
horizontally toward the obtuse border, others descending
obliquely in the direction of the apes. From these, in turn,
arise numerous fine vessels wliicli extend over a great part
of the anterior surface of the left ventricle to aiiastomosc
with branches from the circumflex artery. Twigs which penetrate the septum for varying distances a r e given off also from
the under surface of tlie anterior desceiidiiig artery.
SUMMARY
The coronary blood vessel distribution in the cat was investigated in seventy injected hearts.
On tlie outer surface of the heart anteriorly, the arrangement was found to be relatively constant. Generally, the right
ventricle was supplied by tlie perpendicnlar branches of tlie
right corollary artery (except for a strip adjoining the anterior interventricular sulcus), the left ventricle by branches
of the left coronary artery.
Posteriorly, the blood vessel distribution varied. I n 65
per cent of cases the right coronary artery supplied all of
the riglit ventricle and varying portioiis of the left ventricle
adjoining the posterior interventricular sideus, the rest of
the left ventricle receiving its supply from the left coronary
artery. I n the remaining 35 per cent of cases the left coronary artery supplied all of the left ventricle and the adjoining
part of the riglit ventricle, while the riglit coroiiary supplied
only a small p a r t of the riglit ventricle.
In the majority of cases, the septum received its supply
from peiietratiiig braiiches of both right and left corollary
arteries, while in tlie remaining hearts, wholly from braiiclics
of the latter.
Документ
Категория
Без категории
Просмотров
2
Размер файла
717 Кб
Теги
cat, supply, coronary, blood
1/--страниц
Пожаловаться на содержимое документа