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Z. RYCHTER
In Fig. 5, the diagrams show, incidentally, three of the various
possibilities for the beginning of the carotid artery in experimentally
changed aortic arch patterns. First (6 D 3s4s), the left carotid origin
descends to the left 6th aortic arch and receives, therefore, blood from
FIG. 5. Some two- and three-clip combinations as examples of patterns resulting from a
mere summation of single suppressions. Examples of \^arious beginnings of the left
carotid artery are also shown.
the right ventricle. This occurs too in the case illustrated in Fig. 5b,
where the suppressed left 6th aortic arch constitutes the proximal part
of the left carotid in the same manner as previously described for 4 S
after elimination of 3s. The left pulmonary artery is its recurrent branch
(Fig. 5b—Ps). In Fig. 5a the left carotid artery is prolonged by the
entire dorsal aorta.
After suppression of both 6th aortic arches (Fig. 6a), however, a
second additional arcus aortae consistently developed from the left 4th
FIG. 6. The first and third combination is analogous to cases in Fig. 5. 6i)6s presents a
special pattern, b—transposition of the additional arcus aortae from 4s into the right
ventricle.