Murmurs may be present or absent in this congenital anomaly. They are easily understood, when the condition is complicated by a congenital heart lesion, but with a normal valvular apparatus they are dependent upon the autoehthonous oscillations of the wall of the aorta, which is dilated with each systole of the heart.
Continued low temperature of the body and aidema have frequently been noted.
Vierordt collected altogether 30 cases which came to autopsy, 21 of which were in males, 9 in females, but only one of these cases affected a child. Symptoms of loss of compensation belong to the period of life after the development of puberty.
3. Congenital Anomalies of the Large Vessels 0) Transposition of the Large Arteries According to Vierordt about 70 anatomically authentic cases of this anomaly have been described up to this time, the pathogenesis of which depends upon anomalous partition and position of the primary truneus arteriosus, which has several variations. according to Roki tansky. The most important is true transposition (transpositie rera), in vshich the aorta occupies the place of the pulmonary artery and vice versa (complete inversion). The semilunar valves change their posi tion with the transposition. The coronary arteries of the heart are then also abnormally placed. The transposed vessels may rise from one ventricle. or the aorta arises from both ventricles, in eqnal or unequal parts, just over the interventricular septum, which is defective in such eases. The pulmonary artery may arise in the same way.
So, too, the openings of the Vei11S into the auricles, like the large arteries, may have their positions changed, or the venm cavte and pul monary veins may open into one auricle only, when fretal communica tions will always persist between both circulations, in order to main tain the regular blood supply.
Defects in the septum usually exist with transposition of the arteries, somewhat more rarely the ductus Botalli persists, and sometimes, too, there are stenoscs of the ostia of the heart.
When the aorta rises from the right side of the heart, its walls are thicker than those of the left side of the heart. In many cases the calibre of the transposed vessels is abnormal, especially the pulmonary artery, when it rises from the left side of the heart, frequently appears abnormally wide; in one of Hochsinger's cases it WaS dilated as though by an aneurysm (Fig.109).
With transposition of the large vessels, collateral communications between the capillaries of the branches of the bronchial and pulmonary arteries are very commonly found within the lungs, when the bronchial arteries are dilated and carry venous blood from the venous aorta into the lungs, which blood then, in a partially arterialized condition, flows back into the right auricle again, through the bronchial veins.
The length of life in cases of congenital transposition of the vessels is very limited, according to Tarufii and Vierordt. Most cases do not survive the first six months. Of the 75 eases hitherto reported only 15 SW-6 Ved the second year of life. Exceptionally this anomaly is found between the twentieth aud fortieth years.
symptoms of this condition can only be expected from pure transpositions. In complicated cases, associated with var ious other anomalies, obstacles to the diagnosis arise which cannot be overcome. Transposition of the origin of the arteries or at least a pul monary artery arising from the left ventricle may he suspected if the second sound at the base of the heart is abnormally accentuated, with out any murmurs being heard at the base of the heart, with pure heart sounds and with high-grade cyanosis. The abnormal accentuation of the second sound at the pulmonary area depends upon increased pres sure within the pulmonary artery, supplied through the left ventricle, which is also under high pressure. If, besides, a murmur is heard in the third intercostal space to the left of the sternum, there is probably at the same time a defect in the interventricular septum (see. Pig. 110, in which the diagnosis was made by Hochsinger).
Most eases of transposition are distinguished by high-grade cyanosis, yet sometimes cases have been observed with slight cyanosis, or without any cyanosis at all.
Suffocative and convulsive attacks are frequently found in older children with dark blue cyanosis. The heart is almost always hyper trophied, and sometimes it is changed in position also, haNing a median position or one to the right side.