both posterior tibial arteries were felt and the right dorsalis pedis vessel had become palpable for the first time, but at that date the left dorsalis pedis remained undetectable. T h e blood-pressure, five months after the operation, in the right arm was 146/82 mm., in the left arm 126/100 mm., and in the right tibial vessels, as ascertained by palpation of the dorsalis pedis artery, 82 systolic. On screening the heart the left ventricle was still prominent, but cleared the spine in the left anterior oblique position. T h e aortic knuckle was placed very high in the chest, as seen in the right semi-oblique position. I n the anteroposterior view the aorta barely cleared the left spinal border. It would, therefore, appear that the result of the operation had been to improve very definitely the circulation through the aorta, for the systolic pressure of the right arm has been reduced, the collateral circulation has nearly disappeared, and the arterial supply to the right foot is clearly better.A further point worthy of note is that previous to operation a definite diastolic murmur was audible to the left of the sternum, and this was in 1945 taken to indicate an aortic valve incompetence. When a patent ductus arteriosus was found at operation, this murmur was naturally ascribed to this. Following operation, at which the distal end of the patent ductus arteriosus was removed, together with the coarctation and part of the vestigial left subclavian artery, it was assumed that the diastolic murmur would disappear. I n fact, the murmur has remained and still has the high-pitched quality characteristic of aortic regurgitation. This introduces a complication from the medical point of view, and it is conceivable that the explanation is to be found in the fact that the present case may be an example of coarctation of the aorta combined with a minor degree of subaortic stenosis and aortic insufficiency, a triad of abnormalities which is well recognized. A further point in favour of this is the persistence of the systolic apical murmur conducted to the aortic base.
CONCLUSIONSA case of coarctation of the aorta with great difference between the blood-pressures of the arm is recorded. This difference was due to a vestigial condition of the left subclavian artery. A successful anastomosis was performed between the proximal and distal ends of the aorta after excision of the coarctation.Five months later the patient was in normal, active health, with an improving circulation to the lower limbs, and the abnormal psychological behaviour present before the operation appeared to have improved.