In all three carotid cases the murmur was troublesome, being audible to the patient at night when the head was rested on the side corresponding to the aneurism.
Expansile pulsation.—Pulsation in combination with the existence of a tumour is the main feature in the diagnosis between the conditions of pure varix and varicose aneurism. It was not always existent or prominent in the earliest stages, probably from temporary blocking of the artery, or from the diffuse and irregular nature of the cavity offering conditions unsuitable to the satisfactory transmission of the wave. When localisation had occurred it was always present.
Effects of Aneurismal Varix or Varicose Aneurism on the Circulation
(a) General.—The most striking feature in these injuries is the remarkable effect of the disturbance to the even flow of the circulation on the heart. This first struck me in two of the cases of carotid arterio-venous aneurism recorded below (Nos. 10 and 11). In these I was inclined at first to attribute the rapid and irritable character of the pulse solely to injury to the vagus, as in each laryngeal paralysis pointed to concussion or contusion of the nerve. The pulse reached a rate of 120-140 to the minute. This disturbance was not of a transitory nature, for in the two cases referred to the rapid pulse persists, in spite of entire recovery of the laryngeal muscles, and the fact that in one case the aneurismal sac has been absolutely cured, and in the second only a small sac remains, in each as a result of proximal ligature of the carotid artery. In the former a varix still exists, and at the end of seven months the pulse is still over 100. In the latter, in which a sac is still present, the pulse rate varies from 110 to 130. In each case the condition has now existed twelve months. My attention once directed to this point, I noted a similar acceleration of the pulse in the case of these aneurisms elsewhere; thus in a femoral aneurism the rate was 120, and in an axillary varix of twenty years' standing which came under my observation the pulse rate varied from 110 to 120, according to the position of the patient. Unfortunately I had not directed my attention to this point in the early series of cases which came under observation.
It will be remarked in cases 13 and 14 that at the expiration of a year the pulse rate was still high, but these again are cervical aneurisms each in contact with or near the vagus.
In a case of aneurismal varix of the femoral artery of three years' standing, which was under the charge of Mr. Mackellar, the pulse rate was normal. In this instance great dilatation of the vessels had occurred.
These observations raise the interesting question whether the irritable circulation which has been classically considered one of the predisposing causes of spontaneous aneurism should not rather be regarded as a result of the condition.
(b) Local.—In none of the cases of varix was the period of observation long enough to allow me to determine the development of dilatation of the arterial trunk above the point of obstruction. This, however, is the common sequence, and no doubt will occur in those patients who resume active occupation without operation.
The effects of either condition on the distal circulation were remarkably slight. The distal pulses were little, if at all, modified in strength or volume, and signs of venous obstruction, if present at first, disappeared with much rapidity. In one case (No. 15) of a large arterio-venous popliteal aneurism there was considerable swelling of the leg, but in this case the sac was large and situated at the apex of the space, and no doubt exercised external pressure on the vein.
In the case of the carotid aneurisms, especially that probably on the internal carotid, transient faintness was a symptom in the early stages of the case. All three of the cases recorded here, however, had been the subjects of very free hæmorrhage, either primary or recurrent.