Clinical application of Doppler ultrasonography in the thoracic outlet syndrome.

Difficulties in diagnosing the thoracic outlet syndrome prompted a pilot study of noninvasive Doppler ultrasonography in 160 thoracic outlets of healthy volunteers. Encouraged by the results we applied the technique to the clinical evaluation of flow disturbances during various provocative maneuvers. Ninety-four thoracic outlets were examined; of these, 32 were operated upon. Severe flow occlusion which was detected by Doppler ultrasonography reproduced symptoms of which the patients had originally complained. All patients were relieved of their symptoms, and only five had minor flow disturbances after resection of the first rib and scalenotomy. Resection of cervical ribs was carried out in seven of nine patients with this anomaly. Doppler ultrasonography was found to be a most valuable diagnostic modality and its wider application in this field is recommended.

Identification and successful treatment of congenital microfistulas with the aid of directional Doppler.

Hitherto unidentifiable and therefore untreatable congenital microfistulas were detected with the aid of continuous-wave directional Doppler and a fine-beam pencil probe. The microfistulas formed part of the Klippel-Trenaunay (K-T) syndrome. The management of one case is reported in detail and in three others salient features are touched upon. Careful clinical and radiological examination failed to demonstrate any arteriovenous microfistulas. When Doppler ultrasound scanning was carried out, two discrete fistulas were discovered. Their extent and direction were mapped out accurately. Incisions were made directly over the markings displaying a pulsating capillary tuft of vessels. Further dissection exposed a feeding arteriole which was less than 1 mm. in diameter. Excision of the vascular malformations resulted in the cure of the patient. In another patient with the K-T syndrome in whom a cutaneous hemangioma involved the whole lower limb, in spite of a thorough and systematic search with a Doppler, no microfistulas could be demonstrated. It is suggested that all patients suffering from the K-T syndrome should be examined by Doppler ultrasound in the hope that microfistulas which elude radiodiagnostic techniques might be detected and treated surgically.

Noninvasive assessment of aorta-coronary saphenous vein bypass graft patency using directional Doppler.

Noninvasive monitoring of patency of aorta-coronary bypass grafts can be achieved with reasonable accuracy using the continuous wave directional Doppler and a pencil probe. The character of the graphic record and the auditory signal generated by the flow through these new vessels perfusing the myocardium are distinctive because of both the pattern of flow and also the fixed and relatively immobile position of these grafts in the anterior mediastinum. A total of 226 aorta-coronary bypass grafts were monitored in the first postoperative week: 82 to the right coronary artery (RCA), 90 to the left anterior descending (LAD), and 56 to the circumflex and lateral ventricular branches. Interpretation of patency in these latter vessels was consistently unreliable and was abandoned early in the study. This unreliability was probably due to their short superficial course and their juxtaposition to the aorta and the pulmonary artery. In contrast, flow through grafts to the RCA and the LAD could be established in approximately 90%. Of 82 grafts to the RCA, flow could not be detected in four (5%) and was doubtful in two (2%). In 90 grafts to the LAD, no flow was observed in four (4%) and was doubtful in five (6%). Comparing noninvasive Doppler results with angiography in 34 grafts, no false negatives were found, but there were two or 10% false positives. Flow characteristics in a functioning internal mammary implant were also found to be quite different from those in an intact opposite mammary artery. This form of monitoring requires some practice and experience but is quick, cheap and noninvasive. It offers an acceptable degree of accuracy in monitoring aorta-coronary bypass grafts to the RCA and the LAD when the conduits are in the anterior mediastinum.

A sterile technique for adjustment of intra-aortic balloon catheter position after closure of the groin incision.

Following insertion or prolonged pumping, intraaortic balloon position is occasionally found well below the desired site with the concomitant loss of mechanical advantage. Repositioning may mean having to advance a semisterile catheter into the arterial lumen. To alleviate this risk, a new technique of balloon catheter insetion is suggested whereby a 10 inch length of prosthetic material is sewn into the artery. The redundant length is allowed to protrude beyond the skin closure. If prolonged pumping is envisaged, the cuff may be left intact altogether or else it is amputated upon satisfying oneself that the balloon is placed in the desired position.