The diagnosis is suspected by history, physical examination, and Doppler studies and confirmed with arteriography.21 Therapy for arterial compression depends on its degree of involvement.
An asymptomatic patient with cervical or first rib arterial compression producing poststenotic dilatation of the axillary–subclavian artery should undergo rib resection, preferably through the transaxillary approach, removing the ribs, both first and cervical, without resecting the artery. The dilatation usually returns to normal after removal of compression.
Compression from the first or cervical rib producing aneurysm with or without thrombus should be treated with rib resection and aneurysm excision with graft placement through the supraclavicular and infraclavicular combined approach.
Thrombosis of the axillary–subclavian artery or distal emboli secondary to TOS compression should be treated with first rib resection, thrombectomy, embolectomy, arterial repair or replacement, and dorsal sympathectomy.
One-hundred and fifty-one patients with axillary–subclavian artery aneurysm and 62 patients with occlusion were treated successfully. Dorsal sympathectomy was performed when indicated. The bypass grafts37 were successful, with the exception of three that occluded and required reoperation and one that could not prevent amputation because of the time that had elapsed before the patient presented for therapy. No cerebrovascular accidents occurred.
Effort thrombosis of the axillary–subclavian vein, or Paget–Schroetter syndrome, is usually secondary to unusual repetitive use of the arm in addition to the presence of one or more compressive elements in the thoracic outlet (see Chapter 145). Historically, Sir James Paget38 in London in 1875 and Von Schroetter39 in Vienna in 1884 independently described this syndrome of thrombosis of the axillary–subclavian vein that bears their names. The word effort was added to thrombosis because of the frequent association with exertion, which produced either direct or indirect compression of the vein. The thrombosis is caused by either trauma or unusual occupations that require repetitive muscular activity. Typical occupations include professional athletes, linotype operators, painters, and beauticians. Cold and traumatic factors, such as carrying skis over the shoulder, tend to increase the proclivity for thrombosis. Elements of increased thrombogenicity also increase the incidence of this problem and exacerbate its symptoms on a long-term basis.40 In most patients with thrombosis of the axillary–subclavian vein, the costoclavicular ligament congenitally inserts further laterally than normal.
The axillary–subclavian vein traverses the tunnel formed by the clavicle anteriorly, the scalenus anticus muscle laterally, the first rib inferiorly, and the costoclavicular ligament medially (Fig. 143-9).41
Normal anatomy of the thoracic outlet with conventional insertion of the costoclavicular ligament on the first rib.
In patients with thrombosis of the axillary–subclavian vein (Paget–Schroetter syndrome), the costoclavicular ligament congenitally inserts further laterally than normal (Fig. 143-10). When the scalenus anticus muscle, which is lateral to the vein, becomes hypertrophied through activity and exercise, the vein is significantly narrowed. This is not the case when the costoclavicular ligament inserts in a normal place much more medially on the first rib, even when significant scalenus anticus muscle hypertrophy occurs.42
Congenital abnormal lateral insertion of the costoclavicular ligament on the first rib with hypertrophy of the scalenus anticus muscle (labeled anterior scalene muscle) lateral to the vein and thrombosis due to compression of the axillary–subclavian vein (Paget–Schroetter syndrome).
The diagnosis is suspected by a careful history and physical examination with Doppler studies and is confirmed by a venogram.
Intermittent or partial obstruction should be treated by first rib removal through the transaxillary approach with resection of the costoclavicular ligament medially, first rib inferiorly, and the scalenus anticus muscle laterally. The clavicle is left in place. The vein is decompressed, and all the bands and adhesions are removed.43,44
For many years, complete thrombosis Paget–Schroetter syndrome was treated by elevation of the arm and use of anticoagulants, with subsequent return to work. If symptoms recurred, the patient was considered for a first rib resection, with or without thrombectomy, as well as resection of the scalenus anticus muscle and removal of any other compressive element in the thoracic outlet, such as the costoclavicular ligament, cervical rib, or abnormal bands.21 Thirty-six patients were treated by this approach; only 10 ended with a good to excellent result.
Availability of thrombolytic agents combined with prompt surgical decompression of the neurovascular compressive elements in the thoracic outlet reduced morbidity and the necessity for thrombectomy with substantially improved clinical results, including the ability to return to work.45,46 This technique involves hospitalizing the patient, and through an antecubital indwelling catheter, a venogram is performed and thrombolytic therapy initiated. After lysis of the clot, prompt first rib resection with removal of compressive elements is performed.47
Clinical manifestations of “effort” thrombosis of the axillary–subclavian vein in the acute and subacute phases were evaluated in 660 extremities of 638 patients, 22 being bilateral. There were 312 females and 326 males, ranging in age from 16 to 52 years, with a mean of 33 years. Four hundred and sixty-two patients had unusual occupations that involved excessive, repetitive muscular activity of the shoulder, arm, and hand. Potentially aggravating occupations included such sports as golf, tennis, baseball, football, weight lifting, cheerleading, and drill team members, or other pursuits such as painters, beauticians, and linotype operators. The symptoms were usually exacerbated by working overhead, cold temperatures, or having the arm hang down for long periods of time.
Compression of the sympathetic nerves in the thoracic outlet may occur alone or in combination with peripheral nerve and blood vessels. The sympathetics are intimately attached to the artery as well as the bone. They may be compressed or “irritated” in primary or recurrent TOS situations.
As a cause of atypical chest pain – or pseudoangina – cardiac pain is simulated. Many arterial compressions result in more severe symptoms because of the additive or synergistic sympathetic stimulation. Trauma frequently is associated with the SMPS or reflex sympathetic dystrophy.
For uncomplicated, nontraumatic TOS symptoms, first rib resection alone with neurovascular decompression relieves the sympathetic symptoms without requiring dorsal sympathectomy.
However, if trauma is significant in the etiology, or if causalgia or SMPS is present, concomitant dorsal sympathectomy is routinely required to ameliorate the symptoms. Also, where surgery is required for recurrent TOS symptoms, the relief of accompanying causalgia usually requires dorsal sympathectomy. Initially, dorsal sympathectomies were performed at an interval after traumatic or recurrent TOS operations. However, because of the high necessity index and the inconvenience of a second operation, dorsal sympathectomy is now combined routinely with the initial TOS operative procedure for either trauma or reoperated recurrence patients.48,49
Major indications for dorsal sympathectomy include hyperhidrosis, Raynaud phenomenon, Raynaud disease, causalgia, SMPS or reflex sympathetic dystrophy, and vascular insufficiency of the upper extremity (see Chapters 144 and 146). Except for hyperhidrosis, most indications for sympathectomy require the usual diagnostic techniques, including cervical sympathetic block, to assess the relief of symptoms with temporary sympathetic blockade. When Raynaud phenomenon of a minor to moderate degree is associated with TOS, the simple removal of the first rib along with a cervical rib (if present) and stripping of the axillary–subclavian artery (neurectomy) generally relieves most symptoms after the initial operation.50 It is rarely necessary to perform a sympathectomy unless the Raynaud phenomenon is very severe, in which case a dorsal sympathectomy is carried out with first rib resection (Chapter 144). The only contraindication to dorsal sympathectomy is venous obstruction, that is, Paget–Schroetter syndrome (Chapter 145).
Surgical Approaches for Dorsal Sympathectomy
Historically, the anterior cervical approach to the cervical sympathetic chain has been used.51 The stellate ganglion lies on the transverse process of C6, and this approach is used by neurosurgeons and vascular surgeons. For hypertension, Urschel and Razzuk52 popularized the posterior approach with a longitudinal paraspinal incision with the patient in the prone position. Small pieces of the second ribs are removed, and the sympathetic chain is identified in the usual position. This approach has the advantage of allowing bilateral procedures at the same time without changing the patient's surgical position. The most common current approach is the transaxillary, transthoracic approach, which is performed through the second interspace with a transverse subhairline incision.53 This is more painful than the other approaches, but with video-assisted thoracoscopy, it can be performed with minimal discomfort.49
The approach used most frequently for TOS is the transaxillary approach for first rib resection and a dorsal sympathectomy.48,54 This has the advantage of minimal pain and combines two procedures with low morbidity. Video assistance is also used frequently with this approach.
Dorsal sympathectomy has been performed in 3214 extremities at our institution; 2974 of these were associated with neurologic TOS, causalgia, and SMPS. Two-hundred and forty operations were associated with arterial complications of TOS. In the neurologic TOS patients, 1721 dorsal sympathectomies were related to recurrent disease and reoperation.
On average, symptoms recur in 3 years (range 6 months to 25 years). In 46 patients, symptoms of sympathetic activity were apparent in fewer than 6 months. This is most likely from “sprouting,” or failure to strip the artery of its sympathetic nerves. This complication seems to occur less if the bed of the sympathetic chain is cauterized after dorsal sympathectomy. It also can be explained by high circulating concentrations of catecholamines.
The postsympathetic syndrome was observed in 39 patient extremities. This complication involves excessive postoperative pain (lasting as long as 6 months) in several nerve root distributions of the involved extremity and may be the result of injury to the somatic nerve. Unexpected Horner syndrome was noted in 27 patients; in 21 patients, the syndrome was only transient and resolved gradually.