You are in: eMedicine Specialties > Thoracic Surgery > Vascular Subclavian Vein ThrombosisArticle Last Updated: Oct 5, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 11
  Author: Shabir Bhimji, MD, PhD, Locum Cardiothoracic and Vascular Surgeon, Saudi Arabia and Middle East Hospitals Shabir Bhimji is a member of the following medical societies: American Cancer Society, American College of Chest Physicians, American Lung Association, and Texas Medical Association Coauthor(s): Steven Ugbarugba, MD, Fellow, Assistant Clinical Instructor, Department of Medicine, Section of Gastroenterology, State University of New York at Brooklyn; Chike Magnus Nzerue, MD, Chief, Nephrology Unit, Harbin Clinic Editors: William H Pearce, MD, Chief, Division of Vascular Surgery, Violet and Charles Baldwin Professor of Vascular Surgery, Department of Surgery, Northwestern University School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Vincent Lopez Rowe, MD, Assistant Professor of Surgery, Department of Surgery, Division of Vascular Surgery, University of Southern California Medical Center; Paolo Zamboni, MD, Professor of Surgery, Chief of Day Surgery Unit, Chair of Vascular Diseases Center, University of Ferrara, Italy; Mary C Mancini, MD, PhD, Director of Cardiothoracic Transplantation, Professor, Department of Surgery, Louisiana State University Health Sciences Center Author and Editor Disclosure Synonyms and related keywords: effort-induced thrombosis, Paget-von Schrötter syndrome, Paget-von Schrotter syndrome, Paget-von-Schrotter syndrome, gouty phlebitis, subclavian vein thrombus, venous thrombosis, vascular thrombus, sports-related injury, sports injury, thrombolysis, paradoxical embolism, axillary subclavian deep vein thrombosis, ASDVT INTRODUCTIONSection 2 of 11
  Sir James Paget first described thrombosis of the subclavian veins in 1875. He coined the name gouty phlebitis to describe the spontaneous thrombosis of the veins draining the upper extremity. He observed that the syndrome was accompanied by pain and swelling of the affected extremity. However, he incorrectly attributed the syndrome to vasospasm. In 1884, von Schrötter postulated that this syndrome resulted from occlusive thrombosis of the subclavian and axillary veins. In recognition of the work of these pioneers, in 1949, Hughes coined the term Paget-von Schrötter syndrome. A related condition is thrombosis of the subclavian vein that is induced by the presence of indwelling catheters. The incidence of this condition has increased remarkably over the past two decades because of the extensive use of catheters in patients with cancer and other chronic medical conditions. History of the ProcedurePatients may describe a history of trauma or, more frequently, strenuous use of the arm (>50% of cases). Common precipitating activities involve repeated hyperabduction and external rotation of the arm or backward and downward rotation of the shoulder. Causative activities may include participating in cricket, tennis, wrestling, lifting weights, water polo, gymnastics, baseball, or chopping wood. Because the symptoms of subclavian stenosis are fairly dramatic, most patients present promptly to the emergency department, usually within 24 hours. They may report dull ache in the shoulder or axilla, and the pain often is worsened by activity. Conversely, rest and elevation often relieve the pain. Patients with catheter-associated axillary subclavian deep vein thrombosis (ASDVT) report similar symptoms of the ipsilateral arm or shoulder with the indwelling catheter. FrequencyPrior to 1967, thrombosis of the axillary or subclavian vein accounted for 1-2% of all cases of deep vein thrombosis. Since then, the incidence has risen due to the more frequent use of central venous access for multiple clinical conditions. Among patients with effort-induced thrombosis with subclavian vein stenosis, the thrombosis occurs in the dominant arm in 80% of cases. EtiologyThe primary etiology is referred to as effort-induced thrombosis or Paget-von Schrötter syndrome. It usually results from the excessive use of the involved arm by predisposed individuals. The secondary etiology is subclavian vein catheterization, especially in patients with cancer. Other causes include transvenous pacemakers, factor V Leiden mutation, protein C deficiency, protein S deficiency, antithrombin III deficiency, and prothrombin 20210A mutation. Long-term parenteral nutrition and use of hemodialysis catheters account for some cases of subclavian vein thrombosis. Trauma is only rarely associated with this syndrome. In a few cases, the diagnosis remains unknown. However, routine follow-up with these patients has revealed the development of lung cancer within 1 year of follow-up. The most common lung malignancy associated with subclavian thrombosis has been the Pancoast tumor. PathophysiologyDifferentiating catheter-associated subclavian vein thrombosis and Paget-von Schrötter syndrome is important because they appear to have different natural histories. Paget-von Schrötter syndrome It sometimes is referred to as spontaneous axilla-subclavian vein thrombosis to express the usually dramatic unexpected presentation of the disorder in otherwise healthy, generally young individuals. Over the past 2 decades, recognition has grown that the disorder can occur equally in both sexes and can affect all age groups. In the 1960s, the term effort-induced thrombosis was used to describe this disease to acknowledge that it often follows unusually strenuous use of the arm or shoulder on the affected side. The pathophysiology of effort-induced thrombosis is multifactorial. It involves compressive changes in the vessel wall, stasis of blood, and hypercoagulability. External compression of the axillary-subclavian vein has been suggested to contribute to the stasis of blood that engenders thrombosis. The factors that cause external compression include (1) anomalous subclavius or anterior scalene muscle, long transverse process of cervical spine, cervical rib, abnormal insertion of the first rib, congenital fibromuscular bands, or narrowing of the costoclavicular space from depression of the shoulder; (2) stress from exercise temporarily causing hypercoagulability; and (3) repetitive shoulder-arm motion causing microscopic intimal tears in the vessel wall. These factors, taken together, satisfy the classic Virchow triad for thrombosis. Furthermore, coexistent hematologic abnormalities that can contribute to thrombosis include protein C deficiency, antithrombin III deficiency, factor V Leiden mutation, andprothrombin 20210A mutation. Catheter-induced subclavian vein thrombosis Introducing catheters and transvenous pacemakers in to the subclavian vein alters the venous flow and increases turbulence. This results in platelet aggregation, release of procoagulants, and, ultimately, fibrin deposition. This causes a further reduction in the lumen of the vessel due to thrombus formation, which eventually culminates in total vessel occlusion. Intravenous medications and even parenteral nutrition have been known to cause thrombophlebitis. In patients with cancer, an additional contributing factor is that the tumor may generate procoagulant factors, predisposing to thrombosis at sites remote from the tumor. ClinicalNot all patients with subclavian vein thrombosis are symptomatic. Those with symptoms may present with mild-to-moderate nonpitting edema and mild cyanosis of the hands and fingers on the affected side. Dilatation of subcutaneous collateral veins may be present over the upper arm and chest. This later sign may be the only clue to ASDVT in otherwise asymptomatic patients with catheter-related venous thrombosis. In a few cases, in which the diagnosis was missed or delayed or the patient presented late, the thrombus may have extended to the superior vena cava. These patients show most features of the superior vena cava syndrome, including face and neck swelling, periorbital edema, blurred vision, and some degree of facial cyanosis. INDICATIONSSection 3 of 11
In patients with effort-induced vein thrombosis of less than 2 weeks duration, thrombolytic therapy is recommended. Chronic ASDVT does not respond to thrombolytics and is better treated either conservatively with warfarin, or by surgical bypass, if symptoms are severe. RELEVANT ANATOMYSection 4 of 11
The subclavian vein courses over the first rib and posterior to the clavicle. The artery lies superior and posterior to the vein. CONTRAINDICATIONSSection 5 of 11
Surgery is rarely indicated in ASDVT associated with central lines. Thrombolytic drug therapy is rarely recommended for patients who present with chronic subclavian vein thrombosis. WORKUPSection 6 of 11
Lab Studies
Imaging Studies
TREATMENTSection 7 of 11
Medical therapyThe initial treatment of subclavian vein thrombosis is conservative management, which includes rest, elevation of the limb, and application of heat or warm compresses. In a few patients who have minimal symptoms and no anatomical defects, physical therapy is always the first goal of therapy. Structured physical therapy may help the patient lose weight and loosens the adhesions at the site of obstruction. Physical therapy may also improve range of motion, decrease swelling, and help decrease pain. The different natural histories of Paget-von Schrötter syndrome and catheter-induced subclavian vein thrombosis indicate different treatment protocols. Because large series of patients with this condition are lacking, the therapeutic approach to subclavian vein thrombosis is mainly anecdotal. Heparin Unfractionated or low molecular weight heparin (LMWH) can maintain patency of the venous collaterals and reduce the chance of propagation of the thrombus. In all cases, heparin therapy is followed by warfarin therapy, with an international normalized ratio (INR) goal of 2-3. Heparin is usually the initial therapy, followed by warfarin. LMWH has been used for both inpatient and outpatient therapy. Most studies have shown that LMWH is just as effective as unfractionated heparin, but the former is associated with a significant decreased incidence of venous thromboembolism. Warfarin is continued for 6-9 months, and an INR of 2:3 is maintained. Patients who only receive inpatient heparin and are no longer on warfarin therapy are at risk of recurrence and long-term disability. Anticoagulation is required in all patients for a period of 6-9 months or longer, depending on the cause of the thoracic outlet syndrome. In some patients who also have hypercoagulable disorders, the treatment is lifelong. Paget-von Schrötter syndrome Currently, most investigators favor using thrombolytic therapy to rapidly restore patency of the vein. Thrombolytic therapy should be initiated within 5-7 days of venous thrombosis. Fortunately, this syndrome occurs in fairly young individuals who do not have multiple medical illnesses that may contraindicate thrombolytic therapy. Thrombolytic therapy is preferred over thrombectomy because it does not carry the risks of an operation and the possibility of an intimal tear related to the embolectomy catheter. In some cases, therapy may involve diagnostic venography, followed by thrombolysis, followed by several weeks of anticoagulation. If symptoms recur, a repeat venography may be indicated, possibly followed by balloon dilatation with or without stenting of the subclavian vein, and more anticoagulation. The desired International Normalized Ratio is 2-3. The goal of therapy is to minimize the likelihood of significant symptoms of venous obstruction. To perform catheter-directed thrombolysis, the catheter is embedded in the thrombus. Urokinase infusion is started with a loading dose of 250,000 IU, followed by 4000 IU for the first hour, and 1000 IU for the next 24 hours. Heparin is infused at a rate of 800 IU/h. Monitoring is performed by maintaining the fibrinogen level at least 80-100 mg/dL. If venous patency is assured, warfarin is maintained for 3-6 months. Recently, urokinase was indefinitely removed from the market, forcing interventional radiologists to adopt less clinically defined protocols using tissue-plasminogen activator (tPA). As the clinical situation with thrombolytic agents evolves and newer agents enter the market, flexibility in thrombolytic administration protocols will be paramount. Catheter-associated subclavian vein thrombosis Prophylaxis treatment in patients undergoing chemotherapy may include giving a fixed dose 1 mg of warfarin sodium (Coumadin) daily beginning on day 3 before catheter placement. This has been shown to lower the incidence of thrombosis. Exercise caution in selecting patients for thrombolytic therapy because patients with catheter-associated subclavian thrombosis often have significant comorbidity. Surgical therapyIndications for surgical treatment include (1) the presence of an anatomic anomaly such as anomalous subclavius or anterior scalene muscle, congenital fibromuscular bands, or narrowing of the costoclavicular space from depression of the shoulder; (2) rethrombosis of the vein after previous thrombolytic treatment; and (3) endoluminal stent placement to prevent stent fracture from compression against the first rib. Forms of surgical treatment can include (1) embolectomy, (2) bypass, (3) first rib resection via the axilla or supraclavicular approach, and (4) medial subtotal claviculectomy. Endovascular treatment With recent advances in endovascular therapy, angioplasty and stenting is an excellent way to maintain venous patency. Data and follow-up on this technique are limited. When the superior vena cava is also involved, current endovascular techniques allow for stenting of the vessel, which produces excellent results. Suction thrombectomy with an AngioJet System (Possis Medical, Inc., Minneapolis, Minn) is often used with thrombolysis when the thrombus is localized. The procedure can rapidly extract the thrombus and reduce both the dose and duration of thrombolytic therapy. Suction thrombectomy is most useful for patients who present early. Surgical thrombectomy is fast becoming the procedure of choice; it is a better alternative to simple anticoagulation. Preoperative detailsThe purpose of the preoperative evaluation is to determine if known or unsuspected coexisting disease should delay, modify, or preclude the operation. Obtain a history and physical examination to identify risk factors and warning signs of coexisting diseases. This information guides further direction and depth of study. Relevant laboratory tests include CBC count, serum electrolyte levels, urinalysis, chest radiograph, ECG, clotting profile, crossmatch, and a stool examination for blood. Consultations should include a general internal medicine physician and an anesthesiologist. Intraoperative detailsApproach a first rib resection by the transaxillary route (Roos et al) or the supraclavicular route. Typically, the transaxillary route is simpler, safer, and offers cosmetic benefits. The procedure is indicated below. Using the lateral thoracotomy position with the arm elevated, a skin incision is made in the axillary hairline between the pectoralis major and latissimus dorsi muscles. The first rib is reached by blunt dissection in the axillary tunnel, taking care to avoid the second intercostobrachial nerve. The subclavian artery and vein are identified, and the subclavius muscle tendon is divided. Then, the anterior scalene muscle is identified and divided at the point where it inserts onto the first rib, anterior to the artery. At this point, digitally search for anomalous bands. They may originate from the C-7 transverse process, from an incomplete cervical rib, or from the middle scalene muscle. After any bands are divided, the middle scalene muscle and the intercostal muscle attachments are pushed off the first rib. When all the muscle fibers are cleared and the T-1 nerve root is visualized and protected, the rib is divided and removed. The wound is irrigated with saline to detect pneumothorax. If present, it can be treated by inserting a small chest tube into the pleural space. The tube can be removed in the recovery room if the lung is fully expanded and no air leak is present. Postoperative detailsPain relief is one of the most important aspects of postoperative care. Various forms of narcotics can be administered parenterally or by patient-controlled analgesia devices. Adequate pain control cannot be over emphasized. Vital signs should be closely monitored as per unit protocol, then every 4 hours for 24 hours, and then every shift. In most cases, a Foley catheter is not required. Administer 5% dextrose in lactated Ringer solution at 125 mL/h, and keep the arm elevated. If the surgery is not complicated, routine postoperative laboratory tests are not required. Prothrombin time and activated partial thromboplastin time should be measured every 6 hours if heparin therapy is started. Early mobilization is important, and discharge planning should begin at admission. Patients usually are discharged when they are medically stable, afebrile, tolerant of oral intake, ambulatory, and reasonably comfortable with the ongoing rehabilitation exercises. Follow-upFollow up carefully with patients with subclavian vein thrombosis to ensure that the condition does not reoccur. Patients with persistent symptoms and evidence of recurrence may require radiological workup and, possibly, surgery. For excellent patient education resources, visit eMedicine's Circulatory Problems Center. Also, see eMedicine's patient education article Phlebitis. COMPLICATIONSSection 8 of 11
Pulmonary embolism may occur in as many as 20-36% of patients. Stroke may occur as a manifestation of paradoxical embolism in the presence of a patent foramen ovale. Other complications can include the following:
OUTCOME AND PROGNOSISSection 9 of 11
Case fatality rates for untreated ASDVT-related pulmonary embolism may be as high as 10%, which is similar to pulmonary embolism originating from the lower extremity. The long-term consequences of venous occlusion cause substantial morbidity related to persistent pain and swelling for protracted periods of time. These symptoms occasionally are severe and can be exacerbated by physical activity, particularly with extended use of the affected arm. Consequently, this syndrome can lead to occupational disability and can adversely impact the patient's quality of life. Conservative treatment consisting of bed rest, limb elevation, and anticoagulation is associated with a worse outcome. Recent reports suggest that as many as 74% of patients treated with these conservative measures have residual disability compared to those that are treated with thrombolysis. FUTURE AND CONTROVERSIESSection 10 of 11
Subclavian vein thrombosis is becoming a more common problem because of widespread use of central venous catheters for various medical conditions. The demand for a more standardized treatment is becoming greater than ever. However, until randomized data from well-designed trials are available, absolute statements about treatments cannot be made. However, linked medical records using administrative health care data sets may provide information (ie, re-admission or level of outpatient services) on the results of treatment of large numbers of patients with subclavian vein thrombosis or significant risk factors such as central venous cannulation. Until such information is obtained, the best treatment of subclavian vein thrombosis is to prevent it by limiting the use of central venous catheters for extended periods of time. REFERENCESSection 11 of 11
Subclavian Vein Thrombosis excerpt Article Last Updated: Oct 5, 2006 |
