Non-Operative Management of Paget-Schroetter Syndrome: A Single-Center Experience

Abstract: Objective. The preponderance of existing literature for the treatment of Paget-Schroetter syndrome (PSS) advocates clot lysis followed by thoracic outlet decompression (TOD). We postulate that long-term anticoagulation has equal outcomes to more invasive and costly surgical intervention, and review our experience with non-operative management of PSS. Methods. A retrospective review was conducted, examining patients between 1994-2014. Forty patients were identified with PSS, and 27 of these patients had sufficient follow-up for this analysis. Charts were reviewed for details of clinical presentation, disease course, interventions, duration of oral anticoagulation, ultrasound reports, and symptoms at long-term follow-up. Results. With a mean follow-up of 54.3 months, 23/27 patients (85%) were asymptomatic after non-operative therapy. In this cohort, 16/27 patients (59%) underwent catheter-directed thrombolysis. Average treatment course with oral anticoagulation was 8.6 months. Four patients (15%) remained symptomatic at follow-up. Two patients (7%) underwent thoracic outlet decompression at another institution, with good results. At least partial recanalization of vessels was documented in 25/27 patients (93%), although recanalization did not correlate with symptoms at long-term follow-up. Conclusions. Based upon equivalent functional results, non-operative management appears to offer similar outcomes for some patients with PSS. We propose a patient-tailored approach to the treatment of PSS, in which patients presenting acutely undergo catheter-directed thrombolysis, followed by a 6-12 month course of oral anticoagulation. Persistent symptoms, recurrent disease, lengthy duration of symptoms prior to diagnosis, and identifiable structural abnormalities may be factors predictive of poor outcomes after non-operative intervention.

J INVASIVE CARDIOL 2015;27(9):423-428

Key words: anticoagulation, Paget-Schroetter syndrome, non-operative intervention, deep vein thrombosis, upper-extremity DVT

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Effort thrombosis, more commonly known as Paget-Schroetter syndrome (PSS), defines the clinical condition of primary axillo-subclavian vein (ASV) thrombosis. The first case, described in 1875 by Sir James Paget, documented a patient suffering from “gouty phlebitis.”¹ Soon after, von Schroetter theorized that the occurrence of spontaneous thrombosis was directly related to physical stretch and strain of the upper-extremity muscles.² Over the subsequent decades, this clinical entity became increasingly recognized, and in 1948 Hughes coined the eponymous Paget-von Schroetter syndrome.³

The documented incidence of PSS has generally ranged from 1-2 cases per 100,000 annually.⁴ PSS accounts for approximately 15% of cases of upper-extremity deep venous thrombosis (DVT); in contrast, the vast majority of cases are non-spontaneous thromboses, related to upper-extremity instrumentation and catheterization.⁵ 

PSS is a subset of thoracic outlet syndrome (TOS), involving structures of the thoracic outlet causing compression of the ASV system leading to scarring and fibrosis, which in turn cause stasis, thrombosis, and damage to the veins.⁶ The vast majority of patients with TOS (over 95% of cases) are plagued by neurological deficits, while the remainder suffer from arterial (1%) or venous (3%) complications; this latter subset pertains to those with PSS.⁷ Repetitive motions of the upper extremity, especially hyperabduction and extension seen in swimming and baseball, are thought to exacerbate underlying thoracic outlet compression. Intrinsic factors also play a role in the pathogenesis of PSS; it has been shown that patients with hypercoagulable disorders have a higher incidence of spontaneous upper-extremity DVT.^8-10

The natural course of PSS is thought to involve a component of external compression on the ASV system, often attributed to a cervical rib, hypertrophied anterior scalene muscle, or the lateral insertion of the costo-clavicular ligament, compounded upon by repetitive motions that constrict the thoracic outlet. Interestingly, many of these patients do not have structural abnormalities, and for some individuals an underlying thrombotic disorder may be the inciting factor.¹¹ In either case, the result is perivenular or endothelial inflammation, leading to fibrosis and adhesions of the ASV system. This in turn can lead to intimal hyperplasia and thrombosis, resulting in intermittent venous outflow obstruction. Ultimately, patients present with acute venous obstruction, which causes upper-extremity pain, swelling, and discoloration.

The management of PSS has evolved over the last century and broad consensus has not yet been reached on many aspects of the treatment algorithm. Historically, patients were treated with arm elevation and oral anticoagulation, although unacceptable outcomes prompted surgeons to seek alternative interventions.^12,13 In the 1980s, catheter-directed thrombolysis was recognized to benefit patients with ASV thrombosis as it specifically addressed clot burden and allowed the reconstitution of venous flow.^14,15 In the early 1990s, the addition of thoracic outlet decompression (TOD), by means of first-rib resection and release of the anterior scalene muscle, to thrombolytic therapy was championed by Machleder.¹⁶ Modifications to the first-rib resection technique have been made over the years.^17,18

Currently, the preponderance of literature advocates for clot lysis followed by TOD as the mainstay of treatment.¹⁹ While operative intervention undoubtedly alleviates the underlying problem in certain patients, surgery for this condition is not without consequences. Complication rates for TOD have been estimated at 13%-20%, even up to 38% in one series.^20,21 While some complications convey minimal long-term morbidity, such as pneumothorax, pleural effusion, and clinically insignificant hematomas, more serious adverse events such as major bleeding and brachial plexus injuries do occur. 

This article reviews our experience in treating PSS patients non-operatively.

Methods

Ethical approval statement. This retrospective study design was reviewed and accepted by our Institutional Review Board.

Study design. A review of charts was performed, analyzing patients treated between 1994-2014. Inclusion criteria involved an ultrasound diagnosis of upper-extremity DVT. Exclusion criteria included a history of percutaneous or surgical intervention on the upper extremity and lack of at least one follow-up visit. 

Patients deemed appropriate for analysis had their charts reviewed for subjective and objective parameters. Objective data included age, laterality of the affected extremity, history of a similar event, date of symptom onset, date of presentation and diagnosis, thrombolytic therapy, duration of oral anticoagulation therapy if given, and the time to latest follow-up. Subjective measures included whether patients noted inciting factors prior to symptom onset and whether patients were found to be symptomatic or asymptomatic at their latest follow-up visit.

Objective data were recorded from reviewing inpatient notes, outpatient follow-up visits, documented phone call follow-up, procedure reports, and official imaging results. Subjective data were recorded from inpatient and office notes. In determining whether patients were or were not symptomatic, the physician inquired whether the patient was having problems with their affected arm, including any limitation in their ability to perform daily activities or exercise, and complaints of discoloration, swelling, or discomfort.

Results

Forty-seven patients were found to have upper-extremity DVT with a potential diagnosis of PSS. After further investigation, 7 individuals were excluded due to a previous upper-extremity intervention. Of the 40 patients who remained, 13 patients did not have a follow-up visit, and therefore their clinical course could not be studied. The remaining 27 individuals were included in this analysis (Table 1).

The average time of latest follow-up was 54.3 months (median, 42 months; range, 2-219 months). Our cohort included 12 males and 15 females. The average age at diagnosis was 40 years (median, 39 years; range, 24-71 years). The average number of days from symptom onset to diagnosis was 15 days (median, 5 days; range, 1-210 days). Ten patients (37%) recalled an inciting event that they believed to be the cause of their symptoms. These events included a period of vigorous exercise or activity (n = 7), sleeping with the ipsilateral arm above their head (n = 2), and carrying heavy equipment (n = 1).

Three patients (11%) presented with recurrent disease, all suffering from ipsilateral upper-extremity ASV thrombosis greater than 1 year prior to presentation at our institution. All 3 patients were found to have hypercoagulable disorders, including factor-V Leiden mutation (n = 1) and hyperhomocysteinemia (n = 2). These patients were followed and treated with 6 months, 6 months, and 7 months of oral anticoagulation, respectively. Despite presenting to us with recurrent disease, all 3 patients remained asymptomatic at their latest follow-up appointments at 22 months, 43 months, and 117 months following presentation, respectively. 

In this cohort, 16 of 27 patients (59%) underwent catheter-directed thrombolytic therapy and 11 patients (41%) did not (Table 2). No patients in this group underwent TOD. The 16 patients who underwent thrombolysis presented at an average of 3.75 days (median, 2.0 days). Only 1 of 16 patients (6%) remained symptomatic at long-term follow-up. The 11 patients who did not receive thrombolysis presented at an average of 31.5 days (median, 14.0 days) after symptom onset. In this group, 3 of 11 patients (27%) remained symptomatic at long-term follow-up.

With the exception of 1 patient (4%) who presented 210 days after symptom onset, all patients were treated with oral anticoagulation therapy. All 23 patients (100%) were prescribed oral anticoagulation therapy for an average duration of 8.6 months (median, 6 months; range, 0-54 months). At the latest time of follow-up, 25 of 27 patients (93%) has at least partial recanalization of their ASV system, as described on their official upper-extremity venous ultrasound reports.

Asymptomatic patients. After an average follow-up of 54.4 months (median, 42 months; range, 2-219 months), 23 of 27 patients (85%) were asymptomatic. In this subset, the average age at diagnosis was 42 years (median, 42 years; range, 24-71 years), with 10 males and 13 females. The average number of days from symptom onset to diagnosis was 5.7 days (median, 2 days; range, 1-21 days). 

Fifteen of 23 patients (65%) underwent thrombolytic therapy. All 23 patients underwent a course of oral anticoagulation therapy for an average duration of 9.2 months (median, 7 months; range, 2-54 months). At latest follow-up, 21 of 23 patients (91%) had at least partial recanalization of their ASV system on ultrasound.

Symptomatic patients. After an average long-term follow-up of 53.3 months (median, 45 months; range, 2-121 months), 4 of 27 patients (15%) were symptomatic. The average age at diagnosis was 29 years (median, 29 years; range, 24-34 years), with 2 males and 2 females. The average time from symptom onset to diagnosis was 69 days (median, 32 days; range, 1-210 days). Specifically, these patients presented at 1, 24, 40, and 210 days. 

Only 1 of 4 patients (25%) underwent thrombolytic therapy; this patient presented 1 day after symptom onset. The remaining 3 patients were not offered thrombolytic therapy. Three of 4 patients (75%) were prescribed oral anticoagulation therapy. One patient received 6 months of oral anticoagulation, while the other 2 patients sought TOD surgery shortly after diagnosis and therefore had a truncated course of oral anticoagulation. The patient who presented at 210 days was not treated with oral anticoagulation. All 4 patients (100%) had recanalization of their ASV system on ultrasound at latest time of follow-up.

As previously mentioned, 2 patients (50%) remained symptomatic after thrombolysis and actively sought TOD surgery at other institutions within a few weeks of their initial diagnosis. Both cited persistent symptoms of swelling and discomfort as their reasons for seeking out intervention. We thus classified these 2 patients as the “symptomatic at follow-up” subset. Both stated that their symptoms resolved after undergoing TOD and they have remained symptom free since surgery.

Discussion

Despite being a relatively rare phenomenon, PSS has been subject to a fair amount of review. The prominence of this vascular entity in the literature is likely due to its readily definable presentation, as well as its proclivity to affect those who are generally healthy and able bodied. In as much as it afflicts those who are otherwise able to have productive lives, it is essential to define effective interventions that simultaneously prevent unnecessary morbidity.

The most popular approach to treating PSS at this time is catheter-directed thrombolysis, with or without balloon angioplasty, if presentation is within 14 days of symptom onset. An interim course of oral anticoagulation with a goal international normalized ratio of 2-3 is prescribed, followed shortly thereafter by TOD.^22-24 Stenting of the ASV system has largely been abandoned due to high rates of recurrent thrombosis.

It appears that TOD may be the most effective treatment for patients presenting at a young age who are involved in professional sports and have persistent symptoms.²⁵ We believe, however, that it is necessary to question the necessity of TOD as a broad treatment strategy. There is a noteworthy proportion of patients affected who have acceptable outcomes without undergoing surgery. The key is to differentiate those who would benefit from TOD from those who would not. In our experience, clot lysis followed by oral anticoagulation and observation allows many patients to have acceptable functional outcomes with durable results.

Other factors may contribute to the pathogenesis of PSS. These factors may include older age, hypercoagulable disorders, and toxic habits. In a recent review from 2012, one group described older age (mean age, 45 years vs 38 years; P=.01), active smoking (33% vs 13%; P=.03), and longer symptom duration (90 months vs 48 months; P=.01) as risk factors for unresolved symptoms even after TOD.²⁶ Interestingly, while PSS is classically described as a disease of young, healthy individuals, almost one-half of our cohort (48%) consisted of patients >40 years old. 

Another review described that individuals with PSS who had an obvious structural abnormality of the thoracic outlet displayed relatively low rates of underlying hypercoagulable disorders.²⁷ That cohort was then compared with a group of patients who lacked obvious anatomic defects; the latter group displayed a comparatively higher proportion of hypercoagulable disorders. These data infer that the etiology of PSS is indeed multifactorial; structural abnormalities and intrinsic disorders of coagulation compounded by environmental factors can all contribute to the pathogenesis of this disease. In some cases, one or the other may be the primary inciting influence leading to thrombosis. In this regard, TOD may not be required in patients where a structural abnormality is lacking or not the primary causative factor.

When analyzing the 4 patients in our cohort who suffered from persistent symptoms, it was not surprising that 3 of these patients (75%) presented quite late after symptom onset, at 24, 40, and 210 months, respectively. Echoing the results of other reviews, we found that patients who presented in a subacute or chronic fashion were more likely to remain symptomatic in the long term, likely due to continued insult and remodeling of the affected vein (Table 2).^25,28 

These data demonstrate that alleviating the clot burden in the ASV system via thrombolysis is of paramount importance and underlies the need for expedient diagnosis and urgent referral.^29,30 Unfortunately, once a clot has become chronic, generally after a period of approximately 14 days, the success rate of catheter-directed lysis decreases. In these situations, TOD may be the most appropriate intervention.

One review in 2007 documented 34 patients with ASV thrombosis, including 8 patients who presented after months to years of symptoms and 12 patients who presented >14 days after symptom onset.³¹ The 8 patients who presented with chronic disease and 8 of the 12 patients who presented in subacute fashion (>14 days) proceeded directly to TOD via transaxillary first-rib resection. This review did not discuss the subjective outcomes of their patients with regard to pain and upper-extremity function, although they reported primary and secondary patency rates of 83% and 83% following TOD alone. It would appear that when thrombolysis is not a viable option due to delayed presentation, TOD – potentially with venous reconstruction – may be the most appropriate treatment option.

Interestingly, although thrombolysis appears to impart a major long-term benefit on patients with PSS, whether or not they undergo TOD, one study demonstrated this therapy to be somewhat superfluous if TOD was ultimately to be performed. Guzzo and colleagues reviewed a cohort of patients who underwent a total of 110 first-rib resection and scalenectomy procedures, 45 of whom underwent preoperative thrombolysis and 65 of whom had only preoperative oral anticoagulation.²⁸ Both groups had equivalent positive long-term functional outcomes, calling into question the necessity of thrombolysis if TOD is ultimately employed. It would appear that some patients undergoing TOD may not require preoperative thrombolysis, and given our experience, the same appears to hold true for the opposite; some patients who undergo thrombolysis may not require TOD.

Another area of debate is in the recommendation for postthrombolysis or postoperative oral anticoagulation. No good studies have been performed to determine if and for how long anticoagulation is required. Most authors appear to use a 3-6 month treatment regimen of oral anticoagulation. We use a 6-12 month treatment protocol of anticoagulation, with an average in our review of 8.6 months (median, 6.0 months).

A cohort that deserves specific mention is those with PSS who have concurrent prothrombotic conditions that may explain their propensity to develop upper-extremity thrombosis.^8,27 Three patients presented to us with recurrent disease, all of whom were found to have hypercoagulable disorders. Patients with thrombophilia who present with PSS deserve special attention and may require long term or even lifelong anticoagulation to prevent recurrent thrombosis.¹⁰ 

Patients who have an inherent hypercoagulable state and develop PSS may or may not benefit from TOD. It is unclear whether these patients develop ASV thrombosis primarily because of external, mechanical impingement or rather from the propensity to clot coupled with turbulent flow resulting from repetitive hyperabduction and extension of the upper extremity. In other words, in patients with a prothrombotic state, their main issue may be a natural propensity to clot, exacerbated by some form of upper-extremity exertion or thoracic outlet anomaly.¹⁰ It would be interesting to review patients with positive hypercoagulable disorders and PSS and follow how they have fared with non-operative management specifically.

Study limitations. This retrospective study was performed on a small cohort of patients, and is first and foremost limited insofar as variables were not prospectively controlled. Furthermore, retrospective reviews preclude standardization of questions asked of patients at the time of their presentation and treatment. Of all those recognized to have upper-extremity DVT, we identified 13 patients who were unable to be analyzed in this study due to lack of sufficient follow-up. Their inclusion in this study may have provided further clarification on the results of non-operative management of PSS.

Questions asked of patients regarding the evaluation of their disease and symptoms were documented from their subjective responses. A validated outcome measure was not used, although this would be favorable in a prospective study. The DASH survey would allow standardization of questions and responses and would be an appropriate tool to evaluate subjective responses of patients with PSS.^32,33 

Ultrasound diagnosis of upper-extremity DVT is relatively straightforward; however, following the progression or resolution of clot on ultrasound requires interpretation by an ultrasound technician, which could be argued to be somewhat subjective. At our institution, all patients underwent Doppler ultrasound with the same three vascular technicians, who were stably employed over the duration of the study; the technicians had no awareness of this review and thus were not biased when making their evaluations.

Conclusions

Even with relatively uncommon conditions such as PSS, we strive to treat our patients with the most effective therapies while limiting complications and resultant morbidity. A patient-tailored approach to managing patients with PSS appears most appropriate. Available studies have reiterated support for urgent management of acute thrombosis with catheter-directed thrombolysis if the patient presents within 1-14 days of symptom onset. Beyond this time frame, thrombolysis can be attempted, although it is usually unsuccessful. Most then advocate for a period of oral anticoagulation ranging between 3-6 months. 

Given our experience and the experiences described by our colleagues, our current management algorithm for PSS would involve thrombolysis with or without percutaneous venoplasty if the patient presents within 14 days of symptom onset, followed by 6-12 months of oral anticoagulation. Serial ultrasounds would be performed at 1 week and at 3, 6, and 12 months thereafter. It should be noted that in the absence of symptoms, ultrasound documentation of the ASV system does not change management and its utility is primarily academic. If patients are symptom free at follow-up, they would complete a 6-12 month course of oral anticoagulation. 

It is at this juncture that we would recommend selective TOD therapy with paraclavicular first-rib resection and anterior scalenectomy. Given our findings, patients presenting after 14 days of symptom onset should be considered for TOD, potentially with venoplasty. Similarly, any patient being managed conservatively who presents with persistent symptoms at follow-up should be considered for TOD.

The experience gained with our management of patients with PSS indicates that there may be a subset of patients who have favorable outcomes with thrombolysis and oral anticoagulation. It appears that different PSS patient subsets may in fact benefit best from different treatment algorithms. Ultimately, while prospective, randomized controlled trials would be provocative, they are unfortunately impractical in such a rare disease.

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From the Division of Vascular Surgery, Mt. Sinai St. Luke’s-Roosevelt Hospital Center, New York, New York.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.

Manuscript submitted November 17, 2014 and accepted January 26, 2015.

Address for correspondence: John C. Lantis II, Dept of Vascular Surgery, St. Luke’s-Roosevelt Hospital Center, 1090 Amsterdam Avenue, Suite 7A, New York, NY 10025. Email:  jlantis@chpnet.org