Stenting of the left common illiac vein of patients with May-Thurner syndrome provided good short-term results as compared with nonstenting, according to the results of a retrospective, single-center registry study.

When to treat patients with May-Thurner syndrome (MTS) who have mild symptoms and what degree of compression should trigger intervention are in considerable question. Approximately 50% of the general population has some degree of left common illiac vein (LCIV) compression as detected using intravascular ultrasound (IVUS) and axial imaging, according to Johnathon C. Rollo, MD , of the University of Washington, Seattle, and his colleagues at the University of California, Los Angeles. They performed their study in order to address the debate over what were the optimal IVUS and venography criteria for stent implantation in these patients.

Of 102 patients in a registry, 63 had clear evidence of LCIV compression by the overlying right common iliac artery by IVUS assessment or venography. Nonthrombotic MTS patients who presented with chronic leg swelling or venous claudication underwent duplex ultrasound to rule out deep-vein thrombosis (DVT) were placed in compression therapy, and venography was performed to asses for iliac vein involvement

Iliac vein stenting was offered to those patients who met the following criteria:

• Sufficiently severe symptoms of swelling, venous claudication, or pain to affect their quality of life despite compression therapy.

• Diagnostic venogram imaging showing evidence of physiologically significant MTS compression, including contrast stagnation within the proximal left common and external iliac vein, contralateral cross-filling to the right iliac venous • circulation via hypogastric collateral networks, and/or significant retroperitoneal collateralization.

• IVUS assessment demonstrating greater than 50% luminal narrowing of the LCIV or extensive intravascular webs.

Patients who did not meet one of these criteria (generally the venogram findings) were treated with continued conservative management, which consisted of compression therapy, weight loss and exercise programs, and other conservative measures ( J Vasc Surg: Venous Lymphatic Disorders. 2017;5:667-76 ).

Of the 63 patients in the final study group, a total of 44 were treated with iliofemoral stents, with or without thrombolysis, and 19 conservatively managed patients who were not treated with stents served as controls. The mean age of the patients was 46 years, and 76% of them were women. With regard to comorbidities, 63% had a patient-reported history of DVT, and 22% had a patient-reported history of pulmonary embolism. Of the 63 patients, 32 had nonthrombotic MTS.

Stent diameter was based on IVUS measurement, with the goal of achieving normal vein diameter, and undersizing was avoided. Stenting was performed under local anesthesia.

A total of 44 patients (70%) underwent primary stenting (70%) or thrombolysis and stenting (30%), whereas 19 patients were not stented. Of these latter, 14 were nonthrombotic and were treated conservatively with compression therapy alone; the remaining 5 patients with thrombotic MTS were treated with lysis or angioplasty alone. Technical success was achieved in 100% of patients who had an intervention.

Primary and secondary patency rates in the stented thrombotic population were 87% and 93% at 24 months, respectively, by Kaplan-Meier analysis and were not significantly different from the results of the nonthrombotic stented patients.

Clinical improvement was significantly more likely in stented patients, compared with those managed without stenting (95% vs. 58%, respectively; P less than .001), Complete clinical resolution, defined as an absence of swelling or any other venous symptoms, was three times more likely in stented patients than in nonstented patients (64% vs. 21%, respectively; P less than .001), according to the researchers.

“MTS patients are typically young and relatively healthy. Whereas several series have demonstrated good intermediate-term results out to 7-10 years, the durability of these stents 20-30 years or more after implantation is unknown. For this reason, our group has been conservative in offering stent implantation to nonthrombotic patients,” Dr. Rollo and his colleagues stated.

“Regardless of the differential in clinical outcomes between stented and nonstented patients, this selective approach to stenting is reasonable in that those believed to be best managed with conservative therapy can be re-evaluated at regular intervals for clinical deterioration,” they concluded.

The authors reported that they had no disclosures.