Underutilization of Thrombolytic Therapy for Patients Diagnosed with Acute Deep Venous Thrombosis in the Outpatient Setting.

Background: Catheter-directed thrombolysis (CDT) has been shown to be a safe and effective treatment for the management of acute iliofemoral deep venous thrombosis (DVT). The potential benefits of this therapy include more rapid resolution of symptoms and possible reduction in the long-term sequelae. Many patients diagnosed with DVT in the inpatient setting have contraindications to lytic therapy, but less is known regarding the suitability of thrombolysis for outpatients diagnosed with acute DVT. We sought to determine the proportion of patients who were candidates for thrombolytic therapy and referred to a vascular specialist for evaluation.

Methods: A manual search of an outpatient vascular laboratory associated with a tertiary medical center was performed to identify all patients referred for the purpose of ruling out DVT between January 2013 and December 2014. Vascular laboratory studies conducted for evaluation of venous insufficiency were excluded. The electronic medical records were reviewed to evaluate for contraindications for thrombolysis.

Results: Over a 2-year period, there were 689 referrals to the outpatient vascular laboratory for the evaluation of patients with suspected DVT. Of the 689 referrals, 47 (6.8%) were found to have acute DVT, and 66 (9%) were found to have chronic DVT. Of the 47 patients with acute DVT, 41 involved the lower extremities. Fifteen of the 41 patients (37%) with extensive acute iliofemoral DVT had no absolute or major contraindications for CDT. Of these 15 patients, only 33% were referred to a vascular specialist (4 to vascular surgery and 1 to IR). Two patients (13%) agreed to and underwent successful CDT.

Conclusions: Although the majority of patients with acute lower extremity DVT diagnosed in the outpatient vascular laboratory were not candidates for thrombolysis, one-third of those who may have benefited from CDT were referred to a vascular specialist to discuss lytic therapy. Given the potential benefits of CDT, it is imperative that patients with acute iliofemoral or extensive femoral DVT be offered an evaluation by a vascular specialist to optimize outcomes after this diagnosis.