931 - Complex Regional Pain Syndrome Secondary to Revascularization Procedure in a Patient with Chronic Deep Vein Thrombosis

A 79-year-old male with history of essential thrombocythemia and chronic deep vein thrombosis (DVT) presented to the emergency room with worsening right lower extremity (RLE) pain. Computed tomography angiography revealed severe occlusion of the right common iliac, popliteal, and peroneal arteries. Interventional radiology recommended percutaneous angioplasty and graft placement which resolved stenosis. The patient was started on dual antiplatelet therapy and was discharged home with improvement. On follow-up, patient persisted with pain limiting ambulation, yet with preserved strength and deep tendon reflexes, except for S1. The RLE was found with rubor, coldness, shedding, edema, allodynia, reduced sensation, and impaired proprioception. Electrodiagnostic test indicated RLE polyneuropathy and Bone scan revealed a diffuse hyperemic reaction in the RLE, consistent with active Complex Regional Pain Syndrome (CRPS). The patient was referred to physical therapy with optimized pain management, with significant clinical improvement. 

Discussions:

CRPS may develop after an amputation, stroke, injury or surgical intervention and is characterized by sensory, vasomotor, edema, and motor symptoms. In this case, despite patient having chronic DVT, he was mostly asymptomatic prior to the revascularization procedure. Rare cases have been reported identifying CRPS developing after similar surgical interventions, highlighting the potential for CRPS to arise after vascular procedures when pre-existing conditions like chronic DVT are present. Most cases of CRPS present within 1-3 months after inciting event, however in this patient worsening pain arose 10-15 days after initial procedure. CPRS treatment involves pharmacotherapy, physical therapy, sympathetic blockade and behavioral therapy.

Conclusions:

CRPS is a chronic pain syndrome with significant impact on quality of life. A high level of suspicion should be considered in patients with multiple risks factors, particularly those with chronic conditions or vascular interventions.  Early diagnosis using clinical criteria and imaging are vital for effective management, progression prevention and avoid delays in treatment.