Sildenafil as a Diagnostic Tool and Treatment Option for Popliteal Artery Entrapment Syndrome

Case Diagnosis: Popliteal artery entrapment syndrome

Case Description or Program Description: This case report describes a case of a 21-year-old female athlete presenting with progressive exertional bilateral calf pain during tennis matches recalcitrant to numerous treatment options.

Setting: Outpatient Clinic

Assessment/Results: A 21-year-old female tennis player experienced progressive exertional bilateral calf pain unresponsive to standard treatments. Empiric administration of sildenafil (20 mg) one hour before activity resulted in significant symptomatic relief, allowing several hours of pain-free tennis over a two-month period. A transient episode of light-headedness occurred during a delayed match, managed effectively with hydration. As symptoms recurred, increasing the sildenafil dose to 40 mg provided temporary relief, but efficacy diminished over time. A subsequent trial of vardenafil (5 mg) yielded similar partial relief. Diagnostic evaluations, including imaging studies, confirmed the diagnosis of Popliteal Artery Entrapment Syndrome (PAES). Surgical intervention was performed, leading to complete resolution of symptoms and the patient's return to competitive tennis without limitations

Discussion (relevance): PAES is an uncommon disorder that can be mistaken for other lower extremity pathologies, such as chronic exertional compartment syndrome (CECS). Diagnosis is challenging; studies using MRI have shown that healthy asymptomatic subjects can exhibit compression of the popliteal artery during plantarflexion, potentially leading to false-positive diagnoses. While angiography can confirm the diagnosis, it carries risks such as nephropathy, vascular injury, and hemorrhage. Sildenafil, a phosphodiesterase-5 (PDE5) inhibitor commonly used to treat erectile dysfunction, works by inhibiting PDE5, which breaks down cGMP, resulting in smooth muscle relaxation via decreased intracellular calcium.

Conclusions: This case highlights the potential transient effectiveness of sildenafil in managing PAES symptoms due to arterial compromise. Further research is warranted to explore both the diagnostic and therapeutic roles of sildenafil in PAES and its effectiveness in treating non-arterial pathologies such as CECS.