Endovascular Thrombolysis in Hypothenar Hammer Syndrome: A Systematic Review

Objectives: Hypothenar hammer syndrome (HHS) is a rare vascular disease caused by blunt trauma of the hypothenar region. The optimal therapeutic strategy remains debatably since no large comparative studies are available yet. We want to evaluate the effectiveness of intra-arterial thrombolysis on angiographic and clinical outcome parameters in patients with HHS by performing a systematic review of the existing literature. Methods: A literature search of PUBMED/MEDLINE and SCIENCE DIRECT databases was performed up to May 2021. Results: In total, 16 manuscripts with 43 patients were included in the systematic review. Intra-arterial thrombolysis led to angiographic improvement in 29 patients (67.4%) and to clinical improvement in 34 patients (79.1%). Deterioration of arterial perfusion or clinical symptoms after thrombolysis were absent. Post-interventional complications were reported in only one patient (2.3%) without any bleeding complication. Logistic regression analyses demonstrated that a combined administration of fibrinolytics and heparin was associated with a significantly improved arterial patency [OR 12.57 (95% CI 2.48-97.8), p = 0.005] without significant amelioration of clinical symptoms [OR 3.20 (95% CI 0.6-18.9), p = 0.172]. The use of rt-PA compared to other fibrinolytics and a prolonged thrombolysis duration of more than 24 h did not show statistically significant effects. Intra-arterial thrombolysis was significantly less effective in patients who had undergone thrombolysis with a delay of more than 30 days regarding clinical improvement [OR 0.07 (95% CI 0.00-0.54), p = 0.024]. Conclusions: Intra-arterial thrombolysis with a combination of fibrinolytics and heparin is an effective and safe therapeutic option in patients with acute HHS.