Catheter directed thrombolysis for deep vein thrombosis in 2022: Rationale, evidence base and future directions.

INTRODUCTION: Catheter directed thrombolysis (CDT) has evolved as a treatment modality for patients diagnosed with proximal and caval deep vein thrombosis (DVT) and has shown to be superior in certain subset of patient population despite conflicting evidence as seen in the large 4 randomized controlled trials. RATIONALE FOR CDT IN ACUTE DVT PATIENTS: DVT adversely affects the quality of life and adds significantly to the treatment and hospitalization costs. CDT and pharmaco-mechanical catheter directed thrombolysis (PCDT) has been shown to accelerate symptom resolution, decrease symptom severity and decrease recurrence rates with successful procedures in certain patients. RANDOMIZED CLINICAL TRIALS (RCTS): Four RCTs have evaluated the use of CDT and PCDT in acute proximal DVT patients suggesting clinical benefit compared to anticoagulation alone. These trials suggested using CDT for proximal DVT patients with a lower bleeding risk as CDT may decrease PTS. Successful CDT treatment showed improvement in moderate to severe symptoms of post thrombotic syndrome (PTS). However, these studies have limitations including the use of non-standard techniques, different equipment and different endpoints. FUTURE DIRECTIONS AND CONCLUSION: Our goal is to highlight the factors which can potentially improve CDT outcomes in proximal DVT patients. Based on studies, patients with proximal DVT and a low bleeding risk may benefit from early CDT by decreased symptom severity of PTS, however, improvement in procedural technique, equipment and procedural success rates is necessary. With appropriate patient selection, and objective endpoints, we can further establish the benefit of CDT and PCDT in acute DVT patients.