Endovascular Treatment of DVT

REFERRAL PATTERNS
• Difficulty is getting the right patient to the right physician at the right time
• ER, urgent care, inpatient – all potential referral sources
• Helpful to have algorithm integrated into EMR – important to triage appropriately and risk stratify patients appropriate for discharge, patients appropriate for admission, patients appropriate for early intervention

CLINICAL EVALUATION
• Clinical presentation can vary widely
• Pick a method to help you and colleagues standardize your own practice
• Dr. Abramowitz uses Villalta score: https://www.mdcalc.com/villalta-score-post-thrombotic-syndrome-pts
• Also mentions Venous Clinical Severity Score (VCSS)
• Dr. Dexter comments on ER patients specifically
• True bleeding assessment – will patient tolerate anticoagulation
• Mobility is critical – how mobile will they be after procedure
• Why did DVT develop?: prior DVT, family history of clot, surgical interventions which may interrupt venous system (anterior exposure for lumbar spinal surgery, pelvic lymph node dissection)

IMAGING
• Extent of thrombus is important
• Duplex ultrasound good starting point
• Patients at higher risk for proximal DVT: cross-sectional imaging

IDEAL PATIENT THAT BENEFITS FROM DVT TREATMENT
• Young, healthy, hypercoagulable, first episode of DVT, mobile, compliant!

ACCESS
• Concept: expose as much of clot to therapy as possible
• Popliteal or small saphenous vein
• Posterior tibial (PT): internal jugular and popliteal good for mechanical thrombectomy devices; PT can be good for catheter directed thrombolysis

IVUS
• Both Dr. Dexter and Dr. Abramowitz use IVUS 100% of time
• Clot morphology
• External compression
• Venous wall scarring

DEVICES FOR DIFFERENT PATIENTS AND SCENARIOS
• Time frame of clot is important
• Size device to vessel being treated
• Patient consideration and possible contraindication to certain devices or treatments

ENDPOINTS
• Remove as much clot as possible
• Dr. Abramowitz: ideally <5% of clot
• Dr. Dexter: ideally completely clean
• What to do after maximal effort and clot remains
• Consider catheter lysis and return next day
• Anticoagulation, anticoagulation, anticoagulation

AFTERCARE
• Sequential compression devices (SCDs) - SCDs are critical peri-op and post-op
• Will typically continue the anticoagulant patient was on preop
• Lovenox for anticoagulation failures

ATTRACT TRIAL: https://www.nejm.org/doi/full/10.1056/NEJMoa1615066