Arterial Thrombectomy

In the past three years, Dr. Ushinksy has focused on building up peripheral vasculature service lines at the Mallinckrodt Institute of Radiology at Washington University in St. Louis. He has acquired skills not only in treatment of ALI, but also in building referral bases and collaborating with vascular surgeons and cardiologists. To begin, we review important aspects of a focused history and physical exam. It is crucial to assess whether the patient has underlying peripheral arterial disease (PAD), other thromboembolic diseases, or underlying coagulopathies. Different etiologies of thrombus could require additional consultation with hematologists and cardiologists. Additionally, timing of symptom onset is important to consider when planning interventions in an on-call setting. Dr. Ushinsky relies on extremity pulse exams using bedside doppler and the Rutherford Classification System for ALI to ascertain whether intervention can be helpful. In cases of Rutherford class 1-2a, intervention is usually warranted. Cases that fall into class 2b may or may not require intervention, and cases in class 3 and beyond usually do not gain benefit from intervention since lower extremity paralysis and clot burden is so severe.

With regards to types of interventions, Dr. Ushinsky highlights two common IR procedures– lysis catheter placement and endovascular thrombectomy. In the past, lysis catheters were the only available endovascular treatment. We walk through catheter placement, noting that in order to gain maximum benefit, the catheter should be placed across the entirety of the thrombus, with holes proximal and distal to the lesion, so that tPA can be infused throughout the clot and have appropriate inflow and outflow tracts. Good candidates for lysis catheter placement include patients who have extensive clot burden in small vessels and those who have underlying CLI that can be definitively addressed in a later procedure. A major difference between lytic catheter placement and thrombectomy is that patients receiving lytic therapy require admission to the ICU for close monitoring and frequent neurovascular checks.

Next, we pivot to discussion about newer thrombectomy devices. Dr. Ushinsky describes pros and cons of common devices that are used in his practice and types of cases that would benefit from each one. Thrombectomy is useful if there is a low clot burden that can be addressed in a single session. Additionally, this procedure is more appropriate than lysis catheter placement if the patient is elderly, has had recent surgery, or is otherwise a poor candidate for systemic tPA. Dr. Ushinsky always performs a diagnostic angiogram at the beginning of the case and a completion angiogram to confirm that the lesion has been fully treated. Overall, he believes that the best intervention for a patient is the one that the practitioner feels the most adept at and can safely perform.