Abstract
To the Editors:
Giannopoulos et al 1 report the utility of intravascular lithotripsy (IVL) for lesion modification in the treatment of calcified carotid artery lesions among 21 high-surgical-risk patients. We commend the authors for demonstrating the feasibility and safety of IVL for de novo as well as in-stent restenotic lesions. No adverse events were reported except in 1 patient who developed ischemic stroke 17 days after the index procedure that was attributed to the catheter manipulation in the aortic arch rather than to microemboli formed after IVL therapy. Embolic protection devices (EPD) were used in all cases. We wish to highlight a few points relevant to the discussion.
We recently demonstrated IVL-facilitated endovascular interventions of the aortic arch; 2 of the patients in our study underwent carotid interventions.2,3 One patient developed acute transient unilateral vision loss following IVL treatment in the internal carotid artery, despite the use of the distal EPD, Emboshield (Abbott Vascular, Santa Clara, CA, USA). This was felt to be secondary to IVL balloon withdrawal and release and subsequent downstream embolization of embolic debris to the ophthalmic artery. The patient was treated with nonselective delivery of tissue plasminogen activator at the ostium of the ophthalmic artery. At the completion of the procedure, the patient regained his vision. The patient was monitored in the intensive care unit and unfractionated heparin was administered for additional 48 hours. We wanted to highlight this important complication encountered during carotid interventions. Although disruption of calcium by IVL may obviate the need for conventional aggressive balloon dilations, the risk of distal atherothrombotic embolization still remains despite the use of cerebral protection devices. In our case, we utilized the Emboshield EPD and we wonder if the proximal EPD such as Mo.Ma Ultra (Medtronic, Minneapolis, MN, USA) 4 that maintains flow arrest before the lesion is crossed by any device, thereby preventing microembolization, would have been effective in preventing this complication.
