Abstract TP154: Characteristics and Surgical Outcome of Patients With Carotid Stenosis Resistant to Medical Therapy

Abstract

Background: The recent progress of medical therapy has made the surgical indication for carotid artery stenosis more stringent. Therefore, surgical outcome of patients resistant to medical therapy were compared with those non-resistant to medical therapy. Methods: Between August 2006 and September 2017, 320 consecutive carotid revascularizations (CEA/CAS) were performed in our institute. Resistant (R) group was defined as patients with crescendo TIA, repeated TIA/infarction despite of medical therapy (n=15) or patients with symptomatic mobile plaque (n=5) (total 18; 2 patients overlapped). Other patients with symptomatic (116) and asymptomatic (186) stenosis were defined as non-resistant (N) group (total 302). Clinical characteristics, magnetic resonance (MR) plaque imaging, plaque pathology, and long-term outcomes with survival analysis were investigated. Results: 13 CEA and 5 CAS were performed in R group. 181 CEA and 121 CAS were performed in N group. The periprocedural stroke & death rate was higher in R group (1/18 [5.6%]; CEA 0/13, CAS 1/5 [20%]) than in N group (9/302 [3.0%]; CEA 4/181 [2.2%], CAS 5/121 [4.1%]) but no significant difference was observed. Signal intensity ratio of plaque relative to sternocleidomastoid muscle was significantly higher in R group than in N group (1.9 vs 1.5, p = 0.007; Fig. 1A) in MR plaque imaging study, which was consistent with intraplaque hemorrhage in pathological findings of R group. Estimates of the 4-year event rate of primary end point (stroke/death/MI within 30 days, and any ipsilateral stroke thereafter) using competing risk analysis were 18% for R group and 4.5% for N group (P = 0.022; Fig. 1B). ALL recurrence occurred after CAS. Conclusion: The resistance to medical therapy was likely to be due to severe intraplaque hemorrhage, which might explain relatively poor outcome of CAS in R group. Appropriate indication is critical for good outcome of R group.