Dual Antiplatelet Alternatives are Associated With Increased Stroke and Death After Transcarotid Revascularization.

OBJECTIVE: To define the risks associated with the replacement of dual antiplatelets for alternate medication regimens. BACKGROUND: Patients undergoing transcarotid artery revascularization (TCAR) for atherosclerotic disease in the Vascular Quality Initiative database from September 2016 to June 2022 were included. In all, 29,802 TCAR procedures were captured between 2016 and 2022, consisting of 24,651 (82.7%) maintained on dual antiplatelet therapy (DAPT) and 5151 (17.3%) on alternative regimens. METHODS: Patients maintained on DAPT were compared with those on alternative regimens consisting of any combination of single antiplatelet monotherapy and/or anticoagulation. RESULTS: On univariable analysis, patients on alternative medications were more likely to experience in-hospital death, ipsilateral stroke, any stroke, and transient ischemic attacks compared with patients in the DAPT group. The mortality rate was higher at 1 year in the alternative cohort (4.7% vs 7.0%, P <0.01). The use of alternate medication regimens was associated with increased odds of stroke and the composite outcome of in-hospital stroke/death compared with DAPT. There was also a significant association between alternative medication use and increased odds of in-hospital transient ischemic attack, immediate stent occlusion, and return to the operating room. At 1 year, there was no significant difference in the incidence of stroke between the 2 groups. However, the use of alternate regimens was associated with higher 1-year of mortality after multivariable adjustment. CONCLUSIONS: Patients not maintained on DAPT after TCAR experienced an increased risk of stroke and death in the perioperative and follow-up periods. Increased surgeon vigilance is required to ensure compliance with dual antiplatelets as recommended.

Multi-institutional patterns of clopidogrel response among patients undergoing transcarotid artery revascularization.

OBJECTIVE: Current guidelines recommend dual antiplatelet therapy (DAPT) in patients undergoing carotid artery stenting. The most common DAPT regimen is aspirin and clopidogrel, a P2Y12 receptor antagonist; however, the prevalence of clopidogrel resistance (CR) in patients undergoing percutaneous coronary interventions may exceed 60%. Few studies have investigated the prevalence and impact of CR in patients undergoing extracranial carotid artery stenting, particularly transcarotid artery revascularization (TCAR). METHODS: Consecutive high-risk patients ≥ 18 years who underwent TCAR for high grade (≥70%) and/or symptomatic (≥50%) carotid stenosis with preoperative P2Y12 testing between August 2019 and December 2021 were identified across five institutions. Preoperative platelet reactivity was measured with the VerifyNow P2Y12 Reaction Unit (PRU) Test (Instrumentation Laboratory, Bedford, MA), with CR defined as PRU ≥ 194 and hyper-response as PRU <70. Patients without preoperative P2Y12 testing within 30 days prior to TCAR or those on a non-clopidogrel P2Y12 inhibitor preoperatively were excluded. The primary outcome of interest was prevalence of CR. Secondary outcomes of interest included the incidence of ischemic and hemorrhagic complications. RESULTS: Of 92 patients identified, the majority were male (59%) and Caucasian (75%) with a mean age of 75 years (±8, range 56-92). Preoperatively, 93% of patients were on aspirin, 100% on clopidogrel, and 13% on therapeutic anticoagulation. At presentation, 36% were symptomatic. The mean preoperative P2Y12 was 156 PRU (±76, range 6-349). In total, 30 (33%) patients met criteria for CR (mean PRU 240 ± 37; range 197-349), and 15 (16%) met criteria for hyper-responder (mean PRU 38 ± 20; range 6-68). There was no significant difference by clopidogrel response phenotype in terms of sex (p = 0.246), race (p = 0.384), or symptomatic presentation (p = 0.956). Postoperatively, the cumulative incidence of stroke and MI was 2.1%, with no statistically significant difference in the incidence of in-hospital stroke (PRU 238, p = 0.489) or MI (PRU 168, p = 1) between clopidogrel phenotypes. Three (3.3%) patients, one CR (PRU 240) and two responders (PRU 119 and PRU 189), experienced postoperative access site hematomas that required no subsequent intervention. No other index hospitalization hemorrhagic complications occurred. CONCLUSIONS: Using preoperative P2Y12 testing with a threshold PRU ≥ 194 to define CR, we identified a high prevalence of CR in patients undergoing TCAR similar to that in the pre-existing coronary literature. We found no significant differences in postoperative ischemic or hemorrhagic complications by clopidogrel response phenotype, although complication rates in the overall study cohort were low. CR may be a spectrum from responder to partial responder to complete non-responder, and this may account for the differences in our CR cohort compared to the ROADSTER 2 protocol deviation cohort. Further investigation is warranted to determine if a quantitative assessment of CR is sufficient to identify patients at risk of developing secondary cerebrovascular ischemic events in this patient population.

Aggressive Surveillance Is Needed to Detect Endoleaks and Junctional Separation between Device Components after Zenith Fenestrated Aortic Reconstruction.

BACKGROUND: Junctional separation and resulting type IIIa endoleak is a well-known problem after EVAR (endovascular aneurysm repair). This complication results in sac pressurization, enlargement, and eventual rupture. In this manuscript, we review the incidence of this late finding in our experience with the Cook Zenith fenestrated endoprosthesis (ZFEN, Bloomington, IN). METHODS: A retrospective review was performed of a prospectively maintained institutional ZFEN fenestrated EVAR database capturing all ZFENs implanted at a large-volume, academic hospital system. Patients who experienced junctional separation between the fenestrated main body and distal bifurcated graft (with or without type IIIa endoleak) at any time after initial endoprosthesis implantation were subject to further evaluation of imaging and medical records to abstract clinical courses. RESULTS: In 110 ZFENs implanted from October 2012 to December 2017 followed for a mean of 1.5 years, we observed a 4.5% and 2.7% incidence of clinically significant junctional separation and type IIIa endoleak, respectively. Junctional separation was directly related to concurrent type Ib endoleak in all 5 patients. Three patients presented with sac enlargement. One patient did not demonstrate any evidence of clinically significant endoleak and had a decreasing sac size during follow-up imaging. The mean time to diagnosis of modular separation in these patients was 40 months. Junctional separation was captured in surveillance in 2 patients and reintervened upon before manifestation of endoleak. However, the remaining 3 patients completed modular separation resulting in rupture and emergent intervention in 2 and an aortic-related mortality in the other. CONCLUSIONS: Junctional separation between the fenestrated main and distal bifurcated body with the potential for type IIIa endoleak is an established complication associated with the ZFEN platform. Therefore, we advocate for maximizing aortic overlap during the index procedure followed by aggressive surveillance and treatment of stent overlap loss captured on imaging.