November 19, 2018
VQI Study Shows Similar Outcomes for TCAR Versus CEA, With Lower CNI and OR Time
November 20, 2018—Transcarotid artery revascularization (TCAR) showed similar rates of in-hospital stroke and death yet shorter operating room (OR) time and fewer cranial nerve injuries (CNIs) than carotid endarterectomy (CEA) in a study presented at the 2018 VEITHsymposium in New York, New York.
Initial "real-world" comparative data derived from centers participating in the Society for Vascular Surgery (SVS)'s Vascular Quality Initiative (VQI) were presented by Marc Schermerhorn, MD, of Beth Israel Deaconess Medical Center in Boston, Massachusetts. The goal of the VQI TCAR Surveillance Project (TSP) study was to compare the outcomes of TCAR and CEA using the Enroute flow-reversal system (Silk Road Medical) in a setting outside of typical clinical trials, which Dr. Schermerhorn described as generally involving highly selected patients and providers. Stenting via TCAR aims to reduce the stroke rate associated with transfemoral carotid artery stenting by employing flow reversal and an access method that avoids passing through the aortic arch.
In the data presented at VEITH, the VQI TSP study evaluated outcomes of patients treated with TCAR (n = 2,545) or CEA (n = 43,114) and submitted to the VQI database between January 2016 and September 2018. In-hospital stroke and death was the primary outcome measured; secondary outcomes included stroke, death, and myocardial infarction (MI) (composite and individually), 30-day mortality, and access site bleeding, CNI, hyperperfusion syndrome, and operative time. Key baseline characteristics included that TCAR patients were more likely to be older, have cardiac/coronary disease, chronic kidney disease, and prior carotid revascularization, and less likely to be female. General anesthesia was used less frequently with TCAR than CEA.
The unadjusted outcomes rate of stroke and death in the TCAR arm was 1.8 versus 1.4 in the CEA arm (P = .09), and the rates of stroke alone were 1.4% and 1.2% in the two arms, respectively (P = .27). Although in-hospital death was slightly higher in the TCAR arm at 0.5% versus 0.3% (P = .04), Dr. Schermerhorn recalled that the TCAR patients tended to be older and have more cardiac disease. He highlighted a dramatically lower incidence of CNI—0.2% for TCAR and 2.7% for CEA (P = < .001). The operative time observed for CEA was 41 minutes longer than that of TCAR on average (116 ± 45 vs 75 ± 31 mins; P < .001), and length of stay > 1 day was slightly more common after CEA.
"Every minute counts in a clinical day [for operators], and the significance for the hospital is huge because OR time is very expensive," said Dr. Schermerhorn regarding the 41-minute drop in OR time seen with TCAR.
Multivariable logistic regression analyses, propensity score-matched analyses, and outcomes adjustment by symptom status all confirmed what Dr. Schermerhorn called "strikingly similar" outcomes between the two groups, with the only significant difference seen in the lower rate of CNI for TCAR in each review.
"Most [CNIs] are temporary and are gone within a year, but if you can't swallow well and you're speaking with hoarseness, even just for a few months, it's not pleasant," said Dr. Schermerhorn in comments to Endovascular Today after the presentation. "If we can avoid it without paying a cost of increased stroke risk, as you would have with transfemoral stenting, I'll take it."
Next, 1-year follow-up data and results with larger sample sizes will be gathered and presented. Dr. Schermerhorn confirmed the study will also explore how operators perform as they progress through the learning curve of the new approach to carotid stenting. Through September, 39% of the carotid stent placements recorded in the VQI in 2018 were performed via TCAR, a number he said is rising rapidly.
"This study highlights the utility of the SVS VQI to evaluate new technology," said Dr. Schermerhorn, noting that the VQI TSP study is the first of its kind and was designed together with the US FDA and CMS (Centers for Medicare & Medicaid Services). The agencies gain a sizable dataset on a new technology, and operators can gain reimbursement for the carotid revascularization patients they simultaneously enroll in the VQI and the clinical trial, while data gathered in the study could also inform potential future coverage decisions, Dr. Schermerhorn believes.