Sharing 10-year findings from the ACST-2 trial at the 39th European Society for Vascular Surgery (ESVS) annual meeting (23–26 September, Istanbul, Türkiye), Alison Halliday (University of Oxford, Oxford, UK) highlighted that, if successful, both carotid artery stenting (CAS) and carotid endarterectomy (CEA) “substantially reduce long-term stroke rates”.
ACST-2 is an international, multicentre, randomised controlled trial (RCT) of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. “Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either CAS or CEA can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death,” Halliday and colleagues write in a 2021 Lancet paper outlining five-year results.
The trial involved 3,624 patients, with 1,810 allocated to CAS and 1,814 to CEA. The patients were randomised between 2008 and 2020 at 130 centres across predominantly Europe.
Summarising the long-term stroke risk of CAS versus CEA, Halliday reported that antiplatelet, antithrombotic and lipid-lowering therapy use was good (85%, 85% and 84%, respectively), with more intense lipid-lowering therapy rising in both groups from about 10% to about 60%.
The presenter continued that first stroke rates were similar between the two groups (113 for CAS vs. 112 for CEA) and that, after excluding haemorrhagic and cardioembolic sources, 91 stokes in the CAS group and 92 in the CEA were “probably or possibly” due to carotid disease.
Furthermore, Halliday shared that 97% ipsilateral and 9% contralateral arteries had 70–99% stenosis, yet after intervention there were fewer ipsilateral than contralateral strokes (46 vs. 73), indicating protective effects of both CAS and CEA. The presenter added that meta-analyses of all the main trials of CAS versus CEA strengthened the ACST-2 findings of comparable effectiveness.
“CAS and CEA both involve about 1% risk of death or disabling stroke,” Halliday said in her concluding statement. “But, if successful, both substantially reduce long-term stroke rates. Both CAS and CEA provide similarly durable protection.”
