A standard time limit for carotid artery stenting procedures was suggested by Giorgio Biasi of the University of Milano-Bicocca, Italy, speaking at the International Congress on Endovascular Interventions XXII in Scottsdale, Arizona, USA, this month.
Biasi presented the final results of the RISC study (Registro Italiano per lo Stenting Carotideo), a study of 1,350 cases, which found that the minimally-invasive procedure has good long-term results, both in terms of neurological complications and restenosis.
The study aimed to collect data on carotid artery stenting in a “real world” setting.
The data was compiled by professionals from across disciplines concerned with preventing stroke due to carotid plaques. “The interesting point is,” said Biasi, “that the major components – vascular surgeons, radiologists and cardiologists – were roughly equally represented.”
Each of the study centres was free to use different techniques and devices.
Patient follow-up took place at one, six, 12 and 24 months with computed tomography or magnetic resonance imaging, always in the presence of an independent neurologist. The primary endpoints of the study were 30-day combined any stroke and death rate, restenosis at 24 months, and stroke and death rate at 24 months.
The study found a 30-day stroke and death rate of 2.4%. Biasi highlighted a peak in complication rates in patients aged between 70 and 80 years, which fell in those over 80 years of age.
A difference between experienced and inexperienced centres (those that had performed more or less than 30 procedures respectively) was observed, but this, he said, was not found to be significant (p=.09). He also showed that the data strongly supported statin administration and the use of embolic protection devices.
“The total procedure time was very important. When the time was over 60 minutes, there was a great difference from those taking less than 30 minutes,” he said.
“The presence of calcified plaques is also very important [increasing the chance of stroke and death], and the least important factor is the percentage of stenosis.”
The study found no statistically significant difference between open and closed cell stent designs.
Beyond 30 days, there were 23 deaths up to two years, 15 of which were from non-neurological causes. There were 13 strokes recorded in this period and a rate of new restenosis of 4.4%.