While metal stents of various kinds have worked wonders in coronary artery disease in most parts of the world, they have yet to register the same kind of success in preventing re-occlusion of intracranial blood vessels. Professor Werner Hacke of Heidelberg Medical School, while speaking at an international Neurology Update in Mumbai on Friday, stated this.
There is hardly any evidence to show that stents placed in the middle cerebral artery (MCA) offer any significant benefit over the existing procedures like cranial endarterectomy (CEA), Dr Hacke explained.
“The studies that we have seen till now are in the nature of registry listings or single center studies,” he said, as an audience of more than 500 medical people listened with rapt attention.
In a scathing criticism of the procedure, the former dean of Heidelberg Medical School described a Wall Stent Study, which had catastrophic results and another 2001 study (published in Lancet), which showed equally high morbidity in both arms. Both failed to demonstrate any superiority of the stenting procedures.
Professor Hacke also pointed out that many of the studies currently available were either company driven or had the holder of the device patent as the principal investigator! He also claimed that since the procedures and subsequent follow up were invariably carried out by interventional cardiologists, the assessment of outcomes was less than adequate.
“Often the real cause of poor outcomes being reported was the presence of the neurologist on the team,” he said in a jocular vein.
This was however set to change very soon, since at least four major controlled trials were underway, and their results would start coming within two or three years. Among these is one being conducted by the International Carotid Stenting Society (ICSS) and another known as the SPACE study, which began in 2001. The SPACE study has already recruited over 600 patients and the results are expected to be published late next year.
Ironically, in Europe the widely accepted CEA procedure costs more than stenting, although in India, the situation is exactly the reverse.