Stents are metal scaffolds, usually coated in drugs, that can be inserted into narrowed coronary arteries to unblock them.
Stents have been around since the end of the last century and have been getting better ever since – more flexible and now have drugs on them.
Initially these were used for stable patients with angina to relieve symptoms. Over the last couple of decades, we have shown that they are brilliant treatments for heart attacks.
But it’s taken until now to for someone to do a proper randomised, controlled trial to look at their use in stable patients.
Dr Al-Lamee and colleagues from Imperial College and across the UK published the ORBITA study in the Lancet last week.
This is a landmark study which looked at patients with chest pain on exertion, treated them with medicines. and if they still had angina randomised them to either a stent or a sham procedure.
A sham procedure is one where catheters are placed in the heart, but no stents are placed. The patient stayed on the operating table for some time, the patient had headphones on and didn’t know if they were getting a stent or not, and the doctors in the cath lab doing the procedure weren’t involved in the patient’s care afterwards. A proper double blind (neither the patient nor the treating doctors) knew which treatment that they had.
6 weeks later they looked at symptoms using questionnaires and exercise capacity. There was no difference between the groups!
This is a shocking result.
They clearly had enough patients to detect a difference (it was sufficiently powered), they demonstrated significant blockages that were successfully unblocked with stents, but it made no difference to the patients.
The article suggests that worldwide there may be 500,000 stents placed in patients similar to those studied in this paper – this paper may well change guidelines and practice.
Great to see the UK leading the world in doing proper, useful research that changes how we treat patients. Also there are lessons to be learned in how we improve treatment with medications.