A dent on the viablility of DES usage

MUMBAI: Concerns have been raised over Drug Eluting Stent (DES), a device using to remove blockage to the artery in cardiac patients, forcing a rethink among cardiologists about its use. DES was much sought out by cardiologists over the conventional bare metal stent (BMS). But now, an observation that patients who use DES have more chances of developing late stent thrombosis (LST), have forced a review about it among cardiologists.

Stents, small wire-mesh tubes inserted in blocked arteries to keep them open, became popular as a safe alternative to bypass surgery.

Of the 70,000stents used in the country a year, 60% are DES. According to studies 11% of the adult population are cardiac patients. Out of the 80 million cardiac patients in India, 20% face acute cardiac problems that needs operation.

“LST may happen after six months of implantation of DES, which may leave patients’ life at stake. In case of BMS, thrombosis may happen within 3 months, where the chance to save patient is more. This forces a rethink on the use of DES,” said Eric Borges, consulting cardiologist, Bombay Hospital.  Concerned over a possible of LST, the US FDA recently recommended that a warning be added to the DES labels stating that its use may increase risk of thrombosis and death. Moreover, the FDA has advised that the labels should carry a recommendation that aspirin and plavix combination treatment should continue for 12 months when DES are implanted off-label. Plavix (clopidogrel bisulfate) is widely used blood-thinning drug.

Dr G R Kane, Interventional cardiologist, Hinduja Hospital, Mumbai, agrees that there are cases of LST reported in the country. “There are deaths due to LST reported here. But it is mainly due to stoppage of drugs that are supposed to be consumed if the DES is implanted. Patients are asked to take drugs like clopidogrel and aspirin for 10 months, if the DES is implanted in them. We urge them not to stop the drugs without consultation,” he said. In Hinduja hospital alone, there are 5-6 stent implantation cases a day, out of which 70% are DES.

The widely used DES in India are Taxus and Cypher, manufactured by Boston Scientific and Johnson& Johnson respectively. Indian companies that make DES include Relisys Medical Devices, Opto Circuits, Sahajanand Medical Technologies, Vascular Concepts, India Medtronic etc. However, lack of FDA approval and insufficient data make locally-made stents less sought after.

The number of DES implantation in the US decreased to almost 20-25 % at the beginning of 2007, from a high of 90 % during 2006, due to the concerns on possibility of late stent thrombosis (LST).