On Wednesday, medical journal The Lancet published a study that has questioned the common cardiac procedure of inserting stents into blocked arteries of patients with chest pains as one of the symptoms of heart disease. A stent is a short wire-mesh tube that acts as a scaffold to keep a blocked artery of the heart open. The study shows that stents do not necessarily alleviate chest pains when patients exert themselves. The results of the study have stunned cardiologists, The New York Times reported, as it counters decades of clinical practice.
The study brings back into focus the practice of irrational use of cardiac stents globally and in India.
The study recruited 200 patients with severe artery blood vessel blockage, who experienced ischemic symptoms that arise when blood flow becomes impaired resulting in chest pain, fatigue, dizziness and palpitations. In such patients, doctors recommend angioplasty – a procedure in which a stent is inserted in the narrowed artery using a catheter. The study involved a control group that underwent a placebo procedure, where the catheter was inserted into the body but no stent was placed in the artery. After six weeks of medication to control heart disease as well as to ease chest pain, the patients who had stents placed and the control group both reported no significant difference in their ability to exercise.
Blockage in a heart vessel may be treated in three ways – medication, stenting or bypass surgery.
A 2012 study showed that bypass was a better treatment modality for patients with diabetes and multivessel blockage as compared to angioplasty.
“We have known that a stable patient with stable angina and block need not undergo angioplasty for years now,” said Dr Sundeep Mishra, a consulting cardiologist at All India Institute of Medical Sciences, Delhi. “For some reason, it still continues.”
Stable angina refers to people with narrowed vessels in their heart but either with no symptoms, or those who feel chest pain or heaviness only during physical activity.
Mishra was referring to a major trial conducted in the United States and Canada 10 years ago, which showed that patients with stable coronary heart disease who underwent angioplasties with medical therapy did not have lower risks of heart attack or death from heart disease as compared to patients who were on medical therapy alone.
Angioplasties are, however, still considered essential for people with unstable angina, where a partial or total block to a blood vessel can cause a heart attack. In such cases, the patient suffers chest pain even while resting. The procedure is lifesaving during a heart attack.
“Stents are a good solid method of treatment,” said Dr Suresh Joshi, a cardiac surgeon from Jaslok Hospital in Mumbai. “But, the indiscriminate use is just increasing over the years.”
The use of stents to treat stable angina and chest pain may largely be due to pharmaceutical company promotions.
For instance, Abbott Healthcare and other multinational pharmaceutical companies marketed a bioresorbable stent as the latest innovation that was superior to the drug-eluting stents commonly used. While regular stents have a metal scaffold, the scaffold in bioresorbable stents are made of material that dissolves in the blood vessel over a period of time. The supposed advantage of a bioresorbable stent is that the device is no longer needed after the blood vessel has healed and can be disposed of within the body.
However, there was little clinical evidence to show that bioresorbable stents are superior to drug-eluting stents. After the US Food and Drug Administration and other regulatory agencies raised concerns that bioresorbable stents might actually increase risks of adverse cardiac events, Abbott decided to withdraw the product from several global markets, including India. The NPPA allowed the product to be withdrawn on safety grounds.
While there is no data to show that stents are being used irrationally in India, public health experts and doctors say that such overuse is indicated by the way in which cardiac treatment procedures are prescribed and the amount of money that patients spend on them.
“The catastrophic spending on this procedure is linked to the business model which involves commissions to hospitals and kickbacks to doctors,” said Malini Aisola of the All India Drug Action Network, a group of nonprofit organisations that works towards increasing access to medicines. “It would not be unreasonable to expect that there would be some level of irrational stenting.”
In February this year, the National Pharmaceutical Pricing Authority or NPPA fixed a ceiling price for stents at approximately Rs 30,000. Apart from increasing access and affordability of the devices, health activists expect that the price cap may also reduce irrational use of stents.
India has no standard treatment guidelines on managing coronary heart disease or on the use of stents.
In 2016, seven leading cardiologists in the country put together detailed guidelines for the management of stable coronary heart disease, that were published in the Indian Heart Journal. These were supposed to be a quick guide for those clinicians inundated with data who “may not have sufficient time to go through” it all. Mishra, who is one of the authors of the guidelines, said that stents should be used in case of profound blockages in some major arteries in the heart or a heart attack. In case of stable heart disease, the disease can be managed by medications, and only if it does not work do cardiologists have to resort to either use of stents or bypass.
“We need standard treatment guidelines in the country,” said Aisola. “We also need to have medical audits that can give us some idea about the extent of irrational use of stents.