Once every seven minutes, a Medicare patient gets a cardiac stent they don’t need.” “Coronary stent overuse is running rampant.” Those were headlines you may have seen in October 2023. A study from a health advocacy think tank, the Lown Institute, warned that cardiac stents were being overused. They reported that between 2019 and 2021, one in five cardiac stents for Medicare patients were unnecessary based on the current guidelines. Those stats might lead you to think that a lot of interventional cardiologists—the doctors who place the stents—are taking advantage of the elderly. But as is often the case, there is more to this story.
Although heart disease is still the leading cause of death for Americans, deaths from heart attacks have gone down by over 40 percent in the last 20 years. A major reason is a procedure called angioplasty with percutaneous coronary intervention (PCI). Almost all of these procedures include a cardiac stent. About 1.2 million cardiac stents are placed every year in the United States.
When an artery that supplies the heart muscle is narrowed by coronary heart disease (arteriosclerosis), decreased blood supply to the heart causes a type of chest pain called angina. If the artery blocks, a heart attack occurs. During PCI, a catheter is placed into a blood vessel through the skin and advanced to reach a diseased coronary artery. A balloon at the end of the catheter is inflated to restore blood flow, called revascularization, and an expandable metal tube, called a cardiac stent, is left behind to maintain blood flow. Theses stents can restore blood flow during or after a heart attack. They can also prevent a heart attack and relieve angina. Before PCI, the only way to restore blood flow was open-heart surgery, called a coronary artery bypass.
According to current guidelines, stent placement is beneficial for a person having a heart attack or a person with unstable angina. Unstable angina is chest pain that starts without warning, gets progressively worse, and does not get better with rest or medication. Unstable angina should be treated as a medical emergency.
Stable angina is chest pain that comes and goes. It is usually triggered by activity and improves with rest or medication. For stable angina, a stent is placed to relieve symptoms, not to save a life. The Lown study says that years of research have shown that stents for stable angina are not more beneficial than medication management.
This is true to a point. However, guidelines are suggestions, not rules, and many cardiologists have not been convinced that stents should not be used for stable angina. The current guidelines rely heavily on the 2017 ORBITA trial. This study compared people with stable angina treated with a stent to people given a simulated stent procedure, but without an actual stent, called the sham or placebo control group. ORBITA found that the stenting for stable angina did not offer any benefits over the sham procedure with medication management. The trial has been criticized for its small sample size and short follow-up.
Some cardiologists also questioned the guidelines because they had seen significant improvement in patients with stable angina who could not tolerate medications, or because they had a more dangerous type of stable angina due to disease in the left anterior descending artery (LAD) called the “windowmaker.” Because of this danger, a stent is often placed for heart attack prevention, even if they have stable angina.
About the same time that the Lown press release came out, a new study, called ORBITA 2, was being presented at the November meeting of the American Heart Association. This trial was bigger and lasted longer than the first ORBITA, and it did find stent benefits for people with stable angina.
ORBITA 2 included more than 300 patients with an average age of 64. The patients were randomly assigned to receive a cardiac stent or a simulated procedure that did not include a stent. All patients were taken off their chest pain medications before the study started. After the procedures, their doctors could put them back on medication as needed.
In ORBITA 2, patients with stents were three times more likely to be free of pain and not need medication. They also had increased exercise tolerance and an improved quality of life. The results did not surprise many cardiologists and they confirmed the pretrial hypothesis of the research team.
The researchers concluded that stent placement for control of stable angina symptoms can be an option based on the risk-benefit profile of an individual patient, and that current European and American guidelines may require updating.
The PCI stent procedure is relatively safe, but not without risks, including bleeding or infection at the catheter insertion site, blood clot or damage from the catheter, abnormal heart rhythm, and, more rarely, heart attack or stroke. The best advice is to make a shared decision with your doctor, balancing the risks and benefits based on your health, your age, your tolerance of medication, your activity level, and other factors.
