Patients mulling whether to get a common procedure to unclog blocked arteries may not get enough information from their doctors to make the best choice, a small study suggests.

Researchers analyzed recordings of 59 conversations between cardiologists and patients about a common procedure called percutaneous coronary intervention (PCI), which is done to reopen arteries and restore blood flow to the heart - and found just two discussions covered all the points needed for patients to make an informed decision.

“When you are facing a decision that has a number of consequences one way or the other, there are a number of issues that you are supposed to address and we found, overall, that very few conversations had all the elements,” said Dr. Michael Rothberg, of the Center for Value Based Care Research at Cleveland Clinic in Ohio.

The procedure, also referred to as a balloon angioplasty, involves attaching a tiny deflated balloon to special tubing that’s threaded through arteries to the site of the blockage. Then, surgeons inflate the balloon to clear away the debris, often leaving a tiny wire mesh cage called a stent inside the vessel to prevent future clogging.

While the procedure can relieve pain and prevent heart attacks in some patients, it doesn’t benefit everybody and it also carries risks such as infections, damage to blood vessels or a ruptured artery that requires open-heart surgery to repair.

“Having a PCI if you don’t really need one is not something an informed patient would do,” said Floyd Fowler, Jr., a senior scientific advisor at the Informed Medical Decisions Foundation who wasn’t involved in the study. Without enough information about the advantages and harms of a procedure as well as any alternative treatments, patients may overestimate the benefits of surgery, he said by email.

The study focused on patients considering the procedure to relieve symptoms of chronic stable angina, a type of chest pain that can flare up as a result of exercise or stress and can sometimes be managed with rest or medication.

Doctors discussed alternative treatments just 25 percent of the time, and were even less likely to take time to confirm whether patients understood information or to explain the pros and cons of different stents that might be used during surgery.

In most conversations, physicians recommended the procedure and when they did, most patients followed their advice. In the rare instances when doctors didn’t express an opinion or recommended against the procedure, patients always listened.

Most patients with chronic stable angina falsely believe that this operation can prevent heart attacks or death, even though its main benefit is easing chest pain, the researchers note in JAMA Internal Medicine.

“Patients should be asking if the treatment will affect how long they live or prevent an event like a heart attack,” Dr. Grace Lin, an internist at the University of San Francisco Medical Center and co-author of an editorial published with the study, said by email. “Patients should consider asking for a second opinion if they feel like they haven’t been given all the information they need in order to feel comfortable making a decision.”