surgery for blocked arteries often unwarranted
Brittany Hambleton
Brittany Hambleton
December 10, 2023 ·  5 min read

Surgery For Blocked Arteries Is Often Not Needed, Research Finds

This article was originally published in December 2019 and has since been updated.

The scenario is all-too-familiar: John experiences chest pain, so he goes to see his doctor. The doctor performs some tests, and John finds out that he has some narrowing or blockages in his arteries. Immediately he is sent to a specialist to receive either bypass surgery or a stent to open up the arteries and prevent a heart attack.

To most people, and doctors, this sequence of events seems completely logical, but a recent large federal study has shown that heart surgery may not always be the best solution. The study found that drug therapy can be just as effective as bypass and stenting surgeries [1].

What is Normal Procedure for Blocked Arteries?

Many Americans experience angina, or chest pain, due to lack of oxygen reaching the heart. Typically when this occurs and a patient is found to have blocked or narrowed arteries, they either receive a stent or in some cases bypass surgery.

A stent is a mesh tube that is inserted into the affected artery to hold it open and increase blood flow to the heart [2].

Bypass surgery involves taking a healthy blood vessel from your arm or your leg and connecting it beyond your blocked artery to redirect blood around the blockage and improve blood flow to your heart [3].

Neither of these procedures cures the heart disease that caused the blocked artery in the first place, but it does ease symptoms like chest pain and shortness of breath. It also can improve heart function and decrease the risk of the patient from dying of heart disease [3].

The Trial

The study is called the “International Study of Comparative Health Effectiveness With Medical and Invasive Approaches” or ISCHEMIA for short.

The purpose of ISCHEMIA was to determine the best treatment strategy for patients with ischemic heart disease (aka – heart disease that causes chest pain) [4]. Researchers also wanted to find out whether or not a more invasive strategy, like surgery, would improve a patient’s outcome in areas including risk of death, chest pain, and quality of life, as opposed to a less-invasive drug treatment plan [4].

The study, which included 5179 patients [4], found that patients who received drug therapy alone did not have more heart attacks or experience more chest pain than patients who received a stent or bypass surgery [1].

Dr. Alice Jacobs, director of Cath Lab and Interventional Cardiology at Boston University, remarked that the study will challenge many doctors’ clinical thinking.

You would think that if you fix the blockage the patient will feel better or do better,” she noted [1].

Not New News

This is not the first time a study like this has been published. Similar trials performed in 2012 out of the State University of New York–Stony Brook School of Medicine found that while interventions such as stents and bypasses reduced death in acute situations (ie- when a patient is having a heart attack), it was generally not more effective than medical therapy [5].

Yet another study published in the American College of Cardiology found that surgery did not greatly reduce symptoms or improve quality of life in patients with non-emergency angina over a drug protocol [6].

All of these findings are consistent with what we already know about heart disease. Researchers understand that when a patient has a narrowed artery, it is likely that he or she might have plaques throughout other arteries as well. Stents and bypasses only focus on one singular artery, while medical intervention treats the entire system. This is important since if there are multiple plaques it is impossible to know which one will burst first [1].

Why have doctors pushed back?

Despite these findings, many doctors are still hesitant to forego surgery. 

There is a tendency by both doctors and patients alike to want to rush to the quickest possible solution and solve the problem right away [1]. This, of course, is understandable. When you find out you have a blocked or narrowed artery, your first thought is “how close am I to having a heart attack?” 

There is also a fear among doctors that patients will be resistant to following a long and intensive drug protocol. Many claim that the follow-up required to make sure patients are adhering to a drug protocol are too demanding, and that they don’t have time for it [1].

The Benefits of Foregoing Surgery

While all of the above concerns may be valid, they do not outweigh the benefits of skipping surgery.

The truth is, even patients who receive surgery are still required to follow a drug protocol. Dr. William E. Boden, scientific director of the clinical trials network at VA Boston Healthcare System, explained that patients with stent still need anti-clotting drugs, and usually end up taking more medication than patients who did not have surgery [1].

Stents are also a more dangerous form of treatment and are extremely expensive [2]. As with any type of major surgery, patients are at risk of complications such as major bleeding, and this surgery can add $10 thousand to the cost of treatment [2].

What should patients do?

If you or a loved one is experiencing ischemic heart disease, it is important to talk to your doctor about all your options, and ask what other treatment options are available to you outside of surgery. As always, patients need to take ownership of their health and work with their doctors to figure out the best solution for them.


  1. Surgery for Blocked Arteries Is Often Unwarranted, Researchers Find.” NY Times
  2. Heart Stents Are Useless for Most Stable Patients. They’re Still Widely Used..” NY Times
  3. Coronary artery bypass surgery.” Mayo Clinic
  4. International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) (ISCHEMIA).” Clinical Trials
  5. Initial Coronary Stent Implantation With Medical Therapy vs Medical Therapy Alone for Stable Coronary Artery Disease.” JAMA Network. Kathleen Stergiopoulos, MD, PhD and David L. Brown, MD. February 27, 2012.
  6. Objective Randomized Blinded Investigation With Optimal Medical Therapy of Angioplasty in Stable Angina – ORBITA.” ACC. Rasha Al-Lamee, MD, et al. May 26, 2022.