You know the risk stemming from completely blocked arteries—heart attack. But did you know that a minor blockage is enough to cause a heart attack in some people…and that doctors tend to minimize the severity of this type of heart attack? Now, a new study finds that there is definitely cause for concern, especially among women.

We’re talking about MINOCA, the acronym for a myocardial infarction (heart attack) with non-obstructive coronary arteries, somewhat of a mystery compared to more common heart attacks…and under-researched…but dangerous.

Typically, MINOCA has been thought of, and treated, as a less serious type of heart attack. It’s not unusual for MINOCA patients to be reassured and sent home from the hospital after experiencing one without the level of care prescribed to other heart attack victims and without a real focus on preventing another heart attack.

But when researchers at the University of Alberta in Canada reviewed the medical records of almost 36,000 patients admitted to hospitals for any type of heart attack, they found startling results…

  • Only 6% of these heart attack patients did not have blocked blood flow to the heart—meaning their heart attacks were MINOCA. Yet, during the next five years, 11% of these MINOCA patients went on to have second heart attacks or died, showing just how strongly MINOCA can influence future health.
  • Only 25% of heart attack patients with blocked arteries were women, but 50% of MINOCA patients were women.
  • Only about 40% of MINOCA patients were put on medications to prevent future heart attacks. And women with MINOCA were likely to be treated with hormone replacement therapy—which does not help to reduce heart attack risk—or antidepressants instead.
  • The average age of MINOCA patients was 59, about 4 years younger than for a blockage heart attack.

Clearly, there’s a heart danger stalking middle-aged people that is not being taken seriously enough, especially with female patients. The key takeaway from this study is that MINOCA is a serious type of heart attack and should be approached that way by both patients and doctors. Although the exact cause of MINOCA remains a mystery, possibilities include a temporarily blocked artery due to a blood clot or a spasm of an artery due to atherosclerosis. In reality, people who get a MINOCA do have diseased coronary arteries. They may have plaques like other heart attack patients and some narrowing of a coronary artery but not enough to cause a complete blockage.

Why women are more affected by MINOCA remains another part of the mystery. Researchers suspect that female hormones may cause a weakening or dysfunction of the inside lining of heart arteries, making them more susceptible to atherosclerosis spasms, but more research needs to be done.


Risk factors for MINOCA are similar to risk factors for other heart attacks—high blood pressure, high cholesterol, diabetes, smoking and a family history of heart attack. So, according to the American College of Cardiology, you can reduce your risk of MINOCA with the same heart-healthy lifestyle habits everyone should be following, such as eating healthy, staying active, managing stress and not smoking.

Also, keep in mind that a MINOCA heart attack can feel like any other heart attack with severe chest pain, but it doesn’t have to—women, for example, often have milder symptoms such as shortness of breath, nausea, vomiting, dizziness and back or jaw pain. Man or woman, if you have these symptoms, call 911 right away.

The strongest takeaway from this eye-opening study concerns what to do if you do have a MINOCA heart attack: Treat it seriously and do not let your doctors do otherwise. Tell them about this article if that’s what it takes. Then, the good news is that you should respond to the same prevention strategies used by people who have had more traditional types of heart attacks, including medications such as statins, beta-blockers and others. But if your doctor persists in telling you that your MINOCA was not that serious, get another opinion.

Related Articles