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Categories > Heart Health > Heart disease: Symptoms

Silence isn’t golden
No warning

Know your risk factors
Know your risk factors

You’re more prone to suffer from ischemia, which may be silent, if you have a history of:

  • prior heart attacks
  • coronary artery disease
  • diabetes
  • high blood pressure
  • smoking
  • obesity
  • heart muscle disease
  • alcohol and drug abuse

If you were having a heart attack, you’d feel warning signs, right? Isn’t chest pain a surefire way to tell whether something is not right with your heart?

Not necessarily. If you suffer from a condition called silent ischemia (is-keé-mee-a), you could be close to a heart attack and not even know it. In fact, the American Heart Association estimates that as many as 3 million to 4 million people suffer from the condition.

No warning

When an artery becomes blocked or narrowed by plaque, it can temporarily cut off oxygen-rich blood to the heart. This is a condition known as cardiac ischemia.

In most of these cases, chest pain or discomfort—also known as angina—occurs, alerting you that your heart needs help. But if you suffer from silent ischemia, you’ll feel no pain. Without a warning sign, you’ll likely not seek medical help and receive treatment. Without proper care, subsequent episodes of silent ischemia can further damage your heart and eventually lead to a heart attack. Heart muscle damage caused by silent ischemia is one of the most common causes of heart failure in the United States.

It’s unclear why some people don’t feel the traditional chest pain, although people who have diabetes may not feel anything because their condition causes a decreased sensitivity to pain.

Silent ischemia can also cause serious and potentially fatal abnormal heart rhythms. And you don’t have to be running a marathon to have an attack; a bout of silent ischemia can occur from the simplest actions, such as doing a math problem.


To diagnose silent ischemia, your healthcare provider tests how your heart responds to exercise. During a stress test, you’ll walk on a treadmill to monitor how well your blood flows through your coronary arteries. Or you may be asked to wear a Holter monitor. This recording device tracks your heart rate and rhythm over a set period—usually for 24 to 48 hours—to determine whether you’ve experienced any episodes of silent ischemia.


Lifestyle changes are usually the first line of defense against the condition. These include:

  • quitting smoking
  • lowering high blood pressure and cholesterol
  • controlling diabetes
  • limiting alcohol
  • eating healthfully
  • exercising

In addition to lifestyle changes, your healthcare provider may prescribe medication to improve blood flow to the heart, such as aspirin and anticoagulants to stop clots from forming. For people who don’t respond well to medicine, angioplasty or bypass surgery may be required.