Cryptogenic Stroke or Stroke of Unknown Cause

In most cases, a stroke is caused by a blood clot that blocks blood flow to the brain. But in some instances, despite testing, the cause can’t be determined. Strokes without a known cause are called cryptogenic.

Because approximately 1 in 4 stroke survivors will likely have another stroke event, finding the cause of the stroke will help your physician treat the cause of your stroke and lower the likelihood of another. Having a cryptogenic stroke may be frustrating and overwhelming, but with a proper diagnostic workup and collaboration with your healthcare team, you can take part in finding the cause of your stroke and help prevent another one from occurring.

Below, we have information and resources that can help you and your loved ones partner with your healthcare team and find answers around cryptogenic stroke.

It’s estimated that about 1 in 3 ischemic strokes are cryptogenic. 

Some studies suggest that the incidence of cryptogenic stroke is higher in African-Americans (two times more likely) and Hispanics (46% more likely).

Possible Hidden Causes of Stroke

• Irregular heartbeat (atrial fibrillation) – AFib patients are at a 5 times greater risk for stroke.
• Heart structure problem (such as Patent Foramen Ovale)
• Hardening of the arteries (Large Artery Atherosclerosis)
• Blood clotting disorder (Thrombophilia)

During your hospital stay and follow-up care, you will want to discuss with your physician the ways to best treat and prevent another stroke. Some of these discussions may include diagnostic testing, blood work-ups and lifestyle changes.

While the cause of your stroke may not yet be determined, it is important to follow your physician’s medical advice and take your medications. If you receive a heart monitoring device, you will also want to follow any heart monitoring regimens prescribed. Additionally, you may reduce your risk factors for stroke by following a healthy lifestyle. Here are eight behaviors AHA has identified, called Life’s Essential 8^®, to help you minimize the risk of another stroke.

Use our information and resources that can help you and your loved ones partner with your health care team and find answers about cryptogenic stroke.