Secondary strokes can be avoided

Thanks to the quick response of his wife and medical staff, Stéphane survived and was left with no physical or mental impairments. “It was clear to me from the beginning that I wouldn't have another stroke: I was sure during the acute treatment that it wouldn't happen again,” he says.

Stéphane only found out later how lucky he had been: Of the more than 12 million people who suffer a stroke every year, 6.5 million die and many are left with a permanent disability [2]. However, even those who have a good outcome are at risk: Up to 20 percent of people who have a stroke once suffer another within five years [1]. 

Stéphane's doctors gave him a chance to escape this fate, because they found the cause of his cerebral infarction – a patent foramen ovale (PFO). Many people live with this condition undiagnosed and symptom-free, but it can lead to a stroke. “Even though my father was a cardiologist, I never knew about this hole. It was also never detected during examinations in adulthood. It was only after my stroke that the doctors specifically looked for the cause and found the opening,” says Stéphane.

It was immediately clear to Stéphane that he would have heart surgery. The minimally invasive operation gave him more certainty that no blood clots would be able to travel to his brain and cause another stroke. “I was lucky once. I didn't want to take any chances.”

A stroke can have many different causes and must therefore be treated on a case-by-case basis. If the underlying condition is not treated, a relapse is very likely [1]. Modifiable risk factors for stroke include high blood pressure, diabetes, obesity, smoking, and high cholesterol – and especially a combination of several of these factors. The most common cause of stroke is atrial fibrillation. This can cause small blood clots to form in the heart [4], which can then travel to the brain and block blood flow. Stéphane also had small blood clots migrating to his brain as a result of his PFO (see info box).

“If you've had a stroke due to for example carotid artery stenosis, that doesn't mean it has to be the sole trigger for a second stroke in the future. It could be that you have in addition an underlying heart disease, and the future stroke results from that,” says Professor Mira Katan, MD, head of the Stroke Unit and deputy head of Acute Neurology at University Hospital Basel. 

“We have to do a very thorough evaluation looking for any possible underlying disease to get a complete picture of our patients in order to be able to prevent another stroke,” says Katan. In Stéphane's case, acute care went very well, and the search for the underlying cause was also started.

“Secondary stroke prophylaxis begins the day after the stroke. It has to be so fast because there is a risk of early relapse, especially in mild strokes,” explains Professor Carlos Molina, MD, head of the Stroke Research Group and the Neurology Section at Vall d'Hebron University Hospital in Barcelona. “These cases seem like they're not that serious, but they have a high risk of recurrence. In some cases, the risk can be as high as 60 percent in the first week.”

Stroke Centers, such as the one at the University Hospital Basel, have integrated standardized diagnostics into their procedures for acute stroke patients to in a first step differentiate ischemic from hemorrhagic strokes immediately as acute treatment is fundamentally different but clinical presentation can be the same. “The gold standard for the exclusion of a hemorrhagic stroke is at most institutions a CT scan. If we can't identify a hemorrhage we do angio-CT imaging, which we use to look at the vessels at the same time to identify for example Large Vessel Occlusions. And depending on some other information, we'll also do perfusion imaging,” says Katan. 

Distinguishing between ischemic stroke and hemorrhagic stroke (see info box) using CT scans is straightforward for experienced physicians, but they must also gather additional information to guide acute and long-term therapy. 

Then there are patients with stroke-like symptoms, but imaging identifies a different cause. “It's important to differentiate between all of these because you treat the causes differently. Also, ‘time is brain,’ which means we have to act quickly. About 1.9 million neurons die on average in just one minute after a stroke. So time really does matter,“ says Katan.

After acute treatment and identification of the cause, patients begin receiving long-term therapy. This can present significant challenges for patients and medical staff, especially with regard to the risk of secondary stroke. Molina and Katan see a great opportunity in reliable follow-up care: “The problem with a stroke is that it's like a car accident. You want to forget it, you don't want to have to remember. This is typical human behavior,” explains Molina. 

“A month after the stroke, patients may simply stop taking the medication because they feel healthy again. They think they’re fine. But they don't know that they have a ticking bomb inside them. If they don't take the medication, it's going to come back.” If patients reliably follow their therapy, take their medication, and have regular checks-ups, they are in a good position. This episode of our podcast explores how to achieve this in the future.

Stéphane had an inner conviction that he would never have a stroke again. But he doesn't leave it up to chance: He now lives more consciously and listens to his body, pausing when he feels exhausted. He does a lot of sports and goes for check-ups. Nevertheless, the topic of stroke is always there:  “Whenever I see an ambulance driving through the city with blue lights, I think it's someone who's had a stroke. It won't let me go.”