How can Cardiologists and Neurologists Team Up to Better Diagnose Cryptogenic Stroke?
The vast majority of strokes—about 85 percent—are ischemic. Of these, up to a third are cryptogenic, or have no clear cause. Getting these strokes diagnosed quickly and accurately requires consistent and well-functioning teamwork between cardiologists, neurologists, and general practice physicians. Ahead of World Stroke Day, we took a look at how neurologists and cardiologists can better work together for timely diagnosis of previously cryptogenic strokes, and what role certain technologies like implantable cardiac monitors (ICMs) or smartwatches might have in the process.
Collaborating to Achieve Quick Diagnosis
A patient who experiences a stroke may end up first seeing a neurologist, who will consult a cardiologist if the reason for the stroke isn’t clear. With atrial fibrillation patients being five times as likely to experience a stroke with symptoms that are sometimes hard to notice, AF may well be one of the first suspected causes. But intermittent AF episodes can require significant time to diagnose, requiring an implantable cardiac monitor (ICM) that can take high-quality ECGs over a longer period of time. Furthermore, physicians may have to monitor and process quite a bit of data before finding the cause, making efficient workflows and early detection necessary for a timely diagnosis that can give a cryptogenic stroke patient their best chance. Telemonitoring can, however, help ease this burden.
An event recorder only makes sense with telemonitoring. Regular in-patient follow-up intervals aren’t sufficient because it’s impossible to react quickly enough when an event happens. Three months is too long—they require quick action.
“An event recorder only makes sense with telemonitoring,” says Dr. Eimo Martens, a cardiologist and Head of Device Therapy at the Technical University Hospital Rechts der Isar in Munich. “Regular in-patient follow-up intervals aren’t sufficient because it’s impossible to react quickly enough when an event happens. Three months is too long—they require quick action."
But even with modern technologies and improved workflows, combining the expertise of general practice, neurology, and cardiology—while also providing the capacity necessary for effective remote monitoring—can seem like an overwhelming task.
"The aftercare workload for stroke patients is enormous. Neither resident doctors nor cardiology clinics like ours can do it alone," says Dr. Martens. He says that while resident doctors remain best placed to care for and liaise with patients directly, they need the support of a well-functioning remote monitoring clinic to handle help pick out the right diagnosis from all the data.
“Resident doctors cannot guarantee the around the clock, 365 days a year monitoring required in cases like this, so they work with telemonitoring centers such as ours," says Dr. Martens. “Because monitoring alarms should be responded to within 24 to 48 hours.” He adds that signal quality is particularly important in deciding what ICM to use, both to recognize relevant events for diagnosis and to filter out irrelevant ones to help manage clinic capacity and workload.
I would like to see even more cooperation across the disciplines, and between resident doctors and clinics, in order to achieve the best results for patients.
Close cooperation between disciplines is essential for successful stroke care
Dr. Silke Wunderlich, neurologist and Head of the Stroke Unit at the clinic Rechts der Isar in Munich, says one of the first things her team will want to know is whether a cryptogenic stroke patient has paroxysmal AF or not, and enlists the cardiology team to recommend the right ICM. She says while there’s a great deal of mutual trust between departments, there’s always room for improvement. "I would like to see even more cooperation across the disciplines, and between resident doctors and clinics, in order to achieve the best results for patients," she says.
I am sceptical about whether smartwatches will work for older stroke patients. After all, the devices have to be worn correctly and alarms need to be responded to.
Could Smartwatches be an alternative to ICMs for Cryptogenic Stroke?
Given the workload requirements for accurately diagnosing cryptogenic stroke, could certain consumer grade products be alternative or compliment to ICMs requiring constant telemonitoring capacity?
Dr. Wunderlich and Dr. Martens are planning a study to find out, involving around 400 patients across ten German centers, starting in 2022. “We’re going for an intra-individual comparison,” Dr. Wunderlich says. “So, the same patients will wear a smartwatch and have an ICM as well.”
For now, though they’re cautious on wearables as opposed to ICMs.
“I am sceptical about whether smartwatches will work for older stroke patients with neurological deficits. After all, the devices have to be worn correctly and alarms need to be responded to," says Dr. Wunderlich.
“There is no smartwatch that offers continuous ECG monitoring, unlike an event recorder. These ICMs monitor the heartbeat continuously, detect atrial fibrillation, record the event, and alert us. The smartwatch, on the other hand, records a so-called PPG signal and uses it to create a pulse curve," says Dr. Martens. “Smart wearables are still a long way from replacing medical devices. The signal quality and the analysing algorithms cannot yet keep up in clinical practice."
A Physician’s Wishlist for Better Patient Care
Although remote monitoring workflows are complex and quick diagnosis of cryptogenic stroke isn’t always easy, a few measures can help cardiologists and neurologists work together better.
"If I could make a wish, I would ask for standardized workflows and reimbursement for remote monitoring systems,” states Dr. Martens.
"More dialogue between the disciplines would help us to care for cryptogenic stroke patients more effectively," adds Dr. Wunderlich.
To find out more about how clinicians can operate a remote monitoring clinic that can manage the capacity required for cardiovascular events like cryptogenic stroke, check out Matt Swift’s piece on a case from his clinic. To read more about what role ICMs can play in stroke prevention, check out our piece on screening.