CED Talks challenge conventional thinking
Three speakers posed powerful propositions covering diverse stroke subjects.
CED Talks (Cerebrovascular Education and Discovery) on Wednesday featured three speakers who posed powerful propositions covering diverse subjects. They ranged from atrial fibrillation versus atrial cardiopathy, understanding cerebrovascular hemorrhages in pregnancy and acute ischemic stroke treatment recommendations.
Embolic Stroke of Undetermined Source: At the Intersection of Heart and Brain
Mitchell S.V. Elkind, MD, MS, FAAN, FAHA
AHA President Mitchell S.V. Elkind kicked off the talks with “Embolic Stroke of Undetermined Source: At the Intersection of Heart and Brain.”
“The main idea I want to try to get across to you is that atrial fibrillation could just be an aisle marker of risk. AF comes and goes; we chase after it. But there may be a better way to capture that risk information without going through all of the activity of finding the AF itself,” he said.
Elkind laid out his case by exploring atrial fibrillation and atrial cardiopathy as indicators of stroke.
“There is certainly evidence that the more AF you have, the higher the AF burden; in other words, the more likely you are to have a stroke. But where is that lower cutoff where you do not have to worry? That remains uncertain,” he said.
Elkind pointed to evidence that suggests the longer you monitor patients, the more likely you are to detect AF.
“If we have to monitor people for months or years after they have a stroke in order to detect they have AF, then how valuable is that? A patient has a stroke today, you monitor them, and six months later, you see 30 seconds of AF, do we then say, ‘Now I know what caused the stroke six months ago’? There seems to be something counterintuitive about that.
“To my way of thinking and that of my colleagues, we would like to think of the AF as being indicative of underlying atrial disease or an atrial cardiopathy rather than the direct cause of stroke,” he said.
Cardiologists recognize atrial cardiopathy as being part of the AF process and being present in patients with AF. But we as neurologists are focused primarily on the possibility of atrial cardiopathy even in the absence of AF, and certainly in the absence of diagnosed AF, he said.
In thinking about how vascular risk factors ultimately can lead to stroke, he said we usually think they go through lots of different non-atrial stroke mechanisms. Vascular risk factors can also cause an abnormal atrial substrate that can lead to AF and cause stroke, he said.
Elkind then asked, what if that abnormal atrial substrate can lead to stroke directly? “That is essentially what atrial cardiopathy is. It excludes the need to go through this pathway of the AF.”
He identified biomarkers of atrial cardiopathy, including AF, other arrhythmias, enlarged left atrium, P-wave abnormalities and genetic markers of AF.
“We would like to think that any of these can be used to identify patients who might be at elevated risk. This matters because potentially we can intervene with anticoagulation to try to reduce the risk of stroke in these patients.”
He said that is the focus of the ARCADIA trial, which is testing whether anticoagulation works in people who have these atrial cardiopathy biomarkers, but do not have AF.
Neuro-Obstetrics: Partnering to Prevent Maternal Morbidity and Mortality
Eliza C. Miller, MD, MS
“The prevailing myth out there is that when women have strokes during pregnancy or post-partum, it is because of the hypercoagulable state of pregnancy,” said, Eliza C. Miller, MD. “That is not what we were actually seeing. What I was seeing much more were these big intracerebral hemorrhages.
“Maternal mortality in the United States is a disgrace. We have the worst maternal mortality in any developed country,” she said. “For Black women, the mortality rate is triple the rate that it is for White women.”
She said stroke mortality is under-recognized and mischaracterized. Pointing to data from the CDC, she said 7.7% of maternal mortality is attributed to cerebrovascular accidents, but another 6.9% are attributed to hypertensive disorders of pregnancy.
Hypertensive disorders affect about 10% of all pregnancies and include gestational hypertension, preeclampsia, the hemolysis, elevated liver enzymes, low platelet count (HELLP) syndrome, eclampsia and more.
“If you go back to OB literature from 50 years ago, you will find that when they used to do big autopsy series, and they looked at women who had died of what they used to call toxemia and now refer to as preeclampsia, they found that one-third died from intracerebral hemorrhage and another large percentage died of cerebral edema complications.
Miller said preeclampsia, known as the disease of theories because it is still so mysterious, and maternal stroke need more discussion and study.
“This is what I call the role of neuro-obstetrics. I see it as a whole field of academic and clinical medicine that is going to involve more collaborative clinical care between neurologists and obstetricians,” she said.
Clear Thinking About Acute Ischemic Stroke Treatment
Michael D. Hill, MD, MSc
University of Calgary
Acute stroke treatment boils down to speed and imaging judgment, according to Michael D. Hill, MD, MSc. He tracked the evolution of acute stroke treatment over the last 30 years, and said how amazing today’s treatments are, including strides brought about primarily by imaging.
He recalled enrolling patients in early trials of mechanical retrieval and recanalization of stroke clots using embolectomy (MR RESCUE) and the amount of time it took to do everything prior to actually proceeding with the procedure.
“One of the lessons we didn’t take into the early intervention trials was the focus on speed. That has now evolved,” he said. “That was certainly one of the key reasons the interventional trials worked. We got people treated really quickly.”
He identified two key elements to choosing patients: clinical judgment and imaging. He said clinicians make decisions based on the patient’s age, fragility and pre-morbid status.
For imaging, “we have to know what we are actually imaging. We sometimes conflate tissue and blood flow and think those things measure the same thing. We don’t perhaps spend enough time thinking about the details of imaging acquisition and balancing the processing time of imaging and the decline in treatment time that it takes simply because speed is so important.”
“You have to treat fast: Door-to-needle time under 30 minutes. We looked at data from the control group in the highly effective reperfusion using multiple endovascular devices (HERMES) analysis, if you treat a patient in under 30 minutes, compared to treating a patient in 30 to 60 minutes, from door to needle, one extra patient in five will have a good outcome,” he said.
Ultimately, he advised “Move quickly. Be simple. Give it the juice. Get the vessel open.”