The findings suggest that those with large-vessel-occlusion stroke and early cerebral veins may require aggressive blood pressure-lowering.
Presence of early cerebral veins after endovascular therapy for large-vessel-occlusion stroke is highly predictive of the risk of subsequent symptomatic parenchymal hemorrhage, according to the results of a study published online May 5, 2018, in Stroke..
In an interview with Neurovascular Exchange, senior study author Jeremy J. Heit, MD, PhD (Stanford University School of Medicine, CA), said identification of early cerebral veins could identify patients in need of early interventions to prevent reperfusion hemorrhage.
“When you take patients with large-vessel occlusion to the cath lab and do a thrombectomy procedure to open the artery, a successful procedure will maximize the chance that they will do well,” Heit said. “One bad outcome that could still occur after a successful procedure is a hemorrhagic complication. If we have a predictor that shows a patient is at higher risk for bleeding there are a few things we can start to do to minimize that risk.”
Heit and colleagues performed a retrospective study of 64 consecutive patients with acute ischemic stroke who underwent endovascular mechanical thrombectomy between January 2014 and March 2016. Of these, six patients (9.4%) developed symptomatic parenchymal hemorrhage. Patients with hemorrhage had much greater 90-day mortality than those who did not (83.3% vs 24.1%; P=0.01). There were no differences between groups for 90-day modified Rankin Scale scores or changes in National Institutes of Health Stroke Scale (NIHSS) scores from presentation to discharge.
Early cerebral vein was the strongest overall predictor of symptomatic parenchymal hemorrhage, more than twice as likely to predict risk as the next closest predictor, male sex.
The majority of patients with parenchymal hemorrhage had early cerebral veins compared with only a minority of patients with no hemorrhage (83.3% vs 17.2%; P < 0.001). Presence of early cerebral veins had a sensitivity and a specificity of 0.83 for predicting subsequent hemorrhage.
Although early cerebral veins were associated with 90-day mortality, lower platelet count and older age were both better predictors of 90-day mortality. To Neurovascular Exchange, Heit said an effect on outcomes like 90-day mortality may have been seen if the sample size had been larger.
According to Heit, there are other known imaging biomarkers of parenchymal hemorrhage, including large diffusion-weighted imaging volume, that can be discovered using pre- and posttreatment MRI and CT.
“The problem with the use of CT perfusion or MRI perfusion is that many of these techniques are not widely available. They require advanced postprocessing that is not widely available, and, often, are not available to be done in real time,” Heit said. “With our study, the biomarker is right there in front of you for everyone to see. It doesn’t require postprocessing or advanced imaging techniques.”
Heit said at his institution, patients with early cerebral veins undergo aggressive lowering of blood pressure.
“I can turn immediately to the anesthesiologist taking care of the patient and say, ‘Let’s get the BP down,’” Heit observed. In addition, patients may need to be placed on aspirin or something stronger to anticoagulate them, depending on the cause of the stroke, he added.
“If there is a patient with a high risk of bleeding in the brain, that is someone you would hold off on starting these medications to reduce the risk of having a bleeding event,” Heit said.
Validating these results is going to take more work, Heit noted. Parenchymal hemorrhage occurs in only 6% to 10% of patients in this population, and although that is a large number overall, it may only account for a few patients every year at a single center.
“We need to be pooling together to test this further,” Heit said. “It would be of interest if other people doing these procedures started to pay attention to [early cerebral veins] to validate our findings.”
Cartmell SCD, Ball RL, Kaimal R, et al. Early cerebral vein after endovascular ischemic stroke treatment predicts symptomatic reperfusion hemorrhage. Stroke. 2018;Epub ahead of print.
Heit reports no relevant conflicts of interest.