A conversation with Diogo Haussen, MD, Assistant Professor of Neurology, Emory School of Medicine/Grady Memorial Hospital, and Yasir Saleem, MD, Assistant Professor of Neurology, Baylor College of Medicine, on the approach to patients with large vessel occlusion (LVO) and mild symptoms.
Interviewed by Jennifer Harris, MD, stroke fellow, Columbia University, and Rachel Forman, MD, stroke fellow, Massachusetts General Hospital.
They will be discussing the article “Acute Neurological Deterioration in Large Vessel Occlusions and Mild Symptoms Managed Medically,” published in the May 2020 issue of Stroke.
Drs. Harris and Forman: Thank you for taking the time to speak with us on this important topic.
Drs. Haussen and Saleem: Thank you for reaching out. It is a pleasure interacting with you.
Drs. Harris and Forman: As stroke fellows, we run into this scenario from time to time, and it is often a challenging decision that generates good discussion. What was the background for you in wanting to study this specific topic?
Drs. Haussen and Saleem: A common reason for neurological deterioration in patients presenting with mild strokes is the underlying presence of a large vessel occlusion. Importantly, neurological worsening in this setting has been associated with worse clinical outcomes. However, not all individuals with large vessel occlusion and mild presentation end up worsening. We have observed, in our original experience (Haussen DC et al. JNIS 2017 Oct;9(10):917-921), that >40% of patients with LVO medically managed had some degree of neurological deterioration. We wanted to evaluate the potential variables that could potentially predict neurological worsening within patients presenting with minor stroke symptoms and large vessel occlusion.
Drs. Harris and Forman: What is your team’s approach for patients in this category as far as their medical management and ensuring this is optimized (i.e., blood pressure parameters, frequency/duration of neurological monitoring)? Do you include patients with more distal (M3 or PCA) clots in this same category?
Drs. Haussen and Saleem: Although the evidence is lacking, we generally perform a heads-up test in order to stress collaterals and evaluate for acute neurological deterioration in patients with mild presentations. We consider important to optimize the hydration status and to allow the blood pressure to autoregulate. Considering we have observed that patients with large vessel occlusion and mild stroke deteriorate early, it is critical to have patients carefully monitored for the first multiple hours from symptom onset. It is possible that more proximal occlusions (e.g., MCA M1 as compared to MCA M3) may carry a higher risk of deterioration; however, this is anecdotal.
Drs. Harris and Forman: It was interesting to note that there were no clinical or radiological predictors of neurological deterioration on multivariate analysis. From a personal experience, do certain features (either clinically or radiographically) stand out to you where you would be on higher alert in a specific patient?
Drs. Haussen and Saleem: Despite not identifying any predictors, we know that a large proportion of patients deteriorate early. Therefore, all need to be monitored closely. It is relatively clear that rapid improvement may predict subsequent deterioration; therefore, patients that improve and still have an occlusion are at higher risk. Individuals with very high blood pressure levels in order to maintain collaterals could be at risk of failure. In addition to the established factors influencing leptomeningeal collateral strength, large areas of perfusion defect on perfusion imaging, more proximal occlusions, and embolic occlusions (instead of in-situ atherosclerotic thrombosis that generally have better developed collaterals) could be suggested as potential factors influencing the risk of neurological worsening.
Drs. Harris and Forman: In the study, you found that 19.7% of patients had >4 points deterioration on NIHSS and that this occurred pretty rapidly from arrival time (median of 3.6 hours). Did these numbers surprise you, or is it similar to what you have observed in clinical practice?
Drs. Haussen and Saleem: We used a relatively high threshold for defining deterioration, and therefore believe that this number is in line with previous studies and with our experience.
Drs. Harris and Forman: Did the study change your approach to this patient population, and if so, how did it change? Finally, what are the main takeaways you want the readers to have, and what are the next steps with future studies?
Drs. Haussen and Saleem: Significant acute neurological deterioration was observed in a significant proportion of patients (~1/5) with large vessel occlusion and mild symptoms, occurred very early in the hospital course, and impacted functional outcomes. Rescue thrombectomy was associated with improved clinical outcomes and should be considered emergently in patients that worsen during medical management. Considering that we could not identify potential clinical, laboratorial or radiological predictors, it becomes even more evident that controlled studies are needed.
Drs. Harris and Forman: Thank you very much.