By: Linxin Li, Simona Sacco
twitter: #GSSW @Simona_Sacco_
ESO Garmisch Stroke Science Workshop 2021
Session 6: Stroke in the Post-Pandemic Era
It was great to see a strong participation in this highly topical session on stroke in the COVID-19 era.
Our keynote speaker Georgios Tsivgoulis gave a very comprehensive overview of different aspects of cerebrovascular disease in patients with COVID-19. In contrast to the initial report of a high prevalence of 5% from Wuhan, subsequent studies showed that prevalence of stroke was around 1-2% with ischaemic stroke being most common. Of all the ischaemic stroke subtypes, there seemed to be a considerably high rate of large vessel occlusion and a high proportion of cryptogenic stroke. Mechanisms behind the link of COVID-19 and cerebrovascular disease are complex but evidence from self-controlled case series and matched cohort study showed a convincing temporal relationship suggesting that the association might be causal, which also highlighted the importance of vaccination. One other important issue raised was the impact of COVID-19 on stroke care across the world. The pandemic saw a marked decline of acute stroke hospitalisation and the use of acute stroke treatment. Whilst the reasons are multifactorial including both patient behaviour change and service provision adaptation, many important lessons have been learnt.
It was also wonderful to have our cardiology colleagues in the session. Ignatios Ikonomidis from Greece presented very intriguing data on cardiac complications of COVID-19. He showed that whilst some cardiovascular manifestations of COVID-19, such as myocardial infarction, could be clearly identified and treated, they can also present in the form of myocardial injury and subsequent ventricular dysfunction. What is perhaps more concerning is that such vascular and cardiac damage was not only seen acutely during the COVID-19 infection but was also evident 1 year after. As for some practical points, echocardiography remains an invaluable tool and can be used in guiding management of critically ill patients. More importantly, given some of the observed longer-term damage, follow-up echocardiography should be considered for guiding return to exercise for athletes.
The next talk was by Patrik Michel from Switzerland on anticoagulation in patients with COVID-19. Patrik discussed relative risk of stroke and venous thromboembolism (VTE) with COVID and showed that whilst there was a three-fold increase of VTE in COVID patients admitted to intensive care, no significant increase was observed for VTE in patients who were hospitalised without admission to intensive care. On the other hand, risk of ischaemic stroke risk and cerebral venous sinus thrombosis (CVST) was moderately increased with COVID-19 especially in those hospitalised. Proposed mechanisms behind this risk included an “inflammatory soup” related with hypercoagulability and inflammation. The rationale behind anticoagulation in patients with COVID-19 included improving outcome and stroke prevention. Unfortunately randomised trials showed no or little effect but increased risks of haemorrhage with intensive VTE-prophylaxis in COVID patients generally. For those patients who also suffered from stroke, usual ESO guideline should be followed. Similarly, there is little evidence at the moment to suggest anticoagulation or antiplatelet treatment would be helpful for primary prevention of stroke in patients with COVID-19 and the recommendation remain also to follow current ESO guidelines after COVID-19 related stroke.
Of course one other important aspect of the pandemic era is COVID-19 vaccine. Diana Aguiar de Sousa from Portugal gave a very elegant talk on vaccine-induced thrombotic thrombocytopenia. They should first be congratulated on the very timely global collaboration in this emerging field. Definition for any new syndrome can be challenging and we learnt that Vaccine Induced Immune Thrombotic Thrombocytopenia (VITT) or Thrombosis with Thrombocytopenia Syndrome (TTS) are the two currently widely accepted terminology. Clinical presentation of VITT has a rather distinctive profile with most of the patients under the age of 50 years and half also presented with CVST. Fantastic data from the International Cerebral Venous Thrombosis Consortium were also presented. It was clear that CVST associated with VITT/TTS was significantly more severe with poorer outcome compared with CVST without VITT/TTS. Although the absolute incidence of CVST in this context was still rare, most of the risk was driven by the higher absolute risk of CVST after ChAdOx1 nCoV-19, especially among adults aged 18-24 years. Slightly reassuringly, there may be an encouragingly lower risk in Asian countries, where ChAdOx1 nCoV-19 is currently widely used. Finally very interestingly, new data comparing heparin-induced thrombocytopenia vs. VITT/TTS cases suggested that pathophysiological mechanisms other than platelet factor 4 antibodies may contribute to the high rate of CVST seen in patients with VITT/TTS, which may potentially impact future management of these patients. There are of course still many unanswered questions and we look forward to more development with the continued international effort in tackling these questions.
Whilst the session ended after the scheduled time, heated discussion continued. I’m sure more questions and discussion will emerge whilst we are still combating the battle against COVID-19. Hopefully one day when we are finally out of the fog, we will look back and say, those were days that we stood together and it was an invaluable adventure.