Large Vessel Occlusions By Free Floating Thrombi in Strokes During the COVID-19 pandemic- A Single Center Observational Study

Background: An increased incidence of systemic macrothrombotic phenomena such as strokes has been observed in moderate and severe COVID. However, strokes have also been increasingly observed in mild COVID, post COVID, or without obvious COVID illness. Objective: To share our experience with a specific stroke type noted during the COVID pandemic period. Materials and Methods: A single-center observational study was conducted in Western India from January to December 2020, and data regarding stroke patients admitted under Neurology services were noted. Clinical, laboratory, and radiological characteristics of strokes and subtypes were documented. Results: A total of 238 stroke patients were admitted in 2020, 76.5% during the COVID pandemic period. Among 153 ischemic strokes, 16.3% and 56.2% had large vessel occlusion (LVO) in pre-COVID and COVID pandemic period, respectively. Of all ischemic strokes, 20.9% (18 patients) and 12% (3 patients) had free floating thrombus (FFT) in the COVID versus pre-COVID period, respectively. Only 44.4% of all FFT patients could be proven SARS-CoV-2 RT-PCR positive while 50% were COVID suspect with surrogate markers of heightened inflammation at time of stroke. All patients were given anticoagulation and average mRS at discharge was 3.1 (range: 1-6) and 1.84 (range: 0-4) at 3-month follow-up in survivors. Conclusions: This study highlights the presence of FFT causing LVO as a new stroke subtype during the COVID-19 pandemic. With renewed and steeper spike in COVID-19 cases, especially new variants, the resurgence of this stroke subtype needs to be actively explored early in the course of illness to reduce morbidity and mortality.