Outcomes of Cerebral Venous Thrombosis due to Vaccine-Induced Immune Thrombotic Thrombocytopenia After the Acute Phase

Abstract

Background: Cerebral venous thrombosis (CVT) due to vaccine-induced immune thrombotic thrombocytopenia (VITT) is a severe condition, with high in-hospital mortality rates. Here, we report clinical outcomes of patients with CVT-VITT after SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) vaccination who survived initial hospitalization. Methods: We used data from an international registry of patients who developed CVT within 28 days of SARS-CoV-2 vaccination, collected until February 10, 2022. VITT diagnosis was classified based on the Pavord criteria. Outcomes were mortality, functional independence (modified Rankin Scale score 0–2), VITT relapse, new thrombosis, and bleeding events (all after discharge from initial hospitalization). Results: Of 107 CVT-VITT cases, 43 (40%) died during initial hospitalization. Of the remaining 64 patients, follow-up data were available for 60 (94%) patients (37 definite VITT, 9 probable VITT, and 14 possible VITT). Median age was 40 years and 45/60 (75%) patients were women. Median follow-up time was 150 days (interquartile range, 94–194). Two patients died during follow-up (3% [95% CI, 1%–11%). Functional independence was achieved by 53/60 (88% [95% CI, 78%–94%]) patients. No new venous or arterial thrombotic events were reported. One patient developed a major bleeding during follow-up (fatal intracerebral bleed). Conclusions: In contrast to the high mortality of CVT-VITT in the acute phase, mortality among patients who survived the initial hospitalization was low, new thrombotic events did not occur, and bleeding events were rare. Approximately 9 out of 10 CVT-VITT patients who survived the acute phase were functionally independent at follow-up.

Endovascular treatment of cerebral sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia

“…Almost 90% achieved functional independence, as was reported for CVST-VITT irrespective of EVT. 20 Nevertheless, half of the CVST-VITT patients treated with EVT died during the initial admission, which is similar to the mortality in patients without EVT, but significantly higher than in the EVT studies of CVST unrelated to vaccination (12%). 4,6 This is most likely due to the greater severity of CVST-VITT in general.…”

“…2 Compared to previous anecdotal reports, the rates of technical success, complications and favorable outcomes were similar, while mortality was higher in our cohort (50% vs 27%, Supplemental Table ). However, the mortality rate of 27% is lower than in CVST-VITT in general (40%) 20 and might be subject to reporting bias, as it is based on single cases and small cohorts up to n = 6. If not available carried forward from admission (n = 3 for hemorrhagic lesion, D-Dimer and fibrinogen, n = 5 for platelet count).…”

Decompressive surgery in cerebral venous sinus thrombosis due to vaccine‐induced immune thrombotic thrombocytopenia

“…This proportion is in line with our previous report on outcomes of CVST-VITT patients in the acute phase of their presentation. At the 5-month follow-up, almost 90% had regained functional independence [10,22,23]. Nevertheless, due to the limited size of this substudy cohort, these numbers should be interpreted with caution.…”

Unique features of vaccine-induced immune thrombotic thrombocytopenia; a new anti-platelet factor 4 antibody-mediated disorder

“…There are varying reports of whether females are more at risk for CVST in the context of VITT. In an observational study ( n = 60) of CVST occurring within 28 SARS-CoV-2 vaccination, 75% were female [ 42 ]. A female predominance (81%) was also reported in an international registry of CVST within 28 days of SARS-CoV-2 vaccination [ 43 ].…”

“…Another study of VITT-associated CVST ( n = 78) reported an in-hospital mortality rate of 47%, compared with 3.9% for CVST in historical, non-VITT controls [ 43 ]. The highest risk of death is during the acute phase of CVST, with a lower frequency of adverse outcomes beyond the acute phase [ 42 ]. CVST is often associated with other thromboembolic events in up to 36% of VITT patients compared to 4.9% in non-VITT controls [ 43 ].…”