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Risk of thromboembolic events as measured by endothelial function...

Risk of thromboembolic events as measured by endothelial function is not elevated in total knee replacement patients with history of COVID disease

Kethy Jules-Elysee, Carola Hanreich, Friedrich Boettner, Anna Jungwirth-Weinberger, Alison Zhao, Robyn Schultz, Ilya Bendich, Lisa Mandl

Dept. of Anesthesiology, Critical Care & Pain Management, Adult Reconstruction and Joint Replacement, Rheumatology, Hospital for Special Surgery, New York, NY 10021 Dept. of Orthopedic Surgery, Washington University School of Medicine, Saint Louis, MO 63110


Endothelial injury as per Virchow’s triad plays a major role in the formation of postoperative thrombosis. Endothelial dysfunction has been described in patients with thromboembolic events., and also in patients with active COVID infection. It is not known whether this predisposition to endothelial dysfunction (ED) persists upon resolution of active COVID infection implying possible need for higher level of thromboprophylaxis especially during the postoperative periods. Endothelial function (EF) can be measured non-invasively using a reactive hyperemia procedure such as offered by the VENDYS-II device. Since thromboembolic events also remain an issue following total knee replacement (TKR) surgery (2), this study aims to compare EF in SARSCoV-2 IgG-positive vs SARS-CoV-2 IgG-negative TKR patients, in order to evaluate a possible need for more aggressive anticoagulation in TKR patients with history of COVID disease


53 SARS-CoV-2 IgG-positive (case group) and 48 SARS-CoV-2 IgG-negative (control group) patients that received a primary TKR for knee osteoarthritis were consecutively recruited within a prospective matched cohort study. Patients were matched based on age, BMI and surgeon’s volume. EF was assessed twice using the VENDYS-II device; once before surgery (DOS) and once on postoperative day 1 (POD 1). EF was quantified by the vascular reactivity index (VRI) numerically ranging between 0-3.5 (0=poor, 3.5=excellent). Data analysis was performed using t-test and a multivariable linear regression model was used to determine factors associated with postoperative VRI.


Case and control patients did not significantly differ in age, body mass index or co-morbidities (hypertension, diabetes mellitus, congestive heart failure, pulmonary disease, stroke, angina pectoris and malignant disease). (Table 1) Mean pre- and postoperative VRI did not significantly differ between SARS-CoV-2-IgG-positive and SARS-CoV-2-IgG negative patients. There was also no significant change in the VRI from pre- to postoperative. (Table 1) Duration of COVID infection (p=0.44), time since COVID infection (p=0.59) and severity of COVID infection (p=0.17) did not correlate with postoperative VRI. Increased postoperative VRI was not associated with increased length of hospital stay (p=0.15).


This study demonstrates no significant difference in endothelial function between SARS-CoV-2 IgG-positive and SARS-CoV-2 IgG-negative patients either before or after TKR surgery and no association with severity and time since COVID infection. In view of the lack of difference in endothelial function, more aggressive DVT prophylaxis is not needed in TKR patients with history of COVID disease who have fully recovered from their illness


1. Mehta P, McAuley DF, Brown M, Sanchez E, Tattersall RS, Manson JJ. COVID-19: consider cytokine storm syndromes and immunosuppression. Lancet (London, England). 2020;395(10229):1033-4. 2. Santana DC, Emara AK, Orr MN, Klika AK, Higuera CA, Krebs VE, et al. An Update on Venous Thromboembolism Rates and Prophylaxis in Hip and Knee Arthroplasty in 2020. Medicina (Kaunas, Lithuania). 2020;56(9)


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