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Systemic thrombosis in a large cohort of COVID-19 patients despite thromboprophylaxis: A retrospective study
Nuria Muñoz-Rivas1, Ane Abad-Motos2, Beatriz Mestre-Gómez1
1Internal Medicine Department, Infanta Leonor University Hospital, Spain.
Insights
Despite thromboprophylaxis, Coronavirus disease-2019 (COVID-19) caused many thrombotic events, particularly arterial ones which predicted mortality. A severity-adjusted approach may reduce events and improve outcomes in COVID-19 patients.
Area of Science:
- Cardiology
- Hematology
- Infectious Diseases
Background:
- Assessing thrombotic event incidence in Coronavirus disease-2019 (COVID-19) is challenging, with varying reported rates.
- Optimal thromboprophylaxis strategies for COVID-19 patients remain unclear.
Purpose of the Study:
- To analyze characteristics of COVID-19 patients with thrombotic complications, including inflammatory and hemostatic parameters.
- To compare arterial versus venous thrombotic events and survival outcomes.
- To evaluate thromboprophylaxis compliance and the potential impact of a severity-adjusted protocol.
Main Methods:
- Retrospective study of 1127 COVID-19 patients admitted to a single hospital during the initial outbreak.
- Analysis of thrombotic events, patient characteristics, inflammatory markers (CRP), and coagulation status (ISTH DIC score).
- Multivariate analysis to identify predictors of mortality.
Main Results:
- 6.1% of patients (69/1127) experienced 80 thrombotic events; 90% received low-molecular-weight heparin.
- Arterial thrombotic events were associated with earlier onset and significantly higher mortality (OR=18).
- Higher initial ISTH DIC score and CRP levels were observed in non-survivors.
Conclusions:
- Coronavirus disease-2019 (COVID-19) is linked to diverse arterial and venous thrombotic events despite thromboprophylaxis.
- Arterial events in COVID-19 patients indicate a poor prognosis, with ISTH DIC score ≥3 as a potential mortality predictor.
- Severity-adjusted thromboprophylaxis may reduce thrombotic complications and mortality in COVID-19; further research via randomized controlled trials is needed.
Background:
Incidence of thrombotic events associated to Coronavirus disease-2019 (COVID-19) is difficult to assess and reported rates differ significantly. Optimal thromboprophylaxis is unclear.
Objectives:
We aimed to analyze the characteristics of patients with a confirmed thrombotic complication including inflammatory and hemostatic parameters, compare patients affected by arterial vs venous events and examine differences between survivors and non-survivors. We reviewed compliance with thromboprophylaxis and explored how the implementation of a severity-adjusted protocol could have influenced outcome.
Methods:
Single-cohort retrospective study of COVID-19 patients admitted, from March 3 to May 3 2020, to the Infanta Leonor University Hospital in Madrid, epicenter of the Spanish outbreak.
Results:
Among 1127 patients, 80 thrombotic events were diagnosed in 69 patients (6.1% of the entire cohort). Forty-three patients (62%) suffered venous thromboembolism, 18 (26%) arterial episodes and 6 (9%) concurrent venous and arterial thrombosis. Most patients (90%) with a confirmed thrombotic complication where under low-molecular-weight heparin treatment. Overt disseminated intravascular coagulation (DIC) was rare. Initial ISTH DIC score and pre-event CRP were significantly higher among non-survivors. In multivariate analysis, arterial localization was an independent predictor of mortality (OR = 18, 95% CI: 2.4-142, p < .05).
Conclusions:
Despite quasi-universal thromboprophylaxis, COVID-19 lead to a myriad of arterial and venous thrombotic events. Considering the subgroup of patients with thrombotic episodes, arterial events appeared earlier in the course of disease and conferred very poor prognosis, and an ISTH DIC score ≥ 3 at presentation was identified as a potential predictor of mortality. Severity-adjusted thromboprophylaxis seemed to decrease the number of events and could have influenced mortality. Randomized controlled trials are eagerly awaited.
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