Rates of Thromboembolic Complications High in COVID-19+ ICU Patients

Patients in the intensive care unit (ICU) for COVID-19 had high rates of major arterial or venous thromboembolism (VTE), major adverse cardiovascular events, and symptomatic VTE, according to data from the CORONA-VTE study presented at the American Heart Association Scientific Sessions 2020.

“Systemic inflammation, endothelial injury, immobility, and hypercoagulability are thought to promote thromboembolic complications especially in the critical care setting,” explained study presenter Gregory Piazza, MD, MS, director of the vascular medicine section at Brigham and Women’s Hospital. “Quantifying the risk of cardiovascular complications in the heterogeneous population of patients with COVID-19 has been hampered by limited sample size, restriction of focus to the ICU setting, variable outcome definitions, and differing thromboprophylaxis patterns.”

To learn more, Dr. Piazza and colleagues analyzed 1,114 patients diagnosed with COVID-19 in their healthcare network. Patients were analyzed by site of care: ICU (n=170), hospitalized non-ICU (n=229), and outpatient setting (n=715). The cohort was 22.3% Hispanic/Latinx and 44.2% non-white. The primary study outcome was a composite of adjudicated major arterial or venous thromboembolism at 30 days.

It was common for patients to have cardiovascular risk factors including hypertension (35.8%), hyperlipidemia (28.6%) and diabetes (18.0%). The median length of stay for the ICU cohort was 16 days and was 5 days for the admitted non-ICU cohort. Thirty percent of ICU patients were still hospitalized by 30 days. The majority (89.4%) of patients in the ICU cohort and the non-ICU hospitalized cohort (84.7%) were prescribed prophylactic anticoagulation.

“Major arterial or venous thromboembolism, major adverse cardiovascular events, and symptomatic VTE occurred with high frequency over 30 days in ICU patients with COVID-19 despite nearly 90% thromboprophylaxis,” Dr. Piazza said.

The incidence of major arterial or VTE (35.3%), major cardiovascular adverse events (45.9%) and symptomatic venous thromboembolism (27.0%) were highest in the ICU cohort, followed by the hospitalized non-ICU cohort (2.6%, 6.1%, 2.2%, respectively).

“Interestingly our outpatients did not have any observed major adverse events,” Dr. Piazza said.

The researchers analyzed time from COVID-19 PCR diagnosis to major arterial and VTE. The risk for major thromboembolic events and symptomatic VTE seemed to really increase for the ICU cohort at around 5 days, Dr. Piazza noted. For major cardiovascular events, the risk appeared to increase earlier in the ICU stay.

Multivariable analyses showed that in the ICU cohort there was a nearly sevenfold increase in the odds of major arterial or VTE events associated with adult respiratory distress syndrome (ARDS; adjusted odds ratio [OR]=6.69; 95% CI, 1.85 to 24.14). There was also almost a sixfold increase in the odds of major cardiovascular events associated with ARDS (adjusted OR=5.79; 95% CI, 2.01 to 16.69) and a twofold increase related to male gender (adjusted OR=2.07; 95% CI, 1.02 to 3.64). There was a “staggering” 24-fold increased risk for symptomatic VTE associated with ARDS (adjusted OR=24.39; 95% CI, 1.50 to 398.00).

Dr. Piazza noted that catheter- and device-related deep vein thrombosis comprised a large proportion of VTE in the ICU cohort and may have inflated the study’s estimate. Additionally, although 30-day follow-up data were available for 96% of patients, the researchers were unable to obtain follow-up data for 40 outpatients and, therefore, they were likely to have underestimated 30-day outcomes in this cohort.