Acute limb ischemia (ALI) can occur with or without atherosclerotic disease and portends a worse prognosis in patients with COVID-19. This risk persists after COVID-19 infection due to a lingering co-inflammatory state, and D-dimer may be a useful screening test in at-risk patients.
This is according to Max Wohlauer, MD, assistant professor of surgery at the University of Colorado Denver in Aurora, Colorado, who yesterday outlined a study assessing revascularization outcomes of ALI in COVID-19 patients. Wohlauer delivered the presentation during a Vascular and Endovascular Society (VESS) paper session at the 2022 Vascular Annual Meeting (VAM) in Boston (June 15–18) on behalf of first author Mahmood Kabeil, MD, senior author Robert F. Cuff, MD, assistant professor at Spectrum Health in Grand Rapids, Michigan, and on behalf of the Vascular Surgery COVID-19 Collaborative (VASCC).
“Coagulation and inflammation are linked, and a coagulopathy has been described with SARS and other respiratory viruses,” said Wohlauer, noting an increased D-dimer and other coagulation derangements in patients with COVID-19 infection. Giving additional context to his talk, the presenter noted that ALI is a risk factor for amputation and mortality in patients with COVID-19 infection, and that high D-dimer levels are associated with an increased risk of thrombosis in COVID-19 patients.
Outlining their methods for the study in an abstract, the researchers note that VASCC formed the basis of their analysis. A registry was developed in March 2020, they write, in order to assess the impact of COVID-19 infection on vascular surgery patients and practices. At VAM, Wohlauer reported an interim data analysis of 94 patients from 18 sites across five countries with the aim of providing an insight into revascularization strategies and outcomes for COVID-19-associated ALI.
The speaker noted that the 94 patients included in the interim analysis had a mean age of 64 years and that 37% were female. In this cohort, only 15% had a history of peripheral arterial disease (PAD), he added, and none had a prior hypercoagulable state. Only 2% had active cancer, and the rate of tobacco use was 21%.
Wohlauer was keen to emphasize the fact that 90% of the patients in the cohort had no prior history of vascular intervention. In addition, he detailed that ALI was the initial COVID-19 presentation in 21% of the cases, with the remaining 79% experiencing ALI a median of eight days after a positive COVID-19 test.
Giving further details on the patient cohort, the presenter noted that 53% were categorized as Rutherford 2b. He added that 89% of the thrombus was located in the lower extremity, 8% in the upper extremity, and 3% in the infrarenal aorta. Of the patients with lower extremity thrombus, he detailed that the majority was in the femoropopliteal region.
Reporting revascularization strategies in this cohort, Wohlauer detailed that 63% of patients underwent open revascularization, 16% endovascular, and 22% had no revascularization. In the patients who had no revascularization, he specified that 52% of the time it was because the limb was not salvageable. For others, it was related to the severity of COVID-19 pneumonia.
In terms of other outcomes, the presenter revealed that the mean hospital stay was 14.7 days, and mean intensive care unit (ICU) stay was 5.6 days. Thirteen percent required an amputation, 5.2% had a pulmonary embolism, 5.2% had a stroke, and 6.2% had sepsis. There was a 15.5% major adverse limb event rate in this cohort.
One of the key findings Wohlauer highlighted was a 31% in-hospital mortality rate. He also reported that, on the other end of the scale, 40% of patients had no major complications in hospital. Age was an independent risk factor for in-hospital mortality, he said, but was not a risk factor for major adverse limb events.
Wohlauer summarized that ALI is the initial COVID-19 symptom in up to one-third of patients, and that the overwhelming majority of patients with COVID-19 ALI have no prior vascular history, and that age is an independent risk factor for mortality, but not a risk factor for major adverse limb events. D-dimer, he informed the audience, may be a useful screening test in patients at risk for COVID-19-associated ALI.
He thanked all of the VASCC members who contributed data to this project, and acknowledged the VASCC Project 2 ALI Working Group. He mentioned that the study is actively recruiting patients and that the organization welcomes contributions.