Trial results shed light on tool for assessing VTE risk, routine anticoagulation for non-hospitalized COVID patients, and clinical outcomes of open vs. endovascular surgery for advanced PAD
Investigators in four trials revealed findings to impact the treatment of hospitalized patients at risk for venous thromboembolism (VTE), non-hospitalized patients with COVID-19 and chronic limb threatening ischemia during “Preventing Limb Loss Through Vascular Interventions and Venous Therapies” Late-Breaking Science session on Monday. They found:
- A validated risk assessment tool successfully identified hospitalized patients requiring pharmacologic prophylaxis.
- COVID patients don’t benefit from routine anticoagulation therapy.
- There’s a continued role for open bypass revascularization for patients with chronic limb threatening ischemia.
- Both open and endovascular surgery improve quality of life for patients with chronic limb threatening ischemia.
Universal VTE risk assessment tool is associated with an increase in appropriate thromboprophylaxis and decrease in major thromboembolic events
Use of a universal EHR-integrated clinical decision support tool using a validated venous thromboembolism (VTE) risk model, the IMPROVE-DD, significantly increased rates of in-hospital appropriate thromboprophylaxis, including at-discharge extended thromboprophylaxis, and significantly reduced major thromboembolic events without an increase in major bleeding at 30 days post-discharge, compared to usual medical care, according to Universal Electronic Health Record Clinical Decision Support for Prevention of Thromboembolism in Hospitalized Medically Ill Patients: the IMPROVE-DD VTE Cluster Randomized Trial.
The large cluster randomized trial enrolled 10,699 patients from four academic tertiary hospitals from Dec. 21, 2020, to Jan. 21, 2022; two clusters received usual medical care and two clusters incorporated the IMPROVE-DD VTE score. The tool included seven clinical risk factors including a laboratory factor of elevated D-dimer to identify patients into three thrombotic risk categories: (0-1) low risk, (2-3) moderate risk or (4-12) high risk. Hospitalized patients with an IMPROVE-DD score of ≥2 received in-hospital unfractionated heparin or low molecular weight heparin. At discharge, patients with a score of ≥4 received rivaroxaban for 30 days post-discharge as per the order entry.
Use of the tool resulted in an approximate 50% increase in thromboprophylaxis and an approximate two-fold increase in appropriate, at-discharge extended thromboprophylaxis (7.5% in the control group versus 13.6% in the intervention arm), meeting its primary outcome.
In a secondary analysis, a 20% reduction in rates of VTE, a 65% reduction in arterial thromboembolism and a 29% reduction in total thromboembolic events at 30 days signaled the increase in appropriate thromboprophylaxis improved outcomes. Major bleeding was rare in both groups.
“This universal tool, which can be adapted into any electronic health record, was able to formalize thrombotic risk in hospitalized medical patients, increase appropriate thromboprophylaxis and decrease major thromboembolic events, and you didn't pay a price for it in terms of increased major bleeding,” said Alex Spyropoulos, MD, the study’s principal investigator and professor of medicine at Northwell Feinstein Institutes for Medical Research in New York City. Dr. Spyropoulos noted the relatively high baseline rate of appropriate in-hospital and at discharge thromboprophylaxis in academic control hospitals suggests potential for greater benefit in non-hospital academic, community and rural hospitals.
Routine prophylaxis doesn’t benefit non-hospitalized patients with COVID-19
Anticoagulation did not prevent hospitalization, death or thrombosis in non-hospitalized patients with COVID-19, according to Rivaroxaban to Reduce the Risk of Major Venous and Arterial Thrombotic Events, Hospitalization and Death in Medically Ill Outpatients with COVID-19 (PREVENT-HD).
The randomized, placebo-controlled, double-blind, event-driven multisite trial enrolled 1,284 patients from August 2020 to April 2022. The primary efficacy outcome, time to first occurrence of a composite endpoint of symptomatic VTE, myocardial infarction, ischemic stroke, acute limb ischemia, non-CNS system embolization, all-cause hospitalization, and all-cause mortality up to day 35, was equivalent in patients receiving the blood thinner, rivaroxaban or placebo.
“Data from this large trial don't support routine antithrombotic prophylaxis for non-hospitalized patients with COVID-19,” said Gregory Piazza, MD, the study’s principal investigator and a cardiologist at Brigham and Women’s Hospital in Boston. “We can put to rest the idea that routine antithrombotic prophylaxis in non-hospitalized patients with symptomatic COVID-19 is necessary.”
Open surgical revascularization compares favorably to endovascular surgery
Bypass with adequate saphenous vein should be considered as a first-line treatment option for suitable patients with chronic limb threatening ischemia (CLTI) as part of fully informed, shared decision-making, according to the Best Endovascular versus Best Surgical Therapy for Patients With Chronic Limb Threatening Ischemia (BEST-CLI) Trial: Clinical Results.
The landmark study randomized 1,830 patients at 150 sites throughout the U.S., Canada, Finland, Italy and New Zealand from August 2014 through October 2019 to open surgical revascularization or endovascular revascularization in two cohorts: patients with available infrainguinal Single Segment Great Saphenous Vein (SSGSV) and those without SSGSV; 1,434 patients with an available SSGSV underwent open surgical revascularization or endovascular revascularization; 396 patients without appropriate SSGSV underwent open surgical revascularization or endovascular revascularization, using an alternative conduit. The trials ran in parallel with credentialed investigators controlling for selection bias.
Patients with adequate saphenous vein who were eligible for either strategy randomized to open surgical revascularization had a 32% reduction in the primary endpoint: major reintervention, or above-ankle amputation (MALE) or all-cause death compared to patients with SSGSV randomized to endovascular revascularization at median 2.7 years follow-up. This cohort also had fewer major amputations or major reinterventions. In patients who did not have adequate saphenous vein, there were no significant differences in the primary efficacy endpoint. Mortality and MACE were similar between treatment strategies over the course of follow-up.
“In CLTI, both surgical and endovascular revascularization are effective and safe, but bypass with adequate saphenous vein is more effective strategy for patients deemed suitable for both open and endovascular approached,” said Alik Farber, MD, the study’s principal investigator and chief of vascular and endovascular surgery at Boston University School of Medicine. “BEST-CLI supports a complementary role for open and endovascular revascularization strategies and highlights the need for expertise in both approaches for optimal care of these patients.”
The study was published in the New England Journal of Medicine following the presentation.
Open and endovascular surgery improved QoL in patients with advanced peripheral artery disease
Open bypass surgery or endovascular treatment equally improved quality of life (QoL) for patients with CLTI, according to Best Endovascular Versus Best Surgical Therapy for Patients With Chronic Limb Threatening Ischemia (BEST-CLI) Trial: Quality of Life Analyses.
QoL, measured using patient-reported data with VascuQoL numerical pain rating scales and other instruments were assessed at trial entry, 30 days, three months, 12 months, 24 months, 36 months and 48 months for the 1,830 patients enrolled in BEST-CLI. Data collection was administered by a surgeon or research coordinator.
There was no significant difference in minimally clinically important difference (MCID), which is correlated with meaningful improvement, between the open surgical or endovascular revascularization cohorts.
“Both treatment strategies resulted in significant and meaningful improvement in health-related quality of life compared to no treatment,” said Matthew Menard, MD, the study’s principal investigator and co-director of endovascular surgery at Brigham and Women’s Hospital in Boston.
In patients without SSGSV, there were no differences between bypass and endovascular treatment on any health-related quality of life measure.