Modelling the impact of changes to abdominal aortic aneurysm screening and treatment services in England during the COVID-19 pandemic.

BACKGROUND: The National Health Service (NHS) abdominal aortic aneurysm (AAA) screening programme (NAAASP) in England screens 65-year-old men. The programme monitors those with an aneurysm, and early intervention for large aneurysms reduces ruptures and AAA-related mortality. AAA screening services have been disrupted following COVID-19 but it is not known how this may impact AAA-related mortality, or where efforts should be focussed as services resume. METHODS: We repurposed a previously validated discrete event simulation model to investigate the impact of COVID-19-related service disruption on key outcomes. This model was used to explore the impact of delayed invitation and reduced attendance in men invited to screening. Additionally, we investigated the impact of temporarily suspending scans, increasing the threshold for elective surgery to 7cm and increasing drop-out in the AAA cohort under surveillance, using data from NAAASP to inform the population. FINDINGS: Delaying invitation to primary screening up to two years had little impact on key outcomes whereas a 10% reduction in attendance could lead to a 2% lifetime increase in AAA-related deaths. In surveillance patients, a 1-year suspension of surveillance or increase in the elective threshold resulted in a 0.4% increase in excess AAA-related deaths (8% in those 5-5.4cm at the start). Longer suspensions or a doubling of drop-out from surveillance would have a pronounced impact on outcomes. INTERPRETATION: Efforts should be directed towards encouraging men to attend AAA screening service appointments post-COVID-19. Those with AAAs on surveillance should be prioritised as the screening programme resumes, as changes to these services beyond one year are likely to have a larger impact on surgical burden and AAA-related mortality.

Systemic Thrombolysis as Initial Treatment of COVID-19 Associated Acute Aortoiliac and Lower Extremity Arterial Thrombosis.

SARS-CoV-2 (COVID-19) patients with associated thromboembolic events have demonstrated poor outcomes despite the use of anticoagulation therapy and surgical intervention. We present a COVID-19 patient with acute limb ischemia, secondary to extensive thrombosis of an aortic aneurysm, iliac arteries, and infrainguinal arteries. Initial treatment with systemic thrombolysis, which restored patency of the aortoiliac occlusion, was followed by open thrombectomies of the infrainguinal occlusions.

Acute Thrombosis of an Aortic Prosthetic Graft in a Patient with Severe COVID-19-Related Pneumonia.

BACKGROUND: COVID-19 infection has been reported to be related with an increased risk of thrombotic complications because of the hypercoagulability state and inflammation. At the moment, no reports are available regarding thrombosis of prosthetic vascular grafts. We present the case of a patient with COVID-19-related pneumonia, who suffered from the acute thrombosis of a previously implanted aortic graft. METHODS AND RESULTS: A 67-year-old male patient, who had undergone open repair of an abdominal aortic aneurysm with a bifurcated graft 6 years before, was admitted to the emergency department with high fever for a week without cough or dyspnea. Thoracic ultrasound showed signs of bilateral interstitial pneumonia, and the Sars-Cov-2 swab was positive. Antiretroviral therapy and prophylactic low molecular weight heparin treatment were initiated. Owing to the progressive impairment of the respiratory function, the patient was intubated after eight days from the admission, the day after he showed signs of bilateral acute limb ischemia. A duplex ultrasound demonstrated the complete thrombosis of the aortic graft without flow at the femoral level. An urgent angio-computed tomography scan for revascularization purpose was requested, but the patient died on the arrival in the radiological suite. CONCLUSIONS: Acute thrombosis of vascular prosthetic grafts is a possible, catastrophic complication of COVID-19 infection. In COVID-19 patients with prosthetic graft, an aggressive antithrombotic treatment could be considered to prevent such an event.