Acute Arterial Thromboembolism in Patients with COVID-19 in the New York City Area.

BACKGROUND: Coronavirus disease 2019 (COVID-19) predisposes to arterial and venous thromboembolic complications. We describe the clinical presentation, management, and outcomes of acute arterial ischemia and concomitant infection at the epicenter of cases in the United States. METHODS: Patients with confirmed COVID-19 infection between March 1, 2020 and May 15, 2020 with an acute arterial thromboembolic event were reviewed. Data collected included demographics, anatomical location of the thromboembolism, treatments, and outcomes. RESULTS: Over the 11-week period, the Northwell Health System cared for 12,630 hospitalized patients with COVID-19. A total of 49 patients with arterial thromboembolism and confirmed COVID-19 were identified. The median age was 67 years (58-75) and 37 (76%) were men. The most common preexisting conditions were hypertension (53%) and diabetes (35%). The median D-dimer level was 2,673 ng/mL (723-7,139). The distribution of thromboembolic events included upper 7 (14%) and lower 35 (71%) extremity ischemia, bowel ischemia 2 (4%), and cerebral ischemia 5 (10%). Six patients (12%) had thrombus in multiple locations. Concomitant deep vein thrombosis was found in 8 patients (16%). Twenty-two (45%) patients presented with signs of acute arterial ischemia and were subsequently diagnosed with COVID-19. The remaining 27 (55%) developed ischemia during hospitalization. Revascularization was performed in 13 (27%) patients, primary amputation in 5 (10%), administration of systemic tissue- plasminogen activator in 3 (6%), and 28 (57%) were treated with systemic anticoagulation only. The rate of limb loss was 18%. Twenty-one patients (46%) died in the hospital. Twenty-five (51%) were successfully discharged, and 3 patients are still in the hospital. CONCLUSIONS: While the mechanism of thromboembolic events in patients with COVID-19 remains unclear, the occurrence of such complication is associated with acute arterial ischemia which results in a high limb loss and mortality.

Stent-grafts improve secondary patency of failing hemodialysis grafts.

PURPOSE: Failing hemodialysis grafts continue to pose a challenge in the care of patients with end-stage renal disease (ESRD). We review our experience using percutaneous stent-grafts for the treatment of venous outflow stenosis and occlusion in order to assess their efficacy in nonautologous graft salvage. METHODS: This is a retrospective review of patients treated with percutaneous Viabahn® stent-grafts for failing hemodialysis arteriovenous grafts (AVGs), between 6/2006 and 12/2009. All stent-grafts were deployed across the venous anastomosis to address the outflow obstruction. Patency and re-intervention rates were estimated using Kaplan-Meier analysis. RESULTS: Twenty patients had stent-grafts placed. Successful stent-grafting was defined as <30% residual stenosis and the ability to dialyze through the graft post-treatment. Technical success for stent-grafting was 100%. Median follow-up was 23 months (range 3 to 37 months). Stent-graft patency at 6 months: 94.7%, 12 months: 94.7%, 18 months: 82.1%, 24 months: 82.1%, 36 months: 82.1%. Freedom from re-intervention was 69% at 24 months and 50% at 36 months. Two AVGs failed and had to be removed without further interventions, because of complete occlusion and infection. Two patients (10%) required re-intervention for arterial inflow stenosis. One patient (5%) required balloon angioplasty and stenting of stenosis distal to the stent-graft. One patient (5%) developed in-stent stenosis and was treated with placement of a new stent. Graft salvage rate was 80% at 36 months. CONCLUSIONS: Stent-grafts can be successfully used to improve freedom from re-intervention rates and overall patency rates of failing AVGs.

Primary balloon angioplasty plus balloon angioplasty maturation to upgrade small-caliber veins (<3 mm) for arteriovenous fistulas.

OBJECTIVE: Small-diameter veins are often a limiting factor for the successful creation of arteriovenous fistulas (AVFs). This study evaluated the use of intraoperative primary balloon angioplasty (PBA) as a technique to upgrade small-diameter veins during AVF creation. Sequential balloon angioplasty maturation (BAM) was evaluated as a technique to salvage failed fistulas, expedite maturation, and improve the patency of AVFs after PBA. METHODS: Sixty-two PBAs were performed in 55 patients with an intent-to-treat using an all-autologous policy. PBAs of veins were performed just before AVF creation using 2.5- to 4-mm angioplasty balloons (1- to 1.5-mm larger than the nominal vein diameter). PBAs were performed through the spatulated end of the vein for a length of up to 8 cm using hydrophilic guidewires and hand inflations without fluoroscopy. BAM was performed in 53 of the 62 PBAs at 2, 4, and 6 weeks after the PBA. Successful outcome was determined as the functional ability to use the fistula for hemodialysis without surgical revision. RESULTS: Of the 62 PBAs, 53 (85.4%), comprising 47 of the original AVFs and 6 new site AVFs created at other sites, remained patent and subsequently underwent BAM with a resulting functional AVF. Fifteen of the 47 original AVFs: 14 due to occlusion; one AVF with a steal was ligated. Seven of the 14 fistulas that occluded were salvaged using recanalization techniques during sequential BAMs. Two of the seven fistulas that were not salvaged required AVGs (3%), and five patients underwent redo AVFs using alternative veins. These five cases were also performed using PBAs and BAMs technique. One patient with a functioning fistula underwent intentional ligation for steal syndrome and also underwent an alternative site AVF, PBA, and BAM. At 3 months, 53 AVFs were functional and successfully used for dialysis. Overall, a working AVF was obtained at the initial site in 47 of 55 patients (85.4%), and 53 (96.3%) received working AVFs that were functioning for dialysis access. CONCLUSIONS: Small or suboptimal veins can undergo PBA and then be matured to create functioning AVFs 90% autogenous AVF rates can be achieved using PBA and BAM. BAM can be successfully used to mature AVFs created from small veins and salvage thrombosed AVFs in many cases. The use of these techniques may decrease the number of patients requiring AVGs and indwelling catheters.