Researchers from the Texas Children’s Hospital reported that their treatment strategy to prevent clot progression in neonates and children with catheter-related arterial thrombosis (CAT) appears to be safe and effective, according to recently released consensus recommendations from the Neonatal Thrombosis and Haemostasis Subcommittee of the Scientific and Standardization Committee (SCC) of the International Society on Thrombosis and Hemostasis (ISTH).
Clay Cohen of Baylor College of Medicine and colleagues at the Texas Children’s Hospital (Hematology and Cancer Centers), both in Houston, Texas, presented the findings at the Thrombosis & Hemostasis Summit of North America (THSNA) 2020 Virtual Conference.
The retrospective study evaluated the treatment outcomes of neonates (younger than 28 days) and children (younger than 1 year) with radiologically proven CAT based on electronic medical records from the Texas Children’s Hospital and aimed to identify prognostic factors of CAT. The primary effectiveness and safety outcomes were contiguous progression of CAT and major bleeding, respectively. Rates of clot resolution and mortality (all-cause and CAT-specific) were also evaluated.
Between 2010 and 2018, patients received either unfractionated heparin (UFH) or low molecular weight heparin (LMWH) as anticoagulation for up to 28 days and were monitored every 7 days by ultrasound.
In total, 99 patients developed CAT secondary to indwelling arterial catheter (IAC; 51 patients) and cardiac catheterization (CC; 48 patients). A total of 68 (52.7%) and 61 (47.3%) diagnoses were due to IAC and CC, respectively.
Contiguous progression occurred in 8 infants (8.1%). Patients received initial anticoagulation with unfractionated heparin (46 patients, 46.5%) and low molecular weight heparin (53 patients, 53.3%). Patients with CAT secondary to CC were more likely to receive LMWH (64.6% vs 43.1% of the IAC group) whereas those with CAT secondary to IAC received UFH more often (56.9% vs 35.4% in the CC group; P =.044).
According to ultrasound data, clot resolution was complete in 60 infants (60.6%), partial in 33 infants (33.3%), and unchanged in 6 infants (6.1%). Variables associated with time to complete resolution were time from arterial manipulation to diagnosis (complete vs noncomplete: median time, 1 day vs 5 days; P =.035) and iliac/femoral involvement (P =.015).
In terms of safety, 1 patient had a major bleeding event, and 3 patients had minor bleeding events. The all-cause mortality was 4% (4 patients); no deaths were related to CAT or CAT treatment.
“Clinical vigilance and early diagnosis of CAT is critical, as shorter time from arterial manipulation to CAT diagnosis was associated with thrombus resolutions,” wrote the authors. “Instituting a doppler ultrasound surveillance program may decrease time to diagnosis and to initiation of anticoagulation.”
The authors noted that extending anticoagulation beyond the 4-week cutoff may provide benefit for patients who had persistent thrombosis at the end of therapy.
Cohen CT, Anderson V, Staggers KA, Diaz R. Short-term outcomes of catheter-related arterial thrombosis in neonates and children. Abstract presented at: THSNA 2020 Thrombosis & Hemostasis Summit of North America; October 27-30, 2020. Abstract 130.