Antithrombotic drug removal from whole blood using Haemoadsorption with a porous polymer bead sorbent.

AIM: To evaluate the ability of the DrugSorb™-AntiThrombotic Removal (ATR) haemoadsorption device utilizing porous polymer bead sorbent technology to remove three commonly used antithrombotic drugs from whole blood. METHODS AND RESULTS: We evaluated the removal of apixaban, rivaroxaban, and ticagrelor by the DrugSorb-ATR haemoadsorption device in a benchtop clinical scale model using bovine whole blood. Blood spiked at clinically relevant concentrations of an antithrombotic agent was continuously circulated through a 300-mL DrugSorb-ATR haemoadsorption device at a flow rate of 300 mL/min. Drug concentration was monitored over 6 h to evaluate drug removal. Results were compared with a control circuit without the haemoadsorption device. Removal rates at 30, 60, 120, and 360 minutes were: apixaban: 81.5%, 96.3%, 99.3% >99.8%; rivaroxaban: 80.7%, 95.1%, 98.9%, >99.5%; ticagrelor: 62.5%; 75%, 86.6%, >95% (all P <0.0001 vs. control). Blood pH and haematological parameters were not significantly affected by the DrugSorb-ATR haemoadsorption device when compared with the control circuit. CONCLUSION: DrugSorb-ATR efficiently removes apixaban, rivaroxaban, and ticagrelor in a clinical-scale benchtop recirculation circuit with the bulk of removal occurring in the first 60 minutes. The clinical implications of these findings are currently investigated in patients undergoing on-pump cardiothoracic surgery in two US pivotal trials (ClinicalTrials.gov Identifiers: NCT04976530 and NCT05093504).

Biphasic effects of hemodialysis on platelet reactivity in patients with end-stage renal disease: a potential contributor to cardiovascular risk.

BACKGROUND: Cardiovascular disease is rampant in patients with end-stage renal disease (ESRD), and increased platelet reactivity may contribute. This study is designed to determine effects of hemodialysis in patients with ESRD on platelet reactivity per se. METHODS: Platelet reactivity was determined by flow cytometry in 36 patients with ESRD undergoing hemodialysis. Blood was obtained from arterial and venous ends of the hemodialysis circuit at the beginning and end of the dialysis session. Platelet reactivity was defined with respect to capacity to bind fibrinogen (activation of glycoprotein IIb-IIIa) and expression of P-selectin in response to adenosine diphosphate (ADP; 0, 0.2, and 1.0 micromol/L). Comparison studies were performed with 55 patients with coronary artery disease (CAD) and 38 healthy subjects. RESULTS: Platelet reactivity was increased by exposure to the dialysis circuit (capacity to bind fibrinogen: arterial, 28% +/- 13%; venous, 47% +/- 20%; P < 0.001). Despite this effect, surface expression of P-selectin in response to 1 micromol/L of ADP was lower at the end of the dialysis session (arterial blood at its onset, 40% +/- 16%; arterial blood at its conclusion, 24% +/- 15%; P < 0.05). Confocal microscopy showed increased nonspecific association of fibrinogen with platelets after dialysis, suggesting that increased aggregation after dialysis may be secondary to effects of dialysis on fibrinogen binding, rather than on platelet reactivity. Platelet reactivity was increased similarly in patients with ESRD and those with CAD compared with healthy subjects. CONCLUSION: Although interaction between platelets and the dialysis circuit increases platelet reactivity, continued dialysis decreases platelet reactivity.

Systemic inflammation after drug-eluting stent placement.

BACKGROUND: Systemic inflammation after coronary intervention identifies patients at increased risk of subsequent cardiac events. Cardiac events are less frequent after use of drug eluting stents (DES) compared with bare metal stents (BMS). Thus, we sought to determine whether attenuation of the systemic inflammatory response was contributing to the improved outcomes. METHODS: A prospective registry was initiated in late 2003. Peripheral venous blood samples from 75 patients undergoing percutaneous coronary intervention (PCI) were obtained before PCI, and both 1 hour and 24 hours after stenting. The concentrations of C-reactive protein (CRP), interleukin-6 (IL-6) and interleukin-1 receptor antagonist (IL1-Ra) were determined by ELISA. Eleven patients were excluded from the analysis because they had both DES and BMS. RESULTS: Patients treated with BMS (n=29) compared with DES (n=34) had a higher incidence of marker-positive acute coronary syndromes (40% vs. 17%, p=0.06), vein graft PCI (p=0.02) and a larger final balloon diameter (p=0.04). Consistent with the lower baseline clinical risk, pre-PCI concentrations of cytokines were lower in the DES group (p=0.04 for IL-6 and p=0.08 for CRP). Comparable and significant increases in CRP, IL-6 and IL1-Ra were evident 24 hours after PCI in patients treated with either DES or BMS. After controlling for baseline levels of CRP, there remained a similar and robust (300%) relative increase in CRP for both DES and BMS patients. CONCLUSIONS: The inflammatory response to PCI appears similar in those treated with DES and BMS. Accordingly, the reduction in restenosis after DES is likely not mediated by attenuation of the systemic markers CRP, IL-1Ra, or IL-6.