Development of a concept for a personalized approach in the perioperative antiplatelet therapy administration/discontinuation management based on multiple electrode aggregometry in patients undergoing coronary artery surgery

Perioperative Changes in Hemostatic Properties as Assessed by Multiplate, Siemens PFA-200, and ROTEM-A Comparative Study

Objectives: This study sought to determine the platelet function and viscoelastic blood properties in the pre- and postoperative period using three different point-of-care (POC) devices (Multiplate®, Siemens PFA-200® and ROTEM®). We aimed to investigate the association between preoperative POC test results and bleeding outcomes. Postoperative changes in blood hemostatic properties were also evaluated, as well as the agreement between two platelet function analyzers and rotational thromboelastometry parameters. Methods: The study was conducted in a prospective observational fashion. Patients undergoing elective coronary artery bypass graft surgery (CABG) were enrolled. Hemostatic blood properties were assessed using three different POC devices; two platelet function analyzers were used: (1) Impedance aggregometry (Multiplate®) with the arachidonic acid (ASPI) test and adenosine diphosphate (ADP) test. (2) The Siemens INNOVANCE® PFA-200 System with the following assays: the PFA Collagen/EPI test, PFA Collagen/ADP test, and the INNOVANCE® PFA P2Y test. Viscoelastic blood properties were assessed using ROTEM® delta (TEM Innovations GmbH, Munich, Germany). POC tests were performed simultaneously at two different time points: (1) before surgery and (2) on postoperative day 4, respectively. The primary outcome was defined as amounts of perioperative bleeding and transfusion requirements, classified according to the universal definition for perioperative bleeding (UDPB) score. Results: The study recruited a total number of 63 patients undergoing elective isolated coronary artery bypass graft surgery (CABG). Based on the packed red blood cell (PRBC) transfusion requirements, patients with excessive bleeding were not just only frequently transfused (87.5% vs. 48.9%, p = 0.007) but were also transfused with higher amounts of PRBCs (1338.75 mL ± SD 1416.49 vs. 289.36 mL ± 373.07, p < 0.001). The FIBTEM A30 results significantly correlated with excessive bleeding (Correlation Coefficient Rho = -0.280, p = 0.028). Regression analysis revealed FIBTEM A 30 as a strongest predictor of 24 h chest tube output (CTO) (R Square 0.108, p = 0.009). The receiver operating characteristics curve (ROC) analysis showed that a preoperative FIBTEM A30 < 10.86 mm predicted excessive bleeding with 94% sensitivity and 50% specificity (ROC AUC 68.4%). The multiplate ASPI test results were significantly higher (35.24 AUC ± SD 22.24 vs. 19.43 AUC ± SD 10.74) and the proportion of Aspirin responders was significantly lower (42.4% vs. 76.7%, p = 0.006) in patients considered to have insignificant bleeding. On postoperative day 4, we found platelet hyperreactivity in the ASPItest coupled with a ROTEM-documented shift towards hypercoagulability. Conclusions: Modern hemostatic management and perioperative antiplatelet therapy (APT) administration/discontinuation management should be guided by thromboelastometry and platelet function testing. Prospective interventional trials are necessary to validate such an approach in multicentric studies.

The role of evidence-based algorithms for rotational thromboelastometry-guided bleeding management

Rotational thromboelastometry (ROTEM) is a point-of-care viscoelastic method and enables to assess viscoelastic profiles of whole blood in various clinical settings. ROTEM-guided bleeding management has become an essential part of patient blood management (PBM) which is an important concept in improving patient safety. Here, ROTEM testing and hemostatic interventions should be linked by evidence-based, setting-specific algorithms adapted to the specific patient population of the hospitals and the local availability of hemostatic interventions. Accordingly, ROTEM-guided algorithms implement the concept of personalized or precision medicine in perioperative bleeding management (‘theranostic’ approach). ROTEM-guided PBM has been shown to be effective in reducing bleeding, transfusion requirements, complication rates, and health care costs. Accordingly, several randomized-controlled trials, meta-analyses, and health technology assessments provided evidence that using ROTEM-guided algorithms in bleeding patients resulted in improved patient’s safety and outcomes including perioperative morbidity and mortality. However, the implementation of ROTEM in the PBM concept requires adequate technical and interpretation training, education and logistics, as well as interdisciplinary communication and collaboration.

Whole Blood Platelet Aggregation Test and Prediction of Hemostatic Difficulty After Tooth Extraction in Patients Receiving Antiplatelet Therapy

When patients on antiplatelet therapy (APT) require minor invasive surgery, APT is usually continued to limit the risk of thrombosis. However, the possibility of hemostatic difficulties necessitates the monitoring of platelet aggregation to prevent unexpected bleeding. We examined whether whole blood aggregometry as a point-of-care testing (POCT) could be useful as a tool for predicting hemostatic difficulties. Sixty-five patients receiving APT and 15 patients who were not receiving APT were enrolled in the present study; all patients were scheduled to undergo a tooth extraction. Whole blood samples were obtained and were examined using multiple electrode aggregometry. The aggregometry was performed using arachidonic acid (AA), adenosine diphosphate (ADP), and thrombin receptor activating peptide. Hemostatic difficulty was defined as a need for more than 10 minutes of compression to achieve hemostasis. The AA test results were significantly lower in patients treated with aspirin (control: 97.7 [29.0] U, aspirin: 14.5 [7.2] U, P < .001). The ADP test results were also significantly lower in patients treated with a P2Y₁₂ inhibitor (control: 77.7 [21.7] U, P2Y₁₂ inhibitor: 37.3 [20.4] U, P < .01). Six of the examined cases exhibited hemostatic difficulties. The cutoff values for the prediction of hemostatic difficulty were 16.5 U for the AA test (sensitivity, 0.833; specificity, 0.508) and 21 U for the ADP test (sensitivity, 0.847; specificity, 0.500). Our study showed that whole blood aggregometry was useful as a POCT for the prediction of hemostatic difficulties after tooth extraction in patients receiving APT.

Treatment of Intra- and Extracranial Aneurysms Using the Flow-Redirection Endoluminal Device: Multicenter Experience and Follow-Up Results

BACKGROUND AND PURPOSE

Flow diversion emerged as a crucial treatment option for intracranial aneurysms. We report a multicenter retrospective analysis of the safety and efficacy in the treatment of intracranial aneurysms with the Flow-Redirection Endoluminal Device (FRED) flow diverter, a dual-layer flow-modulation device.

MATERIALS AND METHODS

All intracranial aneurysms treated with the FRED between March 2013 and February 2016 at 4 neurovascular centers were included. Angiographic and clinical results were retrospectively analyzed, including all follow-up examinations. Aneurysms were unruptured in 44 cases, whereas 8 treatments were due to an acute SAH from the target aneurysm.

RESULTS

Successful implantation of the FRED was possible in 96.2% (50/52) of cases. At 3-month follow-up, complete occlusion was determined in 58.1% (25/43) and near-complete in 25.6% (11/43). At 12-month follow-up, aneurysm occlusion was complete in 75.0% (27/36) and near-complete in 22.2% (8/36). The overall acute and late thromboembolic and hemorrhagic complication rate was 17.3% (9/52), with a permanent treatment-related morbidity and mortality of 4.0% (2/50) and 2.0% (1/50), respectively, to date.

CONCLUSIONS

The FRED device offers an effective tool in the treatment of intracranial aneurysms. The dual-layer design promotes contemporary and stable long-term occlusion rates. Sufficient device expansion should be documented by angiographic CT. Further studies might help to identify a more optimal antiplatelet regimen to avoid thromboembolic complications during the follow-up period.

Developments in surgical revascularization to achieve improved morbidity and mortality

Coronary artery bypass graft surgery remains the main treatment modality for multivessel coronary artery disease and has consistently been demonstrated to have significantly lower rates of major adverse cardiac and cerebrovascular events in comparison to percutaneous coronary intervention. In this article we will explore the advances over time and the recent refinements in the techniques of surgical revascularization and how these contribute to the superior outcome profile associated with coronary artery bypass graft surgery. These include the current outcome status of coronary artery bypass grafting; the major landmark trials, registries and meta-analyses comparing coronary artery bypass grafting and percutaneous coronary intervention; the developments in coronary artery disease lesion classification; the techniques for the physiological assessment of coronary artery lesions; bypass grafting using arterial conduits; the role of off-pump coronary artery surgery; the outcomes of reoperative surgery; hybrid techniques for coronary revascularization; minimally invasive coronary artery surgery and finally robotic surgery.