Fixed‐dose aspirin monotherapy compared with thromboelastography directed antiplatelet therapy in long‐term management of left ventricular assist devices

Abstract

Background and Aim The role of thromboelastography (TEG) in managing antiplatelet therapy (APT) in left ventricular assist devices (LVADs) is controversial. Our aim was to determine whether removal of TEG from an LVAD‐specific APT protocol reduced late‐onset bleeding without increasing thromboembolic complications. Methods We performed a single‐center, retrospective cohort study including all recipients of a continuous‐flow LVAD between April 2005 and November 2019 (n = 293). LVAD recipients before June 1, 2017 (n = 221) whose APT was monitored and adjusted using TEG were compared with LVAD recipients after June 1, 2017 (n = 72) where TEG was not utilized. Occurrence of late‐onset bleeding events after postoperative Day 7 and thromboembolic events were collected. APT doses, warfarin use and International normalized ratio (INR) values were collected at discharge and at 1, 3, 6, and 12‐months postimplantation. Results Over a median 12‐month follow‐up, INTERMACS major bleeding events occurred in 35% of patients where TEG was utilized compared with 29% where TEG was not utilized (p = 0.375), and procedural intervention was required in 29% compared with 18%, respectively (p = 0.058). Use of TEG was associated with higher doses of aspirin (>325 mg) (41% compared with none) and use of a second antiplatelet (dipyridamole) (43% compared to 1%). Despite this, there was no significant difference in thromboembolic events (15% in each). Conclusions Our study suggests the use of TEG led to increased doses of aspirin as well as adding a second antiplatelet agent, without improving outcomes in LVAD recipients. Furthermore, the removal of TEG from an LVAD‐specific APT protocol did not worsen thromboembolic outcomes.

Thromboelastography and multiplate tests for current rotational left ventricular assist device management

“…[1][2][3]6,7 Initially described in 1948 by Hertert, thromboelastography (TEG) allows real-time assessment of the whole-blood viscoelastic clot strength. 4,8 ROTEM evolved from TEG; both devices generate outputs by transducing changes in the viscoelastic strength of small samples (300 µl) of clotting blood, to which a constant rotational force is applied. Such point-of-care devices allow visual assessment of blood coagulation (clot formation, propagation and stabilization, and dissolution).…”

“…Increasingly, ROTEM and TEG data are being incorporated into vertical algorithms used to diagnose and treat bleeding in high-risk populations, such as patients undergoing cardiac surgery and those with blunt trauma. 4,8 There is evidence to suggest that such algorithms may reduce the need for transfusion, although further study is needed. 4,8 The primary clinical indication for the use of ROTEM or TEG devices is an urgent need for data on the likelihood of hemostatic defects in bleeding patients.…”

“…4,8 There is evidence to suggest that such algorithms may reduce the need for transfusion, although further study is needed. 4,8 The primary clinical indication for the use of ROTEM or TEG devices is an urgent need for data on the likelihood of hemostatic defects in bleeding patients. The use of ROTEM and TEG data in transfusion algorithms, either alone or in combination with other rapid platelet function tests such as whole-blood platelet multiple electrode aggregometry (MEA), facilitates goal-directed hemostatic therapy; nonerythrocyte blood products are administered to address specific deficiencies.…”

“…The use of ROTEM and TEG data in transfusion algorithms, either alone or in combination with other rapid platelet function tests such as whole-blood platelet multiple electrode aggregometry (MEA), facilitates goal-directed hemostatic therapy; nonerythrocyte blood products are administered to address specific deficiencies. 4,8 Ideally, this should reduce the need for total allogeneic blood product administration compared to an empirical transfusion strategy, or a strategy based on laboratory tests with long turnaround times. The turnaround times of standard laboratory tests (PT, aPTT, fibrinogen concentration, and platelet count) are generally considered too long (45-60 min in some cases) to guide hemostatic therapy in severely bleeding patients, whereas meaningful ROTEM and MEA measurements are available within 15-20 min.…”

“…Early ROTEM-and TEG-guided transfusion algorithms are horizontally organized; the order in which abnormalities are identified and treated is not defined and the interdependence of coagulation is not addressed. 4,8 However, the current algorithms are vertically organized and define a sequence of interventions based on ROTEM and TEG analyses, as well as clinical observations that address the multifactorial nature of the perioperative coagulopathies.…”