Preoperative antithrombotic management: before cardiac surgery S. Demertzis
Facts > CABG-related bleeding complications & perioperative acute coronary events are strongly influenced by the management of pre- & postop antithrombotic therapy > Significant postop bleeding with transfusions of blood & blood products increase the risk of death & compromise the long-term benefit of CABG > Lack of randomized trials on different strategies
It s all a matter of perspective Activated platelets Stent thrombosis - acute MI (the bad) Hemostasis in surgery (the good) Suture in arterial lumen (x1000 magnification - REM)
and mastery of navigation and troubleshooting! The Odyssey Odysseus is hindered by the efforts of Poseidon and the sea monsters throughout the ocean. Odysseus faced both Charybdis and Scylla while rowing through a narrow channel. He ordered his men to avoid Charybdis thus forcing them to pass near Scylla, which resulted in the death of six of his men. Later, stranded on a raft, Odysseus was swept back through the strait to face Scylla and Charybdis once more. This time, Odysseus passed near Charybdis. His raft was sucked into Charybdis' maw, but he survived by clinging to a fig tree growing on a rock over her lair. On the next outflow of water, his raft was expelled. Odysseus recovered it and paddled away safely.
Cardiac Surgery under Double Antiplatelet Therapy (DAPT) 8,75% Reoperation for bleeding after CABG 30 CABG-related TIMI major bleeding 7,00% 24 5,25% 10 x 18 4 x 3,50% 12 1,75% 6 0,00% no cplopidogrel n=165 clopidogrel n=59 0 clopidogrel n=189 prasugrel n=179 Hongo et al. JACC 2002; 40(2): 231-7. TRITON TIMI 38 study, N Engl J Med 2007;357:2001-15.
An important issue
Current recommendations
Coronary artery bypass grafting-related bleeding complications in real-life acute coronary syndrome patients treated with clopidogrel or ticagrelor EJCTS 46 (2014) 699-705 Prospective observational study n= 405 consecutive CABG patients with ACS aspirin and ticagrelor (n = 173) or aspirin and clopidogrel (n = 232).
Know your enemy and know yourself and you can fight a hundred battles without disaster. (Sun Tzu - The Art of War (chinese: trad. 孫子兵法, simp. 孙子兵法, lit. "Master Sun's Rules for Army")
Primary hemostasis - Platelet physiology Casso G. et al.(2015). Point-of-care platelet function tests. In C. E. Marcucci & P Schoettker (Ed.), Perioperative Hemostasis (pp. 45-63). Berlin Heidelberg, Springer.
Antiplatelet agents Substance Commercial product Route Half-life Clopidogrel Plavix p.o. 7.5 h Prasugrel Effient, Iscover p.o. 3.7 h Ticagrelor Brilique, Brilinta, Possia p.o. 7-10 h Cangrelor Kengrexal i.v. 3 min Abciximab ReoPro i.v. 23 h Eptifibatid Integrillin i.v. 2.5 h Tirofiban Aggrastat i.v. 2 h mod. from Chassot et al. in Marcucci, Schoettker (eds.) Perioperative Hemostasis, Springer 2015
A game changer: Point-of-Care platelet & coagulation testing ROTEM Multiplate
Multiplate - concept Casso G. et al.(2015). Point-of-care platelet function tests. In C. E. Marcucci & P Schoettker (Ed.), Perioperative Hemostasis (pp. 45-63). Berlin Heidelberg, Springer.
Multiplate - concept II
Multiplate - working mechanism
Multiplate - working mechanism
Multiplate - Summary Assessment of drug effect + Aspirin P2Y12 inhibitors GP IIb/IIIa inhibitors Rapid (<10 min) and easy test Whole blood, no requirements for sample preparation Low sample volume (0.3ml/test) Multiple agonists available allowing a wide range of different acquired and inherited platelet dysfunction detection Requires pipetting (consider Verify Now ) Dependent to levels of calcium (Hirudin is preferred to citrate) Sensitive to thrombocytopenia (PC > 150 G/l ASPI test, >100 G/l ADP and COL test, > 50 G/l TRAP test) Casso G. et al.(2015). Point-of-care platelet function tests. In C. E. Marcucci & P Schoettker (Ed.), Perioperative Hemostasis (pp. 45-63). Berlin Heidelberg, Springer.
Ann Thorac Surg 2011;91:123 30 ADP Test AUC < 31 U Retrospective study n=87 Preoperative evaluation of M-ADP
ROTEM - the new thrombelastogram EXTEM Tissue thromboplastin -tissue factor INTEM Contact phase - intrinsic system FIBTEM As in EXTEM but with blocked platelets - fibrin formation & polymersation APTEM Aprotinin inhibits fibrinolysis in vitro HEPTEM As in INTEM but with blocked heparin
Clinical scenarios Acute STEMI - PCI not successful / too risky: emergent surgery > high probability of active DAPT (prehospital protocols) and periprocedural GP IIb/IIa antagonists > platelet function test + alert the blood bank! > hemorrhagic complications highly probable Acute NSTEMI - instable patient: urgent / emergent surgery > pre-hospital protocols should be conservative regarding DAPT > bridge-to-surgery with i.v. heparine, GP IIb/IIa antagonists (soon with cangrelor) possible Acute / subacute NSTEMI - subacute STEMI: stable hospitalized patient for urgent surgery > withdrawal of DAPT > bridge-to-surgery with i.v. heparine, GP IIb/IIa antagonists (soon with cangrelor) > timing of surgery according to platelet- and coagulation testing (POC)
Conclusions > Major diffuse bleeding after CABG is a serious complication with a significant impact on the final outcome - it has to be considered seriously > DAPT introduction in the pre-hospital setting has to be conscious and wise! > Discontinuation of DAPT ± possible bridging (heparine, GP IIb/IIa antagonists, cangrelor) is advised - clinical judgement! > Platelet function monitoring (POC) can guide the Extended Heart Team in the timing / scheduling of surgery
Thanks to the Extended Heart Team! Non invasive Cardiology Invasive Cardiology Cardio-anaesthesiology & Intensive Care Unit Cardiac Surgery Special thanks to Dr. Casso and Dr. Cassina (Cardio-anaesthesiology & ICU) for the precious help in this difficult navigation (POC) and for their support for this presentation.