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)
Reoperation for bleeding after CABG
30
8,75%
24
7,00%
5,25%
CABG-related TIMI major bleeding
18
10 x
3,50%
12
1,75%
6
0,00%
no cplopidogrel n=165
clopidogrel n=59
Hongo et al. JACC 2002; 40(2): 231-7.
0
4x
clopidogrel n=189
prasugrel n=179
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.
2h
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
• Requires pipetting
• Whole blood, no requirements for
(consider Verify Now®)
sample preparation
• Dependent to levels of
• Low sample volume (0.3ml/test)
calcium (Hirudin is
• Multiple agonists available allowing
preferred to citrate)
a wide range of different acquired • Sensitive to
and inherited platelet dysfunction
thrombocytopenia
detection
(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.