Rhett StentsPlatelets
Transcript of Rhett StentsPlatelets
-
7/27/2019 Rhett StentsPlatelets
1/31
Perioperative management of
antiplatelet therapy in patientswith coronary artery stents
Esi Rhett, MD
Davide Cattano, MD PhD
The Department of Anesthesiology Grand Round Series
March 19, 2009
http://www.uthouston.edu/index/index.htm -
7/27/2019 Rhett StentsPlatelets
2/31
Disclaimer
No financial interest
Patient verbal consent has been obtained
All patients information has been de-identified
and the use of it is restricted to quality
improvement of medical practice
-
7/27/2019 Rhett StentsPlatelets
3/31
Learning Objectives
Understand the value of preoperative cardiac evaluation and risk
stratification and the clinical indication for antiplatelet therapy.
Basic knowledge of platelet function and coagulation.
How aspirin and clopidogrel work
Understand the current ACC/AHA and ASA guidelines on the use of
thromboprophylaxis and coronary stents and the limitations.
How to (ideally) approach the patient on antiplatelet therapy
Introduction to the concept of resistance to antiplatelet medications
Future projects
-
7/27/2019 Rhett StentsPlatelets
4/31
Introduction
Heart disease continues to be the #1 cause ofmorbidity and mortality in the United States andwestern nations.
Acute coronary syndrome- conditions related tomyocardial ischemia ranging from stable angina toQ-wave myocardial infarction. (1.6 million Americans: 700,000unstable angina and 900,000 divided btwn STEMI and NSTEMI)
Percutaneous coronary intervention (balloonangioplasty and stent placement) offers patientsimproved quality of life by decreasing angina andrisk for myocardial infarction and death.
-
7/27/2019 Rhett StentsPlatelets
5/31
Introduction
A major concern after successful coronary artery
stent placement is the potential for acute stent
thrombosis, with subsequent myocardial infarctionand death.
American Society of Anesthesiologists. Practice Alert for the Perioperative Management ofPatients with Coronary Stents. Anesthesiology 2009; 110(1): 22-23.
-
7/27/2019 Rhett StentsPlatelets
6/31
Introduction
To prevent stent thrombosis,cardiologists recommenddual antiplatelet medications
consisting of a combinationof aspirin and athienopyridine usuallyclopidogrel.
However, when these patients
present for surgery, there is afear that platelet dysfunctioncan cause surgical site
bleeding.
-
7/27/2019 Rhett StentsPlatelets
7/31
Why are these patients on
antiplatelet therapy anyway? Percutaneous Coronary Intervention is inherently
thrombogenic because it disturbs the artery walls.
Drug eluting stents slowly release medications toprevent reendotheliaztion of the artery wall, this
leaves tissue factor exposed where the coagulation
cascade and platelet aggregation can occur.
Surgery is thrombogenic because it causes tissue
damage and inflammation.
-
7/27/2019 Rhett StentsPlatelets
8/31
The patient:
Mr. Smyth, 36 year old Caucasian man
Presented to the Anesthesia Clinic December 2008, repeat
anterior cervical 6 and 7 decompression with fusion
MedHx: HTN, dyslipidemia, DM II for 3 years, cervical
herniated disc, ACS in 2003, 2008
In March 2003, when he was only 31 years old, he had an
episode of unstable angina, angiogram revealed a >95%
occlusion in the LAD and received a sirolimus drug eluting
stent.
-
7/27/2019 Rhett StentsPlatelets
9/31
The patient cont:
PSx: March 2008, first anterior cervical 6-7 discdecompression with fusion, uneventful hospitalcourse.
He reported had another MI 3/25/08 in Dallas.
Meds: clopidogrel, aspirin (last dose one weekbefore clinic visit), ramipril, metoprolol,
glucophage, atorvostatin, and hydrocodone-acetaminophen
Social: non smoker, occ ETOH
-
7/27/2019 Rhett StentsPlatelets
10/31
What other information do you need to
determine the patients risk for surgery? He is unable to give any family history of cardiac disease
or premature cardiac death because he is adopted.
He tolerates some physical activity; he is able to do work
around the house and climb stairs without any chest pain or
shortness of breath.
Cath(5/08) LAD stent patent with multiple other vessel
with disease but recommend medical management for now
ECHO: EF 60-65%
EKG: normal sinus rhythm, no evidence of ST changes or
Q waves
-
7/27/2019 Rhett StentsPlatelets
11/31
What other information do you need to
determine the patients risk for surgery?
Vital signs: T96.5, B/P 123/79, P78, 97% on RA
Laboratory data significant for elevated glucose of
196mg/dL, Hb 13.7, all other labs wnl.
-
7/27/2019 Rhett StentsPlatelets
12/31
Would you want to stop his
clopidogrel and aspirin for this
procedure again? Plan A: stop both clopidogrel and ASA
Plan B: continue both clopidogrel and ASA
Plan C: Admit the patient for short term
antiplatelet therapy
Plan D: cancel the surgery
-
7/27/2019 Rhett StentsPlatelets
13/31
American Society of Anesthesiologists. Practice Alert for the
Perioperative Management of Patients with Coronary
Stents. Anesthesiology 2009; 110(1): 22-23.2007 Science Advisory
Drug Eluting stents (DES)- delay non cardiacsurgery with high risk bleeding for 12
months, thienopyridine and ASA for 12months
Bare Metal Stents (BMS)- delay electivenon-cardiac surgery a minimum of 1 month(4-6 weeks depending on type of BMS), ASA4-6 weeks
(Angioplasty alone delay for 3 weeks)
-
7/27/2019 Rhett StentsPlatelets
14/31
Fleisher LA, et al. ACC/AHA 2007 Guidelines on
Perioperative Cardiovascular Evaluation and Care for
Noncardiac Surgery: Executive Summary. J Am Coll Cardiol2007; 50(17): 1707-1732.
In patients who have received drug-eluting
coronary stents and who must undergo
urgent surgical procedures that mandate thediscontinuation of the thienopyridine
therapy, it is reasonable to continue aspirin
if at all possible and restart thethienopyridine as soon as possible.
-
7/27/2019 Rhett StentsPlatelets
15/31
-
7/27/2019 Rhett StentsPlatelets
16/31
-
7/27/2019 Rhett StentsPlatelets
17/31
Coagulation/Platelet
-
7/27/2019 Rhett StentsPlatelets
18/31
Hemostasis
Vascular spasm
Platelet plug (primary
hemostasis) Blood coagulation
(secondary
hemostasis)
Platelet Plug
3 Stages
1.Adhesion2. Release of platelet
granules
3.Aggregation
Morgan and Mihkail, Hepatic Physiology and Anesthesia p783-785
-
7/27/2019 Rhett StentsPlatelets
19/31
Clopidogrel: mechanism of action
-
7/27/2019 Rhett StentsPlatelets
20/31
Aspirin: mechanism of action
-
7/27/2019 Rhett StentsPlatelets
21/31
Aspirin: mechanism of action
-
7/27/2019 Rhett StentsPlatelets
22/31
Resistance to antiplatelet therapy
Resistance and differences in response to
antiplatelet medication has been known and
investigated in recent years. Clopidogrel is a prodrug that must be
converted to the active form by
cytochrome-p450 enzymes
-
7/27/2019 Rhett StentsPlatelets
23/31
0
20
40
60
80
100
Aggregation(%)
80 9
37 20
5.0
4.0
3.0
2.0
1.0
0
1.9 0.7
2.7 1.0
Platelet aggregation
4 hours post clopidogrel*
*450 mg PO (P=0.0002); **P=0.15
Nonresponders (25%)
14C
O2exhaled/h(%)
Clopidogrel Nonresponsiveness
Correlation with CYP3A4 Enzyme Activity
Lau WC et al. J Am Coll Cardiol. 2003;41:225A.
Responders (75%)
CYP3A4** activity
-
7/27/2019 Rhett StentsPlatelets
24/31
Major questions
How do we test antiplatelet therapy
response?
When (If) to stop antiplatelet therapy?
When to restart?
How much to restart: maintenance dose v
loading dose?
What happens after 2 and 12months?
-
7/27/2019 Rhett StentsPlatelets
25/31
Platelet Function Monitoring
Clinical tests: Bleeding time , Platelet Funcion
Assay-100, platelet aggregometry and the TEG
Thromboelastogram: advantage of being able tomonitor ASA and thienopyridines and other
GPIIb/IIIa inhibitors
Gurbel PA, Becker RC, et al. Platelet Function Monitoring in Patients with Coronary Artery Disease. J Am
Coll Cardiol 2007; 50(19): 1822-1834. Review.
-
7/27/2019 Rhett StentsPlatelets
26/31
What happened to Mr. Smyth?
Surgeons will not like idea of continuing
antiplatelet medications.
When the surgeon was asked to considermaintaining at least the ASA, he refused.
He did accepted restarting ASA the same
day post op and the clopidogrel 48 hrs later.
-
7/27/2019 Rhett StentsPlatelets
27/31
What happened to Mr. Smyth?
Surgery proceeded without incident and he was
discharged after a uneventful hospital course.
He was given aspirin 81mg chewable in house. It is unknown when (or if) he restarted the
clopidogrel.
Follow-up phone call showed a disconnected
number
-
7/27/2019 Rhett StentsPlatelets
28/31
Conclusions
Drug Eluting stents:
Delay surgery for 12
months if possible tocomplete therapy
Continue ASA and
restart clopidogrel
ASAP
Bare Metal Stents:
Delay for 2 months
Continue ASA andrestart clopidogrel
ASAP
Memorial Hermann Hospital: UT system proposal
-
7/27/2019 Rhett StentsPlatelets
29/31
Perioperative management of antiplatelet agents in
noncardiac surgery.
Eur J Anaesthesiol. 2009 Mar;26(3):181-7. Links
Llau JV, Lopez-Forte C, Sapena L, Ferrandis R.
Department of Anaesthesiology and Critical Care
Medicine, University Clinic Hospital, Valencia, Spain.
https://webmail.uth.tmc.edu/owa/UrlBlockedError.aspxhttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Llau%2520JV%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Lopez-Forte%2520C%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Sapena%2520L%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Ferrandis%2520R%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Ferrandis%2520R%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Sapena%2520L%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Lopez-Forte%2520C%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Lopez-Forte%2520C%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Lopez-Forte%2520C%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/redir.aspx?C=6825d4368d4a4ecb968e59362d843899&URL=http%3a%2f%2fwww.ncbi.nlm.nih.gov%2fsites%2fentrez%3fDb%3dpubmed%26Cmd%3dSearch%26Term%3d%2522Llau%2520JV%2522%255BAuthor%255D%26itool%3dEntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlushttps://webmail.uth.tmc.edu/owa/UrlBlockedError.aspx -
7/27/2019 Rhett StentsPlatelets
30/31
Up and coming research
Dr. Ali Denktas and Dr. Evan Pivalizza
Safety Implications of Patients receiving Preoperative Antiplatelet therapy
with Clopidgrel and/or Aspirin:Investigation of Thrombelastograph PlateletMapping to objectively assess Platelet Inhibition and subsequent use to guide
individual patient management. PI Evan Pivalizza, CO-PI Davide Cattano.
Perioperative management of antiplatelet therapy (Clopidogrel);
retrospective chart review. PI Ali Denktas, CO-PIDavide Cattano.
-
7/27/2019 Rhett StentsPlatelets
31/31
Thank you!