Örebro University School of Medicine Degree project, 30 ECTS May 31st, 2018
Inadequate antiplatelet pre-treatment in patients undergoing acute thoracic
surgery. Risk for complications and cost.
Version 2
Author: Carolina Nordmark, Bachelor of Medicine Supervisor: Fredrik Calais, MD, PhD Örebro, Sweden
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Table of content
Abstract ... 3 Abbreviations ... 4 Introduction ... 5 Aim ... 7Material and Methods ... 7
Results ... 9 Discussion ... 11 Conclusion ... 12 Acknowledgement ... 12 Ethical considerations ... 12 References ... 14 Cover letter ... 16 Press release ... 17
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Abstract
Introduction Prior to percutaneous coronary intervention (PCI) guidelines recommend that patients with ST- elevation myocardial infarction (STEMI) receive dual antiplatelet therapy
(DAPT) consisting of P2Y12 inhibition and acetylsalicylic acid (aspirin). However, in rare
occasions, patients admitted with STEMI as preliminary diagnosis require acute thoracic
surgery and oral P2Y12 inhibitors increases the bleeding risk over several hours. Cangrelor is
an intravenous reversible P2Y12 antagonist with normal platelet function returning within 60
minutes and might therefore be an attractive alternative to oral P2Y12 inhibition.
Aim Firstly, to quantify P2Y12 pre-treatment with ticagrelor in patients undergoing acute thoracic surgery and the mortality and morbidity rate associated with DAPT prior to surgery. Secondly, to estimate cost-benefit differences between cangrelor and ticagrelor pre-treatment.
Material and Methods A descriptive cohort study using retrospective data. The inclusion criteria were patients undergoing acute thoracic surgery (≤ 24 hours) between January 2015 and December 2017, in the catchment area of Örebro University Hospital. Patients were stratified into groups depending on whether they had received pre-treatment with DAPT or not before surgery. Statistical analyses were made in SPSS and Excel.
Results A total of 50 patients were included. 8 patients received DAPT before surgery. There was no mortality in patients receiving DAPT but TIMI major bleeding was more frequent compared to the group with no pre-treatment. The DAPT group required numerically more units of platelets and plasma, however the result was not significant. Direct treatment costs for ticagrelor was 20.14 SEK (the dosage is 2 tablets) and cangrelor was 3 059 SEK.
Conclusions DAPT pre-treatment with ticagrelor was not associated with increased mortality but TIMI major bleeding was more frequent compared to the group with no pre-treatment. Direct treatment costs with cangrelor was higher compared to ticagrelor treatment. Further studies, with larger study samples, are needed to investigate complications associated with
P2Y12 pre-treatment in patients undergoing acute thoracic surgery.
Key words Dual antiplatelet therapy, ST-elevation myocardial infarction, bleeding complications, acute thoracic surgery
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Abbreviations
AAD - Acute aortic dissection type A ACS - Acute coronary syndrome ADP - Adenosine diphosphate Aspirin - Acetylsalicylic acid
CABG - Coronary artery bypass grafting DAPT - Dual antiplatelet therapy
ECC - Extracorporeal circulation Hb - Hemoglobin
MI - Myocardial infarction
NSTEMI - Non-ST segment elevation myocardial infarction PCI - Percutaneous coronary intervention
SCAAR - Swedish coronary angiography and angioplasty registry STEMI - ST- elevation myocardial infarction
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Introduction
Prior to percutaneous coronary intervention (PCI) guidelines recommend that patients with ST- elevation myocardial infarction (STEMI) receive dual antiplatelet therapy (DAPT)
consisting of P2Y12 inhibition and acetylsalicylic acid (aspirin) [1,2]. The most common
P2Y12 antagonist used for pre-treatment in Sweden is oral ticagrelor [3]. However, in rare
occasions, patients admitted with STEMI as preliminary diagnosis require acute thoracic
surgery and oral P2Y12 inhibitors increases the bleeding risk over several hours. Cangrelor is
an intravenous reversible P2Y12 antagonist with a fast-onset as well as a fast offset after stopped infusion, with normal platelet function returning within 60 minutes [4] and might therefore be an attractive alternative to oral P2Y12 inhibition.
Excessive bleeding is a large issue in cardiac surgery [5–7]. It is associated with complications such as increased morbidity, mortality and excessive costs. Impaired
hemostasis due to antithrombotic medication is a contributing factor. Other factors that may cause increased bleeding in surgery are acute operations, old age and low plasma
concentration of fibrinogen [6]. Examples of independent risk factors for reoperation are DAPT < 5 days before surgery, combined valve and coronary artery bypass operations and long extracorporeal circulation time [8]. Reoperation and an increase in transfusion
requirements are independently associated with increased risk of mortality and morbidity [9,10].
Ticagrelor is an oral reversible P2Y12 antagonist and has an onset of 30 minutes – 2 hours
and effect duration of 3-4 days [6,11]. There is no clinically available antidote to ticagrelor [6] and platelet concentrate do not improve adenosine diphosphate (ADP) – induced aggregation after discontinuation. The lack of effect of platelet concentrate can last for several days and it is possible that remaining ticagrelor redistribute to the transfused platelets [12]. Prior to elective or subacute major surgery, 5 days discontinuation of ticagrelor is recommended. However, studies found no significant difference in the incidence of major bleeding complications when discontinuation time was reduced up to 3 days. Another advantage of reduced discontinuation time is shorter length-of-stay. Nevertheless, discontinuation of ticagrelor increase the risk of thrombosis and thus time to surgery should be optimized [6].
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A retrospective observational study in Sweden, including Örebro University Hospital,
investigated DAPT pre-treatment in patients with acute coronary syndrome (ACS) undergoing coronary artery bypass grafting (CAGB). Patients pre-treated with ticagrelor had less major bleeding complications (BARC - CAGB 12.9 % vs. 17.6 %, p = 0.0024) and required fewer blood products compared to pre-treatment with clopidogrel. At discontinuation < 24 h before surgery, patients receiving ticagrelor had larger blood loss and required more blood products
[13]. Patients undergoing CABG ˃ 5 days after discontinuation of P2Y12 inhibitors had longer
lengths of stay in hospital compared to discontinuation of 72 h to 5 days [14]. Patients with acute aortic dissection type A (AAD) pre-treated with DAPT had a higher rate of bleeding (5.6 ± 4.1 L vs. 3.3 ± 4.8 L, p < 0.001) compared with no pre-treatment. Furthermore, reoperation was pronounced in patients receiving DAPT compared to aspirin alone or no DAPT (37 % vs. 19 %, p = 0.02) [15].
Montalescot G et al found [16] no difference in ischemic events between pre-hospital and in-hospital administration with ticagrelor in patients with acute STEMI. Pre-in-hospital
administration could be safe but pre-PCI coronary reperfusion was not improved in the study.
In the CHAMPION trials, cangrelor compared to clopidogrel reduced mortality, stent
thrombosis, myocardial infarction (MI) and ischemia-driven revascularization (6.0 % vs. 7.4 %, OR 0.80 [95 % CI 0.65 - 0.98]) in patients with prior MI at 48 hours post-PCI. There was no significant increase in transfusions or severe bleeding [17,18]. However, cangrelor versus placebo did not reduce ischemic events but stent thrombosis was reduced [19]. In contrast, cangrelor was not superior to clopidogrel in reducing ischemic events at 48 hours and in patients receiving cangrelor minor bleeding was more frequent [20].
The PLATO trial found that ticagrelor was superior clopidogrel in reducing MI, death and stroke (9.8 % vs. 11.7 %, HR 0.84 [95 % CI 0.77 - 0.92]) in patients with ACS with or
without STEMI. There was no difference in major bleeding between the two groups but major bleeding not associated with CAGB, was increased in patients receiving ticagrelor [21]. In a study from the SWEDEHEART registry, ticagrelor compared with clopidogrel treatment at discharge was associated with a lower risk of MI, death and stroke. However, ticagrelor was associated with a higher risk of bleeding [22].
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Aim
Firstly, to quantify P2Y12 pre-treatment with ticagrelor in patients undergoing acute thoracic
surgery and the mortality and morbidity rate associated with DAPT prior to surgery.
Secondly, to estimate cost-benefit differences between cangrelor and ticagrelor pre-treatment, taking in account direct treatment costs.
Material and Methods
A descriptive cohort study using retrospective data from medical records and the Swedish coronary angiography and angioplasty registry (SCAAR) and the Thoracic Surgical Register. Patients ID-number was extracted from SCAAR and the Thoracic Surgical Register and data was collected from the medical records. The inclusion criteria were patients undergoing acute thoracic surgery (≤ 24 hours) between January 2015 and December 2017, in the catchment area of Örebro University Hospital. Patients were stratified into groups depending on whether they had received pre-treatment with DAPT or not before surgery. The time interval was chosen to receive up-to-date data.
Statistical analyses were made in Excel and SPSS Statistics version 22. A p-value of 0.05 was considered as significant. Mean value with standard deviation (SD) was used for description of normal distribution variables and median value with interquartile range (IQR) for non-normal distribution. Fisher’s exact test, Student’s t-test and Mann-Whitney U test were used for comparison between groups.
Bleeding complications was defined according to Thrombolysis in Myocardial Infarction (TIMI) risk score. If only one Hb-value was present, a normal hemoglobin - value (Hb-value) (117 g/L for women and 134 g/L for men) was estimated as baseline value. Mortality was defined as mortality before discharge from the hospital. Aspirin or ticagrelor treatment and anticoagulant treatment was included on the day of admission. Blood transfusion in mL were converted to units when necessary. Direct treatment costs were collected from the
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Exclusion criteria included missing data in medical records. This study aimed to describe contemporary care in Region Örebro County and therefore only patients in the catchment area were included.
Study Populations and reasons for exclusion are presented in Figure 1. 678 patients (from SCAAR) underwent acute angiography under the diagnosis of STEMI and received pre-treatment with DAPT, in 97 of those patients acute PCI was not performed following
angiography and these patients were screened for inclusion in the study. 2 patients underwent acute thoracic surgery and were included. According to the Thoracic Surgical Register, 86 patients underwent acute thoracic surgery. After exclusion we identified 48 patients who underwent acute thoracic surgery. In total 50 patients that underwent acute thoracic surgery were included.
Abbreviations: DAPT: dual antiplatelet therapy; NSTEMI: non-ST segment elevation myocardial infarction; SCAAR: the Swedish coronary angiography and angioplasty registry; STEMI: ST- elevation myocardial infarction
Figure 1.
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Results
A total of 50 patients were included from SCAAR and the Thoracic Surgical Register and 8 of them received DAPT before surgery. Baseline characteristics and surgical parameters of the two surgery groups are shown in Table 1. There was no significant difference in baseline characteristic between the two groups. Aortic aneurysm surgery was most frequent in the surgery group with no DAPT pre-treatment and CABG with extracorporeal circulation (ECC) in patients receiving DAPT prior to surgery.
Outcomes are presented in Table 2. There was no mortality in patients receiving DAPT. Bleeding complications was mainly associated with surgery in both groups. In the DAPT group, TIMI major bleeding was significantly more frequent (p = 0.035) compared to the group with no pre-treatment. The DAPT group required numerically more units of platelets
Abbreviations: CABG: coronary artery bypass grafting; DAPT: dual antiplatelet therapy; ECC: extracorporeal circulation; MI: myocardial infarction;SD: standard deviation
Table 1.
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and plasma, however the result was not significant. In the surgery group with no DAPT pre-treatment 7 patients only had one Hb-value was present and therefore a normal Hb-value was estimated as baseline value. In the same group, there were also 2 patients that received unknown amount of red blood cells and plasma in addition to an exact amount of blood products.
Direct treatment costs for ticagrelor was 20.14 SEK (the dosage is 2 tablets) and cangrelor was 3 059 SEK. Treatment costs with ticagrelor for all 678 patients undergoing acute angiography under the diagnosis of STEMI was 27 309.84 SEK, between January 2015 and December 2017. Estimated treatment cost with cangrelor for 678 patients would be 2 074 002 SEK. There was no difference in hospitalization between patients receiving DAPT vs. no DAPT pre-treatment prior to surgery, the median length of stay was 14 days in both surgery groups.
Table 2. Outcome
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Discussion
A small number of patients receiving pre-treatment with DAPT underwent acute thoracic
surgery. In this study, complications associated with P2Y12 pre-treatment with ticagrelor in
patients undergoing acute thoracic surgery was minor. However, TIMI major bleeding was more frequent compared to the group with no pre-treatment. For example, of 678 patients undergoing acute angiography under the diagnosis of STEMI only 2 patients received pre-treatment with DAPT and underwent acute thoracic surgery. Ticagrelor pre-pre-treatment was not associated with increased mortality. However, larger study samples are needed.
In the DAPT pre-treated surgery group, CABG surgery was most common, but in the surgery group with no DAPT pre-treatment, aortic aneurysm surgery was most frequent. This may explain some of the mortality in this group, as this is a severe condition with high mortality.
A limitation was the small study sample. Many patients were excluded, and the results were not significant due to both surgery groups (DAPT respectively no DAPT pre-treatment) were too small to compare. Another limitation was that some of the patients from the Thoracic Surgical Register underwent several types of valve replacement that did not indicate pre-treatment with DAPT and therefore might affect the results. Furthermore, since it is a
retrospective study it is plausible that some data is misinterpreted, for example Hb-value and blood transfusions were sometimes estimated respectively calculated into other measures. In addition, the study did not examine cangrelor, as it is not routine treatment at Örebro
University Hospital, and only direct treatment costs are presented.
DAPT pre-treatment at the Örebro University Hospital has been investigated in a retrospective study before [13]. However, it examined ticagrelor with clopidogrel
pre-treatment in patients with ACS undergoing CAGB and in this study ticagrelor was compared to no DAPT pre-treatment in patients undergoing CABG in addition to other types of acute surgery. Hansson EC et al [13] found less major bleeding complications and a need of fewer blood products in patients receiving ticagrelor compared to pre-treatment with clopidogrel. Both ticagrelor and clopidogrel are oral P2Y12 inhibitors so therefore the results are not comparable with ticagrelor or no ticagrelor pre-treatment.
In some previous studies, ticagrelor was not included and therefore the results may not be applicable to all patients with prior MI. Though cangrelor is more expensive than ticagrelor, it
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has the benefit of fast offset after stopped infusion resulting in shorter discontinuation to acute thoracic surgery and reduced bleeding complications. This can possibly reduce mortality and morbidity, length of stay in hospital and potentially be more cost-effective than routine treatment with ticagrelor. However, in this study there was no difference in length of stay in the two surgery groups and the higher amount of blood transfusions in the DAPT pre-treated surgery group was not significant. Nevertheless, there was no mortality in the DAPT group and TIMI major bleeding was more frequent.
Further studies, with larger study samples, are needed to investigate complications associated
with P2Y12 pre-treatment in patients undergoing acute thoracic surgery.
Conclusion
In this study, DAPT pre-treatment with ticagrelor was not associated with increased mortality but TIMI major bleeding was significantly more frequent compared to the group with no pre-treatment. Direct treatment costs with cangrelor was higher compared to ticagrelor pre-treatment. Further studies, with larger study samples, are needed to investigate complications associated
with P2Y12 pre-treatment in patients undergoing acute thoracic surgery.
Acknowledgement
I would like to express my very great appreciation to Örjan Friberg MD, PhD; Anders Magnusson BSc; and Lena Böörs Head of Department of PCI for their commitment in this project. Thank you very much!
Ethical considerations
The study was a quality management program performed at the Department of Cardiology, Örebro University Hospital. Pre-treatment with DAPT is routine treatment in patients with STEMI. In rare occasions patients need acute thoracic surgery and DAPT increases the bleeding risk, delays surgery and results in longer length of stay in hospital. Therefore, there
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is a need for investigating the magnitude of P2Y12 pre-treatment problem in relation to acute
thoracic surgery.
Data were de-identified so that health information of an individual could not be identified. Patients’ ID-number from SCAAR and the Thoracic Surgical Register were safety kept locked in at the Department of Cardiology.
Since this was a quality management program ethical approval was not needed. However, the study can not be published and therefore the results are only beneficial for patients in the catchment area of Örebro University Hospital. If a new study, based on the findings of this study, will be conducted an ethical approval must be applied for. A new study with larger study samples could possibly provide better treatment for a larger number of patients.
Reading patients’ medical records and SCAAR data is to compromise their integrity. However, the study has the potential benefit of better and possibly more cost-effective treatment for the patient group.
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References
1. Valgimigli M, Bueno H, Byrne RA, Collet J-P, Costa F, Jeppsson A, et al. 2017
ESC focused update on dual antiplatelet therapy in coronary artery disease developed in collaboration with EACTS. Eur J Cardio-Thorac Surg Off J Eur Assoc Cardio-Thorac Surg. 2018 Jan 1;53(1):34–78.
2. Abtan J, Steg PG, Stone GW, Mahaffey KW, Gibson CM, Hamm CW, et al.
Efficacy and Safety of Cangrelor in Preventing Periprocedural Complications in Patients With Stable Angina and Acute Coronary Syndromes Undergoing Percutaneous Coronary
Intervention: The CHAMPION PHOENIX Trial. JACC Cardiovasc Interv. 2016 Sep 26;9(18):1905–13.
3. arsrapport-2016.pdf [Internet]. [cited 2018 Feb 1]. Available from:
http://www.ucr.uu.se/swedeheart/arsrapport-2016?task=document.viewdoc&id=923
4. Alexopoulos D, Pappas C, Sfantou D, Lekakis J. Cangrelor in Percutaneous
Coronary Intervention: Current Status and Perspectives. J Cardiovasc Pharmacol Ther. 2018 Jan;23(1):13–22.
5. Dyke C, Aronson S, Dietrich W, Hofmann A, Karkouti K, Levi M, et al.
Universal definition of perioperative bleeding in adult cardiac surgery. J Thorac Cardiovasc Surg. 2014 May;147(5):1458–1463.e1.
6. Hansson EC, Jeppsson A. Platelet inhibition and bleeding complications in
cardiac surgery: A review. Scand Cardiovasc J SCJ. 2016 Dec;50(5–6):349–54.
7. Stone GW, Clayton TC, Mehran R, Dangas G, Parise H, Fahy M, et al. Impact
of major bleeding and blood transfusions after cardiac surgery: analysis from the Acute Catheterization and Urgent Intervention Triage strategY (ACUITY) trial. Am Heart J. 2012 Mar;163(3):522–9.
8. Fröjd V, Jeppsson A. Reexploration for Bleeding and Its Association With
Mortality After Cardiac Surgery. Ann Thorac Surg. 2016 Jul;102(1):109–17.
9. Vivacqua A, Koch CG, Yousuf AM, Nowicki ER, Houghtaling PL, Blackstone
EH, et al. Morbidity of Bleeding After Cardiac Surgery: Is It Blood Transfusion, Reoperation for Bleeding, or Both? Ann Thorac Surg. 2011 Jun 1;91(6):1780–90.
10. Ranucci M, Bozzetti G, Ditta A, Cotza M, Carboni G, Ballotta A. Surgical
reexploration after cardiac operations: why a worse outcome? Ann Thorac Surg. 2008 Nov;86(5):1557–62.
11. Sibbing D, Kastrati A, Berger PB. Pre-treatment with P2Y12 inhibitors in ACS
patients: who, when, why, and which agent? Eur Heart J. 2016 21;37(16):1284–95.
12. Hansson EC, Malm CJ, Hesse C, Hornestam B, Dellborg M, Rexius H, et al.
Platelet function recovery after ticagrelor withdrawal in patients awaiting urgent coronary surgery. Eur J Cardio-Thorac Surg Off J Eur Assoc Cardio-Thorac Surg. 2017 01;51(4):633– 7.
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13. Hansson EC, Jidéus L, Åberg B, Bjursten H, Dreifaldt M, Holmgren A, et al.
Coronary artery bypass grafting-related bleeding complications in patients treated with ticagrelor or clopidogrel: a nationwide study. Eur Heart J. 2016 Jan 7;37(2):189–97.
14. Russo JJ, James TE, Ruel M, Dupuis J-Y, Singh K, Goubran D, et al. Ischemic
and bleeding outcomes after coronary artery bypass grafting among patients initially treated with a P2Y12 receptor antagonist for acute coronary syndromes: Insights on timing of discontinuation of ticagrelor and clopidogrel prior to surgery. Eur Heart J Acute Cardiovasc Care. 2018 Jan 1;2048872617740832.
15. Chemtob RA, Moeller-Soerensen H, Holmvang L, Olsen PS, Ravn HB.
Outcome After Surgery for Acute Aortic Dissection: Influence of Preoperative Antiplatelet Therapy on Prognosis. J Cardiothorac Vasc Anesth. 2017 Apr 1;31(2):569–74.
16. Montalescot G, van ’t Hof AW, Lapostolle F, Silvain J, Lassen JF, Bolognese L,
et al. Prehospital ticagrelor in ST-segment elevation myocardial infarction. N Engl J Med. 2014 Sep 11;371(11):1016–27.
17. Eisen A, Harrington RA, Stone GW, Steg PG, Gibson CM, Hamm CW, et al.
Cangrelor compared with clopidogrel in patients with prior myocardial infarction - Insights from the CHAMPION trials. Int J Cardiol. 2018 Jan 1;250:49–55.
18. Bhatt DL, Stone GW, Mahaffey KW, Gibson CM, Steg PG, Hamm CW, et al.
Effect of platelet inhibition with cangrelor during PCI on ischemic events. N Engl J Med. 2013 Apr 4;368(14):1303–13.
19. Bhatt DL, Lincoff AM, Gibson CM, Stone GW, McNulty S, Montalescot G, et
al. Intravenous platelet blockade with cangrelor during PCI. N Engl J Med. 2009 Dec 10;361(24):2330–41.
20. Harrington RA, Stone GW, McNulty S, White HD, Lincoff AM, Gibson CM, et
al. Platelet inhibition with cangrelor in patients undergoing PCI. N Engl J Med. 2009 Dec 10;361(24):2318–29.
21. Wallentin L, Becker RC, Budaj A, Cannon CP, Emanuelsson H, Held C, et al.
Ticagrelor versus clopidogrel in patients with acute coronary syndromes. N Engl J Med. 2009 Sep 10;361(11):1045–57.
22. Sahlén A, Varenhorst C, Lagerqvist B, Renlund H, Omerovic E, Erlinge D, et al.
Outcomes in patients treated with ticagrelor or clopidogrel after acute myocardial infarction: experiences from SWEDEHEART registry. Eur Heart J. 2016 Nov 21;37(44):3335–42.
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Cover letter
Dear Editor, 2018-05-31
Please, consider the enclosed manuscript entitled “Inadequate antiplatelet pre-treatment in patients undergoing acute thoracic surgery. Risk for complications and cost.” for
publication in XX.
This retrospective cohort study quantifies P2Y12 pre-treatment with ticagrelor in patients
undergoing acute thoracic surgery and the mortality and morbidity rate associated with DAPT prior to surgery in patients at the Örebro University Hospital. In our study there was no mortality in patients receiving DAPT. TIMI major bleeding was significantly more frequent compared to the group with no pre-treatment. Direct treatment costs with cangrelor was higher compared to ticagrelor treatment.
The study has the potential benefit of better and possibly more cost-effective treatment for the patient group by investigating risk for complications and cost of ticagrelor pre-treatment There has been no previous study examining ticagrelor vs. no ticagrelor pre-treatment in patients undergoing acute thoracic surgery at the Örebro University Hospital before. I believe that this manuscript is appropriate for publication because there is a need to investigate the
potential P2Y12 pre-treatment problem in relation to acute thoracic surgery.
We confirm that this work has not been published elsewhere, nor is it currently under
consideration for publication elsewhere. We have no conflicts of interest to disclose.
Thank you for your consideration of this manuscript.
Yours sincerely,
Carolina Nordmark, Bachelor of Medicine Örebro University
Örebro Sweden
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Press release
Vid hjärtinfarkt får patienterna en läkemedelskombination av acetylsalicylsyra och tikagrelor för att hämma trombocytaggregationen och trombocytaktivering. Läkemedlen ges innan röntgenundersökning av hjärtats blodkärl, så kallad angiografi, genomförs. Ibland behöver dock några patienter genomgå akut thorakal operation och acetylsalicylsyra och tikagrelor ökar blödningsrisken, vilket gör att man inte bör operera genast. De rekommendationer som finns är att det ska gå 5 dagar mellan det att behandlingen avslutades innan man opererar.
Tikagrelor ges i tablettform men det finns ett annat läkemedel som heter cangrelor som ges intravenöst. Fördelen med cangrelor är att det dels har en snabbare effekt dels kan tillförseln av läkemedlet avbrytas snabbt. Redan inom 60 minuter återfås en normal trombocytfunktion vilket möjliggör operation mycket tidigare jämfört med tikagrelor. Dock är cangrelor
betydligt dyrare än tikagrelor och idag används det inte vid Örebro Universitetssjukhus.
Studien undersökte 50 patienter som opererades akut under perioden 2015–2017 vid Örebro Universitetssjukhus. Av dessa hade 8 patienter fått förbehandling med acetylsalicylsyra och tikagrelor. Ingen av dem som hade fått förbehandling avled under vårdtillfället men däremot var stor blödningskomplikation vanligare. Läkemedelskostnad för cangrelor var högre jämfört med tikagrelor. Fler studier med en större studiepopulation behövs för att undersöka möjliga risker med förbehandling i relation till akut thorakal operation för att kunna bedöma
