Dual antiplatelet therapy up to the time of non-elective coronary artery bypass grafting with prophylactic platelet transfusion: is it safe?

Platelet inhibitor withdrawal and outcomes after coronary artery surgery: an individual patient data meta-analysis

OBJECTIVES

To evaluate the association between guideline-conforming as compared to shorter than recommended withdrawal period of P2Y12 receptor inhibitors prior to isolated on-pump coronary artery bypass grafting (CABG) and the incidence of severe bleeding and ischaemic events. Randomized controlled trials are lacking in this field.

METHODS

We searched PUBMED, Embase and other suitable databases for studies including patients on P2Y12 receptor inhibitors undergoing isolated CABG and reporting bleeding and postoperative ischaemic events from 2013 to March 2024. The primary outcome was incidence of Bleeding Academic Research Consortium type 4 (BARC-4) bleeding defined as any of the following: perioperative intracranial bleeding, reoperation for bleeding, transfusion of ≥5 units of red blood cells, chest tube output of ≥2 l. The secondary outcome was postoperative ischaemic events according to the Academic Research Consortium 2 Consensus Document. Patient-level data provided by each observational trial were synthesized into a single dataset and analysed using a 2-stage IPD-MA.

RESULTS

Individual data of 4837 patients from 7 observational studies were synthesized. BARC-4 bleeding, 30-day mortality and postoperative ischaemic events occurred in 20%, 2.6% and 5.2% of patients. After adjusting for EuroSCORE II and cardiopulmonary bypass time, guideline-conforming withdrawal was associated with decreased BARC-4 bleeding risk in patients on clopidogrel [adjusted odds ratio (OR) 0.48; 95% confidence intervals (CI) 0.28-0.81; P = 0.006] and a trend towards decreased risk in patients on ticagrelor (adjusted OR 0.48; 95% CI 0.22-1.05; P = 0.067). Guideline-conforming withdrawal was not significantly associated with 30-day mortality risk (clopidogrel: adjusted OR 0.70; 95% CI 0.30-1.61; ticagrelor: adjusted OR 0.89; 95% CI 0.37-2.18) but with decreased risk of postoperative ischaemic events in patients on clopidogrel (clopidogrel: adjusted OR 0.50; 95% CI 0.30-0.82; ticagrelor: adjusted OR 0.78; 95% CI 0.45-1.37). BARC-4 bleeding was associated with 30-day mortality risk (adjusted OR 4.76; 95% CI 2.67-8.47; P < 0.001).

CONCLUSIONS

Guideline-conforming preoperative withdrawal of ticagrelor and clopidogrel was associated with a 50% reduced BARC-4 bleeding risk when corrected for EuroSCORE II and cardiopulmonary bypass time but was not associated with increased risk of 30-day mortality or postoperative ischaemic events.

Double the Trouble - One Infarction After Another: A Case Report of Two Consecutive ST-Segment Elevation Myocardial Infarctions in Two Different Coronary Arteries

In multi-vessel coronary artery disease, concomitant ST-segment elevation myocardial infarction (STEMI) in simultaneous two culprit lesions have been rarely reported. In this regard, the recurrence in a short period of time of a STEMI in a different coronary artery is also rare. We describe the case of a 56-year-old male smoker, who was presented with an anterior STEMI. The coronary angiography demonstrated a significant lesion in the left main coronary (LMC) and an occlusion of the left anterior descending artery (LAD), and was referred for surgery. Four days later, he experienced symptoms of acute ischemia of the inferior territory. A newly formed culprit lesion of the circumflex artery (Cx) was detected and benefited from angioplasty. The patient expired the next day from sudden arrythmia. This case report shows two consecutive STEMI situations in separate coronary arteries, which commonly can occur in atherosclerotic patients with very poor prognosis.

Dual antiplatelet therapy before coronary artery bypass grafting in patients with myocardial infarction: a prospective cohort study

BACKGROUND

Dual antiplatelet therapy (DAPT) in patients with MI who are candidates for early coronary artery bypass grafting (CABG) can affect intraoperative and postoperative outcomes. Therefore, the aim of this study was to evaluate the effect of DAPT up to the day before CABG on the outcomes during and after surgery in patients with MI.

METHODS

In this prospective cohort study, 224 CABG candidate patients with and without MI were divided into two groups: (A) patients without MI who were treated with aspirin 80 mg/day before surgery (noMI-aspirin group; n = 124) and (B) patients with MI who were treated with aspirin 80 mg/day before surgery and clopidogrel (Plavix brand) at a dose of 75 mg/day (MI-DAPT group; n = 120). Dual or mono-antiplatelet therapy continued until the day before surgery. Patients were followed to assess in-hospital and 6-months outcomes.

RESULTS

The in-hospital mortality in MI-DAPT group was similar with noMI-aspirin group (OR 4.2; 95% CI 0.9-20.5; p = 0.071). The prevalence of CVA (p = 0.098), duration of hospital stay (p = 0.109), postoperative ejection fraction level (p = 0.693), diastolic dysfunction grade (p = 0.651) and postoperative PAP level (p = 0.0364) did not show difference between two groups. No mild or severe bleeding was observed in the patients. Six-month follow up showed that number of readmissions (p = 0.801), number of cases requiring angiography (p = 0.100), cases requiring re-PCI (p = 0.156), need for re-CABG (p > 0.999) and CVA (p > 0.999) did not differ between the two groups. During the 6-month follow-up, out-hospital mortality did not differ significantly between the two groups (p = 0.446).

CONCLUSIONS

A 6-month follow-up showed that DAPT with aspirin and clopidogrel before CABG in patients with MI has no effect on postoperative outcomes more than mono-APT with aspirin. Therefore, DAPT is recommended in the preoperative period for these patients.

Platelet transfusion for patients with platelet dysfunction: effectiveness, mechanisms, and unanswered questions

PURPOSE OF REVIEW

In this review, we discuss current clinical guidelines and potential underlying mechanisms regarding platelet transfusion therapy in patients at risk of bleeding, comparing management of patients with thrombocytopenia versus those with qualitative platelet disorders.

RECENT FINDINGS

Platelet transfusion therapy is highly effective in managing bleeding in patients with hypoproliferative thrombocytopenia. Clinical trials have demonstrated that platelet transfusion can be used at a lower trigger threshold and reduced platelet doses, and may be used therapeutically rather than prophylactically in some situations, although additional data are needed. In patients with inherited platelet disorders such as Glanzmann's Thrombasthenia or those with RASGRP2 mutations, platelet transfusion may be ineffective because of competition between transfused and endogenous platelets at the site of vascular injury. Successful management of these patients may require transfusion of additional platelet units, or mechanism-driven combination therapy with other pro-hemostatic agents. In patients on antiplatelet therapy, timing of transfusion and inhibitor mechanism-of-action are key in determining therapeutic success.

SUMMARY

Expanding our understanding of the mechanisms by which transfused platelets exert their pro-hemostatic function in various bleeding disorders will improve the appropriate use of platelet transfusion.

Thromboelastography Platelet Mapping—A Useful Preoperative Tool to Reduce Transfusion Requirement by Determining Timing of Coronary Artery Bypass Graft Surgery in Patients taking Dual Antiplatelet Medication: A Pilot Study from Eastern India

In this pilot study, we proposed an algorithm to use thromboelastography platelet mapping (TEG-PM) as an effective preoperative platelet function assessment tool in coronary artery bypass graft surgery (CABG) to reduce the transfusion requirement by determining timing of surgery in patients who are on dual antiplatelet therapy (DAPT). Total 15 elective CABG patients who were receiving DAPT were tested by TEG-PM assay after 72 hours’ stoppage of both medications. Four patients who had < 50% inhibition with agonists (arachidonic acid [AA] and adenosine diphosphate [ADP]) were operated within 24 hours of assay. Eight patients who had > 70% inhibition with AA/ADP, surgery was deterred till 48 hours, and 3 patients with > 50% but < 70% inhibition were operated within 24 hours after preoperative prophylactic platelet transfusion. Transfusion requirement was recorded and compared with the previous transfusion data for CABG cases operated without TEG-PM. Distribution of ADP inhibition was 67.54 ± 30.03% and AA inhibition was 60.69 ± 30.14%, showing a variable offset of the effect of both medications starting after 72 hours of cessation. Overall transfusion requirement was decreased by using TEG-PM algorithm. Preoperative platelet function testing to determine the timing of surgery by TEG-PM assay in DAPT-treated patients may be a useful strategy to reduce transfusion requirement in CABG.