Abstract

BACKGROUND In some randomized controlled trials (RCTs), transradial (TRA) compared with transfemoral access (TFA) was associated with lower mortality in coronary artery disease patients undergoing invasive management. We analyzed the effects of TRA versus TFA across multicenter RCTs and whether these associations are modified by patient or operator characteristics. METHODS We performed an individual patient data meta-analysis of multicenter RCTs comparing TRA versus TFA among patients undergoing coronary angiography with or without percutaneous coronary intervention (PCI) (PROSPERO; CRD42018109664). The primary outcome was all-cause mortality and the co-primary outcome was major bleeding at 30 days. The primary analysis was conducted by one-stage mixed-effects models based on the intention-to-treat cohort. The impact of access-site on mortality and major bleeding was further assessed by multivariable analysis. The relationship among access-site, bleeding, and mortality was investigated by natural effect model mediation analysis with multivariable adjustment. RESULTS A total of 21,600 patients (TRA=10,775 vs. TFA=10,825) from 7 RCTs were included. Median age was 63.9 years, 31.9% were female, 95% presented with acute coronary syndrome (ACS), and 75.2% underwent PCI. All-cause mortality (1.6% vs. 2.1%; HR 0.77, 95% CI 0.63-0.95, p=0.012) and major bleeding (1.5% vs. 2.7%; OR 0.55, 95% CI 0.45- 0.67, p<0.001) were lower with TRA. Subgroup analyses for mortality showed consistent results, except for baseline hemoglobin ((pinteraction)=0.033), indicating that the benefit of TRA was substantial in patients with significant anemia, while it was not significant in patients with milder or no baseline anemia. After adjustment, TRA remained associated with 24% and 51% relative risk reduction of all-cause mortality and major bleeding. A mediation analysis showed that the benefit of TRA on mortality was only partially driven by major bleeding prevention, and ancillary mechanisms are required to fully explain the causal association. CONCLUSIONS TRA is associated with lower all-cause mortality and major bleeding at 30 days, compared with TFA. The effect on mortality was driven by patients with anemia. The reduction in major bleeding only partially explains the mortality benefit.

Abstract

Dual antiplatelet therapy (DAPT), alongside percutaneous coronary intervention (PCI), is central to the prevention of ischemic events following acute coronary syndrome (ACS). However, response to therapy can vary due to several factors including CYP2C19 gene variation, which shows increased prevalence in East Asian populations. DAPT responsiveness can be assessed using techniques such as light transmission aggregometry (LTA), VerifyNow(®) and thromboelastography with the PlateletMapping(®) assay, and there is increasing focus on the utility of platelet function testing to guide individualized treatment. This systematic literature review of one English and three Chinese language databases was conducted to evaluate the evidence for the utility of thromboelastography in ACS/PCI in East Asia. The search identified 42 articles from the English language and 71 articles from the Chinese language databases which fulfilled the pre-determined inclusion criteria, including 38 randomized controlled trials (RCTs). The identified studies explored the use of thromboelastography compared to LTA and VerifyNow in monitoring patient responsiveness to DAPT, as well as predicting ischemic risk, with some studies suggesting that thromboelastography is better able to detect low DAPT response than LTA. Other studies, including one large RCT, described the use of thromboelastography in guiding the escalation of DAPT, with some evidence suggesting that such protocols reduce ischemic events without increasing the risk of bleeding. There was also evidence suggesting that thromboelastography can be used to identify individuals with DAPT hyporesponsiveness genotypes and could potentially guide treatment by adjusting therapy in patients depending on responsiveness.

Abstract

PURPOSE Iron supplementation has been evaluated in several randomized controlled trials (RCTs) for its potential to increase baseline hemoglobin and decrease red blood cell transfusion during cardiac surgery. This study's main objective was to evaluate the current evidence for iron administration in cardiac surgery patients. METHODS We searched MEDLINE, EMBASE, CENTRAL, Web of Science databases, and Google Scholar from inception to 19 November 2020 for RCTs evaluating perioperative iron administration in adult patients undergoing cardiac surgery. The RCTs were assessed using a risk of bias assessment and the quality of evidence was assessed using the grading of recommendations, assessments, development, and evaluations. RESULTS We reviewed 1,767 citations, and five studies (n = 554) met the inclusion criteria. The use of iron showed no statistical difference in incidence of transfusion (risk ratio, 0.86; 95% confidence interval, 0.65 to 1.13). Trial sequential analysis suggested an optimal information size of 1,132 participants, which the accrued information size did not reach. CONCLUSION The current literature does not support or refute the routine use of iron therapy in cardiac surgery patients. TRIAL REGISTRATION PROSPERO (CRD42020161927); registered 19 December 2019.

Abstract

BACKGROUND To assess the performance of the Academic Research Consortium High Bleeding Risk (ARC-HBR) criteria in stratifying the risk of bleeding and ischaemic events after percutaneous coronary intervention (PCI). METHODS MEDLINE, COCHRANE, Web of Sciences, and SCOPUS were searched for studies aimed at validating the ARC-HBR criteria in patients treated with PCI. The primary outcome measure of this meta-analysis was major bleeding. RESULTS The analysis included 10 studies encompassing 67,862 patients undergoing PCI; the HBR definition was fulfilled in 44.7% of the cases. The risk of major bleeding was significantly higher in HBR vs. Non-HBR group (RR, 2.56, 95% CI 2.28-2.89). The average C-statistic was 0.64 (95% CI 0.60-0.68), indicating modest discrimination. The risk of intracranial hemorrhage, gastrointestinal bleeding, fatal bleeding, ischaemic stroke, cardiac death and all-cause death was higher in HBR vs. Non-HBR group. Despite a higher incidence of myocardial infarction and stent thrombosis in patients deemed at HBR, the rate of target lesion revascularization was comparable between groups (RR, 1.01, 95% CI 0.88-1.16). The mean effect size for the cumulative incidence of major bleeding exceeded the HBR cut-off value of 4% for all major criteria except one, and for two out of six minor criteria, namely age ≥ 75 years and moderate CKD. CONCLUSION The ARC-HBR definition identifies patients at higher risk of major bleeding and other adverse cardiovascular events after PCI. Almost all major criteria, but also two of the minor criteria, were individually associated with rates of major bleeding above 4% thus fulfilling the definition of major HBR criteria.

Abstract

OBJECTIVE Thromboelastography (TEG) is diagnostic modality that analyzes real-time blood coagulation parameters. Clinically, TEG primarily allows for directed blood component resuscitation among patients with acute blood loss and coagulopathy. The utilization of TEG has been widely adopted in among other surgical specialties; however, its use in vascular surgery is less prominent. We aimed to provide an up-to-date review of TEG utilization in vascular and endovascular surgery. METHODS Using PRISMA guidelines, a literature review with the Medical Subject Headings (MeSH) terms "TEG and arterial events", "TEG and vascular surgery", "TEG and vascular", "TEG and endovascular surgery", "TEG and endovascular", "TEG and peripheral artery disease", "TEG and prediction of arterial events", "TEG and prediction of complications ", "TEG and prediction of thrombosis", "TEG and prediction of amputation", and "TEG and amputation" was performed in Cochrane and PubMed databases to identify all peer-reviewed studies of TEG utilization in vascular surgery, written between 2000-2021 in the English language. The free text and MeSH subheadings search terms included diagnosis, complications, physiopathology, surgery, mortality, and therapy to further restrict the articles. Studies were excluded if they were not in humans or pertaining to vascular or endovascular surgery. Additionally, case reports and studies with limited information regarding TEG utilization were excluded. Each study was independently reviewed by two researchers to assess for eligibility. RESULTS Of the 262 studies identified through the MeSH strategy, 15 studies met inclusion criteria and were reviewed and summarized. Literature on TEG utilization in vascular surgery spanned cerebrovascular disease (n=3), peripheral arterial disease (n=3), arteriovenous malformations (n=1), venous thromboembolic events (n=7), and perioperative bleeding and transfusion (n=1). In cerebrovascular disease, TEG may predict the presence and stability of carotid plaques, analyze platelet function before carotid stenting, and compare efficacy of antiplatelet therapy after stent deployment. In peripheral arterial disease, TEG has been used to predict disease severity and analyze the impact of contrast on coagulation parameters. In venous disease, TEG may predict hypercoagulability and thromboembolic events among various patient populations. Finally, TEG can be utilized in the postoperative setting to predict hemorrhage and transfusion requirements. CONCLUSIONS This systematic review provides an up-to-date summarization of TEG utilization in multiple facets of vascular and endovascular surgery.

Abstract

OBJECTIVES This systematic review aims to outline the evidence on the implementation of a non-point-of-care (non-point-of-care [POC]) haemostasis management protocol compared to experience-based practice in adult cardiac surgery. BACKGROUND Management of coagulopathy in cardiac surgery is complex and remains highly variable among centres and physicians. Although various guidelines recommend the implementation of a transfusion protocol, the literature on this topic has never been systematically reviewed. METHODS PubMed, Embase, Cochrane Library, and Web of Science were searched from January 2000 till May 2020. RESULTS A total of seven studies (one randomised controlled trial [RCT], one prospective cohort study, and five retrospective studies) met the inclusion criteria. Among the six non-randomised, controlled studies, the risk of bias was determined to be serious to critical, and the one RCT was determined to have a high risk of bias. Five studies showed a significant reduction in red blood cells, fresh frozen plasma, and/or platelet transfusion after the implementation of a structural non-POC algorithm, ranging from 2% to 28%, 2% to 19.5%, and 7% to17%, respectively. One study found that fewer patients required transfusion of any blood component in the protocol group. Another study had reported a significantly increased transfusion rate of platelet concentrate in the haemostasis algorithm group. CONCLUSION Owing to the high heterogeneity and a substantial risk of bias of the included studies, no conclusion can be drawn on the additive value of the implementation of a cardiac-surgery-specific non-POC transfusion and haemostasis management algorithm compared to experience-based practice. To define the exact impact of a transfusion protocol on blood product transfusion, bleeding, and adverse events, well-designed prospective clinical trials are required.

Abstract

OBJECTIVES The benefits of preoperative intravenous (IV) iron treatment in cardiac surgery patients with preoperative anaemia or iron deficiency have not been well-established. We performed a systematic review and meta-analysis to determine the effects of treating preoperative anaemia or iron deficiency with IV iron in adult cardiac surgery patients. METHODS We searched Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval Systems Online and Excerpta Medica Database for randomized controlled trials (RCTs) and observational studies comparing IV iron to oral iron or no iron. We performed title and abstract, full-text screening, data extraction and risk of bias assessment independently and in duplicate. We pooled data using a random effects model and evaluated the overall quality of evidence. RESULTS We identified 4 RCTs and 7 observational studies. Pooled data from observational studies suggested a benefit of IV iron compared to no iron on mortality [relative risk 0.39, 95% confidence interval (CI) 0.23-0.65; P < 0.001, very low quality], units transfused per patient (mean difference -1.22, 95% CI -1.85 to -0.60; P < 0.001, very low quality), renal injury (relative risk 0.50, 95% CI 0.36-0.69; P < 0.001, very low quality) and hospital length of stay (mean difference -4.24 days, 95% CI -6.86 to -1.63; P = 0.001, very low quality). Pooled data from RCTs demonstrated a reduction in the number of patients transfused with IV iron compared to oral or no iron (relative risk 0.81, 95% CI 0.70-0.94; P = 0.005, moderate quality). The pooled estimates of effect from RCTs for mortality, hospital length of stay, units transfused per patient and renal injury were consistent in direction with observational studies. CONCLUSIONS This meta-analysis suggests that IV iron improves postoperative morbidity in adult cardiac surgery patients with preoperative anaemia or iron deficiency. A large, rigorous, placebo-controlled, double-blinded, multicentre trial is needed to clarify the role of IV iron in this patient population. CLINICAL TRIAL REGISTRATION International prospective register of systematic reviews ID Number CRD42019122844.

Abstract

BACKGROUND Anemia is common in cardiac surgery affecting 25-40% of patients and associated with increased blood transfusions, morbidity, mortality, and higher hospital costs. Higher rates of stroke, acute renal injury, and total number of adverse postoperative outcomes have also been reported to be associated with preoperative anemia. This systematic review assessed the current evidence for preoperative intravenous iron on major outcomes following cardiac surgery. METHODS Outcome measures included postoperative hemoglobin, transfusion rates, major adverse events, and mortality. The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and articles were identified using PubMed, Cochrane, CLINAHL, WOS, and EMBASE databases. Articles were included if they compared patients with and without preoperative anemia based on treatment with intravenous iron. Quality was assessed using Cochrane Risk of Bias Tool and Newcastle-Ottawa scale, and strength of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. RESULTS Of the articles reviewed, six met inclusion criteria. These included four randomized double-blind prospective cohort studies, one randomized non-blinded prospective study, and one non-randomized non-blinded prospective study with historical control. Across studies, 1,038 patients were enrolled. Two studies showed higher hemoglobin with iron therapy, and only one study showed significant differences in multiple outcomes such as transfusion and morbidity. CONCLUSIONS Given the paucity of studies and biases within them, the current evidence for treatment with intravenous iron prior to cardiac surgery is weak. More evidence is needed to support the administration of preoperative intravenous iron in cardiac surgery patients.

Abstract

Hypofibrinogenaemia during cardiac surgery may increase blood loss and bleeding complications. Viscoelastic point-of-care tests provide more rapid diagnosis than laboratory measurement, allowing earlier treatment. However, their diagnostic test accuracy for hypofibrinogenaemia has never been reviewed systematically. We aimed to systematically review their diagnostic test accuracy for the identification of hypofibrinogenaemia during cardiac surgery. Two reviewers assessed relevant articles from seven electronic databases, extracted data from eligible articles and assessed quality. The primary outcomes were sensitivity, specificity and positive and negative predictive values. A total of 576 articles were screened and 81 full texts were assessed, most of which were clinical agreement or outcome studies. Only 10 diagnostic test accuracy studies were identified and only nine were eligible (ROTEMdelta 7; TEG5000 1; TEG6S 1, n = 1820 patients) (ROTEM, TEM International GmbH, Munich, Germany; TEG, Haemonetics, Braintree, MA, USA). None had a low risk of bias. Four ROTEM studies with a fibrinogen threshold less than 1.5-1.6 g/l and FIBTEM threshold A10 less than 7.5-8 mm had point estimates for sensitivity of 0.61-0.88; specificity 0.54-0.94; positive predictive value 0.42-0.70; and negative predictive value 0.74-0.98 (i.e. false positive rate 30%-58%; false negative rate 2%-26%). Two ROTEM studies with higher thresholds for both fibrinogen (<2 g/l) and FIBTEM A10 (<9.5 mm) had similar false positive rates (25%-46%), as did the two TEG studies (15%-48%). This review demonstrates that there have been few diagnostic test accuracy studies of viscoelastic point-of-care identification of hypofibrinogenaemia in cardiac surgical patients. The studies performed so far report false positive rates of up to 58%, but low false negative rates. Further diagnostic test accuracy studies of viscoelastic point-of-care identification of hypofibrinogenaemia are required to guide their better use during cardiac surgery.

Abstract

BACKGROUND The ideal perioperative fluid resuscitation for ruptured abdominal aortic aneurysms (rAAA) is unknown. It has been shown in the trauma literature that a higher ratio of plasma and platelets to packed red blood cells confers a mortality benefit. There remains controversy whether this is true also in the ruptured aneurysm population. The objective of this study is to investigate the benefit of higher ratio of plasma to packed red blood cells in patients with ruptured abdominal aortic aneurysms. METHODS A health sciences librarian searched four electronic databases including PubMed, Embase, Cochrane, and ClinicalTrials.gov using concepts for the terms fluid resuscitation, survival, and ruptured abdominal aortic aneurysm. Two reviewers independently screened the studies that were identified through the search strategy and read in full any study that was potentially relevant. Papers were included if they compared mortality of patients with rAAA who received a higher ratio of plasma to other component therapy to patients who received a lower ratio. Risk of bias was assessed using the ROBINS-I validated tool and evidence quality was rated using the GRADE profile. No data synthesis or meta-analysis was planned or performed given the anticipated paucity of research on this topic and the high degree of heterogeneity of available studies. RESULTS Our search identified seven observational studies to be included in this review. Of these seven studies, three found an associated decrease in mortality with a higher ratio of plasma to packed red blood cells and the remaining four found no significant difference. The overall risk of bias was serious and the evidence quality was very low. CONCLUSIONS Overall, the available studies would suggest that for patients that have undergone open surgery for a ruptured abdominal aortic aneurysm, mortality rates tend to decrease when the amount of plasma transfused perioperatively is similar to the amount of packed red blood cells. However, this is very low-quality evidence based solely off of highly heterogenous observational studies and further research is warranted.