Platelet quiescence in patients with acute coronary syndrome undergoing coronary artery bypass graft surgery

BACKGROUND: The optimal antiplatelet strategy for patients with acute coronary syndromes who require coronary artery bypass surgery remains unclear. While a more potent antiplatelet regimen will predispose to perioperative bleeding, it is hypothesized that through “platelet quiescence,” ischemic protection conferred by such therapy may provide a net clinical benefit. METHODS AND RESULTS: We compared patients undergoing coronary artery bypass surgery who were treated with a more potent antiplatelet inhibition strategy with those with a less potent inhibition through a meta-analysis. The primary outcome was all-cause mortality after bypass surgery. The analysis identified 4 studies in which the antiplatelet regimen was randomized and 6 studies that were nonrandomized. Combining all studies, there was an overall higher mortality with weaker strategies compared with more potent strategies (odds ratio, 1.38; 95% CI, 1.03–1.85; P=0.03). CONCLUSIONS: Our findings support the concept of platelet quiescence, in reducing mortality for patients with acute coronary syndrome requiring coronary artery bypass surgery. This suggests the routine up-front use of potent antiplatelet regimens in acute coronary syndrome, irrespective of likelihood of coronary artery bypass graft

The Current Role of Viability Imaging to Guide Revascularization and Therapy Decisions in Patients With Heart Failure and Reduced Left Ventricular Function

This review describes the current evidence and controversies for viability imaging to direct revascularization decisions and the impact on patient outcomes. Balancing procedural risks and possible benefit from revascularization is a key question in patients with heart failure of ischemic origin (IHF). Different stages of ischemia induce adaptive changes in myocardial metabolism and function. Viable but dysfunctional myocardium has the potential to recover after restoring blood flow. Modern imaging techniques demonstrate different aspects of viable myocardium; perfusion (single-photon emission computed tomography [SPECT], positron emission tomography [PET], cardiovascular magnetic resonance [CMR]), cell metabolism (PET), cell membrane integrity and mitochondrial function (201Tl and 99mTc-based SPECT), contractile reserve (stress echocardiography, CMR) and scar (CMR). Observational studies suggest that patients with IHF and significant viable myocardium may benefit from revascularization compared with medical treatment alone but that in patients without significant viability, revascularization appears to offer no survival benefit or could even worsen the outcome. This was not supported by 2 randomized trials (Surgical Treatment for Ischemic Heart Failure [STICH] and PET and Recovery Following Revascularization [PARR] -2) although post-hoc analyses suggest that benefit can be achieved if decisions had been strictly based on viability imaging recommendations. Based on current evidence, viability testing should not be the routine for all patients with IHF considered for revascularization but rather integrated with clinical data to guide decisions on revascularization of high-risk patients with comorbidities.Peer reviewe

Patient Decision Aids for Aortic Stenosis and Chronic Coronary Artery Disease: A Systematic Review and Meta-Analysis

Aim Shared decision-making is recommended for patients considering treatment options for severe aortic stenosis (AS) and chronic coronary artery disease (CAD). This review aims to systematically identify and assess patient decision aids (PtDAs) for chronic CAD and AS and evaluate the international evidence on their effectiveness for improving the quality of decision-making. Methods and Results Five databases (Cochrane, CINAHL, Embase, MEDLINE, PsycInfo), clinical trial registers and 30 PtDA repositories/websites were searched from 2006 to March 2023. Screening, data extraction and quality assessments were completed independently by multiple reviewers. Meta-analyses were conducted using Stata statistical software. Eleven AS and 10 CAD PtDAs were identified; seven were less than five years old. Over half the PtDAs were web-based and the remainder paper-based. One AS and two CAD PtDAs fully/partially achieved international PtDA quality criteria. Ten studies were included in the review; four reported on the development/evaluation of AS PtDAs and six on CAD PtDAs. Most studies were conducted in the USA with White, well-educated, English-speaking participants. No studies fulfilled all quality criteria for reporting PtDA development and evaluation. Meta-analyses found that PtDAs significantly increased patient knowledge compared to ‘usual care’ (mean difference:0.620; 95%CI 0.396, 0.845, p Conclusion Patients who use PtDAs when considering treatments for AS or chronic CAD are likely to be better informed than those who do not. Existing PtDAs may not meet the needs of people with low health literacy levels as they are rarely involved in their development

Dual antiplatelet therapy (PEGASUS) vs. dual pathway (COMPASS): a head-to-head in vitro comparison

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is prescribed for 1-year after myocardial infarction. Two clinical strategies are considered at 1-year: continuation of DAPT or “Dual Pathway” (DP), using aspirin and rivaroxaban. No head-to-head comparative studies exist. In our in-vitro study, 24 samples of donor blood were treated with clinically proven concentrations of 5 antithrombotic regimens: aspirin, ticagrelor, rivaroxaban, DAPT, and DP. Thrombosis was analyzed using the Total Thrombus Analysis System (T-TAS) to measure both antiplatelet and anticoagulant effects. Flow cytometry was performed to quantify platelet activation. DAPT was the most potent antiplatelet regimen, delaying thrombus onset (p < .0001) and reducing thrombogenicity (p < .0001), relative to control. DP did not delay thrombus formation relative to aspirin alone (p = .69). DP was the most potent anticoagulant regimen, delaying thrombus onset (p < .0001) and reducing thrombogenicity (p < .0001), relative to control. DP showed synergistic antithrombotic effects by delaying thrombus onset (p < .0001) and reducing thrombogenicity (p = .0003), relative to rivaroxaban alone. Flow cytometry showed only DAPT (p = .0023) reduced platelet activation. DP treatment demonstrated synergistic antithrombotic effects over rivaroxaban alone, but no additional antiplatelet synergism over aspirin alone

Impact of trainee involvement on patient radiation exposure and contrast volumes during invasive cardiac procedures

Purpose: The impact of cardiology fellows (CFs) and interventional cardiology fellows (ICFs) on patient radiation and contrast exposure during diagnostic coronary angiography and percutaneous coronary intervention is unknown. Methods: Between 2011 and 2014, 16,175 cases were retrospectively assessed involving 27 CFs, 22 ICFs and 24 staff as primary operators. Results: During diagnostic coronary angiography, ICFs administered the lowest radiation dose (5,648±5,523 cGy*cm2; 1.30 ± 1.27 mSv)—achieving 22% less radiation than the staff (6,889±4,294 cGy*cm2; 1.58 ± 0.99 mSv) and 36% less than CFs (7,700±6,751 cGy*cm2; 1.77 ± 1.55 mSv) (p&lt;0.01). When adjusted for access site, CFs administered more radiation than either the ICFs or staff. However, differences between ICFs and staff were exclusively observed during transradial procedures (p&lt;0.01). With regards to contrast administration, ICFs administered less contrast (126.3 ± 57.6 mL) than either CFs (130±52.4 mL) or staff (132.7±47.6 mL) (p&lt;0.01)—again, a finding isolated to the transradial cohort. Of the 6,751 percutaneous coronary intervention cases, no significant differences existed between the ICFs or staff cardiologists in patient radiation exposure—but a CF as the primary operator resulted in an 18% increase in radiation exposure. Notably, contrast use was not different amongst the types of operators (p&lt;0.05). Conclusion: In conclusion, having a cardiology fellow as primary operator during invasive cardiac procedures increases patient radiation exposure and minimally increases contrast administration. Strategies to minimize patient radiation exposure while maintaining trainee involvement should be evaluated

Platelet reactivity following high loading doses of clopidogrel in patients undergoing primary percutaneous coronary angioplasty: A pilot study

Background: Rapid inhibition of platelet function is critical in patients referred for primary percutaneous coronary intervention (PCI) to prevent stent thrombosis. We sought to determine the antiplatelet effects of two clopidogrel high loading dose (LD) strategies on platelet reactivity in patients presenting with ST-elevation myocardial infarction (STEMI). Methods: Patients referred for primary PCI were randomly assigned to one of two clopidogrel LDs initiated before catheterization: 600 mg vs. 600/600 mg (second dose 3 h after first LD). Platelet function testing was performed at baseline, and at 1, 2, 4, 6, 24, and 48 h after the initial LD using the VerifyNow device. The primary endpoint was the proportion of patients with high platelet reactivity (HPR) at 24 h defined as a P2Y12 reaction unit (PRU) measurement >208. Results: Fifty-four patients were assigned to clopidogrel as a single 600 mg LD (n = 27) or as a 600/600 mg double LD (n = 27). The proportion of patients with HPR at 24 h was recorded in 44.0% assigned to the 600 mg LD and 24.0% of patients assigned to 600/600 mg LD, p = 0.23. The mean PRU at 24 h was 191 ± 102 in the 600 mg group and 152 ± 94 in the 600/600 mg group, p = 0.16. There was no difference at all time points in HPR, and in mean PRUs between the LD regimens. Conclusions: High platelet reactivity persisted at 24 h in a significant proportion of patients referred for primary PCI regardless of two clopidogrel high LD strategies. These results may have implications regarding the risk of early stent thrombosis in STEMI patients treated with clopidogrel