Faculty Bibliography

Percutaneous coronary intervention (PCI) induces thrombin generation and is associated with the risk of acute, subacute, or long-term ischaemic events. Therefore, intravenous anticoagulation is recommended to minimize thrombotic complications. The intensity and duration of anticoagulation needed are dependent on the clinical presentation (elective PCI for stable coronary artery disease, PCI for non-ST elevation acute coronary syndromes, or primary PCI for ST-segment elevation myocardial infarction) and procedural features. As both ischaemic and periprocedural bleeding complications are associated with acute and long-term mortality, the optimal level of anticoagulation and the best agents are a matter of debate. Despite a number of limitations and the lack of large randomized clinical trials, unfractionated heparin (UFH) is still been used in the majority of interventions. Intravenous enoxaparin, a low-molecular-weight heparin, leads to a more predictable level of anticoagulation and has been compared with UFH in patients with elective PCI and primary PCI with favourable results. The direct thrombin inhibitor bivalirudin has been studied in numerous trials and consistently shown to reduce bleeding complications when compared with UFH with or without glycoprotein IIb/IIIa inhibitors. This review will summarize the current status of anticoagulation for PCI and the results of most recent trials and give recommendations for different clinical scenarios.

OBJECTIVES/OBJECTIVE:Periprocedural bleedings, often related to vascular access site, represent an important drawback of percutaneous coronary procedures and are associated with worse outcomes. Radial access (RA) and, potentially, femoral access (FA) with vascular closure device (VCD) are useful strategies in order to mitigate periprocedural bleedings; nevertheless, their relative efficacy is largely undetermined. We aimed to perform a systematic review and meta-analysis of available studies comparing the efficacy of RA and FA with hemostasis by VCD (FA + VCD) on the reduction of access-site complications and/or periprocedural bleedings. METHODS:Published studies reporting outcomes on access-site complications and periprocedural bleedings were included in the analysis. Data were extracted by two independent reviewers; odds ratio (OR) and 95% confidence interval (CI) were calculated by random-effects model and were used as summary statistics. RESULTS:We included in the analysis 13 studies, of which 5 were randomized. Access-site complications were reported by 11 studies, amounting to 157,031 patients (77,713 in the RA group and 79,318 in the FA + VCD group), whereas periprocedural bleedings were reported by 12 studies, amounting to 600,196 patients (137,277 in the RA group and 462,919 in the FA + VCD group). RA was associated with a significant reduction in access-site complications (OR, 0.25; 95% CI ,0.21-0.31; P<.001) and periprocedural bleedings (OR, 0.40; 95% CI, 0.34-0.48; P<.001) as compared with FA + VCD; the results were consistent among randomized and observational studies. CONCLUSIONS:This meta-analysis shows that RA is superior to FA + VCD in the reduction of access-site complications and periprocedural bleedings.

Several recent randomized controlled trials (RCTs) demonstrated better outcomes with multivessel complete revascularization (CR) than with infarct-related artery-only revascularization (IRA-OR) in patients with ST-segment elevation myocardial infarction. It is unclear whether CR should be performed during the index procedure (IP) at the time of primary percutaneous coronary intervention (PCI) or as a staged procedure (SP). Therefore, we performed a pairwise meta-analysis using a random-effects model and network meta-analysis using mixed-treatment comparison models to compare the efficacies of 3 revascularization strategies (IRA-OR, CR-IP, and CR-SP). Scientific databases and websites were searched to find RCTs. Data from 9 RCTs involving 2,176 patients were included. In mixed-comparison models, CR-IP decreased the risk of major adverse cardiac events (MACEs; odds ratio [OR] 0.36, 95% CI 0.25 to 0.54), recurrent myocardial infarction (MI; OR 0.50, 95% CI 0.24 to 0.91), revascularization (OR 0.24, 95% CI 0.15 to 0.38), and cardiovascular (CV) mortality (OR 0.44, 95% CI 0.20 to 0.87). However, only the rates of MACEs, MI, and CV mortality were lower with CR-SP than with IRA-OR. Similarly, in direct-comparison meta-analysis, the risk of MI was 66% lower with CR-IP than with IRA-OR, but this advantage was not seen with CR-SP. There were no differences in all-cause mortality between the 3 revascularization strategies. In conclusion, this meta-analysis shows that in patients with ST-segment elevation myocardial infarction and multivessel coronary artery disease, CR either during primary PCI or as an SP results in lower occurrences of MACE, revascularization, and CV mortality than IRA-OR. CR performed during primary PCI also results in lower rates of recurrent MI and seems the most efficacious revascularization strategy of the 3.

Importance:More than 100 million units of blood are collected worldwide each year, yet the indication for red blood cell (RBC) transfusion and the optimal length of RBC storage prior to transfusion are uncertain. Objective:To provide recommendations for the target hemoglobin level for RBC transfusion among hospitalized adult patients who are hemodynamically stable and the length of time RBCs should be stored prior to transfusion. Evidence Review:Reference librarians conducted a literature search for randomized clinical trials (RCTs) evaluating hemoglobin thresholds for RBC transfusion (1950-May 2016) and RBC storage duration (1948-May 2016) without language restrictions. The results were summarized using the Grading of Recommendations Assessment, Development and Evaluation method. For RBC transfusion thresholds, 31 RCTs included 12 587 participants and compared restrictive thresholds (transfusion not indicated until the hemoglobin level is 7-8 g/dL) with liberal thresholds (transfusion not indicated until the hemoglobin level is 9-10 g/dL). The summary estimates across trials demonstrated that restrictive RBC transfusion thresholds were not associated with higher rates of adverse clinical outcomes, including 30-day mortality, myocardial infarction, cerebrovascular accident, rebleeding, pneumonia, or thromboembolism. For RBC storage duration, 13 RCTs included 5515 participants randomly allocated to receive fresher blood or standard-issue blood. These RCTs demonstrated that fresher blood did not improve clinical outcomes. Findings:It is good practice to consider the hemoglobin level, the overall clinical context, patient preferences, and alternative therapies when making transfusion decisions regarding an individual patient. Recommendation 1: a restrictive RBC transfusion threshold in which the transfusion is not indicated until the hemoglobin level is 7 g/dL is recommended for hospitalized adult patients who are hemodynamically stable, including critically ill patients, rather than when the hemoglobin level is 10 g/dL (strong recommendation, moderate quality evidence). A restrictive RBC transfusion threshold of 8 g/dL is recommended for patients undergoing orthopedic surgery, cardiac surgery, and those with preexisting cardiovascular disease (strong recommendation, moderate quality evidence). The restrictive transfusion threshold of 7 g/dL is likely comparable with 8 g/dL, but RCT evidence is not available for all patient categories. These recommendations do not apply to patients with acute coronary syndrome, severe thrombocytopenia (patients treated for hematological or oncological reasons who are at risk of bleeding), and chronic transfusion-dependent anemia (not recommended due to insufficient evidence). Recommendation 2: patients, including neonates, should receive RBC units selected at any point within their licensed dating period (standard issue) rather than limiting patients to transfusion of only fresh (storage length: <10 days) RBC units (strong recommendation, moderate quality evidence). Conclusions and Relevance:Research in RBC transfusion medicine has significantly advanced the science in recent years and provides high-quality evidence to inform guidelines. A restrictive transfusion threshold is safe in most clinical settings and the current blood banking practices of using standard-issue blood should be continued.

Arterial access and haemostasis are fundamental aspects of procedures performed in the cardiac catheterization laboratory. The first description of arterial access for cardiac catheterization was in 1948, when surgical cut-down was used to access the radial artery. Over the next 2 decades, the preferred arteriotomy method transitioned from the Sones approach of brachial artery cut-down to the Seldinger and Judkins technique of percutaneous femoral artery access. Compared with the femoral approach, percutaneous transradial access results in reduced access-site bleeding, faster time to ambulation, and greater patient comfort. Several large-scale, randomized trials have also reported a survival advantage in patients with acute coronary syndromes treated with radial compared with femoral access. However, inconsistencies exist between the completed trials, and the underlying mechanism of a reduction in mortality with radial access is uncertain. Femoral artery haemostasis can be achieved with either manual compression or vascular closure devices, with recent studies suggesting improved outcomes with the use of active closure systems. Radial artery haemostasis is achieved through the use of wristbands that mimic manual compression, and 'non-occlusive' haemostasis reduces the risk of radial artery occlusion. Newer arterial access routes and closure approaches for large-bore devices are being actively investigated. Expertise in both femoral and radial artery access and intervention is essential for contemporary interventional cardiologists.

Large randomized clinical trials in cardiovascular disease have proliferated over the past 3 decades, with results that have influenced every aspect of cardiology practice. Despite these advances, there remains a substantial need for more high-quality evidence to inform cardiovascular clinical practice, given the increasing prevalence of cardiovascular disease around the world. Traditional clinical trials are increasingly challenging due to rising costs, increasing complexity and length, and burdensome institutional and regulatory requirements. This review will examine the current landscape of cardiovascular clinical trials in the United States, highlight recently conducted registry-based clinical trials, and discuss the potential attributes of the recently launched pragmatic clinical trial by the Patient-Centered Outcomes Research Institute's National Patient-Centered Clinical Research Network, called the ADAPTABLE (Aspirin Dosing: A Patient-centric Trial Assessing the Benefits and Long-term Effectiveness) trial.

This article discusses the controversies surrounding the use of transradial versus transfemoral approaches in the management of patients with ST-segment elevation myocardial infarction, beginning with a review of the benefits of transradial percutaneous coronary intervention (PCI) in this population. The unanswered questions about the mechanism underlying the mortality benefit of transradial PCI are discussed, concluding with recommendations for safe and effective strategies for adoption of the transradial approach to optimize outcomes in these high-risk patients.