Faculty Bibliography

BACKGROUND:Bleeding is a major limitation of antithrombotic therapy among invasively managed non-ST-segment elevation acute coronary syndromes (NSTE-ACS) patients; therefore, we examined the use of radial access and its association with outcomes among NSTE-ACS patients. METHODS:Clinical characteristics and geographic variation in radial access were examined, as well as its association with bleeding, red blood cell transfusion and ischemic outcomes (96-hour death/myocardial infarction/recurrent ischemic/thrombotic bailout; 30-day death/myocardial infarction; 1-year death) in the EARLY versus delayed, provisional eptifibatide in acute coronary syndromes trial. RESULTS:Of 9126 patients, 13.5% underwent radial-access catheterization. Female sex, age, weight, and prior revascularization were inversely associated with radial access, and its use varied widely by country (2%-97%). There were fewer GUSTO severe/moderate bleeds and red blood cell transfusions in the radial access group; however, it was attenuated after adjustment (odds ratio 0.73, 95% confidence intervals [CI] [0.50-1.06], P = .094 and 1.00 [0.71-1.40] P = .991). Ischemic outcomes did not differ by access site. CONCLUSIONS:In this post hoc analysis of a large clinical trial, there was significant international variation in use of radial access for NSTE-ACS patients undergoing invasive management, and it was preferentially used in those at lower risk for bleeding. Radial approach was not associated with a significant reduction in either bleeding or ischemic outcomes. Further study is needed to determine whether wider application of radial approach to acute coronary syndrome patients at high risk for bleeding improves overall outcomes.

With the large number of antithrombotic therapies available and under investigation for the treatment of non-ST-segment elevation acute coronary syndromes (NSTE ACS), practice guidelines now stress the importance of selecting an antithrombotic strategy according to the efficacy and safety profiles of the chosen agent. Contemporary trials have incorporated bleeding along with ischemic end points into a composite end point commonly referred to as net clinical benefit, which allows for simultaneous evaluation of the differences between benefit and harm for an investigational antithrombotic therapy. However, incorporating major bleeding into a composite end point that includes ischemic events is not warranted and is associated with many pitfalls. In this article, we discuss the validity of combining efficacy and safety end points to form a net clinical benefit composite end point with the traditional time-to-event analysis for trials evaluating antithrombotic therapies for NSTE ACS. We describe alternative statistical approaches for concurrent assessment of the safety and efficacy of antithrombotic therapies used to treat patients with NSTE ACS.

BACKGROUND:Prior trials suggest it is safe to defer transfusion at hemoglobin levels above 7 to 8 g/dL in most patients. Patients with acute coronary syndrome may benefit from higher hemoglobin levels. METHODS:We performed a pilot trial in 110 patients with acute coronary syndrome or stable angina undergoing cardiac catheterization and a hemoglobin <10 g/dL. Patients in the liberal transfusion strategy received one or more units of blood to raise the hemoglobin level ≥10 g/dL. Patients in the restrictive transfusion strategy were permitted to receive blood for symptoms from anemia or for a hemoglobin <8 g/dL. The predefined primary outcome was the composite of death, myocardial infarction, or unscheduled revascularization 30 days post randomization. RESULTS:Baseline characteristics were similar between groups except age (liberal, 67.3; restrictive, 74.3). The mean number of units transfused was 1.6 in the liberal group and 0.6 in the restrictive group. The primary outcome occurred in 6 patients (10.9%) in the liberal group and 14 (25.5%) in the restrictive group (risk difference = 15.0%; 95% confidence interval of difference 0.7% to 29.3%; P = .054 and adjusted for age P = .076). Death at 30 days was less frequent in liberal group (n = 1, 1.8%) compared to restrictive group (n = 7, 13.0%; P = .032). CONCLUSIONS:The liberal transfusion strategy was associated with a trend for fewer major cardiac events and deaths than a more restrictive strategy. These results support the feasibility of and the need for a definitive trial.

BACKGROUND:Radial access for percutaneous coronary intervention (r-PCI) is associated with reduced vascular complications; however, previous reports have shown that <2% of percutaneous coronary intervention (PCI) procedures in the United States are performed via the radial approach. Our aims were to evaluate temporal trends in r-PCI and compare procedural outcomes between r-PCI and transfemoral PCI. METHODS AND RESULTS/RESULTS:We conducted a retrospective cohort study from the CathPCI registry (n=2 820 874 procedures from 1381 sites) between January 2007 and September 2012. Multivariable logistic regression models were used to evaluate the adjusted association between r-PCI and bleeding, vascular complications, and procedural success, using transfemoral PCI as the reference. Outcomes in high-risk subgroups such as age ≥75 years, women, and patients with acute coronary syndrome were also examined. The proportion of r-PCI procedures increased from 1.2% in quarter 1 2007 to 16.1% in quarter 3 2012 and accounted for 6.3% of total procedures from 2007 to 2012 (n=178 643). After multivariable adjustment, r-PCI use in the studied cohort of patients was associated with lower risk of bleeding (adjusted odds ratio, 0.51; 95% confidence interval, 0.49-0.54) and lower risk of vascular complications (adjusted odds ratio, 0.39; 95% confidence interval, 0.31-0.50) in comparison with transfemoral PCI. The reduction in bleeding and vascular complications was consistent across important subgroups of age, sex, and clinical presentation. CONCLUSIONS:There has been increasing adoption of r-PCI in the United States. Transradial PCI now accounts for 1 of 6 PCIs performed in contemporary clinical practice. In comparison with traditional femoral access, transradial PCI is associated with lower vascular and bleeding complication rates.

OBJECTIVES/OBJECTIVE:This study sought to determine if there is an association between bleed location and clinical outcomes in acute coronary syndromes (ACS) patients. BACKGROUND:The prognostic significance of bleeding location among ACS patients undergoing cardiac catheterization is not well known. METHODS:We analyzed in-hospital bleeding events among 9,978 patients randomized in the SYNERGY (Superior Yield of the New Strategy of Enoxaparin, Revascularization, and Glycoprotein IIb/IIIa Inhibitors) study. Bleeding events were categorized by location as access site, systemic, surgical, or superficial, and severity was graded using the GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) definition. We assessed the association of each bleeding location and severity with 6-month risk of death or myocardial infarction using a multicovariate-adjusted Cox proportional hazard model. RESULTS:A total of 4,900 bleeding events were identified among 3,694 ACS patients with in-hospital bleeding. Among 4,679 GUSTO mild/moderate bleeding events, only surgical and systemic bleeds were associated with an increased risk of 6-month death or myocardial infarction (adjusted hazard ratio [HR]: 2.52 [95% confidence interval (CI): 2.16 to 2.94, and 1.40 [95% CI: 1.16 to 1.69], respectively). Mild/moderate superficial and access-site bleeds were not associated with downstream risk (adjusted HR: 1.17 [95% CI: 0.97 to 1.40], and 0.96 [95% CI: 0.82 to 1.12], respectively). Among 221 GUSTO severe bleeds, surgical bleeds were associated with the highest risk (HR: 5.27 [95% CI: 3.80 to 7.29]), followed by systemic (HR: 4.48 [95% CI: 2.98 to 6.72]), and finally access-site bleeds (HR: 3.57 [95% CI: 2.35 to 5.40]). CONCLUSIONS:Among ACS patients who develop in-hospital bleeding, systemic and surgical bleeding are associated with the highest risks of adverse outcomes regardless of bleeding severity. Although the most frequent among bleeds, GUSTO mild/moderate access-site bleeding is not associated with increased risk. These data underscore the importance of strategies to minimize overall bleeding risk beyond vascular access site management.

BACKGROUND:New percutaneous coronary intervention (PCI) device technologies are often rapidly adopted into clinical practice, yet few studies have examined the overall impact of these new technologies on patient outcomes in community practice. METHODS:In hopes of determining temporal trends in PCI outcomes, we used data from the Centers for Medicare & Medicaid Service's Chronic Condition Warehouse (n = 3,250,836) by comparing patient characteristics and rates of 3-year major adverse cardiac events (MACE) across the balloon angioplasty (POBA) era (01/1991-09/1995), the bare metal stent (BMS) era (02/1998-04/2003), and the drug-eluting stent (DES) era (05/2004-10/2006). The adjusted association between era and outcomes was determined with Cox proportional hazards modeling (POBA era as reference). RESULTS:Compared with the POBA era, patients undergoing PCI were significantly older and had more medical comorbidities, and the risk for 3-year MACE was significantly lower during the BMS and DES eras (BMS vs. POBA adjusted HR [95% CI]: 0.930 [0.926-0.935]; DES vs. BMS: 0.831 [0.827-0.835]). Compared with males, the adjusted risk for 3-year MACE among females was lower during the POBA era, but slightly higher during the BMS and DES eras. Across all three eras, patients ≥75 years of age had higher adjusted risk for MACE compared with younger patients, and the risk for revascularization was lower for both females and older patients. CONCLUSIONS:Despite its application in older and sicker Medicare beneficiaries, there has been a significant decrease in post-PCI MACE over time. The risk for death or myocardial infarction is higher among females and older patients compared with males and younger patients; therefore, future studies should focus on improving clinical outcomes in these high-risk subgroups.

OBJECTIVES/OBJECTIVE:The aim of this study was to describe usage of the wearable cardioverter-defibrillator (WCD) during mandated waiting periods following myocardial infarction (MI) for patients perceived to be at high risk for sudden cardiac arrest (SCA). BACKGROUND:Current device guidelines and insurance coverage require waiting periods of either 40 days or 3 months before implanting a cardioverter-defibrillator post-myocardial infarction (MI), depending on whether or not acute revascularization was undertaken. METHODS:We assessed characteristics of and outcomes for patients who had a WCD prescribed in the first 3 months post-MI. The WCD medical order registry was searched for patients who were coded as having had a "recent MI with ejection fraction ≤35%" or given an International Classification of Diseases, Ninth Revision 410.xx diagnostic code (acute MI), and then matched to device-recorded data. RESULTS:Between September 2005 and July 2011, 8,453 unique patients (age 62.7 ± 12.7 years, 73% male) matched study criteria. A total of 133 patients (1.6%) received 309 appropriate shocks. Of these patients, 91% were resuscitated from a ventricular arrhythmia. For shocked patients, the left ventricular ejection fraction (LVEF) was ≤30% in 106, 30% to 35% in 17, >36% in 8, and not reported in 2 patients. Of the 38% of patients not revascularized, 84% had a LVEF ≤30%; of the 62% of patients revascularized, 77% had a LVEF ≤30%. The median time from the index MI to WCD therapy was 16 days. Of the treated patients, 75% received treatment in the first month, and 96% within the first 3 months of use. Shock success resulting in survival was 84% in nonrevascularized and 95% in revascularized patients. CONCLUSIONS:During the 40-day and 3-month waiting periods in patients post-MI, the WCD successfully treated SCA in 1.4%, and the risk was highest in the first month of WCD use. The WCD may benefit individual patients selected for high risk of SCA early post-MI.

BACKGROUND:Bleeding is a common, noncardiac, preventable complication of percutaneous coronary intervention. We compared the relative safety of radial access and bivalirudin in percutaneous coronary intervention. METHODS AND RESULTS/RESULTS:From CathPCI Registry, we determined the association between the site of arterial access, bivalirudin, and periprocedural bleeding rates in 501 017 patients. Radial access patients receiving heparin (radial group) were compared with those receiving bivalirudin (radial combination group). Femoral access patients who had bivalirudin and a vascular closure device served as a reference group (femoral group). An inverse probability weighting analysis incorporating propensity scores was used to compare groups. The overall rate of bleeding was 2.59%. It was 2.71% in the femoral group, 2.5% in the radial group, and 1.82% in the radial combination groups (P<0.001). When compared with femoral group, the adjusted odds ratio for bleeding was significantly lower for patients with radial combination group (odds ratio, 0.79; 95% confidence interval, 0.72-0.86), but not for radial group (odds ratio, 0.96; 95% confidence interval, 0.88-1.05), unless patients treated with IIb/IIIa were excluded (radial group-IIb/IIIa odds ratio, 0.84; 95% confidence interval, 0.75-0.94).The number needed to treat to prevent 1 bleeding event with radial combination group was 138, whereas the number needed to treat to prevent 1 bleeding event in high-bleeding risk patients was 68. CONCLUSIONS:In this observational analysis, the combination of bivalirudin and radial access was associated with reduced bleeding event rate. This benefit was present across the entire spectrum of preprocedural risk of bleeding, with or without exposure to IIb/IIIa inhibitors. These data support an adequately powered randomized trial comparing bleeding avoidance strategies.