Vascular Complications of Transradial Access for Cardiac Catheterization

Transradial access has been increasingly adopted for cardiac catheterization. It is crucial for operators to recognize potential vascular complications associated with radial artery access. Prevention, early detection, and prompt treatment of vascular complications are essential to prevent serious morbidities. This review aims to raise awareness of transradial access vascular complications. Radial artery spasm is treated with intra-arterial verapamil and/or nitroglycerine. Hemorrhagic complications, such as perforation, hematoma, arteriovenous fistula, and pseudoaneurysm, are treated with prolonged compression. Patent hemostasis and adequate anticoagulation are used to prevent radial artery occlusion. Hand ischemia is a rare complication not associated with abnormal results of the Allen or Barbeau test, and can be treated with intra-arterial verapamil, IV heparin, and IV diltiazem. Finally, an attentive monitoring protocol for the timely detection of vascular complications should be implemented in daily practice

A study of steel alloys for potential use in CO2 sequestration

The effect of CO2 as a greenhouse gas, and the potential of global warming, has led to the study of sequestration of CO2 as a mineral carbonate. Some of the processes of mineral sequestration involve handing large tonnages of silicate minerals and reacting them with CO2. In this study the Albany Research Center evaluated the effects of wear and corrosion individually, and any possible synergetic effects resulting from a combination of wear and corrosion, on steel alloys that might be used in CO2 sequestration. By understanding the mechanism of slurry material loss, a better selection of erosion/corrosion resistant steel alloys can be chosen which in turn help plan construction costs. Four different conventional alloys were chosen. The alloys include AISI 1080 carbon steel, a 9Cr, 1 Mo steel, a 316 stainless steel, and a heat treatable 440C stainless steel. These materials covered a large range of alloy composition and cost. A variety of erosion and corrosion tests were used to evaluate the steels response to selected sequestration environments. The tests used included: (i) wear from dry Jet and HAET erosion tests, (ii) corrosion from immersion tests, and (iii) slurry erosion/corrosion tests. The slurry wear tests were conducted using a 270-μm silica abrasive in water and a solution (a mixture of sodium chloride, magnesium chloride, and sodium carbonate) saturated with CO2 at pH levels of 4.5 and 9.4. The results of these tests were compared with the results dry erosion and immersion corrosion tests. The results of the various tests were then used to evaluate the mechanism of material loss and determine is the presence of synergetic effects. The corrosion test showed little loss of material for all alloys. The erosion tests showed only a small difference between alloys. The slurry tests showed synergistic effect of combining erosion and corrosion resulted in a significant additional loss of material. It was further found both increasing the hardness and amounts of substitution chromium decreased the alloy loss rate

How Old is Too Old? Closure of Patent Foramen Ovale in Older Patients

Percutaneous closure of a patent foramen ovale (PFO) reduces the risk of recurrent cryptogenic stroke specifically in younger patients. The three randomized controlled trials that led to the widespread adoption of PFO closure excluded patients over the age of 60 years. Older patients frequently have other cardiac and vascular conditions that are common risk factors for stroke, whereas paradoxical embolism through a PFO is relatively rare. Younger patients theoretically benefit the most from closure due to longer lifetime exposure risk and absence of other traditional risk factors. PFO in older patients with cryptogenic strokes is often encountered in clinical practice, making up an increasing number of cardiology referrals, yet cardiologists lack guidelines and evaluation tools for these patients. This review explores the history of PFO closure – emphasizing data in older adults – and discusses the evaluation and treatment of older people with cryptogenic stroke and PFO while further trials in this important population are awaited

Increased Risk of Non-Q Wave Myocardial Infarction After Directional Atherectomy Is Platelet Dependent: Evidence From the EPIC Trial

AbstractObjectives. We sought to determine the effects of platelet glycoprotein IIb/IIIa receptor blockade on adverse outcomes, especially non-Q wave myocardial infarction, in patients undergoing directional atherectomy in the Evaluation of c7E3 for the Prevention of Ischemic Complications (EPIC) trial.Background. Randomized trials comparing directional atherectomy with percutaneous transluminal coronary angioplasty (PTCA) have demonstrated modest benefits favoring atherectomy but at a cost of increased acute ischemic complications, notably non-Q wave myocardial infarction. The mechanism for this excess risk is unknown.Methods. Of 2,038 high risk patients undergoing coronary intervention in the EPIC trial, directional atherectomy was performed in 197 (10%). Patients randomly received the chimeric glycoprotein IIb/IIIa antibody 7E3 (c7E3), as a bolus or a bolus and 12-h infusion or placebo. Study end points included death, myocardial infarction, repeat intervention or bypass surgery.Results. Patients undergoing directional atherectomy had a lower baseline risk for acute complications but had a higher incidence of any myocardial infarction (10.7% vs. 6.3%, p = 0.021) and non-Q wave myocardial infarction (9.6% vs. 4.9%, p = 0.006). Bolus and infusion of c7E3 reduced non-Q wave myocardial infarctions by 71% after atherectomy (15.4% for placebo vs. 4.5% for bolus and infusion, p = 0.046). Non-Q wave myocardial infarction rates after PTCA were not affected by c7E3, although Q wave myocardial infarctions were reduced from 2.6% to 0.8% (p = 0.017).Conclusions. The EPIC trial confirmed the increased risk of non-Q wave myocardial infarction with directional atherectomy use compared with PTCA. A bolus and 12-h infusion of the glycoprotein IIb/IIIa receptor inhibitor c7E3 abolished this excess risk. Directional atherectomy-related non-Q wave myocardial infarction appears to be platelet aggregation dependent

Clinical outcomes after detection of elevated cardiac enzymes in patients undergoing percutaneous intervention

AbstractObjectives. We examined the relations of elevated creatine kinase (CK) and its myocardial band isoenzyme (CK-MB) to clinical outcomes after percutaneous coronary intervention (PCI) in patients enrolled in Integrilin (eptifibatide) to Minimize Platelet Aggregation and Coronary Thrombosis-II (trial) (IMPACT-II), a trial of the platelet glycoprotein IIb/IIIa inhibitor eptifibatide.Background. Elevation of cardiac enzymes often occurs after PCI, but its clinical implications are uncertain.Methods. Patients undergoing elective, scheduled PCI for any indication were analyzed. Parallel analyses investigated CK (n = 3,535) and CK-MB (n = 2,341) levels after PCI (within 4 to 20 h). Clinical outcomes at 30 days and 6 months were stratified by postprocedure CK and CK-MB (multiple of the site’s upper normal limit).Results. Overall, 1,779 patients (76%) had no CK-MB elevation; CK-MB levels were elevated to 1 to 3 times the upper normal limit in 323 patients (13.8%), to 3 to 5 times normal in 84 (3.6%), to 5 to 10 times normal in 86 (3.7%), and to >10 times normal in 69 patients (2.9%). Elevated CK-MB was associated with an increased risk of death, reinfarction, or emergency revascularization at 30 days, and of death, reinfarction, or surgical revascularization at 6 months. Elevated total CK to above three times normal was less frequent, but its prognostic significance paralleled that seen for CK-MB. The degree of risk correlated with the rise in CK or CK-MB, even for patients with successful procedures not complicated by abrupt closure.Conclusions. Elevations in cardiac enzymes, including small increases (between one and three times normal) often not considered an infarction, are associated with an increased risk for short-term adverse clinical outcomes after successful or unsuccessful PCI

Small instream infrastructure: Comparative methods and evidence of environmental and ecological responses

1. Around the globe, instream infrastructures such as dams, weirs, and culverts associated with roads are wide‐spread and continue to be constructed. There is limited documentation of smaller infrastructure because of mixed regulation and laws related to instream construction, as well as difficulty in documentation because of their size and frequency in waterscapes. 2. We reviewed evidence of different methods used to quantify environmental and ecological responses (positive, negative, or neutral) to dams, weirs, and culverts. 3. Most studies (78% of 87) in our review evaluated dams or weirs, and more than half evaluated environmental or ecological responses at more than one of these structures. More than half of the studies used spatial (disturbed–undisturbed in the same or a different catchment) rather than temporal (before–after construction or before–after destruction) comparative methods. Evaluations also tended to focus on ecological variables, most specifically on fish community responses (just over a quarter) to infrastructure. 4. More than half (58%) of the evaluations at dams, weirs, or culverts reported negative environmental or ecological responses. Discrepancies in responses recorded for different infrastructure types could be partially explained by the focus on ecological responses in reviewed studies and related metrics used for evaluations (e.g. biotic groups, richness, and abundance), the imbalance of studies at different infrastructure types, and discrepancies in spatial and temporal scales of evaluations compared to those at which the variables respond to infrastructure. 5. Despite the abundance of road culverts greatly exceeding the number of small or large dams worldwide, they were evaluated in only 22% of studies that we reviewed. Our findings underscore the need for studies to not only better understand local but also cumulative impacts of these smaller infrastructure, as these could be greater than those caused by large infrastructure depending on their location, density, and type, among other factors. Such studies are needed to inform infrastructure planning and watershed management

Clinical Decision Making Staging of Multivessel Percutaneous Coronary Interventions: an Expert Consensus Statement from the Society for Cardiac Angiography and Interventions

and Gregory J. Dehmer, 7 MD, FSCAI Percutaneous coronary interventions (PCIs) to treat multivessel coronary artery disease (MVCAD) may involve single-vessel or multivessel interventions, performed in one or more stages. This consensus statement reviews factors that may influence choice of strategy and includes six recommendations to guide decisions regarding staging of PCI V C 2011 Wiley Periodicals, Inc

Surface and Temporal Biosignatures

Recent discoveries of potentially habitable exoplanets have ignited the prospect of spectroscopic investigations of exoplanet surfaces and atmospheres for signs of life. This chapter provides an overview of potential surface and temporal exoplanet biosignatures, reviewing Earth analogues and proposed applications based on observations and models. The vegetation red-edge (VRE) remains the most well-studied surface biosignature. Extensions of the VRE, spectral "edges" produced in part by photosynthetic or nonphotosynthetic pigments, may likewise present potential evidence of life. Polarization signatures have the capacity to discriminate between biotic and abiotic "edge" features in the face of false positives from band-gap generating material. Temporal biosignatures -- modulations in measurable quantities such as gas abundances (e.g., CO2), surface features, or emission of light (e.g., fluorescence, bioluminescence) that can be directly linked to the actions of a biosphere -- are in general less well studied than surface or gaseous biosignatures. However, remote observations of Earth's biosphere nonetheless provide proofs of concept for these techniques and are reviewed here. Surface and temporal biosignatures provide complementary information to gaseous biosignatures, and while likely more challenging to observe, would contribute information inaccessible from study of the time-averaged atmospheric composition alone.Comment: 26 pages, 9 figures, review to appear in Handbook of Exoplanets. Fixed figure conversion error