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Automatic introduction of OpenMP for sequential applications has attracted significant attention recently because of the proliferation of multicore processors and the simplicity of using OpenMP to express parallelism for shared-memory systems. However, most previous research has only focused on C and Fortran applications operating on primitive data types. Modern applications using high-level abstractions, such as C++ STL containers and complex user-defined class types, are largely ignored due to the lack of research compilers that are readily able to recognize high-level object-oriented abstractions and leverage their associated semantics. In this paper, we use a source-to-source compiler infrastructure, ROSE, to explore compiler techniques to recognize high-level abstractions and to exploit their semantics for automatic parallelization. Several representative parallelization candidate kernels are used to study semantic-aware parallelization strategies for high-level abstractions, combined with extended compiler analyses. Preliminary results have shown that semantics of abstractions can help extend the applicability of automatic parallelization to modern applications and expose more opportunities to take advantage of multicore processors.

This case series evaluated use of injectable platelet rich fibrin (termed i-PRF+) for the treatment of female pattern hair loss (FPHL). Eleven individuals underwent 3-monthly intradermal injections of i-PRF+ using a mesotherapy gun. The mean number of hair follicles containing hairs per unit area improved at 3- and 6-months follow-up (p <.001), and all participants had a negative hair pull test. Hair volume and thickness, and patient-reported outcome scores also improved at follow-up (p <.001). Adverse effects were minor and self-limited. A series of three i-PRF+ injection sessions were effective for the treatment of FPHL, as shown by improved hair analysis parameters and patient self-assessment scores. [ABSTRACT FROM AUTHOR]

Background: Cosmeceutical preparations containing growth factors (GFs) are widely used for facial rejuvenation. Objective: We performed a systematic review to assess the evidence regarding their safety and effectiveness for facial rejuvenation. Methods: Electronic databases (Cochrane Library, EMBASE, MEDLINE, and Scopus) were searched from 2000 to October 2022 for prospective trials and case series assessing topical GF preparations for facial rejuvenation in 10 or more participants. Results: Thirty‐three studies, including 9 randomized controlled trials (RCTs) and 24 uncontrolled case series, representing 1180 participants receiving 23 different topical preparations containing GFs met the inclusion criteria and were included. Of the 33 studies, nine used a placebo or active control. The GF preparations were applied twice daily in all except two studies, with a mean treatment duration of 3 months. Based on the investigator's assessment, preparations containing GFs induce a modest improvement in skin texture (median < 50%), fine lines/wrinkles (median < 35%), and overall facial appearance (median < 20%) versus baseline. Participant‐assessed improvement was generally higher than investigator‐assessed response. Three comparative RCTs showed no statistically significant differences between treatments. Studies were limited by heterogeneity with regard to the source and number of GFs used in the preparations, information about additional ingredients, and lack of standardization in the outcome measures. The preparations were associated with a low risk of adverse events. The persistence of the clinical improvements beyond 6 months is not known. Conclusions: Administration of topical preparations containing GFs appears to be effective for facial skin rejuvenation, as demonstrated by the investigator‐ and participant‐reported outcome measures. [ABSTRACT FROM AUTHOR]

Background: Cosmeceutical products are an important therapeutic option for facial rejuvenation. Of these, topical application of growth factors has been shown to increase dermal collagen synthesis, improve skin texture, and reduce fine lines and wrinkles. Limited data exist for the use of growth factors in combination with microneedling. Objective: This prospective, single‐center, uncontrolled study evaluated the efficacy of topical growth factor treatment in conjunction with transdermal delivery of growth factors via home‐based microneedling for facial skin rejuvenation. Patients/Methods: Eleven healthy female individuals aged 33–61 years, with mild‐moderate facial wrinkling were included in the study. Over 3 months, participants received twice‐daily application of a topical recombinant human growth factor preparation (SkinGenuity® Regenerative and Reparative Serums) along with twice‐weekly transdermal delivery of growth factors using a home‐based microneedling (0.2 mm) device. Objective skin analysis (VISIA®) and a subjective patient‐reported outcome (FACE‐Q®) assessment measuring satisfaction with appearance were performed at baseline and after 3 months. Results: Objective skin analysis showed a significant improvement in skin texture (17.6%, p < 0.001), wrinkles (17.3%, p < 0.001), red areas (12.4%, p =0.004), and brown spots (6.0%, p =0.03) at 3 months follow‐up. FACE‐Q scales showed a significant improvement from baseline, including satisfaction with skin, facial appearance, nasolabial folds, cheeks, and lower face/jawline (all p ≤ 0.02). Numerical improvement in adverse effects related to skin was also observed (p = 0.07). No serious adverse effects were reported. Conclusions: Three months of twice‐daily topical growth factor treatment in conjunction with transdermal delivery of growth factors via microneedling improved skin analysis parameters and participant‐reported outcome measures, indicative of facial skin rejuvenation. [ABSTRACT FROM AUTHOR]

Background: Various injectable autologous platelet aggregate preparations have been developed and used for facial rejuvenation. Limited evidence exists for the use of these for augmentation of the lip. Objectives: This prospective, uncontrolled, single‐center study evaluated the qualitative and quantitative effects of an injectable platelet‐rich fibrin preparation (known as i‐PRF+) for lip augmentation. Patients/methods: PRF® PROCESS system technology was used to prepare i‐PRF+ supernatant. Ten healthy females were included in the study and received a single intradermal injection of i‐PRF+ in the upper and lower lips (5 ml in each quadrant, total ~2 ml). Participants were followed for 3 months post‐procedure. The efficacy of the procedure was assessed qualitatively by a subjective patient‐reported outcome (FACE‐Q) assessment and quantitatively by objective 3D skin surface volume analysis (ProFace®) at baseline and after 3 months. Results: FACE‐Q scales that measure satisfaction with skin and lip showed a statistically significant improvement from baseline (p = 0.04 and p = 0.02, respectively). Satisfaction with lip lines showed a numerical improvement with mean total scores for adverse effect scales related to the skin and lips reduced at 2 weeks post‐procedure (p = 0.03 and p = 0.13, respectively). Overall lip volume at 3‐month follow‐up was unchanged (p = 0.11). The treatment was well tolerated with only minor adverse effects. Conclusions: A single session of i‐PRF+ injections resulted in significant lip rejuvenation at 3‐month follow‐up, shown by improved patient‐reported outcome measure. No significant change in lip volume was observed. [ABSTRACT FROM AUTHOR]

Background: Autologous platelet‐derived preparations have been used in many surgical fields to improve healing outcomes, with benefits reported in several aesthetic indications. Aims: This single‐center, prospective, uncontrolled study evaluated the efficacy of injectable platelet‐rich fibrin (i‐PRF) for facial skin rejuvenation using an objective skin analysis system and validated patient‐reported outcome measures. Patients/Methods: PRF® PROCESS system technology was used to prepare i‐PRP. Eleven healthy female individuals were included in the study and over 3‐months received monthly intradermal injections of i‐PRF in 3 facial regions: malar areas (1 mL each side), nasolabial fold (0.5 mL each side), and upper lip skin above the vermilion border (1 mL). The efficacy of the procedures was assessed by objective skin analysis (VISIA®) and a subjective patient‐reported outcome (FACE‐Q) assessment at baseline and after 3 months. Results: A significant improvement in skin surface spots (P =.01) and pores (P =.03) was seen at 3‐months follow‐up. Other variables, such as skin texture, wrinkles, ultraviolet spots, and porphyrins, showed a numerical improvement. FACE‐Q scales that measure satisfaction with appearance all showed a significant improvement from baseline, including satisfaction with skin (P =.002), satisfaction with facial appearance (P =.025), satisfaction with cheeks (P =.001), satisfaction with lower face and jawline (P =.002), and satisfaction with lips (P =.04). No major adverse effects were reported. Conclusions: A series of three i‐PRF injections resulted in significant rejuvenation of the face skin at 3‐month follow‐up, as shown by improved skin analysis parameters and patient self‐assessment scores. [ABSTRACT FROM AUTHOR]

The aim of this study was to prospectively evaluate the diagnostic performance of strain elastography for the assessment of liver fibrosis in patients with chronic liver disease using Ishak (0–6) histology stage as a reference standard. Ninety-eight consecutive patients with suspected chronic liver disease scheduled for liver biopsy (n = 78) or histologically confirmed cirrhosis (n = 20) were enrolled. Liver fibrosis Index (LF Index) calculated by strain elastography, liver stiffness by transient elastography and serum fibrosis markers (aspartate aminotransferase-to-platelet ratio index and King's Score) were measured. Spearman's correlation coefficient between the LF Index, liver stiffness, serum fibrosis markers and fibrosis stage were calculated and compared using areas under the receiver-operating characteristics (AUROCs) curves. Among 73 patients who underwent strain elastography, there was weak correlation between fibrosis stage and the LF Index (Spearman's: ρ = 0.385 for Ishak score; P = 0.001). Among 52 patients who underwent strain elastography and transient elastography, the AUROC values using LF Index, transient elastography, aspartate aminotransferase-to-platelet ratio index and King's Score for diagnosing significant fibrosis (Ishak score ≥ 3) were 0.79, 0.87, 0.86 and 0.85, respectively (P < 0.0001) and for diagnosing severe fibrosis/cirrhosis (Ishak score ≥ 5) were 0.83, 0.94, 0.92 and 0.92, respectively (P < 0.0001). When comparing the diagnostic performance using LF Index, transient elastography, aspartate aminotransferase-to-platelet ratio index and King's Score, transient elastography shows a significantly higher AUROC value than LF Index in detecting severe fibrosis (P = 0.0149). The diagnostic performance of LF Index calculated by strain elastography was not statistically significantly different to the other noninvasive tests for the assessment of significant liver fibrosis but inferior to transient elastography for the assessment of severe fibrosis/cirrhosis. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is an aggressive hematological malignancy that is one of the more common pediatric malignancies in addition to occurring with high incidence in the aging population. Unfortunately, these patient groups are quite sensitive to toxicity from chemotherapy. Northern Labrador tea, or Rhododendron tomentosum Harmaja (a.k.a. Ledum palustre subsp. decumbens) or "tundra tea," is a noteworthy medicinal plant used by indigenous peoples in Alaska, Canada, and Greenland to treat a diversity of ailments. However, laboratory investigations of Northern Labrador tea, and other Labrador tea family members, as botanical sources for anticancer compounds have been limited. Utilizing an AML cell line in both in vitro and in vivo studies, as well as in vitro studies using primary human AML patient samples, this study demonstrated for the first time that Northern Labrador tea extracts can exert anti-AML activity and that this may be attributed to ursolic acid as a constituent component. Therefore, this medicinal herb holds the potential to serve as a source for further drug discovery efforts to isolate novel anti-AML compounds. [ABSTRACT FROM AUTHOR]

Objectives Two-dimensional shear wave elastography (2D-SWE) imaging for the noninvasive assessment of tissue stiffness was assessed for reproducibility in healthy volunteers in quantifying liver elasticity, compared with an established point shear wave elastography (p-SWE) technique also known as virtual touch quantification (VTQ) (SIEMENS). Methods Eleven healthy volunteers were examined by four experienced operators on two occasions, separated by two weeks (sessions A and B). Ten 2D-SWE using LOGIQ E9 and p-SWE measurements using VTQ (in meters per second) were consecutively taken from deep portions of liver segments 5 or 6 away from vascular structures, using standard techniques. Inter- and intra-observer agreement was assessed by intraclass coefficient (ICC). Results A total of 880 2D-SWE and p-SWE velocities were recorded. Mean values from the four operators ranged between 1.188 and 1.196 m/s for 2D-SWE and 1.170 to 1.207 m/s for p-SWE. Interobserver reproducibility was good for both sessions with ICCs of 0.88 and 0.93 (2D-SWE) and 0.87 and 0.93 (p-SWE). The overall intra-operator reproducibility between sessions A and B was good for both p-SWE and 2D-SWE with ICC of 0.87 and 0.83, respectively. For inter- and intra-observer variability, the ICC was more than or equal to 0.71, indicating that the results were reliable. There was a strong and significant correlation between the 2D-SWE and p-SWE measurements ( r = 0.87, P = .0006), but their velocities did not agree equally across different velocities. Conclusions Two-dimensional SWE using LOGIQ E9 is a reliable and reproducible method for measuring elasticity in healthy volunteers and has a similar degree of reliability as p-SWE using VTQ, but absolute measurements from the two techniques should not be used interchangeably. [ABSTRACT FROM AUTHOR]

The article examines the effectiveness of Idarucizumab, acts as an antidote for reversal of dabigatran. Information about the summary in the mechanism of action and pharmacological properties of the antidote, is provided. An overview on the development, formulation and mechanism of Idarucizumab, is also highlighted.

The article reports on several aspects regarding therapeutic administration of an oral anticoagulant Dabigatran. It informs that dose of Dabigatran is country specific and is influenced by several factors including age of patient, estimated creatinine clearance and bleeding risk. It further informs that effects of Dabigatran administration does not need to be monitored regularly and its use can be continued in patients undergoing procedures associated with low risk of bleeding.

In this paper, we take a concrete step towards materializing our long-term goal of providing a fully automatic end-to-end tuning infrastructure for arbitrary program components and full applications. We describe a general-purpose offline auto-tuning framework and apply it to an application benchmark, SMG2000, a semi-coarsening multigrid on structured grids. We show that the proposed system first extracts computationally intensive loop nests into separate executable functions, a code transformation called outlining. The outlined loop nests are then tuned by the framework and subsequently integrated back into the application. Each loop nest is optimized through a series of composable code transformations, with the transformations parameterized by unbound optimization parameters that are bound during the tuning process. The values for these parameters are selected using a search-based auto-tuner, which performs a parallel heuristic search for the best-performing optimized variants of the outlined loop nests. We show that our system pinpoints a code variant that performs 2.37 times faster than the original loop nest. When the full application is run using the code variant found by the system, the application’s performance improves by 27%. [ABSTRACT FROM AUTHOR]

The last decade has seen the evaluation of several new oral anticoagulants that directly target thrombin or activated factor X (FXa). All demonstrate a rapid onset of action, a low potential for food and drug interactions, and a predictable anticoagulant effect that obviates the need for routine coagulation monitoring. Those agents at the most advanced stages of clinical development are a direct thrombin inhibitor, dabigatran, and direct FXa inhibitors, rivaroxaban and apixaban. Dabigatran and rivaroxaban are approved in more than 70 countries for prevention of venous thromboembolism in patients undergoing elective hip or knee arthroplasty, and apixaban is being considered for approval by regulatory agencies for this indication. Dabigatran was shown in a large phase III trial to be more effective and safer than warfarin for the prevention of stroke or systemic embolism in patients with atrial fibrillation and has recently been approved for this indication. Edoxaban, an oral FXa inhibitor, is also being evaluated in phase III clinical trials. This review summarizes the pharmacology, clinical trial results, and future role of the new oral anticoagulants in clinical practice. [ABSTRACT FROM AUTHOR]

The article presents a study on the potentiality of factor V Leiden (FVL) and prothrombin to cause venous thromboembolism (VTE). The study was assessed according to three variables, the patient, design and follow-ups. The study revealed that both FVL and prothrombin are identified to be high predisposing factor to VTE.

Sophisticated parallel languages are difficult to develop; most parallel distributed memory scientific applications are developed using a serial language, expressing parallelism through third party libraries (e.g. MPI). As a result, frameworks and libraries are often used to encapsulate significant complexities. We define a novel approach to optimize the use of libraries within applications. The resulting tool, named ROSE, leverages the additional semantics provided by library-defined abstractions enabling library specific optimization of application codes. It is a common perception that performance is inversely proportional to the level of abstraction. Our work shows that this is not the case if the additional semantics can be leveraged. We show how ROSE can be used to leverage the semantics within the compile-time optimization. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Accurate numerical modeling of complex physical, chemical, and biological systems requires numerical simulation capability over a large range of length scales, with the ability to capture rapidly varying phenomena localized in space and/or time. Adaptive mesh refinement (AMR) is a numerical process for dynamically introducing local fine resolution on computational grids during the solution process, in response to unresolved error in a computation. Fast adaptive composite-grid (FAC) methods are a class of algorithms that exploit the multilevel structure of AMR grids to solve elliptic problems efficiently. This paper develops a theoretical foundation for AFACx, an asynchronous FAC method. A new multilevel condition number estimate establishes that the convergence rate of the AFACx algorithm does not degrade as the number of refinement levels in the AMR hierarchy increases. [ABSTRACT FROM AUTHOR]

This paper presents numerical results for the asynchronous version of the fast adaptive composite-grid algorithm (AFACx). These results confirm the level-independent convergence bounds established theoretically in a companion paper. These numerical results include the case of AFACx applied to first-order system least-squares finite element discretizations of the stationary Stokes equations on curvilinear adaptive mesh refinement grids. [ABSTRACT FROM AUTHOR]

The authors discuss research on the efficacy of prothrombin complex concentrate (PCC) for urgent vitamin K antagonist (VKA) reversal. They reference the study "Efficacy and Safety of a 4-Factor Prothrombin Complex Concentrate in Patients on Vitamin K Antagonists Presenting With Major Bleeding: A Randomized, Plasma-Controlled, Phase IIIb Study" by Ravi Sarode published in the current issue of the journal. They believe that the work provides a framework for future evaluation of reversal agents.

Purpose To identify the minimum number of measurements required for the noninvasive assessment of liver fibrosis by using point shear-wave elastography (pSWE) and determine whether the use of a reliability indicator such as interquartile range [IQR]-to-median ratio will affect diagnostic performance. Materials and Methods Ten liver shear-wave velocity (SWV) measurements by pSWE were obtained in 232 participants. Interclass correlation coefficients (ICC) between the median of the first two through the first nine measurements and all 10 measurements were calculated; the minimum number of measurements with ICC greater than 0.95 versus all 10 measurements was determined. The diagnostic performance of the minimum number of measurements and 10 measurements in identifying significant (Ishak stage, ≥3) and severe fibrosis or cirrhosis (Ishak stage, ≥5) was compared by using areas under the receiver operating characteristic curve. These were compared between measurements that demonstrated higher or lower reliability (IQR-to-median ratio of ≤ 30% and IQR-to-median ratio of > 30%, respectively). Results Compared with 10 measurements, a minimum of six SWV measurements was required. The overall area under the curve for diagnosing significant (areas under the receiver operating characteristic curve, 0.828 vs 0.839; P = .487) and severe fibrosis or cirrhosis (0.953 vs 0.969, respectively; P = .145) did not differ according to number of measurements (six vs 10); a median of six measurements resulted in only limited disagreement (nine of 232 [3.9%]) versus histologic evaluation. When using 10 measurements, higher reliability measurements showed a lower percentage of discordance between pSWE and significant fibrosis and severe fibrosis or cirrhosis (22 [14.7%] and three [2.0%] of 150 cases, respectively) compared with lower reliability measurements (26 [31.7%] and eight [9.8%] of 82 cases, respectively). Significant fibrosis was an independent predictor for lower reliability (hazard ratio, 2.22; P < .020). Conclusion A limited number of SWV measurements (median six vs median 10) were required for the assessment of liver fibrosis by using pSWE. The number of measurements had less influence on the diagnostic accuracy compared with lower reliability measurements. © RSNA, 2018 Online supplemental material is available for this article.

Background: Dabigatran and rivaroxaban are novel oral anticoagulants approved for prevention of venous thromboembolism after hip or knee arthroplasty. However, information assessing clinically important efficacy and bleeding outcomes of these 2 new agents versus low-molecular-weight heparin (enoxaparin) is lacking., Methods and Results: We separately pooled efficacy and safety data from 6 phase III randomized trials (18 405 participants) comparing equivalent durations of treatment with enoxaparin (40 mg once daily [od] or 30 mg twice daily) versus dabigatran (220 mg od) or versus rivaroxaban (10 mg od) after hip or knee arthroplasty. Odds ratios (OR) for individual outcomes were calculated for each trial and were pooled using the Mantel-Haenszel method. Compared with dabigatran, enoxaparin had a similar risk of symptomatic venous thromboembolism plus all-cause mortality (0.9% versus 1.1%; OR, 0.76; 95% confidence interval [CI], 0.44 to 1.31; I²=76%) and bleeding (5.0% versus 5.6%; OR, 0.90; 95% CI, 0.71 to 1.15; I²=0%). Compared with rivaroxaban, enoxaparin had a 2-fold higher risk of symptomatic venous thromboembolism plus all-cause mortality (1.2% versus 0.6%; OR, 2.04; 95% CI, 1.32 to 3.17; P<0.001; number needed to treat, 167; I²=0%) but demonstrated a significant lower risk of bleeding (2.5% versus 3.1%; OR, 0.79; 95% CI, 0.62 to 0.99; P=0.049; number needed to harm, 167; I²=0%)., Conclusions: In patients undergoing hip or knee arthroplasty, enoxaparin and dabigatran showed similar rates of efficacy and bleeding. Enoxaparin was less effective than rivaroxaban but had a lower risk of bleeding. These results may have important implications for the choice of prophylactic agent in major joint arthroplasty.

Background: Bleeding is a strong predictor of death in patients hospitalized for arterial thrombosis who are treated with antithrombotic therapy, but the prognostic importance of bleeding in patients receiving antithrombotic prophylaxis for venous thromboembolism is uncertain., Methods and Results: Using Cox proportional hazards modeling, we examined the association between major bleeding and death at 30 days using pooled individual patient data from 8 large randomized controlled trials (n=13 085) comparing fondaparinux with control (low-molecular-weight heparin or placebo) for the prophylaxis of venous thromboembolism in hospitalized surgical or medical patients. Patients who developed major bleeding were older, were more likely to be male, had a lower body weight and lower creatinine clearance, and were more likely to be receiving fondaparinux. At 30 days, the risk of death was 7-fold higher among patients with a major bleeding event (8.6% versus 1.7%; adjusted hazard ratio, 6.96; 95% confidence interval, 4.60 to 10.51). There was a consistent pattern of reduced mortality in patients treated with fondaparinux irrespective of whether patients experienced major bleeding (6.8% versus 11.4%; hazard ratio, 0.58; 95% confidence interval, 0.27 to 1.23) or no major bleeding (1.5% versus 1.9%; hazard ratio, 0.77; 95% confidence interval, 0.59 to 1.02; P for heterogeneity=0.47)., Conclusions: Major bleeding in hospitalized surgical and medical patients participating in venous thromboembolism prevention trials is a strong predictor of mortality.

Background and Objectives: Venous thromboembolism (VTE) is a complex disorder influenced by numerous risk factors, and occurs frequently in at-risk hospitalized patients. Because appropriate prevention with thromboprophylaxis is underused, we wanted to create an electronic tool to provide a simple risk assessment and suggest appropriate prophylaxis., Design and Methods: To develop the risk matrix, iterative rating of odds ratios was performed for 60 predisposing VTE risk factors, using analytical methods that account for multiple risk factors in a single patient and their non-independence. For exposing risk factors, a single score was assigned to each set of factors, both medical (25 items) and surgical conditions (144 items). A CART regression model was used to integrate the risk scales into a 4-level measure of overall risk. The validity of the level of risk and the appropriateness of 11 different prophylactic approaches was assessed using the RAND/UCLA appropriateness method and validated by expert opinion ratings (n=1998) on sample case scenarios (n=108)., Results: Correlation between the level of risk calculated by the risk matrix and that offered by expert opinion for individual surgical and medical clinical cases was high (65% and 70%, respectively). The matrix over-estimated the level of risk, compared with that offered by expert opinion, in 28% and 20% of surgical and medical cases, respectively, but the appropriate prophylaxis suggested was no different. Between-expert agreement on the appropriateness of the prophylaxis recommendations was high (90-94% of indications)., Interpretation and Conclusions: This computer-based electronic tool for individualized assessment of venous thromboembolic risk successfully identified both the perceived risk of thrombosis and the appropriate prophylactic approach for medical and surgical patients.

Background: There is uncertainty about the role of intravenous unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) in patients with ST-elevation myocardial infarction (STEMI) treated with aspirin and thrombolysis., Methods and Results: We performed a meta-analysis of the randomized trials to assess the effect of UFH and LMWH on reinfarction, death, stroke, and bleeding. Fourteen trials involving a total of 25,280 patients were included (1239 comparing intravenous UFH versus placebo or no heparin; 16,943 comparing LMWH versus placebo; and 7098 comparing LMWH versus intravenous UFH). Intravenous UFH during hospitalization did not reduce reinfarction (3.5% versus 3.3%; odds ratio [OR], 1.08; 95% CI, 0.58 to 1.99) or death (4.8% versus 4.6%; OR, 1.04; 95% CI, 0.62 to 1.78) and did not increase major bleeding (4.2% versus 3.4%; OR, 1.21; 95% CI, 0.67 to 2.18) but increased minor bleeding (19.6% versus 12.5%; OR, 1.72; 95% CI, 1.22 to 2.43). During hospitalization/at 7 days, LMWH compared with placebo reduced the risk of reinfarction by approximately one quarter (1.6% versus 2.2%; OR, 0.72; 95% CI, 0.58 to 0.90; number needed to treat [NNT]=167) and death by &10% (7.8% versus 8.7%; OR, 0.90; 95% CI, 0.80 to 0.99; NNT=111) but increased major bleeding (1.1% versus 0.4%; OR, 2.70; 95% CI, 1.83 to 3.99; number needed to harm [NNH]=143) and intracranial bleeding (0.3% versus 0.1%; OR, 2.18; 95% CI, 1.07 to 4.52; NNH=500). The reduction in death with LMWH remained evident at 30 days. LMWH compared with UFH during hospitalization/at 7 days reduced reinfarction by &45% (3.0% versus 5.2%; OR, 0.57; 95% CI, 0.45 to 0.73; NNT=45), did not reduce death (4.8% versus 5.3%; OR, 0.92; 95% CI, 0.74 to 1.13) or increase major bleeding (3.3% versus 2.5%; OR, 1.30; 95% CI, 0.98 to 1.72), but increased minor bleeding (22.8% vs 19.4%; OR, 1.26; 95% CI, 1.12 to 1.43). The reduction in reinfarction remained evident at 30 days., Conclusions: In aspirin-treated patients with STEMI who are treated with thrombolysis, intravenous UFH has not been shown to prevent reinfarction or death. LMWH given for 4 to 8 days compared with placebo reduces reinfarction by approximately one quarter and death by &10% and when directly compared with UFH reduces reinfarction by almost one half. These data suggest that LMWH should be the preferred antithrombin in this setting.

Background: Randomized trials and meta-analyses have reached conflicting conclusions about the role of thrombolytic therapy for the treatment of acute pulmonary embolism., Methods and Results: We performed a meta-analysis of all randomized trials comparing thrombolytic therapy with heparin in patients with acute pulmonary embolism. Eleven trials, involving 748 patients, were included. Compared with heparin, thrombolytic therapy was associated with a nonsignificant reduction in recurrent pulmonary embolism or death (6.7% versus 9.6%; OR 0.67, 95% CI 0.40 to 1.12, P for heterogeneity=0.48), a nonsignificant increase in major bleeding (9.1% versus 6.1%; OR 1.42, 95% CI 0.81 to 2.46), and a significant increase in nonmajor bleeding (22.7% versus 10.0%; OR 2.63, 95% CI 1.53 to 4.54; number needed to harm=8). Thrombolytic therapy compared with heparin was associated with a significant reduction in recurrent pulmonary embolism or death in trials that also enrolled patients with major (hemodynamically unstable) pulmonary embolism (9.4% versus 19.0%; OR 0.45, 95% CI 0.22 to 0.92; number needed to treat=10) but not in trials that excluded these patients (5.3% versus 4.8%; OR 1.07, 95% CI 0.50 to 2.30), with significant heterogeneity between these 2 groups of trials (P=0.10)., Conclusions: Currently available data provide no evidence for a benefit of thrombolytic therapy compared with heparin for the initial treatment of unselected patients with acute pulmonary embolism. A benefit is suggested in those at highest risk of recurrence or death. The number of patients enrolled in randomized trials to date is modest, and further evaluation of the efficacy and safety of thrombolytic therapy for the treatment of high-risk patients with acute pulmonary embolism appears warranted.

Background and Objectives: Evidence-based international guidelines recommend that all patients undergoing elective hip or knee arthroplasty receive thromboprophylaxis with low-molecular-weight heparin or adjusted-dose warfarin. Our objective was to determine what proportion of patients undergoing elective hip or knee arthroplasty actually receive recommended thromboprophylaxis according to international guidelines., Design and Methods: We performed a prospective cohort study of 396 consecutive patients undergoing elective hip or knee arthroplasty between 1 May and 30 October, 2002. We collected baseline data, surgical and anesthetic details and recorded use of thromboprophylaxis and episodes of venous thromboembolism that occurred within 3 months of surgery., Results: The mean age of the patients was 69.4 years (SD 11.5 years), and 62.2% (95% CI: 57.3 to 66.9%) were female. Hip arthroplasty was performed in 39.4% (34.6 to 44.2%) and knee arthroplasty in 57.1% (52.2 to 61.9%). Recommended thromboprophylaxis with low-molecular-weight heparin or warfarin was administered to 51.5% (46.6 to 56.4%). Objectively diagnosed venous thromboembolism occurred in 5.3% (3.3 to 8.0%) of patients; 3.5% (1.9 to 5.9%) of events occurred during hospitalization and 1.8% (0.7 to 3.6%) occurred following discharge from hospital. There was no significant reduction in the incidence of venous thromboembolism among patients treated with recommended thromboprophylaxis compared with those who did not but this is not a randomized comparison and is potentially confounded by the indication for treatment., Interpretation and Conclusions: Current thromboprophylaxis practice at our institutions falls substantially short of national and international guidelines. The reasons for low thromboprophylaxis use should be further explored and strategies for change implemented in order to optimize clinical practice.

Background and Objectives: Venous thromboembolism is a frequent and serious disorder influenced by numerous factors. As the first step in creating a tool to assess an individual patient's risk of venous thromboembolism, we carried out a literature review in order to quantify risk factors for venous thromboembolism., Evidence and Information Sources: Risk factors were identified as being either predisposing, that is, those risks presented by a patient prior to hospital admission, or exposing, that is, those risks occurring when a patient is hospitalized for a certain medical condition or surgical procedure. Predisposing risk factors were classified with regard to the patients' characteristics (including general characteristics and inherent risk factors), and recent and chronic clinical conditions., Results: The major predisposing factors among the patients' characteristics were age, hormonal therapy and personal history of venous thromboembolism, along with inherited coagulation factor abnormalities. Clinical situations associated with the highest risk of venous thromboembolism were recent surgery, hospitalization for medical conditions and immobilization, moderate to severe congestive heart failure, and malignancy., Conclusions: This literature review will assist in the development of a suitable risk assessment tool for aiding healthcare professionals to decide whether to employ thromboprophylaxis, and, if so, to select the appropriate type and duration of prophylaxis.

Purpose: To retrospectively review bilateral venograms free of thrombus to evaluate the frequency and types of variations seen in venous anatomy., Materials and Methods: A retrospective review of 404 bilateral (808 limbs) lower limb venograms obtained from medical patients participating in a thromboprophylaxis clinical trial and found to be free of thrombus was performed. Venograms were evaluated according to predetermined criteria for the presence of duplication of vessels and inter- and intraindividual variations in venous anatomy. Variations were assessed with analysis of variance and chi2 tests., Results: Two vessels were seen in the popliteal fossa on 337 (42%) of 808 venograms, and 41 (5%) were true duplicated popliteal veins. There were 253 (31%) duplicated superficial femoral veins (SFVs), with 12 (1.5%) being complex duplicated systems. Of 265 duplicated SFVs, 138 (52%) began in the midthigh region and 80 (30%), in the adductor canal region. The duplicated vessel was medial to the main SFV in 122 (46%), lateral in 131 (49%), and both (ie, triplications) in 12 (4.5%). The length of the duplicated SFV ranged from 1 to 35 cm; 6-15 cm was the most common length in 162 (62%) SFVs. There was no significant association between the incidence of anatomic variations and age or sex (P >.1). The presence of multiple vessels in one leg was strongly correlated with the probability of occurrence in the other leg (P <.001)., Conclusion: Variations in lower limb venous anatomy are common and have important implications for the US diagnosis of deep vein thrombosis., (Copyright RSNA, 2003.)