2007 update to the ACC/AHA guidelines for the management of patients with unstable angina and non-ST-segment elevation myocardial infarction: implications for emergency department practice

Self-Administration of Aspirin After Chest Pain for the Prevention of Premature Cardiovascular Mortality in the United States: A Population-Based Analysis

BACKGROUND

Aspirin, an effective, low-cost pharmaceutical, can significantly reduce mortality if used promptly after acute myocardial infarction (AMI). However, many AMI survivors do not receive aspirin within a few hours of symptom onset. Our aim was to quantify the mortality benefit of self-administering aspirin at chest pain onset, considering the increased risk of bleeding and costs associated with widespread use.

METHODS AND RESULTS

We developed a population simulation model to determine the impact of self-administering 325 mg aspirin within 4 hours of severe chest pain onset. We created a synthetic cohort of adults ≥ 40 years old experiencing severe chest pain using 2019 US population estimates, AMI incidence, and sensitivity/specificity of chest pain for AMI. The number of annual deaths delayed was estimated using evidence from a large, randomized trial. We also estimated the years of life saved (YOLS), costs, and cost per YOLS. Initiating aspirin within 4 hours of severe chest pain onset delayed 13 016 (95% CI, 11 643-14 574) deaths annually, after accounting for deaths due to bleeding (963; 926-1003). This translated to an estimated 166 309 YOLS (149391-185 505) at the cost of $643 235 (633 944-653 010) per year, leading to a cost-effectiveness ratio of $3.70 (3.32-4.12) per YOLS.

CONCLUSIONS

For <$4 per YOLS, self-administration of aspirin within 4 hours of severe chest pain onset has the potential to save 13 000 lives per year in the US population. Benefits of reducing deaths post-AMI outweighed the risk of bleeding deaths from aspirin 10 times over.

Establishment of a nomogram model for acute chest pain triage in the chest pain center

Background

Acute myocardial infarction (AMI) is the leading life-threatening disease in the emergency department (ED), so rapid chest pain triage is important. This study aimed to establish a clinical prediction model for the risk stratification of acute chest pain patients based on the Point-of-care (POC) cardiac troponin (cTn) level and other clinical variables.

Methods

We conducted a post-hoc analysis of the database from 6,019 consecutive patients (excluding prehospital-diagnosed non-cardiac chest pain patients) attending a local chest pain center (CPC) in China between October 2016 and January 2019. The plasma concentration of cardiac troponin I (cTnI) was measured using a POC cTnI (Cardio Triage, Alere) assay. All the eligible patients were randomly divided into training and validation cohorts by a 7:3 ratio. We performed multivariable logistic regression to select variables and build a nomogram based on the significant predictive factors. We evaluated the model's generalization ability of diagnostic accuracy in the validation cohort.

Results

We analyzed data from 5,397 patients that were included in this research. The median turnaround time (TAT) of POC cTnI was 16 min. The model was constructed with 6 variables: ECG ischemia, POC cTnI level, hypotension, chest pain symptom, Killip class, and sex. The area under the ROC curve (AUC) in the training and validation cohorts was 0.924 and 0.894, respectively. The diagnostic performance was superior to the GRACE score (AUC: 0.737).

Conclusion

A practical predictive model was created and could be used for rapid and effective triage of acute chest pain patients in the CPC.

The Impact of Sonothrombolysis on Left Ventricular Diastolic Function and Left Atrial Mechanics Preventing Left Atrial Remodeling in Patients With ST Elevation Acute Myocardial Infarction

BACKGROUND

The diagnostic ultrasound-guided high mechanical index impulses during an intravenous microbubble infusion (sonothrombolysis) improve myocardial perfusion in acute ST segment elevation myocardial infarction, but its effect on left ventricular diastolic dysfunction (DD), left atrial (LA) mechanics and remodeling is unknown. We assessed the effect of sonothrombolysis on DD grade and LA mechanics.

METHODS

One hundred patients (59 ± 10 years; 34% women) were randomized to receive either high mechanical index impulses plus percutaneous coronary intervention (PCI) (therapy group) or PCI only (control group) (n = 50 in each group). Diastolic dysfunction grade and LA mechanics were assessed immediately before and after PCI and at 48 to 72 hours, 1 month, and 6 months of follow-up. Diastolic dysfunction grades were classified as grades I, II, and III. The LA mechanics was obtained by two-dimensional speckle-tracking echocardiography-derived global longitudinal strain (GLS).

RESULTS

As follow-up time progressed, increased DD grade was observed more frequently in the control group than in the therapy group at 1 month and 6 months of follow-up (all P < .05). The LA-GLS values were incrementally higher in the therapy group when compared with the control group at 48 to 72 hours, 24.0% ± 7.3% in the therapy group versus 19.6% ± 7.2% in the control group, P = .005; at 1 month, 25.3% ± 6.3% in the therapy group versus 21.5% ± 8.3% in the control group, P = .020; and at 6 months, 26.2% ± 8.7% in the therapy group versus 21.6% ± 8.5% in the control group, P = .015. The therapy group was less likely to experience LA remodeling (odds ratio, 2.91 [1.10-7.73]; P = .03). LA-GLS was the sole predictor of LA remodeling (odds ratio, 0.79 [0.67-0.94]; P = .006).

CONCLUSION

Sonothrombolysis is associated with better DD grade and LA mechanics, reducing LA remodeling.

NFKB1 Gene Mutant Was Associated with Prognosis of Coronary Artery Disease and Exacerbated Endothelial Mitochondrial Fission and Dysfunction

Endothelial apoptosis is the core pathological change in atherosclerotic cardiovascular disease, including coronary artery disease (CAD). Determining the molecular mechanisms underlying endothelial apoptosis is important. Nuclear factor kappa B (NF-κB) is a crucial transcription factor for controlling apoptosis. Our previous study demonstrated that the -94 ATTG ins/del mutant in the promoter of NFKB1 gene (rs28362491) is a risk factor for CAD. In the present study, we found that NFKB1 rs28362491 polymorphism was positively associated with increased major adverse cardiac and cerebrovascular events (MACCEs) in CAD patients. After adjusting for confounding factors including age, smoking, hypertension, glucose, and low-density lipoprotein cholesterol, the mutant DD genotype was an independent predictor of MACCEs (OR = 2.578, 95%CI = 1.64–4.05, P = 0.003). The in vitro study showed that mutant human umbilical vein endothelial cells (DD-mutant HUVECs) were more susceptible to high-glucose/palmitate-induced apoptosis, which was accompanied by decreased p50 expression and increased expression of cleaved caspase-3, Cytochrome c, and phospho-p65 (P < 0.05). The mitochondrial membrane potential was significantly lower, while increasing levels of mtROS and more opening of the mPTP were observed in DD-mutant HUVECs (P < 0.05). Furthermore, the percentage of cells with fragmented or spherical mitochondria was significantly higher in DD-mutant HUVECs than in wild-type cells (genotype II HUVECs) (P < 0.05). In addition, after stimulation with high glucose/palmitate, the NFKB1 gene mutant significantly increased the expression of Drp1, which indicated that the NFKB1 gene mutant affected the expression of mitochondrial morphology-related proteins, leading to excessive mitochondrial fission. In conclusion, the mutant DD genotype of the NFKB1 gene was an independent predictor of worse long-term prognosis for CAD patients. DD-mutant HUVECs exhibited abnormal activation of the NF-κB pathway and increased Drp1 expression, which caused excessive mitochondrial fission and dysfunction, ultimately leading to increased apoptosis.

Efficacy and Safety of Short-Term Dual Antiplatelet Therapy in East Asians: A Systematic Review and a Meta-Analysis of Randomized Clinical Trials

ABSTRACT

The optimal duration of dual antiplatelet therapy (DAPT) for patients implanted with new-generation drug-eluting stents in East Asians is currently still controversial. The purpose of this meta-analysis was to investigate the efficacy and safety of short-term DAPT in patients with those. In this study, randomized controlled trials from PubMed, EMBASE, and Cochrane Library were searched to compare the efficacy and safety of short-term DAPT (6 months or less) with long-term DAPT (12 months or more) in patients implanted with new-generation drug-eluting stents in East Asian from inception to September 2020. The primary efficacy outcome was all-cause death, the primary safety outcome was major bleeding, and the secondary outcomes included cardiovascular death, myocardial infarction, definite or possible stent thrombosis, and stroke. A total of 6 randomized controlled trials with 15,688 patients met inclusion criteria; there were no significant differences in the incidence of all-cause death [risk ratio (RR), 1.03; 0.76-1.39; P = 0.856)], cardiovascular death (RR, 0.83; 0.55-1.24; P = 0.361), myocardial infarction (RR, 0.97; 0.72-1.31; P = 0.853), definite or possible stent thrombosis (RR, 1.52; 0.83-2.78; P = 0.170), and stroke (RR, 0.90; 0.61-1.31; P = 0.574) between short-term and long-term DAPTs. However, there was a significant difference in the risk of major bleeding (RR, 0.64; 0.49-0.85; P = 0.002) between the 2 groups. Compared with long-term DAPT, the short-term DAPT can reduce the risk of major bleeding without increasing the risk of death or ischemia for East Asians (Registered by PROSPERO, CRD42020213266).

Leukocyte Rho kinase activity and serum cystatin C affect cardiovascular events in acute coronary syndrome

OBJECTIVE

This study was designed to investigate the effects of leukocyte Rho kinase activity and serum Cystatin C (Cys C) on cardiovascular events in patients with acute coronary syndrome (ACS).

METHODS

A total of 48 patients with ST-segment elevation myocardial infarction (STEMI), 23 patients with non-ST-segment elevation myocardial infarction (NSTEMI), 25 patients with unstable angina (UA) and 20 patients with no-acute coronary syndrome as control from January 2017 to June 2018 in Tianyou Hospital affiliated to Wuhan University of Science and Technology were selected in this study. Western blot was used to detect the leukocyte Rho kinase activity and Elisa kit was used to measure serum Cys C. Univariate and multivariate analysis were used to analyze the influencing factors of cardiovascular events in ACS patients.

RESULTS

The activity of leukocyte Rho kinase and serum Cys C were gradually reduced in the STEMI, NSTEMI and UA patients, but all significantly higher than that in No-ASC patients, and there was a positive correlation between leukocyte Rho kinase activity and serum Cys C in ACS patients (r = 0.516, P < .001). The activity of leukocyte Rho kinase was positively correlated with the levels of serum TNF-α (r = 0.634, P < .001), IL-6 (r = 0.578, P < .001), IL-8 (r = 0.582, P < .001) in ACS patients, and the level of Cys C was positively correlated with the levels of serum TNF-α (r = 0.634, P < .001), IL-6 (r = 0.578, P < .001), IL-8 (r = 0.582, P < .001) in ACS patients. Univariate and multivariate analysis showed that the leukocyte Rho kinase activity (HR = 2.994, 95%CI = 1.328-6.054, P < .0001) and the levels of serum Cys C (HR = 1.692, 95%CI = 1.028-2.124, P < .0001) were independent influencing factors of cardiovascular events in ACS patients.

CONCLUSION

The leukocyte Rho kinase activity and serum Cystatin C are high in acute coronary syndrome patients, and are the independent influencing factors of cardiovascular events in ACS patients.

Sonothrombolysis in ST-Segment Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

BACKGROUND

Preclinical studies have demonstrated that high mechanical index (MI) impulses from a diagnostic ultrasound transducer during an intravenous microbubble infusion (sonothrombolysis) can restore epicardial and microvascular flow in acute ST-segment elevation myocardial infarction (STEMI).

OBJECTIVES

This study tested the clinical effectiveness of sonothrombolysis in patients with STEMI.

METHODS

Patients with their first STEMI were prospectively randomized to either diagnostic ultrasound-guided high MI impulses during an intravenous Definity (Lantheus Medical Imaging, North Billerica, Massachusetts) infusion before, and following, emergent percutaneous coronary intervention (PCI), or to a control group that received PCI only (n = 50 in each group). A reference first STEMI group (n = 203) who arrived outside the randomization window was also analyzed. Angiographic recanalization before PCI, ST-segment resolution, infarct size by magnetic resonance imaging, and systolic function (LVEF) at 6 months were compared.

RESULTS

ST-segment resolution occurred in 16 (32%) high MI PCI versus 2 (4%) PCI-only patients before PCI, and angiographic recanalization was 48% in high MI/PCI versus 20% in PCI only and 21% in the reference group (p < 0.001). Infarct size was reduced (29 ± 22 g high MI/PCI vs. 40 ± 20 g PCI only; p = 0.026). LVEF was not different between groups before treatment (44 ± 11% vs. 43 ± 10%), but increased immediately after PCI in the high MI/PCI group (p = 0.03), and remained higher at 6 months (p = 0.015). Need for implantable defibrillator (LVEF ≤30%) was reduced in the high MI/PCI group (5% vs. 18% PCI only; p = 0.045).

CONCLUSIONS

Sonothrombolysis added to PCI improves recanalization rates and reduces infarct size, resulting in sustained improvements in systolic function after STEMI. (Therapeutic Use of Ultrasound in Acute Coronary Artery Disease; NCT02410330).

Chinese herbal injections for unstable angina pectoris: A protocol for systematic review and network meta-analyses

BACKGROUND

Chinese herbal injections (CHIs) have been commonly used in the treatment of unstable angina pectoris (UAP) in China. However, there is no consensus or evidence on how to select CHIs for patients with UAP. The choice often depends on the personal experience or preference of clinician. This study aims to compare the effect of different CHIs for UAP using Bayesian network meta-analysis (NMA).

METHODS

A systematic search will be conducted in PubMed, the Cochrane Central Register of Controlled Trials, Embase, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, and Wanfang Data from inception to February 2018. We will include randomized controlled trials (RCT) regarding CHIs in the treatment of UAP. Quality of included RCTs will be assessed according to the Cochrane Handbook 5.1.0. A Bayesian NMA will be performed with WinBUGS 14 to compare the efficacy of different CHIs. GRADE will be used to assess the quality of evidence.

RESULTS

The results of this NMA will be submitted to a peer-reviewed journal for publication.

CONCLUSION

Our study will generate evidence for CHIs in the treatment of UAP and help clinicians make more accurate therapeutic schedule. In addition, it might provide suggestions for Chinese medicine clinical practice or guideline.

Relationship Between Continuity of Ambulatory Care and Risk of Emergency Department Episodes Among Older Adults

STUDY OBJECTIVE

We determine whether visit patterns indicative of higher continuity are related to a lower risk of presenting at the emergency department (ED) among older adults.

METHODS

This study was a survival analysis between 2011 and 2013 of a 20% random sample of fee-for-service Medicare beneficiaries aged 66 years or older. Ambulatory visit patterns were measured starting in 2011 for up to 24 months using 2 continuity metrics measured on a 0 to 1 scale-Continuity of Care (COC) score and the Usual Provider Continuity (UPC) score. The composite outcome of an ED episode was defined as occurrence of an ED visit with discharge home, an observation stay, or hospital admission. Time-dependent Cox proportional hazards regression models controlled for patient demographic characteristics, comorbidities, previous use, and regional factors, with censoring for death or occurrence of the composite outcome. In a secondary analysis, continuity was measured in the 12 months preceding an ED episode to test whether it was associated with type of ED episode.

RESULTS

The relative rate of ED episodes decreased approximately 1% for every 0.1-point increase in the COC score (adjusted hazard ratio 0.99; 95% confidence interval 0.99 to 0.99; P<.001) and 2% for every 0.1-point increase in the UPC score (adjusted hazard ratio 0.98; 95% CI 0.98 to 0.99; P<.001), or up to a 10% lower rate between the lowest and highest COC score and a 20% lower rate for the UPC score. Among beneficiaries with an ED episode, higher continuity was associated with a 1% lower risk of observation stay but a 3% to 4% higher risk of hospital admission relative to an ED visit with discharge home.

CONCLUSION

Ambulatory visit patterns exhibiting more continuity were associated with a lower rate of ED utilization for older adults with fee-for-service Medicare coverage. The association of higher continuity with lower risk of ED use but differences in outcome when an ED visit does occur may reflect more appropriate referral to the ED when outpatient management is no longer adequate.

Establishment of a hybrid risk model to predict major cardiac adverse events in patients with non-ST-elevation acute coronary syndromes

The present study aimed to generate a hybrid risk model for the prediction of major cardiac adverse events (MACE) in patients with non-ST-elevation acute coronary syndromes (NSTE-ACS), by combining the Global Registry of Acute Coronary Events (GRACE) scoring system and the plasma concentration of N-terminal of the prohormone brain natriuretic peptide (lgNT-proBNP). A total of 640 patients with NSTE-ACS were randomly divided into either the model-establishing group (409 patients) or the prediction model group (231 patients). The clinical endpoint event was MACE, including cardiogenic death, myocardial infarction and heart failure-induced readmission. Among the 409 patients in the model-establishing group, 26 (6.6%) experienced MACE. The hybrid risk model was calculated using the following equation: Hybrid risk model = GRACE score + 20 × logarithm (lg)NT-proBNP + 15, in which the area under the receiver operating curves (ROCs) for the GRACE score and lgNT-proBNP were 0.807 and 0.798, respectively. From the equation, the area under the ROC for the hybrid risk model was 0.843; thus suggesting that the hybrid risk model may be better able to predict the occurrence of MACE compared with either of its components alone. Following re-stratification, 6% of patients in the hybrid risk model were re-grouped. A total of 15 patients in the prediction model group experienced MACE (6.5%). The areas under the ROCs for the hybrid risk model and the GRACE scores for the prediction model group were 0.762 and 0.748, respectively. The results of the present study suggested that the lgNT-proBNP and GRACE score-established hybrid risk model may improve the accuracy by which MACE are predicted.

STEMI Outcomes in Guangzhou and Hong Kong: Two-Centre Retrospective Interregional Study

Background and Objectives

Healthcare systems are organized very differently in Hong Kong (HK) and Guangzhou (GZ). This study compared managements of the emergency departments (ED) and one-year mortalities of ST-segment elevation myocardial infarction (STEMI) patients in two teaching hospitals in Guangzhou and Hong Kong.

Methods

Retrospective observational study of STEMI mortalities and treatments in the Prince of Wales Hospital (PWH) and the Second Affiliated Hospital of Guangzhou Medical University (AHGZMU), was conducted between January and December 2010. The primary outcome was one-year all cause mortality.

Results

Univariate analysis of 76 cases from PWH and 111 cases from AHGZMU showed similar clinical characteristics, except for lower proportions of males (74% vs 92%, P = 0.002), hyperlipidemia (5% vs 25%, P<0.001), and Killip class I (56% vs 91%; P<0.001) in AHGZMU. The onset-to-door time of STEMI patients in AHGZMU was longer than in PWH (median 205 min [(IQR: 95–432) vs 120 min (IQR: 55–225), P = 0.001]. In AHGZMU, 85 (77%) patients received primary percutaneous coronary intervention (PPCI) as the main reperfusion treatment, whereas 18 (24%) received PPCI and 51 (67%) patients received thrombolytic therapy in PWH. Overall the one-year mortality in AHGZMU was 20%, whilst in PWH it was 14% (P = 0.436). The standardized one-year all-cause mortality ratios for AHGZMU and PWH were comparable (18.7 vs. 18.2%, P = 0894). Independent predictors of one-year mortality included older age (>67 years) and hyperglycemia (>10 mmol/L). Aged over 65 years, presence of anterior wall infarct, body weight ≤65 kg, SBP <100 mmHg at ED and glucose level >10 mmol/L were the independent predictors of in-hospital MACE.

Conclusion

There was no statistically significant difference between the standardized one-year all-cause mortalities of STEMI patients in the setting mainly using thrombolysis with shorter door-to-treatment time and the setting mainly using PCI with longer door-to-treatment time. Aged over 67 years and glucose level over 10 mmol/L were the independent predictors of one-year mortality. Older age, presence of anterior wall infarct, lower body weight, lower SBP at ED and hyperglycemia were the independent predictors of in-hospital MACE.

The change in platelet count in patients with acute coronary syndrome 6 months after coronary stent implantation

After coronary stent implantation, patients with acute coronary syndrome commonly take clopidogrel, and few patients develop severe thrombocytopenia related to clopidogrel. However, we found in our clinical practice that platelet counts of most patients decrease slightly after taking clopidogrel for 6 months. To address this discrepancy, we studied the change in platelet count after coronary stent implantation in patients with acute coronary syndrome. Ninety-five patients were selected for this study, and their prestent platelet counts were compared with those 6 months after stent implantation. All patients had low/intermediate-risk non-ST segment elevation myocardial infarction/unstable angina and underwent delayed coronary interventional treatment. No patient suffered from thrombocytopenia (<100 × 10⁹/l) during the 6-month observation period. Six months after stent implantation, platelet counts significantly decreased in the majority of patients (73/95, 76.9%) and increased only in the minority of patients (22/95, 23.1%). A multivariate analysis showed that the change in platelet count was positively correlated with the change in leukocyte and fibrinogen value, and negatively correlated with number of stents. The platelet count decreased in the majority of patients after stent implantation, which may be caused by the removal of stress factors or stent-related platelet consumption. Clopidogrel may partly prevent stent-related platelet consumption.

Emergency drug kits: pharmacological and technical considerations

The risk for complications while providing dental procedures is greatest when caring for patients having significant medical compromise. It is comforting that significant adverse events can generally be prevented by careful preoperative assessment, along with attentive intraoperative monitoring and support. Nevertheless, the office team must be prepared to manage untoward events should they arise. This continuing education article will address basic emergency drugs that should be available in all dental practices and additional agents that become essential for those practices providing various levels of procedural sedation or general anesthesia.

N-terminal pro-brain natriuretic peptide and cardiac troponin I for the prognostic utility in elderly patients with severe sepsis or septic shock in intensive care unit: A retrospective study

BACKGROUNDS

Using biomarkers to predict mortality in patient with severe sepsis or septic shock is of importance, as these patients frequently have high mortality and unsatisfied outcome. N-terminal pro-brain natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI) play extremely important roles in prognostic value in the mortality of severe sepsis and septic shock.

AIMS

The present study was retrospectively designed to evaluate the predicting mortality of NT-proBNP and cTnI in elderly patients with severe sepsis or septic shock administered in the intensive care unit (ICU) and also to evaluate whether the predicting ability of Acute Physiology and Chronic Health Evaluation II (APACHE-II) score or C-reactive protein (CRP) was increased in combination with the biomarkers.

PATIENTS AND METHODS

A cohort of 430 patients (aged ≥65 years) with severe sepsis or septic shock admitted to our ICU between October 2011 and December 2013 was included in the study. Patient data including clinical, laboratory, and survival and mortality were collected. All patients were examined with NT-proBNP, cTnI, CRP, and APACHE-II score and were categorized as the survived and deceased groups according to the outcome 30 days after ICU treatment.

RESULTS

The levels of NT-proBNP and cTnI (P < .01) or CRP (P < .05) were significantly higher in the deceased group than those in the survived group. The predicting mortality of APACHE-II score alone was low but largely improved, when it was combined with both NT-proBNP and cTnI (P < .05).

CONCLUSION

The alteration of NT-proBNP and cTnI levels strongly predicated the ICU prognosis in elderly patients with severe sepsis or septic shock. N-terminal pro-brain natriuretic peptide and cTnI were superior to CRP in predicting mortality. The predicting ability of APACHE-II score was improved only when combined with NT-proBNP and cTnI.

Nutritional status and coronary artery disease: a cross sectional study

BACKGROUND

Nutrition is among the most important factors influencing coronary artery disease.

OBJECTIVES

Here we aimed to study the nutritional status of patients with and without coronary artery disease (CAD).

PATIENTS AND METHODS

We performed a cross-sectional study on 600 patients referred to a cardiology clinic with the signs of ACS. The patients were then classified in to two groups (CAD group and the normal group) based on angiographic findings. The amount of nutritional profile was questioned from all participants.

RESULTS

Men were more often diagnosed with CAD compared to women (198/362 vs. 102/238; P < 0.01). Patients with coronary artery disease were mostly older, smoker, coffee and black tea drinker had a higher BMI and more frequently diagnosed with hypertension, hyperlipidemia and diabetes. On the other hand, green tea consumption was seen more in women (92/238 vs. 115/362; P < 0.05) and those with regular physical activity (119/299 vs. 88/301; P < 0.01). Backward regression modeling was employed to study the predictors of CAD. Type of tea and meat remained as one the most important nutritional factors predicting CAD.

CONCLUSIONS

White mean and type of tea were the most important predictors of CAD. Dietary prevention strategies from childhood could prevent early CAD.

Effects of Moderate Glycemic Control in Type II Diabetes With Insulin on Arterial Blood Gas Parameters Following Coronary Artery Bypass Graft Surgery

Background:

Coronary artery bypass grafting (CABG) is one of the common surgeries in patients with coronary artery disease (CAD). It is more probable for patients with diabetes to undergo surgeries due to CAD and they have a higher mortality rate compared to the others

Objectives:

The aim of the present study was to assess the effects of insulin infusion therapy on blood gas parameters in two groups of patients, eligible for CABG, defined as A: well controlled diabetes (HbA1C < 7%) and B: non-diabetic patients.

Patients and Methods:

We followed two groups of patients, defined as patients with and without diabetes who were candidates for CABG, between March 2010 and March 2012. Patients with diabetes underwent moderate or semi-tight glycemic control, using continuous intravenous insulin infusion.

Results:

There were 13 male and 18 female subjects in the on-diabetic group and 11 male and 7 female patients in the controlled diabetic group. There was no significant difference between the studied participants regarding age, cardiac ejection fraction, blood pH and PO₂ and PCO₂ levels.

Conclusions:

CABG surgery adversely affects arterial blood gas (ABG) determinations. On the other hand, findings showed there is no significant difference in the ABG parameters between patients with well controlled diabetes and the ones without.

The association between pretest probability of coronary artery disease and stress test utilization and outcomes in a chest pain observation unit

OBJECTIVES

Cardiology consensus guidelines recommend use of the Diamond and Forrester (D&F) score to augment the decision to pursue stress testing. However, recent work has reported no association between pretest probability of coronary artery disease (CAD) as measured by D&F and physician discretion in stress test utilization for inpatients. The author hypothesized that D&F pretest probability would predict the likelihood of acute coronary syndrome (ACS) and a positive stress test and that there would be limited yield to diagnostic testing of patients categorized as low pretest probability by D&F score who are admitted to a chest pain observation unit (CPU).

METHODS

This was a prospective observational cohort study of consecutively admitted CPU patients in a large-volume academic urban emergency department (ED). Cardiologists rounded on all patients and stress test utilization was driven by their recommendations. Inclusion criteria were as follows: age>18 years, American Heart Association (AHA) low/intermediate risk, nondynamic electrocardiograms (ECGs), and normal initial troponin I. Exclusion criteria were as follows: age older than 75 years with a history of CAD. A D&F score for likelihood of CAD was calculated on each patient independent of patient care. Based on the D&F score, patients were assigned a priori to low-, intermediate-, and high-risk groups (<10, 10 to 90, and >90%, respectively). ACS was defined by ischemia on stress test, coronary artery occlusion of ≥70% in at least one vessel, or elevations in troponin I consistent with consensus guidelines. A true-positive stress test was defined by evidence of reversible ischemia and subsequent angiographic evidence of critical stenosis or a discharge diagnosis of ACS. An estimated 3,500 patients would be necessary to have 1% precision around a potential 0.3% event rate in low-pretest-probability patients. Categorical comparisons were made using Pearson chi-square testing.

RESULTS

A total of 3,552 patients with index visits were enrolled over a 29-month period. The mean (±standard deviation [SD]) age was 51.3 (±9.3) years. Forty-nine percent of patients received stress testing. Pretest probability based on D&F score was associated with stress test utilization (p<0.01), risk of ACS (p<0.01), and true-positive stress tests (p=0.03). No patients with low pretest probability were subsequently diagnosed with ACS (95% CI=0 to 0.66%) or had a true-positive stress test (95% CI=0 to 1.6%).

CONCLUSIONS

Physician discretionary decision-making regarding stress test use is associated with pretest probability of CAD. However, based on the D&F score, low-pretest-probability patients who meet CPU admission criteria are very unlikely to have a true-positive stress test or eventually receive a diagnosis of ACS, such that observation and stress test utilization may be obviated.

Chinese patent medicine Xuefu Zhuyu capsule for the treatment of unstable angina pectoris: A systematic review of randomized controlled trials

BACKGROUND

Xuefu Zhuyu Capsule (XFZY) has been commonly used for relieving chest pain in patients with coronary heart disease (CHD). Randomized controlled trials (RCTs) on XFZY in treating unstable angina (UA) have not been systematically reviewed.

OBJECTIVE

This study aims to provide a PRISMA-compliant systematic review to evaluate the efficacy of XFZY in treating UA.

METHODS

An extensive search of 7 medical databases was performed up to June 2013. RCTs involving XFZY or combined with conventional drugs versus conventional drugs were identified. Meta-analysis was performed to evaluate the cardiovascular effects of XFZY. Rev Man 5.0 was used for data analysis.

RESULTS

8 RCTs were included in this review. Statistical analysis of the results showed that XFZY combined with conventional drugs had significant effect on relieving angina symptoms (RR: 1.26 [1.16, 1.38]; P<0.00001) and improving ECG (RR: 1.20 [1.04, 1.38]; P=0.01) compared with conventional drugs alone. No severe adverse events were reported.

CONCLUSIONS

XFZY combined with conventional drugs appears to have potential cardiovascular effects in treatment of UA with few adverse events. However, further rigorous designed trials are still needed.

Emergency medicine in the United Arab Emirates

It has been a decade since emergency medicine was recognized as a specialty in the United Arab Emirates (UAE). In this short time, emergency medicine has established itself and developed rapidly in the UAE. Large, well-equipped emergency departments (EDs) are usually located in government hospitals, some of which function as regional trauma centers. Most of the larger EDs are staffed with medically or surgically trained physicians, with board-certified emergency medicine physicians serving as consultants overseeing care.Prehospital care and emergency medical services (EMS) operate under the auspices of the police department. Standardized protocols have been established for paramedic certification, triage, and destination decisions. The majority of ambulances offer basic life support (BLS/Type 2) with a growing minority offering advanced life support (ALS/Type 3).Medicine residency programs were established 5 years ago and form the foundation for training emergency medicine specialists for UAE.This article describes the full spectrum of emergency medicine in the UAE: prehospital care, EMS, hospital-based emergency care, training in emergency medicine, and disaster preparedness. We hope that our experience, our understanding of the challenges faced by the specialty, and the anticipated future directions will be of importance to others advancing emergency medicine in their region and across the globe.

Emergency Department vancomycin use: dosing practices and associated outcomes

BACKGROUND

Emergency Department (ED) dosing of vancomycin and its effect on outcomes has not been examined.

STUDY OBJECTIVE

To describe current vancomycin dosing practices for ED patients, focusing on patient factors associated with administration, dosing accuracy based on patient body weight, and clinical outcomes.

METHODS

Single-center, retrospective cohort study of vancomycin administered in the ED over 18 months in an academic, tertiary care ED. Data were collected on 4656 patients. Data were analyzed using a generalized estimating equations model to account for multiple doses being administered to the same patient.

RESULTS

The ED dose was continued, unchanged, in 2560 admitted patients (83.8%). The correct dose was given 980 times (22.1%), 3143 doses (70.7%) were underdosed, and 318 were overdosed (7.2%). Increasing weight was associated with underdosing (adjusted odds ratio 1.52 per 10 kg body weight, p < 0.001). Patients who received doses of vancomycin > 20 mg/kg had longer hospital length of stay (p = 0.005); were more likely to spend ≥ 3 days in the hospital (odds ratio [OR] 1.49; 95% confidence interval [CI] 1.12-1.98, p = 0.006); and more likely to die (OR 1.88; 95% CI 1.22-2.90, p = 0.004).

CONCLUSION

In this largest study to date examining ED vancomycin dosing, vancomycin was commonly given. Dosing outside the recommended range was frequent, and especially prevalent in patients with a higher body weight. The ED dose of vancomycin was frequently continued as an inpatient, regardless of dosing accuracy. There is significant room for improvement in dosing accuracy and indication. Vancomycin dosing in the ED may also affect clinical outcomes.

Predictive value of high-sensitivity troponin I and D-dimer assays for adverse outcome in patients with acute pulmonary embolism

High-sensitivity troponin (hs-cTn) assays enable the troponin cutoff value to be lowered, resulting in an increase of sensitivity at the cost of specificity. In the present study, the risk of a short-term adverse outcome was assessed in patients with acute pulmonary embolism (PE) using high-sensitivity troponin I (hs-cTnI). We used a cutoff value of 0.1 ng/ml in accordance with current guidelines for unstable angina (UA)/non-ST-segment elevation myocardial infarction (NSTEMI), although the detection limit of the troponin assay is lower. In addition, the risk of an adverse outcome in patients with acute PE was investigated with respect to initial D-dimer serum concentrations. In 65 patients with confirmed acute PE, hs-cTnI and D-dimer values were measured. Adverse clinical outcome was defined as cardiogenic shock, cardiopulmonary resuscitation, mechanical ventilation, vasopressor therapy, thrombolysis, catheter intervention or mortality within 60 days of PE. Patients with acute PE and serum hs-cTnI values >0.1 ng/ml showed significantly higher D-dimer concentrations (P= 0.0467) and a 5-fold increased risk of an adverse clinical outcome [odds ratio (OR), 4.9; 95% confidence interval (CI), 1.28-18.66; P=0.0235] compared with patients with acute PE and hs-cTnI values <0.1 ng/ml. In patients with acute PE suffering from adverse clinical outcome, D-dimer concentrations were significantly elevated compared with those in patients with acute PE without adverse clinical outcome (P=0.02). In patients with acute PE, a hs-cTnI cutoff value of 0.1 ng/ml, which is identical to the recommended cutoff value of NSTEMI, may identify patients with a 5-fold increased risk of a short-term adverse outcome. D-dimer values are significantly higher in PE patients with elevated hs-cTnI values as well as in patients with an adverse outcome.

How Safe Is the Outpatient Management of Patients with Acute Chest Pain and Mildly Increased Cardiac Troponin Concentrations?

BACKGROUND

The appropriate management of patients discharged from the emergency department (ED) with increased high-sensitivity cardiac troponin T (hs-cTnT) but normal or borderline-high conventional cardiac troponin concentrations is unknown.

METHODS

We investigated 643 consecutive ED patients with acute chest pain who had been discharged for outpatient management after acute myocardial infarction (AMI) had been ruled out by serial measurements of conventional cardiac troponin. hs-cTnT was measured blindly, and we calculated the rates of all-cause mortality (primary endpoint) and subsequent AMI (secondary endpoint) at 30, 90, and 360 days.

RESULTS

hs-cTnT concentrations were increased (&gt;14 ng/L) in 114 patients (18%) but &lt;30 ng/L in 95% of these patients. Of those 114 patients, 96 (84%) had an adjudicated noncoronary cause of chest pain. Thirty-day mortality (95% CI) was 0.9% (0.1%–6.1%), 90-day mortality was 2.7% (0.9%–8.1%), and 360-day mortality was 5.2% (2.2%–11.9%) in patients with increased hs-cTnT; respective rates (95% CI) of AMI were 0.0%, 1.9% (0.5%–7.2%), and 7.6% (3.7%–15.3%). Increased hs-cTnT was associated with increased mortality and AMI at 90 days (P = 0.006 and P = 0.081, respectively) and 360 days (P = 0.001 for both).

CONCLUSIONS

hs-cTnT is a strong prognosticator of intermediate and long-term mortality and AMI in low-risk patients discharged from the ED after AMI has been ruled out. The relatively low rate of 30-day events may suggest that patients without acute coronary syndrome and small increases in cardiac troponin are in need of further investigations and treatments, but not necessarily immediate hospitalization.

Combination of copeptin and troponin assays to rapidly rule out non-ST elevation myocardial infarction in the emergency department

OBJECTIVES

The aim of this study was to analyze the diagnostic accuracy and the clinical usefulness of the combination of troponin I (cTnI) and copeptin measured at presentation with an automated assay to rapidly rule out non-ST elevation myocardial infarction (NSTEMI) in patients with suspected cardiac chest pain presenting to an emergency department (ED).

METHODS

This study was an ancillary analysis of a prospective observational study. Copeptin and cTnI levels were sampled at presentation in 641 consecutive patients admitted to the ED for chest pain with onset within the last 12 hours and without ST elevation on a 12-lead electrocardiogram (ECG). Copeptin was measured with an automated assay and troponin with conventional assay. The performance of a combination of cTnI and copeptin for NSTEMI diagnosis was studied, the clinical utility was assessed by multivariate analysis, and an area under the curve (AUC) calculation was used to determine accuracy.

RESULTS

NSTEMI was diagnosed in 95 patients (15%). The sensitivity and negative predictive value (NPV) of the combination of copeptin and cTnI measures were 90.4% (95% confidence interval [CI] = 88.2% to 92.7%) and 97.6% (95% CI = 96.4% to 98.7%) versus 55.3% (95% CI = 51.5% to 59.2%) and 92.8% (95% CI = 90.8% to 94.8%) with cTnI alone. The AUC of the combination of copeptin and cTnI was 0.89 (95% CI = 0.85% to 0.92%) and was significantly higher than the AUC of cTnI alone (0.77, 95% CI = 0.72% to 0.82%, p < 0.05). The patient classification was slightly improved when copeptin was added to the usual diagnostic tools used for NSTEMI management.

CONCLUSIONS

In this study, determination of copeptin, in addition to cTnI, improves early diagnostic accuracy of NSTEMI. However, the sensitivity of this combination even using a conventional troponin assay remains insufficient to safely rule out NSTEMI at the time of presentation.

The impact of increased age on outcome from a strategy of early invasive management and revascularisation in patients with acute coronary syndromes: retrospective analysis study from the ACACIA registry

OBJECTIVE

To evaluate the impact of increased age on outcome from a strategy of early invasive management and revascularisation in patients with acute coronary syndromes (ACS).

DESIGN

Retrospective analysis of a national Acute Coronary Syndrome registry (ACACIA).

SETTING

Multiple Australian (n=39) centres; 25% rural, 52% with onsite cardiac surgery.

PATIENTS

Unselected consecutive patients admitted with confirmed ACS, total n=2559, median 99 per centre.

INTERVENTIONS

Management was at the discretion of the treating physician. Analysis of outcome based on age >75 years was compared using Cox proportional hazard with a propensity model to adjust for baseline covariates.

MAIN OUTCOME MEASURES

Primary outcome was all-cause mortality. Secondary outcomes were bleeding and a composite of any vascular event or unplanned readmission.

RESULTS

Elderly patients were more likely to present with high-risk features yet were less likely to receive evidence-based medical therapies or receive diagnostic coronary angiography (75% vs 49%, p<0.0001) and early revascularisation (50% vs 30%, p<0.0001). Multivariate analysis found early revascularisation in the elderly cohort to be associated with lower 12-month mortality hazard (0.4 (0.2-0.7)) and composite outcome (0.6 (0.5-0.8)). Propensity model suggested a greater absolute benefit in elderly patients compared to others.

CONCLUSIONS

Following presentation with ACS, elderly patients are less likely to receive evidence-based medical therapies, to be considered for an early invasive strategy and be revascularised. Increasing age is a significant barrier to physicians when considering early revascularisation. An early invasive strategy with revascularisation when performed was associated with substantial benefit and the absolute accrued benefit appears to be higher in elderly patients.

Recognition and management of complications during moderate and deep sedation. Part 2: cardiovascular considerations

The risk for cardiovascular complications while providing any level of sedation or general anesthesia is greatest when caring for patients already medically compromised. It is reassuring that significant untoward events can generally be prevented by careful preoperative assessment, along with attentive intraoperative monitoring and support. Nevertheless, providers must be prepared to manage untoward events should they arise. This continuing education article will review cardiovascular complications and address their appropriate management.

Diagnostic importance of platelet parameters in patients with acute coronary syndrome admitted to a tertiary care hospital in southwest region, Saudi Arabia

OBJECTIVE

Identifying risk factors for acute coronary syndrome (ACS) is important for both diagnostic and prognostic purposes. Abnormal platelet parameters, mainly platelet count (PC), mean platelet volume (MPV) and platelet distribution width (PDW) are thought to be among these risk factors. In this study, the associations between PC, MPV and PDW and ACS were investigated in patients admitted to the tertiary care hospital in the south west region of Saudi Arabia.

MATERIALS AND METHODS

A retrospective cohort of 212 patients with the diagnosis of ACS admitted to Aseer Central Hospital during the period extending from February 1, 2008 to October 31, 2008 were included. The control group consisted of 49 matched subjects who were admitted for chest pain investigation and subsequently found to be non-cardiac chest pain after performing relevant investigations. Blood samples were taken at the time of admission for platelet parameters. Statistical analysis was made using SPSS software and P-values were considered significant if <0.05.

RESULTS

A total of 212 patients with acute coronary syndrome (80 patients with MI and 132 patients with UA) and 49 matched controls were studied. The PC was not statistically different among the three groups (283.3 ± 94.8 × 10(9) L(-1) for MI cases, 262 ± 60.8 × 10(9) L(-1) for UA cases and 275.8 ± 58.9 × 10(9) L(-1) for controls). The MPV was significantly larger in MI cases compared to controls (8.99 ± 1.5 fl vs. 8.38 ± 0.51 fl, respectively, P < 0.009), similarly, the MPV was significantly larger in UA cases compared to controls (9.23 ± 1.19 fl vs. 8.38 ± 0.51 fl, respectively, P < 0.001). The PDW was significantly higher in MI cases compared to controls (15.88 ± 1.5 fl vs. 11.96 ± 1.8 fl, respectively, P < 0.001), similarly, the PDW as also significantly larger in UA cases compared to controls (18.1 ± 18 fl vs. 11.96 ± 1.8 fl, respectively, P < 0.019).

CONCLUSION

Platelet parameters mainly MPV and PDW are readily available and relatively simple and inexpensive laboratory tests which we detected to be significantly raised in patients who have suffered an acute coronary syndrome compared with controls.

N-terminal pro B-type natriuretic peptide identifies patients with chest pain at high long-term cardiovascular risk

BACKGROUND

Little is known about the long-term prognostic value of N-terminal pro B-type natriuretic peptide (NT-proBNP) and C-reactive protein (CRP) in low-risk patients with chest pain.

METHODS

Between June 1997 and January 2000, a standard rule-out protocol was performed in patients presenting to the emergency department within 6 hours of onset of chest pain with a normal or nondiagnostic electrocardiogram (ECG) on admission at the Academic Medical Center Amsterdam, VU University Medical Center Amsterdam and Medical Center Alkmaar, The Netherlands. Patients with acute coronary syndrome were identified by troponin T, recurrent angina, and serial ECGs. CRP and NT-proBNP on admission were measured using standardized methods.

RESULTS

A total of 524 patients were included (145 with acute coronary syndrome and 379 with rule-out acute coronary syndrome). Long-term follow-up was successfully carried out in 96% of the study population. Death occurred in 78 patients (15%), 43 (11%) in the rule-out acute coronary syndrome group and 35 (24%) in the acute coronary syndrome group (P<.001). In the rule-out acute coronary syndrome group, 21 patients (42%) died of a cardiovascular cause compared with 24 patients (69%) in the acute coronary syndrome group (P<.001). In multivariate Cox regression analysis, age more than 65 years, previous myocardial infarction, known chronic heart failure, a nondiagnostic ECG on admission, and elevated NT-proBNP levels (>87 pg/mL, as derived from the receiver operating characteristic curve) were independent predictors of long-term cardiovascular mortality in the rule-out acute coronary syndrome group. In the acute coronary syndrome group, these predictors were age more than 65 years, documented coronary artery disease, and elevated NT-proBNP levels. Elevated levels of CRP were an independent predictor for cardiovascular mortality in patients with rule-out acute coronary syndrome at 3-year follow-up only. In patients with rule-out acute coronary syndrome with normal CRP and NT-proBNP levels, the cardiovascular mortality incidence rate was 4.7 per 1000 person-years, compared with a death rate of 20 in patients with both biomarkers elevated, which was comparable to the 17.9 per 1000 person-years incidence rate in patients with acute coronary syndrome.

CONCLUSION

A positive biomarker panel discriminates patients with rule-out acute coronary syndrome chest pain with a normal or nondiagnostic ECG who have a high risk for long-term cardiovascular mortality.

Stress-only Tc-99m myocardial perfusion imaging in an emergency department chest pain unit

BACKGROUND

Stress-only myocardial perfusion imaging (MPI) saves time by eliminating rest imaging, which is important for emergency department (ED) throughput but has not been studied in an ED population.

STUDY OBJECTIVE

To determine the prognosis of a normal stress-only MPI study compared to a normal rest-stress MPI and establish its effectiveness in an ED setting.

METHODS

All patients evaluated in the ED over 6.5 years who underwent a stress-only technetium-99m gated MPI were compared to those who had a rest-stress study. All-cause mortality was determined using the Social Security Death Index. Survival was analyzed in patients with normal and abnormal MPI results.

RESULTS

A total of 4145 studies (2340 stress-only, 1805 rest-stress) were performed. Patients' average age was 57.9 years, 38.5% were male, and most had an intermediate or low pretest risk of coronary artery disease (87.7%). Average follow-up was 35.9 ± 20.9 months. In patients with normal perfusion, at 1 year of follow-up there were 11 deaths in the stress-only group (0.5% 1-year mortality), and 13 deaths in the rest-stress cohort (1.1% 1-year mortality). At the end of follow-up, the stress-only group had a lower all-cause mortality (p < 0.0001) and similar risk adjusted all-cause mortality (p = 0.10) than the rest-stress cohort. Patients with abnormal perfusion demonstrated the expected differential prognosis based on total perfusion deficits in both groups.

CONCLUSIONS

A normal stress-only MPI study has a benign 1-year prognosis similar to a rest-stress study when performed in the ED. The ability to triage patients more rapidly and reduce radiation exposure represents an attractive alternative for low-risk patients.

A systematic review on pharmacogenetics in cardiovascular disease: is it ready for clinical application?

Pharmacogenetics is the search for heritable genetic polymorphisms that influence responses to drug therapy. The most important application of pharmacogenetics is to guide choosing agents with the greatest potential of efficacy and smallest risk of adverse drug reactions. Many studies focusing on drug-gene interactions have been published in recent years, some of which led to adaptation of FDA recommendations, indicating that we are on the verge of the clinical application of genetic information in drug therapy. This systematic review provides a comprehensive overview of the current knowledge on pharmacogenetics of all major drug classes currently used in the treatment of cardiovascular diseases.

High-sensitivity versus conventional troponin in the emergency department for the diagnosis of acute myocardial infarction

Introduction

Recently, newer assays for cardiac troponin (cTn) have been developed which are able to detect changes in concentration of the biomarker at or below the 99th percentile for a normal population. The objective of this study was to compare the diagnostic performance of a new high-sensitivity troponin T (HsTnT) assay to that of conventional cTnI for the diagnosis of acute myocardial infarction (AMI) according to pretest probability (PTP).

Methods

In consecutive patients who presented to our emergency departments with chest pain suggestive of AMI, levels of HsTnT were measured at presentation, blinded to the emergency physicians, who were asked to estimate the empirical PTP of AMI. The discharge diagnosis was adjudicated by two independent experts on the basis of all available data.

Results

A total of 317 patients were included, comprising 149 (47%) who were considered to have low PTP, 109 (34%) who were considered to have moderate PTP and 59 (19%) who were considered to have high PTP. AMI was confirmed in 45 patients (14%), 22 (9%) of whom were considered to have low to moderate PTP and 23 (39%) of whom were considered to have high PTP (P < 0.001). In the low to moderate PTP group, HsTnT levels ≥ 0.014 μg/L identified AMI with a higher sensitivity than cTnI (91%, 95% confidence interval (95% CI) 79 to 100, vs. 77% (95% CI 60 to 95); P = 0.001), but the negative predictive value was not different (99% (95% CI 98 to 100) vs. 98% (95% CI 96 to 100)). There was no difference in area under the receiver operating characteristic (ROC) curve between HsTnT and cTnI (0.93 (95% CI 0.90 to 0.98) vs. 0.94 (95% CI 0.88 to 0.97), respectively).

Conclusions

In patients with low to moderate PTP of AMI, HsTnT is slightly more useful than cTnI. Our results confirm that the use of HsTnT has a higher sensitivity than conventional cTnI.

Dosing of unfractionated heparin in obese patients with venous thromboembolism

BACKGROUND

Aggressive weight-based dosing guidelines help achieve prompt therapeutic anticoagulation in patients with venous thromboembolism (VTE). While obese patients with VTE face an increased risk of recurrence, physicians typically resist prescribing doses two to three times the usual dose because of concern about bleeding complications.

OBJECTIVE

To examine the use of unfractionated heparin in obese patients with VTE at an academic teaching hospital in order to document the extent and pattern of underprescribing in this high-risk patient population.

DESIGN

Three-year, cross-sectional consecutive case series.

PATIENTS

Adult inpatients with VTE and a body mass index ≥30 kg/m(2) who were treated with unfractionated heparin.

MEASUREMENTS

Time to achievement of therapeutic anticoagulation (activated partial thromboplastin time >60 s) and gap between recommended and prescribed heparin doses.

RESULTS

Time to attainment of therapeutic anticoagulation exceeded 24 h in 29% of study patients (n = 84) and exceeded 48 h in 14% of patients. In 75 patients (89%), the prescribed bolus dose fell below the recommended dose of 80 units/kg, and in 64 patients (76%) the initial continuous infusion fell more than 100 units/h below--in some cases more than 1000 units/h below--the recommended dose of 18 units/kg/h. There was a significant correlation between time to therapeutic anticoagulation and initial infusion dose (Spearman r = -0.27; p < 0.02). Each decrease of 1 unit/kg/h translated to a delay ranging from about 0.75 h to 1.5 h over the range of prescribed doses (6 to 22 units/kg/h).

CONCLUSIONS

A substantial proportion of obese patients treated with unfractionated heparin experienced a delay >24 h in achieving adequate anticoagulation, and the vast majority received an inadequate heparin bolus or initial continuous infusion (or both) according to current dosing guidelines.

Emerging oral antiplatelet therapies for acute coronary syndromes

Emergency department physicians, along with hospitalists and interventional cardiologists, provide first-line care for patients experiencing symptoms potentially associated with acute coronary syndromes (ACS). Because these health care providers encounter and manage patients with varying degrees of risk, a clear understanding of the modes of action, benefits, and limitations of various therapeutic options is crucial for achieving optimal outcomes in the acute-care setting. Oral antiplatelet therapy has a major role in the acute care of patients with suspected ACS due to the critical role of platelets in the pathophysiology of disease. The current standard-of-care oral antiplatelet therapy for ACS is aspirin in combination with a P2Y12 adenosine diphosphate (ADP) receptor antagonist, most commonly clopidogrel. Aspirin and P2Y12 antagonists have both demonstrated efficacy in reducing morbidity and mortality in patients with ACS, but are also associated with increased bleeding risk compared with controls. Additionally, despite dual oral antiplatelet therapy, patients remain at substantial residual risk for ischemic events due to thrombotic episodes driven by platelet activation pathways that are not inhibited by these agents, including the protease-activated receptor (PAR)-1 platelet activation pathway, stimulated by thrombin. Novel oral antiplatelet agents in advanced clinical development include a direct and more readily reversible P2Y12 antagonist, ticagrelor, as well as a new class of PAR-1 antagonists, which includes vorapaxar and atopaxar. Ticagrelor has shown a significant ischemic benefit and an increase in non-surgical bleeding over clopidogrel in the large phase 3 Platelet Inhibition and Patient Outcomes trial. Results of phase 2 trials with PAR-1 antagonists suggest that these agents may provide incremental reduction in ischemic events without a bleeding liability. This hypothesis is being evaluated in 2 large ongoing phase 3 trials with vorapaxar, including the Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome (TRA*CER) trial in patients with non-ST-segment elevation ACS.

Hyperglycaemia in critical illness is a risk factor for later development of type II diabetes mellitus

Hyperglycaemia caused by stress and inflammation is common during critical illness. We hypothesised that a latent glucose metabolism disturbance contributes to development of hyperglycaemia and that those patients have increased risk for diabetes. We included patients with sepsis, acute coronary syndrome and acute heart failure with no history of impaired glucose metabolism and divided them in the hyperglycaemia group (glucose ≥ 7.8 mmol/l) and normoglycaemia group. Patients were followed for 5 years. Follow-up was completed for 115 patients in the normoglycaemia group, of which 4 (3.5%) developed type 2 diabetes. In the hyperglycaemia group 51 patients finished follow-up and 8 (15.7%) developed type 2 diabetes. Relative risk in 5-year period for patients with hyperglycaemia was 4.51 for development of type 2 diabetes. Patients with hyperglycaemia during critical illness who are not diagnosed with diabetes before or during the hospitalisation should be considered a population at increased risk for developing diabetes.

ED to catheterization laboratory: a roundtable integrating trials with practice

BACKGROUND

Clinical trials are the foundation underlying clinical decision-making. However, stringent inclusion and exclusion criteria may reduce the generalizability of their results, especially for patients seen in the emergency department (ED). Guideline recommendations, based on clinical trials and pertinent registries, apply to broad populations, but not all patients cared for at the bedside fit the predefined categories that make guidelines practical. Furthermore, these documents may not incorporate the latest evidence. As a result, other factors (eg, individual patient characteristics, clinician experience, cost, regulatory labels, expert opinions) often result in clinical decision-making that varies from strict adherence to guideline recommendations.

OBJECTIVES

These challenges demonstrate a need to integrate clinical data and guidelines advice with actual ED practice in a manner that will be consistent with decisions made later in the continuum of care.

DISCUSSION

In recognition of these issues, a roundtable was convened in New York City on June 5, 2009, to discuss the implications of recent trials involving patients with non-ST-segment elevation acute coronary syndromes. Eight physicians, representing both emergency medicine and cardiology, shared information on advances and clinical trial results in antiplatelet treatment, guidelines, and other developments in patient care. This article is based on transcripts of their presentations and the ensuing discussions that were of particular importance for emergency physicians.

CONCLUSIONS

Although guidelines and clinical registries can provide broad direction for practice, there is no substitute for a prospective, multidisciplinary, institution-specific, consistent, evidence-based approach to patient management.

Troponin elevation in heart failure prevalence, mechanisms, and clinical implications

Circulating biomarkers have become increasingly important in diagnosing and risk stratifying patients with heart failure (HF). While the natriuretic peptides have received much focus, there is increasing interest in the role of circulating cardiac troponin (cTn) in detecting myocardial injury (often subclinical) in those with HF. Accumulating evidence suggests that patients with chronic and acute HF may have measurable levels of circulating cTn, whose detection and magnitude may have prognostic implications. Furthermore, as new, more sensitive cTn assays are being developed, larger numbers of HF patients are found to have detectable cTn with a persistent relationship between magnitude and outcome. This knowledge improves our ability to understand the mechanism of worsening HF, improve risk stratification, and detect potential injury related to new therapeutics in HF. As investigators begin to understand the relationship of detectable cTn to HF outcomes, as well as temporal changes in its magnitude, and its relationship to other circulating biomarkers, more insight may be gained into the progressive nature of cardiac dysfunction and the transition from chronic compensated to acute decompensated HF. Ultimately, this information might allow physicians to guide therapy, choose appropriate therapeutics, and improve HF outcomes.