Rapid Rule-Out of Myocardial Infarction After 30 Minutes as an Alternative to 1 Hour: The RACING-MI Cohort Study.

STUDY OBJECTIVE: The aim of this study was to investigate whether myocardial infarction can be safely ruled in or out after 30 minutes as an alternative to 1 hour. METHODS: This was a prospective, single-center clinical study enrolling patients admitted to the emergency department. Patients with chest pain suggestive of myocardial infarction were eligible for inclusion. There was no walk-in to the emergency department, and patients with highly elevated out-of-hospital troponin were transferred directly to an invasive heart center. High-sensitivity troponin I was measured at admission (0 hour), 30 minutes, 1 hour, and 3 hours. Diagnostic performance was assessed using the sensitivity and negative predictive value (primary endpoints) as measures of ability to rule out myocardial infarction. Specificity and positive predictive value of myocardial infarction were used as measures for the ability to rule in myocardial infarction (secondary endpoints). RESULTS: In total, 1,003 patients qualified for analysis. Median age was 64 (interquartile range 52 to 74) years, and 42% were women. Myocardial infarction was confirmed in 9% of patients. In the validation cohort (n=503), the 0-h/30-min algorithm assigned 242 (48%) patients to rule out, 54 (11%) to rule in, and 207 (41%) to the observational zone. This resulted in a sensitivity of 100% (92.0% to 100%), negative predictive value of 100% (95% confidence interval 98.5% to 100%), specificity of 96.7% (94.7% to 98.2%), and positive predictive value of 72.2% (58.4% to 83.5%). In comparison, the 0-h/1-h algorithm performed with a sensitivity of 100% (92.0% to 100%), negative predictive value of 100% (98.5% to 100%), specificity of 97.2% (95.2% to 98.5%), and positive predictive value of 75.5% (61.7% to 86.2%). CONCLUSION: The accelerated 0-h/30-min algorithm allowed for safe rule-out of myocardial infarction 30 minutes after admission. The rule-in ability of the 0-h/30-min algorithm was comparable to that of the 0-h/1h algorithm.

Clinical performance and exercise hemodynamics in patients with severe secondary tricuspid regurgitation and chronic atrial fibrillation.

OBJECTIVE: The study aimed to investigate the functional capacity and hemodynamics at rest and during exercise in patients with chronic atrial fibrillation and severe functional symptomatic tricuspid regurgitation (AF-FTR). BACKGROUND: Symptoms and clinical performance of severe AF-FTR mimic the population of patients with heart failure with preserved ejection fraction (HFpEF). Severe AF-FTR is known to be associated with an adverse prognosis whereas less is reported about the clinical performance including exercise capacity and hemodynamics in patients symptomatic AF-FTR. METHODS: Right heart catheterization (RHC) at rest and during exercise was conducted in a group of patients with stable chronic AF-TR and compared with a group of patients with HFpEF diagnosed with cardiac amyloid cardiomyopathy (CA). All patients had preserved ejection fraction and no significant left-sided disease. RESULTS: Patients with AF-FTR demonstrated a low exercise capacity that was comparable to CA patients (TR 4.9 ± 1.2 METS vs. CA 4. 7 ± 1.5 METS; P = 0.78) with an average peak maximal oxygen consumption of 15 mL/min/kg. Right atrium pressure increased significantly more in the AF-FTR patients as compared to CA patients at peak exercise (25 ± 8 vs 19 ± 9, p < 0.01) whereas PCWP increased significantly to a similar extent in both groups (31 ± 4 vs 31 ± 8 mmHg, p = 0.88). Cardiac output (CO) was significantly lower among AF-FTR at rest as compared to CA patients (3.6 ± 0.9 vs 4.4 ± 1.3 l/min; p < 0.05) whereas both groups demonstrated a poor but comparable CO reserve at peak exercise (7.3 ± 2.9 vs 7.9 ± 3.8 l/min, p = 0.59). CONCLUSIONS: AF-FTR contributes to the development of advanced heart failure symptoms and poor exercise capacity reflected in increased atrial filling pressures, reduced cardiac output at rest and during exercise sharing common features seen in HFpEF patients with other etiologies.

A systematic approach to weaning from extracorporeal membrane oxygenation in patients with refractory cardiac failure.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is commonly used to provide haemodynamic support for patients with severe cardiac failure. However, timing ECMO weaning remains challenging. We aimed to examine if an integrative weaning approach based on predefined haemodynamic, respiratory and echocardiographic criteria is associated with successful weaning. METHODS: All patients weaned from ECMO between April 2017 and April 2019 at Aarhus University Hospital, Denmark, were consecutively enrolled. Predefined haemodynamic, respiratory and echocardiographic criteria were assessed before and during ECMO flow reduction. A weaning attempt was commenced in haemodynamic stable patients and patients remaining stable at minimal flow were weaned from ECMO. Comparisons were made between patients who met the criteria for weaning at first attempt and patients who did not meet these criteria. Patients completing a full weaning attempt with no further need for mechanical support within 24 h were defined as successfully weaned. RESULTS: A total of 38 patients were included in the study, of whom 26 (68%) patients met the criteria for weaning. Among these patients, 25 (96%) could be successfully weaned. Successfully weaned patients were younger and had less need for inotropic support and ECMO duration was shorter. Fulfilling the weaning criteria was associated with successful weaning and both favourable 30-d survival and survival to discharge. CONCLUSION: An integrative weaning approach based on haemodynamic, respiratory and echocardiographic criteria may strengthen the clinical decision process in predicting successful weaning in patients receiving ECMO for refractory cardiac failure.

Point-of-care ultrasound findings in unselected patients in an emergency department -results from a prospective observational trial.

BACKGROUND: Point-of-care ultrasound (POCUS) can improve patient management in the emergency department (ED). However, previous studies have focused only on selected groups of patients, such as trauma, shock, dyspnea, or critically ill patients, or patients with an already known diagnosis. Most patients seen in the ED do not match these criteria. We aim to present total prevalence of positive findings when basic POCUS is applied to the broad population of patients seen in an emergency department. METHODS: We conducted a single-center prospective explorative observational study of 405 unselected patients aged 18 years or over. A structured whole-body ultrasound examination was performed on all patients within 2 h of arrival to the ED. The ultrasound examination consisted of focused cardiac ultrasound, focused abdominal ultrasound, focused assessment with sonography for trauma (FAST), and focused lung ultrasound. RESULTS: We managed to perform 94.5% of all planned examinations. The study revealed positive findings in 39.3% of all included patients. This study presents the prevalence of positive findings among subgroups of patients. Divided among the categories of chief complaint, we found 62 positive examinations in 58 (14.3%; 95% CI, 10.9-17.7) unique patients with orthopedic complaints, 77 positive examinations among 59 (14.6%; 95% CI, 11.1-18.0) unique patients with medical complaints, and 55 positive examinations among 42 (10.4%; 95% CI, 7.4-13.3) unique patients with abdominal surgical complaints. CONCLUSION: POCUS revealed positive findings in more than one third of unselected patients in the emergency department. The study presents the findings and distribution among categories of chief complaints. Future investigations are necessary to elucidate the implication of the findings.

Inotropic therapy for right ventricular failure in newborn piglets: effect on contractility, hemodynamics, and interventricular interaction.

OBJECTIVES: To investigate the effect of right ventricular stunning on interventricular relationships in newborn piglets and to determine the effect of three commonly used inotropic treatment strategies. DESIGN: Randomized, placebo-controlled animal study. SETTING: Aarhus University Hospital, animal laboratory. SUBJECTS: Twenty-eight newborn (4-d old) farm-bred piglets. INTERVENTIONS: Acute right ventricular failure was induced by 10 cycles of alternating 3 minutes of ischemia and reperfusion of the right coronary artery. After right ventricular failure was induced, treatment with epinephrine + milrinone, dopamine + milrinone, dobutamine, or control (saline) was initiated, and the animals were observed for 180 minutes. MEASUREMENTS AND MAIN RESULTS: Right and left ventricular systolic and diastolic variables were measured using pressure-volume loops recorded by conductance catheters. Arterial and central venous pressures were recorded, and cardiac index was determined by placing a flow probe around the pulmonary artery. Whole-body perfusion was evaluated by measuring pH and lactate in arterial blood samples. Induction of right ventricular stunning resulted in decreased ejection fraction (51% ± 4% vs 40% ± 12%, p = 0.0004); caused an interventricular septum deviation, decreased mean arterial pressure (49 ± 10 mm Hg vs 43 ± 11 mm Hg, p = 0.03), and increased blood lactate (1.85 ± 0.6 mM vs 5.79 ± 3.16 mM, p < 0.00001); and led to a decrease in blood pH (7.37 ± 0.08 vs 7.23 ± 0.13, p < 0.00001). A mortality rate greater than 50% was observed in the control group. All inotropic interventions increased contractility significantly in both the left and right ventricle. The effect of dobutamine on right ventricular failure decreased after 30 minutes and was indistinguishable from the control group after 3 hours. Dobutamine-treated animals had lower perfusion pressures and blood pH compared with epinephrine + milrinone and dopamine + milrinone groups. CONCLUSIONS: In newborn piglets, dobutamine had a nonsustained effect on right ventricular failure, resulting in decreased contractility and impaired perfusion compared with both dopamine and epinephrine administered in combination with milrinone.

Drainage of large pleural effusions increases left ventricular preload.

OBJECTIVES: The aim of the study was to investigate if pleurocentesis in patients with pleural effusion would lead to changes in systolic and diastolic function of the left ventricle. DESIGN: The study was descriptive, and patients were their own controls. SETTING: The setting was a single-center university hospital. PARTICIPANTS: Patients with pleural effusion requiring pleurocentesis were eligible for inclusion. INTERVENTIONS: The participants who had pleurocentesis performed were available for analysis. MEASUREMENTS AND MAIN RESULTS: Prior to pleurocentesis and approximately 1 hour after, patients were examined primarily with transthoracic echocardiography. The examination included measurements of left ventricular volumes and measures of diastolic function assessed by Doppler echocardiography. Thirty-five patients were included, and 11 later were excluded, yielding a study population of 24. Preload, expressed as left ventricular end-diastolic volume, increased significantly from before to after pleurocentesis (p=0.014). None of the diastolic parameters showed significant results. Significant changes were observed for heart rate, supplementary O2, respiratory frequency, and saturation. CONCLUSIONS: Pleurocentesis increased left ventricular preload and improved respiratory function.

Ultrasound of the inferior vena cava does not predict hemodynamic response to early hemorrhage.

BACKGROUND: Ultrasonographic evaluation of the inferior vena cava (IVC) provides information on central hemodynamics and predicts fluid responsiveness during positive pressure ventilation. In spontaneously breathing patients, the correlations between IVC dynamics and the hemodynamic response to volume shifts remain to be described. OBJECTIVES: We aimed to describe the correlation between IVC dynamics and the changes in cardiac output (CO) caused by controlled hemorrhage. METHODS: Healthy donors from the blood bank were eligible for inclusion. Measurements of the IVC and CO were performed before and immediately after blood donation using ultrasound methods. A control group served to evaluate the effect of resting. RESULTS: Thirty-seven participants completed the study. IVC collapsibility index (IVC-CI) and IVC end expiratory diameter (IVCe) both changed significantly after blood donation (p < 0.001). The baseline IVC-CI and IVCe did not correlate with the change in CO (p-values ≥ 0.40). The alterations in IVC-CI and IVCe induced by blood donation also did not correlate with the change in CO (p ≥ 0.71). The sensitivities of IVC-CI or IVCe, defined as an increase in IVC-CI and a decrease in IVCe, for picking up any decrease in CO were 81.3% and 84.4%, respectively. In the control group, no effect was seen between measurements. CONCLUSION: IVC-CI and IVCe did not correlate with the magnitude of hemodynamic response to early hemorrhage. The sensitivity of serial IVC measurements was approximately 80% for detecting early blood loss.

Evaluation of cardiovascular biomarkers in HIV-infected patients switching to abacavir or tenofovir based therapy.

BACKGROUND: Our objective was to evaluate and compare the effect of abacavir on levels of biomarkers associated with cardiovascular risk. METHODS: In an open-label randomized trial, HIV-infected patients were randomized 1:1 to switch from zidovudine/lamivudine to abacavir/lamivudine or tenofovir/emtricitabine. In the present analysis, we measured levels of interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular adhesion molecule-1 (sVCAM-1), E-selectin, and myeloperoxidase (MPO) at baseline and 4, 12, and 48 weeks after randomization. D-dimer and fasting lipids were measured at baseline and weeks 12 and 48. Levels of biomarkers at all time points and changes from baseline were compared across study arms using Wilcoxon rank sum test. RESULTS: Of 40 included patients, 35 completed 48 weeks of randomized therapy and follow up. Levels of E-selectin (P=0.004) and sVCAM-1 (P=0.041) increased transiently from baseline to week 4 in the abacavir arm compared with the tenofovir arm, but no long-term increases were detected. We found no significant differences between study arms in the levels or changes in the levels of sICAM-1, MPO, d-dimer, IL-6, or hs-CRP. Levels of total cholesterol and high density lipoprotein (HDL) increased in the abacavir arm relative to the tenofovir arm, but no difference was found in total cholesterol/HDL ratio. CONCLUSION: In patients randomized to abacavir-based HIV-treatment transient increases were seen in the plasma levels of E-selectin and sVCAM-1 compared with treatment with tenofovir, but no difference between study arms was found in other biomarkers associated with endothelial dysfunction, inflammation, or coagulation. The clinical significance of these findings is uncertain. TRIAL REGESTRATION: Clinicaltrials.gov identifier: NCT00647244.

Point-of-care ultrasound induced changes in management of unselected patients in the emergency department - a prospective single-blinded observational trial.

BACKGROUND: Point-of-Care ultrasound (POCUS) changes the management in specific groups of patients in the Emergency Department (ED). It seems intuitive that POCUS holds an unexploited potential on a wide variety of patients. However, little is known about the effect of ultrasound on the broad spectrum of unselected patients in the ED. This study aimed to identify the effect on the clinical management if POCUS was applied on unselected patients. Secondarily the study aimed to identify predictors of ultrasound changing management. METHODS: This study was a blinded observational single center trial. A basic whole body POCUS protocol was performed in extension to the physical examination. The blinded treating physicians were interviewed about the presumptive diagnosis and plan for the patient. Subsequently the physicians were unblinded to the POCUS results and asked to choose between five options regarding the benefit from POCUS results. RESULTS: A total of 403 patients were enrolled in this study. The treating physicians regarded POCUS examinations influence on the diagnostic workup or treatment as following: 1) No new information: 249 (61.8%), 2) No further action: 45 (11.2%), 3) Further diagnostic workup needed: 52 (12.9%), 4) Presumptive diagnosis confirmed 38 (9.4%), and 5) Immediate treatment needed: 19 (4.7%). Predictors of beneficial ultrasound were: (a) triage > 1, (b) patient comorbidities (cardiac disease, hypertension or lung disease), or (c) patients presenting with abdominal pain, dyspnea, or syncope. CONCLUSION: POCUS was found to be potentially beneficial in 27.0% of all patients. High triage score, known cardiac disease, hypertension, pulmonary diseases, a clinical presentation with abdominal pain, dyspnea, or syncope are predictors of this. Future research should focus on patient-important outcomes when applying POCUS on these patients. TRIAL REGISTRATION: The trail was registered prior to patient inclusion with the Danish Data Protection Agency (https://www.datatilsynet.dk/ Case no: 1-16-02-603-14) and Clinical Trials (www.clinicaltrials.gov/ Protocol ID: DNVK1305018).

Learning Curves for Training in Ultrasonography-Based Examination of Umbilical Catheter Placement: A Piglet Study.

BACKGROUND: The training required for accurate assessment of umbilical catheter placement by ultrasonography (US) is unknown. OBJECTIVE: To describe the learning curve and provide an estimate of the accuracy of physicians' US examinations (US skills) and self-confidence when examining umbilical catheter tip placement. METHODS: Twenty-one physicians with minimal experience in US completed a 1.5-hour eLearning module. Ten piglets with catheters inserted in the umbilical vessels were used as training objects. Following eLearning each physician performed up to twelve 10-min US examinations of the piglets. Expert examinations were reference standards. Sensitivity and specificity of physicians' skills in detecting catheter tip placement by US was used to describe the learning curve. Self-confidence was reported by Likert scale after each examination. RESULTS: Physicians' detection of a correctly placed and misplaced umbilical artery catheter tip increased by an odds ratio of 1.6 (95% CI: 1.1, 2.3) and 3.6 (95% CI: 1.7, 7.8) per examination performed. A sensitivity of 0.97 (95% CI: 0.80, 0.99) and specificity of 0.95 (95% CI: 0.84, 0.99) was reached after 6 examinations. For the venous catheter, US skills in detecting a misplaced catheter tip increased with an odds ratio of 2.4 (95% CI: 1.2, 4.8) per US examination. Overall, performance and self-confidence plateaus were reached after 6 examinations. CONCLUSION: We found steep learning curves for targeted US examination of umbilical catheter placement. eLearning followed by 6 examinations was found to be adequate training to perform with a sufficiently high accuracy and self-confidence to allow for point-of-care use.

Timing of focused cardiac ultrasound during advanced life support - A prospective clinical study.

INTRODUCTION: Focused cardiac ultrasound can potentially identify reversible causes of cardiac arrest during advanced life support (ALS), but data on the timing of image acquisition are lacking. This study aimed to compare the quality of images obtained during rhythm analysis, bag-mask ventilations, and chest compressions. METHODS: Adult patients in cardiac arrest were prospectively included during 23 months at a Danish community hospital. Physicians who had completed basic ultrasound training performed subcostal focused cardiac ultrasound during rhythm analysis, bag-mask ventilations, and chest compressions. Image quality was categorised as either useful for interpretation or not. Two echocardiography experts rated images useful for interpretation if all the following characteristics could be determined: 1) right ventricle larger than left ventricle, 2) pericardial fluid, and 3) collapsing ventricles. RESULTS: Images were obtained from 60 of 114 patients undergoing ALS. A higher proportion of the images obtained during rhythm analysis and bag-mask ventilations were useful for interpretation when compared with chest compressions (rhythm analysis vs chest compressions: OR 2.2 (95%CI 1.3-3.8), P = 0.005; bag mask ventilations vs chest compressions: OR 2.0 (95%CI 1.1-3.7), P = 0.03). There was no difference between images obtained during rhythm analysis and bag-mask ventilations (OR 1.1 (95%CI 0.6-2.0), P = 0.74). CONCLUSION: The quality of focused cardiac ultrasound images obtained during rhythm analysis and bag-mask ventilations was superior to that of images obtained during chest compressions. There was no difference in the quality of images obtained during rhythm analysis and bag-mask ventilations. Bag-mask ventilations may constitute an overlooked opportunity for image acquisition during ALS.

Trauma facilities in Denmark - a nationwide cross-sectional benchmark study of facilities and trauma care organisation.

BACKGROUND: Trauma is a leading cause of death among adults aged < 44 years, and optimal care is a challenge. Evidence supports the centralization of trauma facilities and the use multidisciplinary trauma teams. Because knowledge is sparse on the existing distribution of trauma facilities and the organisation of trauma care in Denmark, the aim of this study was to identify all Danish facilities that care for traumatized patients and to investigate the diversity in organization of trauma management. METHODS: We conducted a systematic observational cross-sectional study. First, all hospitals in Denmark were identified via online services and clarifying phone calls to each facility. Second, all trauma care manuals on all facilities that receive traumatized patients were gathered. Third, anesthesiologists and orthopedic surgeons on call at all trauma facilities were contacted via telephone for structured interviews. RESULTS: A total of 22 facilities in Denmark were found to receive traumatized patients. All facilities used a trauma care manual and all had a multidisciplinary trauma team. The study found three different trauma team activation criteria and nine different compositions of teams who participate in trauma care. Training was heterogeneous and, beyond the major trauma centers, databases were only maintained in a few facilities. CONCLUSION: The study established an inventory of the existing Danish facilities that receive traumatized patients. The trauma team activation criteria and the trauma teams were heterogeneous in both size and composition. A national database for traumatized patients, research on nationwide trauma team activation criteria, and team composition guidelines are all called for.

Ultrasonography in trauma: a nation-wide cross-sectional investigation.

BACKGROUND: The Focused Assessment with Sonography in Trauma (FAST) protocol is considered beneficial in emergent evaluation of trauma patients with blunt or penetrating injury and has become integrated into the Advanced Trauma Life Support (ATLS) protocol. No guidelines exist as to the use of ultrasonography in trauma in Denmark. We aimed to determine the current use of ultrasonography for assessing trauma patients in Denmark. METHODS: We conducted a nation-wide cross-sectional investigation of ultrasonography usage in trauma care. The first phase consisted of an Internet-based investigation of existing guidelines, and the second phase was a series of structured interviews of orthopedic surgeons, anesthesiologists, and radiologists on call in all hospitals receiving traumatized patients in Denmark. RESULTS: Guidelines were obtained from all 22 hospitals receiving traumatized patients in Denmark. Twenty-one (95.5%) of the guidelines included and recommended FAST as part of trauma assessment. The recommended person to perform the examination was the radiologist in n = 11 (50.0%), the surgeon in n = 6 (27.3%), the anesthesiologist in n = 1 (4.5%), and unspecified in n = 3 (13.6%) facilities. FAST indications varied between circulatory instability n = 8 (36.4%), team leader's discretion n = 6 (27.3%), abdominal trauma n = 3 (13.6%), and not specified n = 6 (27.3%). Telephone interviews revealed that exams were always n = 8 (36.4%) or often n = 4 (18.2%) registered in the patients' charts. The remaining n = 10 (45.5%) facilities either never registered n = 2 (9.1%), it was not possible to register n = 1 (4.5%), or unknown by the trauma leaders n = 7 (31.8%). Images were often stored in n = 1 (4.5%), never stored in n = 10 (45.5%), not possible to store in n = 2 (9.1%), and unknown in n = 9 (40.9%) facilities. CONCLUSION: Ultrasonography was used in a non-uniform fashion by multiple specialties in Danish trauma facilities. Very few images from FAST examinations were stored and documentation was scanty. National guidelines on application and documentation of ultrasonography in trauma are called for.