Clinical Influence of Handheld Ultrasound, Supported by Automatic Quantification and Telemedicine, in Suspected Heart Failure.

Early and correct heart failure (HF) diagnosis is essential to improvement of patient care. We aimed to evaluate the clinical influence of handheld ultrasound device (HUD) examinations by general practitioners (GPs) in patients with suspected HF with or without the use of automatic measurement of left ventricular (LV) ejection fraction (autoEF), mitral annular plane systolic excursion (autoMAPSE) and telemedical support. Five GPs with limited ultrasound experience examined 166 patients with suspected HF (median interquartile range = 70 (63-78) y; mean ± SD EF = 53 ± 10%). They first performed a clinical examination. Second, they added an examination with HUD, automatic quantification tools and, finally, telemedical support by an external cardiologist. At all stages, the GPs considered whether the patients had HF. The final diagnosis was made by one of five cardiologists using medical history and clinical evaluation including a standard echocardiography. Compared with the cardiologists' decision, the GPs correctly classified 54% by clinical evaluation. The proportion increased to 71% after adding HUDs, and to 74 % after telemedical evaluation. Net reclassification improvement was highest for HUD with telemedicine. There was no significant benefit of the automatic tools (p ≥ 0.58). Addition of HUD and telemedicine improved the GPs' diagnostic precision in suspected HF. Automatic LV quantification added no benefit. Refined algorithms and more training may be needed before inexperienced users benefit from automatic quantification of cardiac function by HUDs.

Real-time automatic quantification of left ventricular function by hand-held ultrasound devices in patients with suspected heart failure: a feasibility study of a diagnostic test with data from general practitioners, nurses and cardiologists.

OBJECTIVES: To evaluate the feasibility and reliability of hand-held ultrasound (HUD) examinations with real-time automatic decision-making software for ejection fraction (autoEF) and mitral annular plane systolic excursion (autoMAPSE) by novices (general practitioners), intermediate users (registered cardiac nurses) and expert users (cardiologists), respectively, compared to reference echocardiography by cardiologists in an outpatient cohort with suspected heart failure (HF). DESIGN: Feasibility study of a diagnostic test. SETTING AND PARTICIPANTS: 166 patients with suspected HF underwent HUD examinations with autoEF and autoMAPSE measurements by five novices, three intermediate-skilled users and five experts. HUD results were compared with a reference echocardiography by experts. A blinded cardiologist scored all HUD recordings with automatic measurements as (1) discard, (2) accept, but adjust the measurement or (3) accept the measurement as it is. PRIMARY OUTCOME MEASURE: The feasibility of automatic decision-making software for quantification of left ventricular function. RESULTS: The users were able to run autoEF and autoMAPSE in most patients. The feasibility for obtaining accepted images (score of ≥2) with automatic measurements ranged from 50% to 91%. The feasibility was lowest for novices and highest for experts for both autoEF and autoMAPSE (p≤0.001). Large coefficients of variation and wide coefficients of repeatability indicate moderate agreement. The corresponding intraclass correlations (ICC) were moderate to good (ICC 0.51-0.85) for intra-rater and poor (ICC 0.35-0.51) for inter-rater analyses. The findings of modest to poor agreement and reliability were not explained by the experience of the users alone. CONCLUSION: Novices, intermediate and expert users were able to record four-chamber views for automatic assessment of autoEF and autoMAPSE using HUD devices. The modest feasibility, agreement and reliability suggest this should not be implemented into clinical practice without further refinement and clinical evaluation. TRIAL REGISTRATION NUMBER: NCT03547076.

Measurement of high-sensitivity troponin-I in suspected coronary-related chest pain in Emergency Departments. / Høysensitiv troponin I-måling ved koronarsuspekte brystsmerter i akuttmottak.

BACKGROUND: The study aimed to evaluate a new algorithm based on analyses of high-sensitivity troponin I for rapid diagnostic clarification in cases of suspected cardiac chest pain. MATERIAL AND METHOD: Two time periods - before (01.10.2016-31.12.2016) and after (01.03.2017-28.02.2018) the introduction of a diagnostic algorithm - were studied by reviewing the medical records of patients who arrived at the emergency department with chest pain. The diagnostic algorithm included a high-sensitivity troponin I test on admission (0 hours) and one hour later (the 0 h/1 h algorithm). The primary endpoint was the proportion of patients that were discharged directly from the emergency department. Secondary endpoints were acute cardiac arrest and death within 30 days and within one year. RESULTS: A larger proportion of patients with chest pain were discharged directly from the emergency department when the 0 h/1 h algorithm was used (10/91 (11 %) before versus 118/306 (39 %) after, p <0.001). Deaths and the incidence of acute myocardial infarction one year after the introduction of the 0 h/1 h algorithm were low (≤ 3 %) and not statistically different from the period before the introduction (p≥ 0.20). INTERPRETATION: The implementation of a diagnostic algorithm based on measurements of high-sensitivity troponin I resulted in fewer patients being hospitalised, and we did not register more deaths or deaths from myocardial infarction. The algorithm was suitable for identifying patients with chest pain who could safely be discharged without the need for hospitalisation, which we believe may optimise patient flow in hospitals.

Feasibility and Accuracy of Tele-Echocardiography, With Examinations by Nurses and Interpretation by an Expert via Telemedicine, in an Outpatient Heart Failure Clinic.

OBJECTIVES: To study the feasibility and accuracy of focused echocardiography by nurses supported by near-real-time interpretation via telemedicine by an experienced cardiologist. METHODS: Fifty consecutive patients were included from an outpatient heart failure (HF) clinic. Limited echocardiography was performed by 1 of 3 specialized nurses. The echocardiograms were transferred by a secure transfer model for near-real-time interpretation to 1 out-of-hospital cardiologist, assessing, among others, the left ventricular (LV) internal diameter, end-diastolic volume, ejection fraction, left atrial (LA) indexed end-systolic volume, mitral early inflow velocity (E), the ratio of E to mitral late inflow, and the ratio of E to the mitral annular early diastolic velocity. The reference method was echocardiography by 1 of 4 experienced cardiologists. RESULTS: The median age of the population (46% women) was 79 (range, 33-95) years. The assessment and quantification of LA and LV dimensions, volumes, and functional indices were feasible in 94% or more via the telemedical approach. The agreement with reference measurements was very high by the telemedical approach. The mean duration ± SD of the complete telemedical approach from the start of echocardiography until the cardiologist's report was received by the caregiving nurse was 1.32 ± 0.36 (range, 1.58) hours. The correlations with reference to the above-specified indices were r = 0.75 to 0.94. CONCLUSIONS: Limited echocardiography by nurses in an outpatient heart failure clinic, supported by interpretation by an out-of-hospital cardiologist, was feasible and reliable. This may reduce geographic disparities and allow more patients to benefit from the advantages of implementing focused echocardiography by noncardiologists in diagnostics and follow-up.

Feasibility and Diagnostic Accuracy of Point-of-Care Abdominal Sonography by Pocket-Sized Imaging Devices, Performed by Medical Residents.

OBJECTIVES: We aimed to study the feasibility and diagnostic performance of bedside ultrasound by examination of the liver, gallbladder, kidneys, and abdominal aorta performed by medical residents with limited experience in ultrasound, on emergency admissions using pocket-sized imaging devices (PSIDs). METHODS: A total of 199 patients admitted acutely to the medical department at the non-university Levanger Hospital, Norway, during the period from April 4 to June 23, 2011, were consecutively included. Six medical residents, selected by drawing, examined these patients with a PSID at admission. Reference imaging was performed and/or judged at the Department of Radiology. RESULTS: Each resident performed a median of 28 examinations (interquartile range 24-46). Imaging of the kidneys and liver were feasible in 85 and 82% of the cases, and the corresponding values for the gallbladder and abdominal aorta were 79 and 50%, respectively. The sensitivity of medical residents to detect organ pathology with the aid of PSID, ranged between 54% (95% confidence interval [CI]: 29-77%) and 74% (95% CI: 51-88%). Assessment of the aortic dimension showed moderate correlation, with r = 0.38. CONCLUSIONS: Examination by PSID by inexperienced residents may allow for early detection of abdominal pathology, but do not appear to be accurate enough to rule out pathology in the abdominal organs.

Active Exploration for Learning Symbolic Representations.

We introduce an online active exploration algorithm for data-efficiently learning an abstract symbolic model of an environment. Our algorithm is divided into two parts: the first part quickly generates an intermediate Bayesian symbolic model from the data that the agent has collected so far, which the agent can then use along with the second part to guide its future exploration towards regions of the state space that the model is uncertain about. We show that our algorithm outperforms random and greedy exploration policies on two different computer game domains. The first domain is an Asteroids-inspired game with complex dynamics but basic logical structure. The second is the Treasure Game, with simpler dynamics but more complex logical structure.

Diagnostic influence of routine point-of-care pocket-size ultrasound examinations performed by medical residents.

OBJECTIVES: We aimed to investigate the potential benefit of adding goal-directed ultrasound examinations performed by on-call medical residents using a pocket-size imaging device in patients admitted to a medical department. METHODS: A total of 992 emergency admissions to the medical department at a nonuniversity hospital in Norway were included. Patients admitted on dates with an on-call medical resident randomized to use a pocket-size imaging device were eligible for pocket-size cardiac and abdominal ultrasound examinations or standard care. The cardiac examination included estimation of right and left ventricular sizes and global systolic function and regional left ventricular systolic function, evaluation for pleural and pericardial effusion, and valvular disease. The abdominal examination looked for signs of gross abnormalities of the liver, gallbladder, abdominal aorta, inferior vena cava, and urinary system. Six of 12 medical residents with limited ultrasound experience were randomized to perform the examinations. Diagnostic corrections were made, and findings were confirmed by reference standard diagnostics. RESULTS: A total of 199 patients were examined. Median times used were 5.7 minutes for the cardiac examination and 4.7 minutes for the abdominal examination. In 13 patients (6.5%), the examination resulted in a major change in the primary diagnosis. In 21 patients (10.5%), the diagnosis was verified, and in 48 (24.0%), an additional important diagnosis was made. CONCLUSIONS: By implementing pocket-size ultrasound examinations that took less than 11 minutes to the usual care, we corrected, verified, or added important diagnoses in more than 1 of 3 emergency medical admissions. Point-of-care examinations with a pocket-size imaging device increased medical residents' diagnostic accuracy and capability.

Feasibility and accuracy of point-of-care pocket-size ultrasonography performed by medical students.

BACKGROUND: Point-of-care ultrasound performed by clinicians is a useful supplement in the treatment and assessment of patients. We aimed to investigate whether medical students with minimal training were able to successfully acquire and interpret ultrasound images using a pocket-size imaging device (PSID) as a supplement to their clinical practice. METHODS: Thirty 5th year (of six) medical students volunteered to participate. They were each given a personal PSID device to use as a supplement to their physical examination during their allocated hospital terms. Prior to clinical placement the students were given three evenings of hands-on training with PSID by a board certified radiologist/cardiologist, including three short lectures (<20 min). The students were shown basic ultrasound techniques and taught to assess for basic, clinically relevant pathology. They were specifically instructed to assess for the presence or absence of reduced left ventricular function (assessed as mitral annular excursion < 10 mm), pericardial effusion, pleural effusion, lung comets, hydronephrosis, bladder distension, gallstones, abdominal free-fluid, cholecystitis, and estimate the diameter of abdominal aorta and inferior vena cava. RESULTS: A total of 211 patients were examined creating 1151 ultrasound recordings. Acceptable organ presentation was 73.8% (95% CI 63.1-82.6) for cardiovascular and 88.4% (95% CI: 80.6-93.6) for radiological structures. Diagnostic accuracy was 93.5% (95% CI: 89.0-96.2) and 93.2% (95% CI: 87.4-96.5) respectively. CONCLUSION: Medical students with minimal training were able to use PSID as a supplement to standard physical examination and successfully acquire acceptable relevant organ recordings for presentation and correctly interpret these with great accuracy.

Feasibility and reliability of point-of-care pocket-size echocardiography performed by medical residents.

AIMS: To study the feasibility and reliability of pocket-size hand-held echocardiography (PHHE) by medical residents with limited experience in ultrasound. METHODS AND RESULTS: A total of 199 patients admitted to a non-university medical department were examined with PHHE. Six out of 14 medical residents were randomized to use a focused protocol and examine the heart, pericardium, pleural space, and abdominal large vessels. Diagnostic corrections were made and findings were confirmed by standard diagnostics. The median time consumption for the examination was 5.7 min. Each resident performed a median of 27 examinations. The left ventricle was assessed to satisfaction in 97% and the pericardium in all patients. The aortic and atrioventricular valves were assessed in at least 76% and the abdominal aorta in 50%, respectively. Global left-ventricular function, pleural, and pericardial effusion showed very strong correlation with reference method (Spearman's r ≥ 0.8). Quantification of aortic stenosis and regurgitation showed strong correlation with r = 0.7. Regurgitations in the atrioventricular valves showed moderate correlations, r = 0.5 and r = 0.6 for mitral and tricuspid regurgitation, respectively, similar to dilatation of the left atrium (r = 0.6) and detection of regional dysfunction (r = 0.6). Quantification of the abdominal aorta (aneurysmatic or not) showed strong correlation, r = 0.7, while the inferior vena cava diameter correlated moderately, r = 0.5. CONCLUSION: By adding a PHHE examination to standard care, medical residents were able to obtain reliable information of important cardiovascular structures in patients admitted to a medical department. Thus, focused examinations with PHHE performed by residents after a training period have the potential to improve in-hospital diagnostic procedures.

Feasibility and reliability of point-of-care pocket-sized echocardiography.

AIMS: To study the reliability and feasibility of point-of-care pocket-sized echocardiography (POCKET) at the bedside in patients admitted to a medical department at a non-university hospital. METHODS AND RESULTS: One hundred and eight patients were randomized to bedside POCKET examination shortly after admission and later high-end echocardiography (HIGH) in the echo-lab. The POCKET examinations were done by cardiologists on their ward rounds. Assessments of global and regional left ventricular (LV) function, right ventricular (RV) function, valvular function, left atrial (LA) size, the pericardium and pleura were done with respect to effusion and measurements of inferior vena cava (IVC) and abdominal aorta (AA) were performed. Correlations between POCKET and HIGH/appropriate radiological technique for LV function, AA size and presence of pericardial effusion were almost perfect, with r ≥ 0.92. Strong correlation (r ≥ 0.81) was shown for RV and valvular function, except for grading of aortic stenosis (r = 0.62). The correlations were substantial for IVC and LA dimensions. Median time used for bedside screening with POCKET was 4.2 min (range: 2.3-13.0). There was excellent feasibility for cardiac structures and pleura, which was assessed to satisfaction in ≥ 94% of patients. Lower feasibility (71-79%) was seen for the abdominal great vessels. CONCLUSION: Point-of-care semi-quantitative evaluation of cardiac anatomy and function showed high feasibility and correlation with the reference method for most indices. Pocket-sized echocardiographic examinations of ∼4 min length, performed at the bedside by experts, offers reliable assessment of cardiac structures, the pleural space and the large abdominal vessels. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov; unique ID: NCT01081210.