A visual approach for the accurate determination of echocardiographic left ventricular ejection fraction by medical students

Association of echocardiographic parameters with all-cause and cardiovascular mortality in patients with type 2 diabetes

BACKGROUND

This study aimed to evaluate associations between echocardiography markers and mortality in patients with type 2 diabetes mellitus (T2DM).

METHODS

Diabetes Care Management Program database of a medical center was used, including 5612 patients with T2DM aged 30 years and older and who underwent echocardiography assessment between 2001 and 2021. Cox proportional hazard regression models were used to evaluate associations of echocardiography abnormalities with all-cause and expanded cardiovascular disease (CVD) mortality.

RESULTS

During a mean follow-up of 5.8 years, 1273 patients died. Hazard ratios (95% confidence intervals) of all-cause mortality for each standard deviation increase were presented for the cardiac systolic function indicator of left ventricular ejection fraction (0.77, 0.73-0.81), cardiac structural parameters of left ventricular mass index (1.25, 1.19-1.31) and left atrial volume index (1.31, 1.25-1.37), and cardiac diastolic function of E/A ratio (1.10, 1.07-1.13), E/e' ratio (1.37, 1.30-1.45), and TR velocity (1.25, 1.18-1.32); meanwhile, the values of expanded CVD mortality included left ventricular ejection fraction (0.67, 0.62-0.72), left ventricular mass index (1.35, 1.25-1.45), left atrial volume index (1.40, 1.31-1.50), E/A ratio (1.12, 1.08-1.16), E/e' ratio (1.57, 1.46-1.69), and TR velocity (1.29, 1.19-1.39), respectively.

CONCLUSIONS

Cardiac systolic function indicator of left ventricular ejection fraction, cardiac structural parameters of left ventricular mass index and left atrial volume index, and cardiac diastolic function indicators of E/A ratio, E/e' ratio, and TR velocity are associated with all-cause and expanded CVD mortality in patients with T2DM.

Artificial Intelligence-Based Left Ventricular Ejection Fraction by Medical Students for Mortality and Readmission Prediction

INTRODUCTION

Point-of-care ultrasound has become a universal practice, employed by physicians across various disciplines, contributing to diagnostic processes and decision-making.

AIM

To assess the association of reduced (<50%) left-ventricular ejection fraction (LVEF) based on prospective point-of-care ultrasound operated by medical students using an artificial intelligence (AI) tool and 1-year primary composite outcome, including mortality and readmission for cardiovascular-related causes.

METHODS

Eight trained medical students used a hand-held ultrasound device (HUD) equipped with an AI-based tool for automatic evaluation of the LVEF of non-selected patients hospitalized in a cardiology department from March 2019 through March 2020.

RESULTS

The study included 82 patients (72 males aged 58.5 ± 16.8 years), of whom 34 (41.5%) were diagnosed with AI-based reduced LVEF. The rates of the composite outcome were higher among patients with reduced systolic function compared to those with preserved LVEF (41.2% vs. 16.7%, p = 0.014). Adjusting for pertinent variables, reduced LVEF independently predicted the composite outcome (HR 2.717, 95% CI 1.083-6.817, p = 0.033). As compared to those with LVEF ≥ 50%, patients with reduced LVEF had a longer length of stay and higher rates of the secondary composite outcome, including in-hospital death, advanced ventilatory support, shock, and acute decompensated heart failure.

CONCLUSION

AI-based assessment of reduced systolic function in the hands of medical students, independently predicted 1-year mortality and cardiovascular-related readmission and was associated with unfavorable in-hospital outcomes. AI utilization by novice users may be an important tool for risk stratification for hospitalized patients.

Empowering Medical Students: Harnessing Artificial Intelligence for Precision Point-of-Care Echocardiography Assessment of Left Ventricular Ejection Fraction

Introduction

Point-of-care ultrasound (POCUS) use is now universal among nonexperts. Artificial intelligence (AI) is currently employed by nonexperts in various imaging modalities to assist in diagnosis and decision making.

Aim

To evaluate the diagnostic accuracy of POCUS, operated by medical students with the assistance of an AI-based tool for assessing the left ventricular ejection fraction (LVEF) of patients admitted to a cardiology department.

Methods

Eight students underwent a 6-hour didactic and hands-on training session. Participants used a hand-held ultrasound device (HUD) equipped with an AI-based tool for the automatic evaluation of LVEF. The clips were assessed for LVEF by three methods: visually by the students, by students + the AI-based tool, and by the cardiologists. All LVEF measurements were compared to formal echocardiography completed within 24 hours and were evaluated for LVEF using the Simpson method and eyeballing assessment by expert echocardiographers.

Results

The study included 88 patients (aged 58.3 ± 16.3 years). The AI-based tool measurement was unsuccessful in 6 cases. Comparing LVEF reported by students' visual evaluation and students + AI vs. cardiologists revealed a correlation of 0.51 and 0.83, respectively. Comparing these three evaluation methods with the echocardiographers revealed a moderate/substantial agreement for the students + AI and cardiologists but only a fair agreement for the students' visual evaluation.

Conclusion

Medical students' utilization of an AI-based tool with a HUD for LVEF assessment achieved a level of accuracy similar to that of cardiologists. Furthermore, the use of AI by the students achieved moderate to substantial inter-rater reliability with expert echocardiographers' evaluation.

Translating Guidelines into Practical Practice: Point-of-Care Ultrasound for Pediatric Critical Care Clinicians

Point-of-care ultrasound (POCUS) is now transitioning from an emerging technology to a standard of care for critically ill children. POCUS can provide immediate answers to clinical questions impacting management and outcomes within this fragile population. Recently published international guidelines specific to POCUS use in neonatal and pediatric critical care populations now complement previous Society of Critical Care Medicine guidelines. The authors review consensus statements within guidelines, identify important limitations to statements, and provide considerations for the successful implementation of POCUS in the pediatric critical care setting.

Comparison of visual estimation and quantitative measurement of left ventricular ejection fraction in untrained perioperative echocardiographers

BACKGROUND

Perioperative evaluation of the left ventricular systolic function is essential information to help diagnose and manage life-threatening perioperative emergencies. Although quantifying the left ventricular ejection fraction (LVEF) is recommended to determine the left ventricular function, it may not always be feasible in emergency perioperative settings. This study compared the visual estimation of LVEF (eyeballing) by noncardiac anesthesiologists with the quantitative LVEF measured using a modified Simpson's biplane method.

METHODS

Transesophageal echocardiographic (TEE) studies of 35 patients were selected and 3 different echocardiographic views (the mid-esophageal four chamber view, the mid-esophageal two chamber view, and the transgastric mid-papillary short axis view) were recovered from each study and displayed in random order. Two cardiac anesthesiologists certified in perioperative echocardiography independently measured LVEF using the modified Simpson method and categorized LVEF into five grades: hyperdynamic LVEF, normal, mildly reduced LVEF, moderately reduced LVEF and severely reduced LVEF. Seven noncardiac anesthesiologists with limited experience in echocardiography also reviewed the same TEE studies and estimated the LVEF and graded LV function. The precision of the LV function classification and the correlation between visual estimation of LVEF and quantitative LVEF were calculated. The agreement of measurements between the two methods was also assessed.

RESULTS

Pearson's correlation between the LVEF estimated by the participants and the quantitative LVEF using the modified Simpson method was 0.818 (p < 0.001). Of a total of 245 responses, 120 (49.0%) responses were correct grading of the LV function. Participants were able to classify the LV function more accurately in the LV function grades 1 and 5 (65.3%). The 95% level of agreement of the Bland-Altman method was - 11.3-24.5. -21.9-22.6, - 23.1-26.5, - 20.5-22.0 and - 26.6-11.1 for LV grade 1 to 5, respectively.

CONCLUSION

Visual estimation of LVEF in perioperative TEE has acceptable accuracy in untrained echocardiographers and can be used for rescue TEE.

International consensus conference recommendations on ultrasound education for undergraduate medical students

OBJECTIVES

The purpose of this study is to provide expert consensus recommendations to establish a global ultrasound curriculum for undergraduate medical students.

METHODS

64 multi-disciplinary ultrasound experts from 16 countries, 50 multi-disciplinary ultrasound consultants, and 21 medical students and residents contributed to these recommendations. A modified Delphi consensus method was used that included a systematic literature search, evaluation of the quality of literature by the GRADE system, and the RAND appropriateness method for panel judgment and consensus decisions. The process included four in-person international discussion sessions and two rounds of online voting.

RESULTS

A total of 332 consensus conference statements in four curricular domains were considered: (1) curricular scope (4 statements), (2) curricular rationale (10 statements), (3) curricular characteristics (14 statements), and (4) curricular content (304 statements). Of these 332 statements, 145 were recommended, 126 were strongly recommended, and 61 were not recommended. Important aspects of an undergraduate ultrasound curriculum identified include curricular integration across the basic and clinical sciences and a competency and entrustable professional activity-based model. The curriculum should form the foundation of a life-long continuum of ultrasound education that prepares students for advanced training and patient care. In addition, the curriculum should complement and support the medical school curriculum as a whole with enhanced understanding of anatomy, physiology, pathophysiological processes and clinical practice without displacing other important undergraduate learning. The content of the curriculum should be appropriate for the medical student level of training, evidence and expert opinion based, and include ongoing collaborative research and development to ensure optimum educational value and patient care.

CONCLUSIONS

The international consensus conference has provided the first comprehensive document of recommendations for a basic ultrasound curriculum. The document reflects the opinion of a diverse and representative group of international expert ultrasound practitioners, educators, and learners. These recommendations can standardize undergraduate medical student ultrasound education while serving as a basis for additional research in medical education and the application of ultrasound in clinical practice.

Use of artificial intelligence as a didactic tool to improve ejection fraction assessment in the emergency department: A randomized controlled pilot study

OBJECTIVES

Incorporating artificial intelligence (AI) into echocardiography operated by clinicians working in the emergency department to accurately assess left-ventricular ejection fraction (LVEF) may lead to better diagnostic decisions. This randomized controlled pilot study aimed to evaluate AI use as a didactic tool to improve noncardiologist clinicians' assessment of LVEF from the apical 4-chamber (A4ch) view.

METHODS

This prospective randomized controlled pilot study tested the feasibility and acceptability of the incorporation of AI as a didactic tool by comparing the ability of 16 clinicians who work in the emergency department to assess LVEF before and after the introduction of an AI-based ultrasound application. Following a brief didactic course, participants were randomly equally divided into an intervention and a control group. In each of the first and second sessions, both groups were shown 10 echocardiography A4ch clips and asked to assess LVEF. Following each clip assessment, only the intervention group was shown the results of the AI-based tool. For the final session, both groups were presented with a new set of 40 clips and asked to evaluate the LVEF.

RESULTS

In the "normal-abnormal" category evaluation, as related to own baseline accuracy assessment, the intervention group had an improvement in accuracy on 50 consecutive clip assessments compared with a decline in the control group (0.10 vs. -0.12, respectively, p = 0.038). In the "significantly reduced LVEF" category, the intervention group showed significantly less decline in clip assessment as compared to the control group (-0.03 vs. -0.12, respectively, p = 0.050).

CONCLUSIONS

A study involving AI incorporation as a didactic tool for clinicians working in the emergency department appears feasible and acceptable. The introduction of an AI-based tool to clinicians working in the emergency department improved the assessment accuracy of LVEF as compared to the control group.

Deep Learning-Based Automated Echocardiographic Quantification of Left Ventricular Ejection Fraction: A Point-of-Care Solution

BACKGROUND

We have recently tested an automated machine-learning algorithm that quantifies left ventricular (LV) ejection fraction (EF) from guidelines-recommended apical views. However, in the point-of-care (POC) setting, apical 2-chamber views are often difficult to obtain, limiting the usefulness of this approach. Since most POC physicians often rely on visual assessment of apical 4-chamber and parasternal long-axis views, our algorithm was adapted to use either one of these 3 views or any combination. This study aimed to (1) test the accuracy of these automated estimates; (2) determine whether they could be used to accurately classify LV function.

METHODS

Reference EF was obtained using conventional biplane measurements by experienced echocardiographers. In protocol 1, we used echocardiographic images from 166 clinical examinations. Both automated and reference EF values were used to categorize LV function as hyperdynamic (EF>73%), normal (53%-73%), mildly-to-moderately (30%-52%), or severely reduced (<30%). Additionally, LV function was visually estimated for each view by 10 experienced physicians. Accuracy of the detection of reduced LV function (EF<53%) by the automated classification and physicians' interpretation was assessed against the reference classification. In protocol 2, we tested the new machine-learning algorithm in the POC setting on images acquired by nurses using a portable imaging system.

RESULTS

Protocol 1: the agreement with the reference EF values was good (intraclass correlation, 0.86-0.95), with biases <2%. Machine-learning classification of LV function showed similar accuracy to that by physicians in most views, with only 10% to 15% cases where it was less accurate. Protocol 2: the agreement with the reference values was excellent (intraclass correlation=0.84) with a minimal bias of 2.5±6.4%.

CONCLUSIONS

The new machine-learning algorithm allows accurate automated evaluation of LV function from echocardiographic views commonly used in the POC setting. This approach will enable more POC personnel to accurately assess LV function.

A machine learning algorithm supports ultrasound-naïve novices in the acquisition of diagnostic echocardiography loops and provides accurate estimation of LVEF

Left ventricular ejection fraction (LVEF) is the most important parameter in the assessment of cardiac function. A machine-learning algorithm was trained to guide ultrasound-novices to acquire diagnostic echocardiography images. The artificial intelligence (AI) algorithm then estimates LVEF from the captured apical-4-chamber (AP4), apical-2-chamber (AP2), and parasternal-long-axis (PLAX) loops. We sought to test this algorithm by having first-year medical students without previous ultrasound knowledge scan real patients. Nineteen echo-naïve first-year medical students were trained in the basics of echocardiography by a 2.5 h online video tutorial. Each student then scanned three patients with the help of the AI. Image quality was graded according to the American College of Emergency Physicians scale. If rated as diagnostic quality, the AI calculated LVEF from the acquired loops (monoplane and also a "best-LVEF" considering all views acquired in the particular patient). These LVEF calculations were compared to images of the same patients captured and read by three experts (ground-truth LVEF [GT-EF]). The novices acquired diagnostic-quality images in 33/57 (58%), 49/57 (86%), and 39/57 (68%) patients in the PLAX, AP4, and AP2, respectively. At least one of the three views was obtained in 91% of the attempts. We found an excellent agreement between the machine's LVEF calculations from images acquired by the novices with the GT-EF (bias of 3.5% ± 5.6 and r = 0.92, p < 0.001 in the "best-LVEF" algorithm). This pilot study shows first evidence that a machine-learning algorithm can guide ultrasound-novices to acquire diagnostic echo loops and provide an automated LVEF calculation that is in agreement with a human expert.

Perioperative Point-of-Care Ultrasound in Children

Anesthesiologists and other acute care physicians perform and interpret portable ultrasonography-point-of-care ultrasound (POCUS)-at a child's bedside, in the perioperative period. In addition to the established procedural use for central line and nerve block placement, POCUS is being used to guide critical clinical decisions in real-time. Diagnostic point-of-care applications most relevant to the pediatric anesthesiologist include lung ultrasound for assessment of endotracheal tube size and position, pneumothorax, pleural effusion, pneumonia, and atelectasis; cardiac ultrasound for global cardiac function and hydration status, and gastric ultrasound for aspiration risk stratification. This article reviews and discusses select literature regarding the use of various applications of point-of-care ultrasonography in the perioperative period.

Point-of-care ultrasound for the pediatric regional anesthesiologist and pain specialist: a technique review

Point-of-care ultrasound (PoCUS) has been well described for adult perioperative patients; however, the literature on children remains limited. Regional anesthesiologists have gained interest in expanding their clinical repertoire of PoCUS from regional anesthesia to increasing numbers of applications. This manuscript reviews and highlights emerging PoCUS applications that may improve the quality and safety of pediatric care.

In infants and children, lung and airway PoCUS can be used to identify esophageal intubation, size airway devices such as endotracheal tubes, and rule in or out a pulmonary etiology for clinical decompensation. Gastric ultrasound can be used to stratify aspiration risk when nil-per-os compliance and gastric emptying are uncertain. Cardiac PoCUS imaging is useful to triage causes of undifferentiated hypotension or tachycardia and to determine reversible causes of cardiac arrest. Cardiac PoCUS can assess for pericardial effusion, gross ventricular systolic function, cardiac volume and filling, and gross valvular pathology. When PoCUS is used, a more rapid institution of problem-specific therapy with improved patient outcomes is demonstrated in the pediatric emergency medicine and critical care literature.

Overall, PoCUS saves time, expedites the differential diagnosis, and helps direct therapy when used in infants and children. PoCUS is low risk and should be readily accessible to pediatric anesthesiologists in the operating room.

Physicians' abilities to obtain and interpret focused cardiac ultrasound images from critically ill patients after a 2-day training course

Background

This study aimed to determine whether a focused 2-day cardiac ultrasound training course could enable physicians to obtain and interpret focused cardiac ultrasound (FCU) images from critically ill patients.

Methods

We retrospectively reviewed the FCU images submitted by the physicians who attended a 2-day FCU training courses. Three experienced trainers reviewed the images separately. They determined whether the images were assessable and scored the images on an 8-point scale. They also decided whether the physicians provided correct responses for visual estimations of the left ventricular ejection fraction (LVEF) and right ventricle (RV) dilatation and septal motion.

Results

Among the 327 physicians, 291 obtained images that were considered assessable (89%). The scores for parasternal short-axis view were lower than those obtained for other transthoracic echocardiographic views, p < 0.001. More physicians provided incorrect appraisals of LVEF than of RV dilatation and septal motion (19.9% vs. 3.1%, p < 0.001). The percentages of incorrect answers by LVEF category were as follows: 34.8% on images of LVEF < 30, 24.7% on images of LVEF 30–54, and 16.4% on images of LVEF ≥55%, p < 0.001. A logistic regression analysis showed that patients with abnormal LVEF were associated with physicians’ incorrect assessment of LVEF, with an odds ratio of 1.923 (95% confidence interval (CI):1.071–3.456, p = 0.029).

Conclusions

A large proportion of physicians could obtain and interpret FCU images from critically ill patients after a 2-day training course. However, they still scored low on the parasternal short-axis view and were more likely to make an incorrect assessment of LVEF in patients with abnormal left ventricular systolic function.

Image quality to estimate ventricular ejection fraction by last year medical students improves after short courses of training

BACKGROUND

Transthoracic echocardiography is the primary imaging modality for diagnosing cardiac conditions but medical education in this field is limited. We tested the hypothesis that a structured theoretical and supervised practical course of training in focused echocardiography in last year medical students results in a more accurate assessment and more precise calculation of left ventricular ejection fraction after ten patient examinations.

METHODS

After a theoretical introduction course 25 last year medical students performed ten transthoracic echocardiographic examination blocks in postsurgical patients. Left ventricular function was evaluated both with an eye-balling method and with the calculated ejection fraction using diameter and area of left ventricles. Each examination block was controlled by a certified and blinded tutor. Bias and precision of measurements were assessed with Bland and Altman method.

RESULTS

Using the eye-balling method students agreed with the tutor's findings both at the beginning (88%) but more at the end of the course (95.7%). The variation between student and tutor for calculation of area, diameter and ejection fraction, respectively, was significantly lower in examination block 10 than in examination block 1 (each p < 0.001). Students underestimated both the length and the area of the left ventricle at the outset, as complete imaging of the left heart in the ultrasound sector was initially unsuccessful.

CONCLUSIONS

A structured theoretical and practical transthoracic echocardiography course of training for last year medical students provides a clear and measurable learning experience in assessing and measuring left ventricular function. At least 14 examination blocks are necessary to achieve 90% agreement of correct determination of the ejection fraction.

Automated Echocardiographic Quantification of Left Ventricular Ejection Fraction Without Volume Measurements Using a Machine Learning Algorithm Mimicking a Human Expert

BACKGROUND

Echocardiographic quantification of left ventricular (LV) ejection fraction (EF) relies on either manual or automated identification of endocardial boundaries followed by model-based calculation of end-systolic and end-diastolic LV volumes. Recent developments in artificial intelligence resulted in computer algorithms that allow near automated detection of endocardial boundaries and measurement of LV volumes and function. However, boundary identification is still prone to errors limiting accuracy in certain patients. We hypothesized that a fully automated machine learning algorithm could circumvent border detection and instead would estimate the degree of ventricular contraction, similar to a human expert trained on tens of thousands of images.

METHODS

Machine learning algorithm was developed and trained to automatically estimate LVEF on a database of >50 000 echocardiographic studies, including multiple apical 2- and 4-chamber views (AutoEF, BayLabs). Testing was performed on an independent group of 99 patients, whose automated EF values were compared with reference values obtained by averaging measurements by 3 experts using conventional volume-based technique. Inter-technique agreement was assessed using linear regression and Bland-Altman analysis. Consistency was assessed by mean absolute deviation among automated estimates from different combinations of apical views. Finally, sensitivity and specificity of detecting of EF ≤35% were calculated. These metrics were compared side-by-side against the same reference standard to those obtained from conventional EF measurements by clinical readers.

RESULTS

Automated estimation of LVEF was feasible in all 99 patients. AutoEF values showed high consistency (mean absolute deviation =2.9%) and excellent agreement with the reference values: r=0.95, bias=1.0%, limits of agreement =±11.8%, with sensitivity 0.90 and specificity 0.92 for detection of EF ≤35%. This was similar to clinicians' measurements: r=0.94, bias=1.4%, limits of agreement =±13.4%, sensitivity 0.93, specificity 0.87.

CONCLUSIONS

Machine learning algorithm for volume-independent LVEF estimation is highly feasible and similar in accuracy to conventional volume-based measurements, when compared with reference values provided by an expert panel.

Learning curve-cumulative summation analysis of visual estimation of left ventricular function in novice practitioners: A STROBE-compliant article

The aim of the present study was to determine the value of cumulative summation (CUSUM) analysis in assessing the proficiency of novice practitioners in estimating the left ventricular ejection fraction (EF).Seven novice practitioners with no echocardiography experience were recruited in this observational study. Each practitioner assessed EF from echocardiographic video files of 100 cases, one by one, and received feedback and teaching. We obtained a CUSUM score through comparison of the gold standard values of EF and the EF values determined by the practitioners. Then, the practitioners underwent the same test 4 weeks later, except without feedback and teaching, using echocardiographic video files from 100 other cases.The mean number of visual estimation cases required to pass the learning curve (LC)-CUSUM test was 56.3 ± 9.1 (95% CI 47.8-64.7). The LC-CUSUM average of the 7 novice practitioners showed improvement in visual estimation skill, with an average acceptable level achieved after a mean experience of 55 cases. In the test performed after 4 weeks, 5 of the 7 novice practitioners showed significantly good overall agreement. All novice practitioners had a kappa coefficient greater than .8, and significant and almost perfect agreement was observed. All the participants exhibited a percentage of correct answers greater than 81%.We found that the novice practitioners could acquire an acceptable level of skill for estimating EF with short-term, self-learning-focused echocardiographic training.

Synopsis of the point-of-care ultrasound assessment for perioperative emergencies

This module will introduce the concept of a point-of-care ultrasound (POCUS) examination for perioperative clinicians. A focused cardiac examination of ventricular filling and function is presented. An examination of the inferior vena cava is also reviewed as a tool to assess volume status. Finally, a brief examination of the lung and pleura is explored to aid the clinician in situations of patient hypoxia and difficult ventilation. Limited ultrasound cardiorespiratory examinations can be performed by non-cardiologists and non-radiologists. Information drawn from POCUS may aid in diagnosis and early rescue in perioperative care. Point-of-care ultrasound is likely to become standard of care for anesthesiologists in the same way that stethoscopy is presently.

Video clip training improved emergency medicine residents’ interpretation ability of visual ejection fraction

Background:

Information on cardiac contractility is very important in resuscitation of critically ill patients. However, the measurement of ejection fractions by echocardiography is very difficult to perform for non-cardiologists. We developed a video clip to train emergency medicine residents to measure visual ejection fraction and compared the improvement in their interpretation ability with that following the conventional training method.

Objectives:

Improvement of interpreting ability of vEF in short period.

Methods:

A total of 27 multicentre emergency medicine residents were recruited and divided into conventional training group (N = 13) and video clip training group (N = 14). Self-training was done for 1 week. Pre-test and post-test comprising 20 questions were used for evaluation, and scores and interpretation time were recorded.

Results:

The score of the video clip training group showed a statistically significant improvement in contrast to the conventional training group (the score of pre- and post-test, ±5% scoring method: correct answer; video clip training group, 5.4/20 to 10.4/20 ( p < 0.001) versus conventional training group, 5.8/20 to 6.7/20 ( p = 0.204)). Furthermore, there was a statistically significant reduction in the interpretation time (interpretation time of video clip training group, 417.7–358.8 s ( p = 0.005) versus conventional training group, 416.8–411.5 s ( p = 0. 497)).

Conclusion:

In the video clip training group, interpretation accuracy improved, and the interpretation time was shorter than that of the conventional training group. Based on these results, we conclude that improvement in the visual ejection fraction interpretation ability by emergency medicine residents can be expected.

Physicians' Ability to Visually Estimate Left Ventricular Ejection Fraction, Right Ventricular Enlargement, and Paradoxical Septal Motion After a 2-Day Focused Cardiac Ultrasound Training Course

OBJECTIVE

Focused cardiac ultrasound (FCU) can provide useful information for the management of shock and acute respiratory distress syndrome. This study aimed to determine whether a 2-day focused cardiac ultrasound training course could enable critical care physicians to interpret ultrasound images in terms of left ventricular ejection fraction (LVEF), ratio of right ventricular end-diastolic area to left ventricular end-diastolic area (R/LVEDA), and septal kinetics.

DESIGN

A prospective analysis of an image test score.

SETTING

Ultrasound training programs in 7 regions across China.

PARTICIPANTS

Two hundred forty-seven critical care physicians.

INTERVENTIONS

All participants received a 2-day FCU training, including 4 sessions of basic heart function appraisal, 3 sessions of hands-on practice, and 1 session of image interpretation.

MEASUREMENTS AND MAIN RESULTS

The post-training total scores were considerably higher than those of pretraining (75.6% v 58.9%, respectively, p < 0.001). After the course, the trainees obtained considerably higher scores on images with LVEF <30% than on images with LVEF 30% to 54% and LVEF ≥55% (100% v 60.0% and 60.0%, respectively, p < 0.001). The trainees obtained considerably higher scores on images with R/LVEDA >1 than on images with R/LVEDA 0.6 to 1 and R/LVEDA <0.6 (90.0% v 80.0% and 80.0%, p = 0.042 and p < 0.001, respectively). The trainees obtained considerably higher scores on images with paradoxical septal movement (PSM) than on images without PSM (100% v 75.0%, respectively, p < 0.001).

CONCLUSION

The physicians' abilities to assess LVEF, RV enlargement, and PSM improved after the training course, and they demonstrated more accurate estimations of the most obviously abnormal images.

Consensus Document of the SEMI, semFYC, SEN, and SEC on Focused Cardiac Ultrasound in Spain

This document summarizes the concept of focused cardiac ultrasound, the basic technical aspects related to this technique, and its diagnostic objectives. It also defines training requisites in focused cardiac ultrasound. This consensus document has been endorsed by the Spanish Society of Internal Medicine (SEMI), the Spanish Society of Family and Community Medicine (semFYC), the Spanish Society of Neurology (SEN), and the Spanish Society of Cardiology (SEC).

Rapid decay of transthoracic echocardiography skills at 1 month: A prospective observational study

OBJECTIVE

Focused transthoracic echocardiography (FTTE) is an emerging tool in the management of critically ill patients, but the lack of adequate training models has limited the expansion of this technology. Although basic FTTE training courses have been shown to be sufficient in developing echocardiography skills, limited data exist regarding skill retention. In an effort to develop an adequate FTTE training model, we sought to determine the degree of skill retention after FTTE training.

DESIGN

A prospective, observational study.

SETTING

An academic center.

PARTICIPANTS

Surgical residents and medical students: 31 subjects were enrolled from February to June 2016.

RESULTS

Participants underwent a 2-hour FTTE course including didactics and a hands-on session measuring ejection fraction of left ventricle (LV) and inferior vena cava (IVC) diameter. Written knowledge and performance examinations applying FTTE were conducted before the course, immediately after, and at 1- and 3-month intervals, which were evaluated on a 0 to 9 scale and analyzed with paired t-tests. Performance examination scores obtaining the LV and IVC views preinitial and postinitial training increased from 1.7 to 6.5 (LV) and from 2.0 to 6.8 (IVC) (p < 0.01), decreased to 5.0 and 4.8, respectively, at 1 month (posttraining vs 1 month, p < 0.01), and did not significantly change at 3 months (5.4 and 5.0, respectively). Written examination scores increased from 42% to 62% (pretraining vs posttraining, p < 0.01), decreased to 48% in 1 month (posttraining vs 1 month, p < 0.01), and further decreased to 34% at 3 months (1 month vs 3 month, p < 0.01).

CONCLUSIONS

Although a short training course appears sufficient to impart basic FTTE skills and knowledge, skills are significantly decayed at 1 month and knowledge continually decreases at 1 and 3 months. Future FTTE training models should consider the rapid degradation of knowledge and skills in determining frequency of refresher training and ongoing evaluation.

[Consensus on Perioperative Transesophageal Echocardiography of the Brazilian Society of Anesthesiology and the Department of Cardiovascular Image of the Brazilian Society of Cardiology]

Through the Life Cycle of Intraoperative Transesophageal Echocardiography (ETTI/SBA) the Brazilian Society of Anesthesiology, together with the Department of Cardiovascular Image of the Brazilian Society of Cardiology (DIC/SBC), createded a task force to standardize the use of intraoperative transesophageal echocardiography by Brazilian anesthesiologists and echocardiographers based on scientific evidence from the Society of Cardiovascular Anesthesiologists/American Society of Echocardiography (SCA/ASE) and the Brazilian Society of Cardiology.

Consensus on Perioperative Transesophageal Echocardiography of the Brazilian Society of Anesthesiology and the Department of Cardiovascular Image of the Brazilian Society of Cardiology

Through the Life Cycle of Intraoperative Transesophageal Echocardiography (ETTI/SBA) the Brazilian Society of Anesthesiology, together with the Department of Cardiovascular Image of the Brazilian Society of Cardiology (DIC/SBC), created a task force to standardize the use of intraoperative transesophageal echocardiography by Brazilian anesthesiologists and echocardiographers based on scientific evidence from the Society of Cardiovascular Anesthesiologists/American Society of Echocardiography (SCA/ASE) and the Brazilian Society of Cardiology.

Echocardiography and Focused Cardiac Ultrasound

OBJECTIVES

The following review will describe the use of focused cardiac ultrasound performed by noncardiologists and its role as an acute hemodynamic monitoring tool in pediatric cardiac critical care.

DATA SOURCE

MEDLINE and PubMed.

CONCLUSION

The use of focused cardiac ultrasound has grown tremendously over recent years, and is increasingly being performed and interpreted by intensivists, anesthesiologists, and emergency medicine physicians. These imaging techniques are useful in establishing etiologies of cardiac dysfunction and should compliment the physical examination and standard hemodynamic monitoring.

[Perioperative transesophageal echocardiography in non-cardiac surgery. Update]

AIM

The aim of this article is to impart knowledge concerning focused transesophageal echocardiographic examination (TEE) for non-cardiac surgery which is an essential part of perioperative monitoring. It allows a rapid echocardiographic examination without interference with the surgical field or under limited transthoracic examination conditions. New recommendations for a comprehensive perioperative TEE examination with expanded standard views and the recently published consensus statement for a shortened baseline examination were crucial for this study.

MATERIAL AND METHODS

The background is the peer-reviewed literature from PubMed.

RESULTS

Apart from cardiac surgery TEE has two main applications: firstly, the evaluation of patients developing acute life-threatening hemodynamic instability in the operating room, in the emergency room or in the intensive care unit (ICU). Secondly, TEE is used as planned intraoperative monitoring when severe hemodynamic, pulmonary or neurological complications are expected because of the type of surgery or due to the cardiopulmonary medical history of the patient. In 2013 a total of 11 relevant standard views were defined for the basic perioperative TEE examination in non-cardiac surgery. These 11 views should be performed for each patient. Appropriate extension to a comprehensive examination may be necessary if complex pathology is obvious.

DISCUSSION

Even in non-cardiac surgery TEE is an important tool allowing clarification of a life-threatening perioperative hemodynamic instability within a few minutes. Furthermore, the hemodynamic management of high-risk patients can be facilitated. Appropriate qualification and continuous training are necessary in order to assure the competence of the examiner.

International evidence-based recommendations for focused cardiac ultrasound

BACKGROUND

Focused cardiac ultrasound (FoCUS) is a simplified, clinician-performed application of echocardiography that is rapidly expanding in use, especially in emergency and critical care medicine. Performed by appropriately trained clinicians, typically not cardiologists, FoCUS ascertains the essential information needed in critical scenarios for time-sensitive clinical decision making. A need exists for quality evidence-based review and clinical recommendations on its use.

METHODS

The World Interactive Network Focused on Critical UltraSound conducted an international, multispecialty, evidence-based, methodologically rigorous consensus process on FoCUS. Thirty-three experts from 16 countries were involved. A systematic multiple-database, double-track literature search (January 1980 to September 2013) was performed. The Grading of Recommendation, Assessment, Development and Evaluation method was used to determine the quality of available evidence and subsequent development of the recommendations. Evidence-based panel judgment and consensus was collected and analyzed by means of the RAND appropriateness method.

RESULTS

During four conferences (in New Delhi, Milan, Boston, and Barcelona), 108 statements were elaborated and discussed. Face-to-face debates were held in two rounds using the modified Delphi technique. Disagreement occurred for 10 statements. Weak or conditional recommendations were made for two statements and strong or very strong recommendations for 96. These recommendations delineate the nature, applications, technique, potential benefits, clinical integration, education, and certification principles for FoCUS, both for adults and pediatric patients.

CONCLUSIONS

This document presents the results of the first International Conference on FoCUS. For the first time, evidence-based clinical recommendations comprehensively address this branch of point-of-care ultrasound, providing a framework for FoCUS to standardize its application in different clinical settings around the world.

Effects of ultrasound implementation on physical examination learning and teaching during the first year of medical education

OBJECTIVES

Increasing emphasis has been placed on point-of-care ultrasound in medical school. The overall effects of ultrasound curriculum implementation on the traditional physical examination skills of medical students are still unknown. We studied the effects on the Objective Standardized Clinical Examination (OSCE) scores of year 1 medical students before and after ultrasound curriculum implementation.

METHODS

An ultrasound curriculum was incorporated into the physical diagnosis course for year 1 medical students in the 2012-2013 academic year. We performed a prospective observational study comparing traditional OSCE scores of year 1 medical students exposed to the ultrasound curriculum (post-ultrasound) versus historic year 1 medical student controls (pre-ultrasound) with no ultrasound exposure. Questionnaire data were also obtained from year 1 medical students and physical diagnosis faculty to assess attitudes toward ultrasound implementation.

RESULTS

The final overall OSCE scores were graded with a 5-point Likert-type scale from unsatisfactory to outstanding. There was a significant increase in outstanding scores in the post-ultrasound compared to the pre-ultrasound group (27.0% versus 10.9%; P< .001). The post-ultrasound group had significantly (P< .05) increased first-time pass rates on blood pressure measurements, the abdominal examination, and professionalism. Student and physical diagnosis faculty questionnaire data showed an overall positive response, with most agreeing or strongly agreeing that ultrasound should be included in the future year 1 medical student curriculum.

CONCLUSIONS

Ultrasound implementation into a physical diagnosis curriculum for year 1 medical students is feasible and may improve their overall traditional physical examination skills.

Bedside ultrasonography: Applications in critical care: Part I

There is increasing interest in the use of ultrasound to assess and guide the management of critically ill patients. The ability to carry out quick examinations by the bedside to answer specific clinical queries as well as repeatability are clear advantages in an acute care setting. In addition, delays associated with transfer of patients out of the Intensive Care Unit (ICU) and exposure to ionizing radiation may also be avoided. Ultrasonographic imaging looks set to evolve and complement clinical examination of acutely ill patients, offering quick answers by the bedside. In this two-part narrative review, we describe the applications of ultrasonography with a special focus on the management of the critically ill. Part I explores the utility of echocardiography in the ICU, with emphasis on its usefulness in the management of hemodynamically unstable patients. We also discuss lung ultrasonography - a vastly underutilized technology for several years, until intensivists began to realize its usefulness, and obvious advantages over chest radiography. Ultrasonography is rapidly emerging as an important tool in the hands of intensive care physicians.

Focused critical care echocardiography

OBJECTIVE

Portable ultrasound is now used routinely in many ICUs for various clinical applications. Echocardiography performed by noncardiologists, both transesophageal and transthoracic, has evolved to broad applications in diagnosis, monitoring, and management of critically ill patients. This review provides a current update on focused critical care echocardiography for the management of critically ill patients.

METHOD

Source data were obtained from a PubMed search of the medical literature, including the PubMed "related articles" search methodology.

SUMMARY AND CONCLUSIONS

Although studies demonstrating improved clinical outcomes for critically ill patients managed by focused critical care echocardiography are generally lacking, there is evidence to suggest that some intermediate outcomes are improved. Furthermore, noncardiologists can learn focused critical care echocardiography and adequately interpret the information obtained. Noncardiologists can also successfully incorporate focused critical care echocardiography into advanced cardiopulmonary life support. Formal training and proctoring are important for safe application of focused critical care echocardiography in clinical practice. Further outcomes-based research is urgently needed to evaluate the efficacy of focused critical care echocardiography.

Advances in pediatric cardiac intensive care

Pediatric cardiac critical care has made, and continues to make, significant strides in improving outcomes. It is a measure of these successes that much of the discussion in this article does not focus on the reduction of mortality, but rather on perioperative management strategies intended to improve neurologic outcomes. The care of children with critical cardiac disease will continue to rely on broad and collaborative efforts by specialists and primary care practitioners to build on this foundation of success.

An alternative approach to the bedside assessment of left ventricular systolic function in the emergency department: displacement of the aortic root

OBJECTIVES

Left ventricular ejection fraction (LVEF) is a crucial parameter in the management of patients with dyspnea in the emergency department (ED). The use of techniques other than echocardiography such as nuclear or magnetic resonance imaging to measure LVEF is unsuitable in the ED because of time constraints. This study aimed to compare echocardiographic aortic root (AR) excursion and LVEF measurement using the modified Simpson's method (biplane method of disks) as recommended by the American Society of Echocardiography.

METHODS

After 2 hours of theoretical video and hands-on training with 20 patients by an experienced echocardiographer, two emergency physicians prospectively evaluated patients with dyspnea. Two-dimensional echocardiograms of the parasternal long-axis view were obtained, and the displacement of the aortic root (DAR) was studied. M-mode DAR recordings were obtained, and distances were measured as the maximized anterior displacement of the AR from the horizontal axis at end-systole by using the leading-edge methodology. LVEF was measured by an experienced cardiologist using the modified Simpson's rule. The sensitivity, specificity, positive and negative likelihood ratios (LR+, LR-), and positive and negative predictive values (PPV, NPV) were analyzed. A new formula for the prediction of the ejection fraction (EF) with the aid of DAR was then created.

RESULTS

The mean (±SD) age with of the 70 study patients was 69.7 (±11.91) years. In these patients, DAR was highly correlated with EF (point biserial correlation coefficient = 0.79, p < 0.001) and one-way analysis of variance (ANOVA) results were significant (F = 115.9; p < 0.001). The sensitivity was 94.4; specificity, 94.1; LR+, 16.6; LR-, 0.059; PPV, 94.4; and NPV, 94.1.

CONCLUSIONS

The results indicate that DAR is a sensitive index of left ventricular systolic function (SF) and can be used to reliably predict EF values using the rough formula of EF = 20 + 44 (DAR).

Performance of a Simplified Wall Motion Score Index Method for Noncardiologists to Assess Left Ventricular Ejection Fraction

Backgrounds. For emergency physicians performing a goal-directed transthoracic echocardiogram (TTE), a reliable estimate of LVEF must be obtained rapidly. We compared rapid LVEF estimates obtained from short axis sections to those obtained from apical sections using two methods of evaluation. Methods. The TTE's of 6 patients were interpreted by 16 echo-proficient readers (PRO group) and 105 novice readers (NOV group). LVEF was assessed by each group. The strategies consisted of either a global visual estimation (VIS) of LVEF or semiquantitative (SQ) methods. Results. Using RNV and BIP as a reference standard, NOV readers performed better with the SQ method than global visual estimation. For NOV readers, best agreement was achieved with the 234C sequence in low LVEF situations, but with the BMA series in normal LVEF settings. Neither series of views was better than the other in the setting of mild LVEF depression. Conclusion. Semi-quantitative method was superior to global visual estimation of LVEF in NOV group in most of the LVEF ranges.

Echocardiography for hemodynamic evaluation in the intensive care unit

The use of echocardiography in the intensive care unit for patients in shock allows the accurate measurement of several hemodynamic variables in a noninvasive way. By using echocardiography as a hemodynamic monitoring tool, the clinician can evaluate several aspects of shock states, such as cardiac output and fluid responsiveness, myocardial contractility, intracavitary pressures, and biventricular interactions. However, to date, there have been few guidelines suggesting an objective hemodynamic-based examination in the intensive care unit, and most intensivists are usually not familiar with this tool. In this review, we describe some of the most important hemodynamic parameters that can be obtained at the bedside with transthoracic echocardiography.

Right ventricular function assessment: comparison of geometric and visual method to short-axis slice summation method

BACKGROUND

Short-axis summation (SAS) method applied for right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) measurement with cardiac MRI is time consuming and cumbersome to use. A simplified RVEF measurement is desirable. We compare two such methods, a simplified ellipsoid geometric method (GM) and visual estimate, to the SAS method to determine their accuracy and reproducibility.

METHODS

Forty patients undergoing cine cardiac MRI scan were enrolled. The images acquired were analyzed by the SAS method, the GM (area and length measurement from two orthogonal planes) and visual estimate. RVEF was calculated using all three methods and RV volumes using the SAS and GM. Bland-Altman analysis was applied to test the agreement between the various measurements.

RESULTS

Mean RVEF was 49 +/- 12% measured by SAS method, 54 +/- 12% by the GM, and 49 +/- 11% by visual estimate. There were similar bias and limits of agreement between the visual estimate and the GM compared to SAS. The interobserver variability showed a bias close to zero with limits of agreement within +/-10% absolute increments of RVEF in 35 of the patients. The RV end-diastolic volume by GM showed wider limits of agreement. The RV end-systolic volume by GM was underestimated by around 10 ml compared to SAS.

CONCLUSION

Both the visual estimate and the GM had similar bias and limits of agreement when compared to SAS. Though the end-systolic measurement is somewhat underestimated, the geometric method may be useful for serial volume measurements.

Quantitative left ventricular systolic function: From chamber to myocardium

One of the most common indications for obtaining a Doppler echocardiographic study is to ascertain left ventricular (LV) systolic function. There are many ways in which LV function can be determined, but an important assumption that is often overlooked is that every measure that we commonly use is only a surrogate marker of LV function due to the fact that it is impossible to characterize the complex geometric and volumetric function of the ventricle (or myocyte) in a single number. Stated in another way, there is no one perfect measure of LV function. The ejection fraction has emerged as the preeminent method to express LV performance, but although ejection fraction is universally accepted, there are a number of other techniques that can assess LV function and, when taken together, provide a more comprehensive picture both of global and regional LV function. Each of these measures (including ejection fraction) has variable dependence on loading conditions, heart rate, and geometric position that limits its accuracy. Understanding the limitations of each measure will allow the physician to more intelligently understand the true status of the myocardium.

Sensitivity and inter-observer variability for capsule endoscopy image analysis in a cohort of novice readers

AIM: To determine the performance of novice readers (4^th year medical students) for detecting capsule endoscopy findings.

METHODS: Ten capsule endoscopy cases of small bowel lesions were administered to the readers. Gold standard findings were pre-defined by gastroenterologists. Ten gold standard “targets” were identified among the 10 cases. Readers were given a 30-min overview of Rapid Reader software and instructed to mark any potential areas of abnormalities. A software program was developed using SAS to analyze the thumbnailed findings.

RESULTS: The overall sensitivity for detecting the gold standard findings was 80%. As a group, at least 5 out of 10 readers detected each gold standard finding per recording. All the gold standard targets were identified when the readers’ results were combined. Incidental finding/false positive rate ranged between 8.2-59.8 per reader.

CONCLUSION: A panel of medical students with minimal endoscopic experience can achieve high sensitivity in detecting lesions on capsule endoscopy. A group of novice readers can pre-screen recordings to thumbnail potential areas of small bowel lesions for further review. These thumbnails must be reviewed to determine the clinical relevance. Further studies are ongoing to assess other cohorts.

Technology Insight: hand-carried ultrasound cardiac assessment—evolution, not revolution

Hand-carried ultrasound devices can enhance the art of bedside physical examination by increasing diagnostic accuracy, detecting disease at an earlier stage, and improving triage and referral of patients. Although limitations of device cost and portability can be overcome with technologic advances, the shortage of standardized imaging and training opportunities now needs to be addressed to move the technique forward. Cardiologists are the best-qualified subspecialists to design and teach a simplified training program for bedside use of hand-carried ultrasound devices to assess the cardiovascular system.