Misidentification of the True Aortic Annulus With 2-dimensional Echocardiography: A Critical Appraisal Using 3-Dimensional Imaging.

OBJECTIVES: This study aimed to evaluate the accuracy of identifying the true aortic valve (AV) annulus using 2-dimensional (2D) echocardiography, with the goal of highlighting potential misidentification issues in clinical practice. DESIGN: An observational study employing 3-dimensional (3D) datasets to generate 2D images of the AV annulus for analysis. SETTING: The study was conducted in an academic medical center. PARTICIPANTS: Three-dimensional transesophageal echocardiography datasets were obtained from 11 patients with normal AV and aortic root anatomies undergoing coronary artery bypass surgery. Attending anesthesiologists certified by the National Board of Echocardiography (NBE) were approached subsequently to participate in this study. INTERVENTIONS: Two images per patient were generated from 3D datasets, reflecting the mid-esophageal long-axis view of the AV, a true AV annulus image, and an off-axis image. A survey was distributed to NBE-certified perioperative echocardiographers across 12 academic institutions to identify the true AV annulus from these images. MEASUREMENTS AND MAIN RESULTS: The survey, completed by 45 qualified respondents, revealed a significant misidentification rate of the true AV annulus, with only 36.8% of responses correctly identifying it. The rate of correct identification varied across image sets, with 44.4% of participants unable to correctly identify any true AV annulus image. CONCLUSIONS: The study highlighted the limitations of 2D echocardiography in accurately identifying the true AV annulus in complex 3D structures like the aortic root. The findings suggest a need for greater reliance on advanced imaging modalities, such as 3D echocardiography, to improve accuracy in clinical practice.

Artificial Intelligence for Anesthesiology Board-Style Examination Questions: Role of Large Language Models.

New artificial intelligence tools have been developed that have implications for medical usage. Large language models (LLMs), such as the widely used ChatGPT developed by OpenAI, have not been explored in the context of anesthesiology education. Understanding the reliability of various publicly available LLMs for medical specialties could offer insight into their understanding of the physiology, pharmacology, and practical applications of anesthesiology. An exploratory prospective review was conducted using 3 commercially available LLMs--OpenAI's ChatGPT GPT-3.5 version (GPT-3.5), OpenAI's ChatGPT GPT-4 (GPT-4), and Google's Bard--on questions from a widely used anesthesia board examination review book. Of the 884 eligible questions, the overall correct answer rates were 47.9% for GPT-3.5, 69.4% for GPT-4, and 45.2% for Bard. GPT-4 exhibited significantly higher performance than both GPT-3.5 and Bard (p = 0.001 and p < 0.001, respectively). None of the LLMs met the criteria required to secure American Board of Anesthesiology certification, according to the 70% passing score approximation. GPT-4 significantly outperformed GPT-3.5 and Bard in terms of overall performance, but lacked consistency in providing explanations that aligned with scientific and medical consensus. Although GPT-4 shows promise, current LLMs are not sufficiently advanced to answer anesthesiology board examination questions with passing success. Further iterations and domain-specific training may enhance their utility in medical education.

A Multidisciplinary Protocolized Approach for Ruptured Abdominal Aortic Aneurysm Management: A Retrospective Before-After Study.

OBJECTIVES: To investigate whether implementation of a multidisciplinary protocol for ruptured abdominal aortic aneurysm (rAAA) management reduces rates of adverse complications. DESIGN: A retrospective before-after study. SETTING: A tertiary-care academic hospital. PARTICIPANTS: Adult patients who underwent open or endovascular rAAA repair; data were stratified into before-protocol implementation (group 1: 2015-2018) and after-protocol implementation (group 2: 2019-2022) groups. INTERVENTION: The protocol details the workflow for vascular surgery, anesthesia, emergency department, and operating room staff for a rAAA case; training was accomplished through yearly workshops. MEASUREMENTS AND MAIN RESULTS: The primary outcome was in-hospital mortality. Secondary outcomes included all-cause morbidity and other major complications. Differences in postoperative complication rates between groups were assessed using Pearson's χ2 test. Of the 77 patients included undergoing rAAA repair, 41 (53.2%) patients were in group 1, and 36 (46.8%) patients were in group 2. Patients in group 2 had a significantly shorter median time to incision (1.0 v 0.7 hours, p = 0.022) and total procedure time (180.0 v 160.5 minutes, p = 0.039) for both endovascular and open repair. After protocol implementation, patients undergoing endovascular repair exhibited significantly lower rates of mortality (46.2% v 20.0%, p = 0.048), all-cause morbidity (65.4% v 44.0%, p = 0.050), and renal complications (15.4% v 0.0%, p = 0.036); patients undergoing open repair for a rAAA exhibited significantly lower rates of mortality (53.3% v 27.3%, p = 0.018) and bowel ischemia (26.7% v 0.0%, p = 0.035). CONCLUSIONS: Implementation of a multidisciplinary protocol for the management of a rAAA may reduce rates of adverse complications and improve the quality of care.

Complete and incomplete bridge type double-orifice mitral valve: Diagnosis and characterization with three-dimensional transesophageal echocardiography.

Double orifice mitral valve is a rare congenital anomaly that is often associated with other congenital cardiac abnormalities. Patients may present with valvular dysfunction or may be asymptomatic and have an incidental diagnosis of double outlet mitral valve. Whether symptoms due to this pathology are present or not it is important to accurately characterize this lesion. Three-dimensional imaging is a powerful diagnostic modality for diagnosing and characterizing lesions such as this as highlighted in this case image series where we describe how three-dimensional transesophageal echocardiography was utilized to characterize both complete and incomplete bridge type double orifice mitral valve.

Echocardiographic Outcomes With Transcatheter Edge-to-Edge Repair for Degenerative Mitral Regurgitation in Prohibitive Surgical Risk Patients.

BACKGROUND: The CLASP IID randomized trial (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial) demonstrated the safety and effectiveness of the PASCAL system for mitral transcatheter edge-to-edge repair (M-TEER) in patients at prohibitive surgical risk with significant symptomatic degenerative mitral regurgitation (DMR). OBJECTIVES: This study describes the echocardiographic methods and outcomes from the CLASP IID trial and analyzes baseline variables associated with residual mitral regurgitation (MR) ≤1+. METHODS: An independent echocardiographic core laboratory assessed echocardiographic parameters based on American Society of Echocardiography guidelines focusing on MR mechanism, severity, and feasibility of M-TEER. Factors associated with residual MR ≤1+ were identified using logistic regression. RESULTS: In 180 randomized patients, baseline echocardiographic parameters were well matched between the PASCAL (n = 117) and MitraClip (n = 63) groups, with flail leaflets present in 79.2% of patients. Baseline MR was 4+ in 76.4% and 3+ in 23.6% of patients. All patients achieved MR ≤2+ at discharge. The proportion of patients with MR ≤1+ was similar in both groups at discharge but diverged at 6 months, favoring PASCAL (83.7% vs 71.2%). Overall, patients with a smaller flail gap were significantly more likely to achieve MR ≤1+ at discharge (adjusted OR: 0.70; 95% CI: 0.50-0.99). Patients treated with PASCAL and those with a smaller flail gap were significantly more likely to sustain MR ≤1+ to 6 months (adjusted OR: 2.72 and 0.76; 95% CI: 1.08-6.89 and 0.60-0.98, respectively). CONCLUSIONS: The study used DMR-specific echocardiographic methodology for M-TEER reflecting current guidelines and advances in 3-dimensional echocardiography. Treatment with PASCAL and a smaller flail gap were significant factors in sustaining MR ≤1+ to 6 months. Results demonstrate that MR ≤1+ is an achievable benchmark for successful M-TEER. (Edwards PASCAL TrAnScatheter Valve RePair System Pivotal Clinical Trial [CLASP IID]; NCT03706833).

Novel Three-Dimensionally Printed Ultrasound Probe Simulator and Heart Model for Transthoracic Echocardiography Education.

Simulation-based training is an essential component in the education of transthoracic echocardiography (TTE). Nevertheless, current TTE teaching methods may be subject to certain limitations. Hence, the authors in this study aimed to invent a novel TTE training system employing three-dimensional (3D) printing technology to teach the basic principles and psychomotor skills of TTE imaging more intuitively and understandably. This training system comprises a 3D-printed ultrasound probe simulator and a sliceable heart model. The probe simulator incorporates a linear laser generator to enable the visualization of the projection of the ultrasound scan plane in a 3D space. By using the probe simulator in conjunction with the sliceable heart model or other commercially available anatomic models, trainees can attain a more comprehensive understanding of probe motion and related scan planes in TTE. Notably, the 3D-printed models are portable and low-cost, suggesting their potential utility in various clinical scenarios, particularly for just-in-time training.

Comprehensive Training Model for Procedural Guidance of Transcatheter Mitral Valve Edge-to-Edge Repair: Divide and Conquer Approach.

Transcatheter edge-to-edge repair (TEER) of the mitral valve is a complex procedure requiring continuous image guidance with 2-dimensional and 3-dimensional transesophageal echocardiography. In this context, the role of the echocardiographer is of paramount importance. Training in interventional echocardiography for procedures such as TEER requires comprehending the complicated workflow of the hybrid operating room and advanced imaging skills that go beyond traditional echocardiography training to guide the procedure. Despite TEER being more commonly performed, the training structure for interventional echocardiographers is lagging, with many practitioners not having any formal training in image guidance for this procedure. In this context, novel training strategies must be developed to increase exposure and aid training. In this review, the authors present a step-wise approach to training for image guidance during TEER of the mitral valve. The authors have deconstructed this complex procedure into modular components and have incremental stages of training based on different steps of the procedure. At each step, trainees must demonstrate proficiency before advancing to the next step, thus ensuring a more structured approach to attaining proficiency in this complex procedure.

Regional geometric differences between regurgitant and non-regurgitant mitral valves in patients with coronary artery disease.

OBJECTIVE: Demonstrate that regional geometric differences exist between regurgitant and non-regurgitant mitral valves (MV's) in patients with coronary artery disease and due to the heterogenous and regional nature of ischemic remodeling in patients with coronary artery disease (CAD), that the available anatomical reserve and likelihood of developing mitral regurgitation (MR) is variable in non-regurgitant MV's in patients with CAD. METHODS: In this retrospective, observational study intraoperative three-dimensional transesophageal echocardiographic data was analyzed in patients undergoing coronary revascularization with MR (IMR group) and without MR (NMR group). Regional geometric differences between both groups were assessed and MV reserve which was defined as the increase in antero-posterior (AP) annular diameter from baseline that would lead to coaptation failure was calculated in three zones of the MV from antero-lateral (zone 1), middle (zone 2), and posteromedial (zone 3). MEASUREMENTS AND MAIN RESULTS: There were 31 patients in the IMR group and 93 patients in the NMR group. Multiple regional geometric differences existed between both groups. Most significantly patients in the NMR group had significantly larger coaptation length and MV reserve than the IMR group in zones 1 (p-value = .005, .049) and 2 (p-value = .00, .00), comparable between the two groups in zone 3 (p-value = .436, .513). Depletion of the MV reserve was associated with posterior displacement of the coaptation point in zones 2 and 3. CONCLUSIONS: There are significant regional geometric differences between regurgitant and non-regurgitant MV's in patients with coronary artery disease. Due to regional variations in available anatomical reserve and the risk of coaptation failure in patients with CAD, absence of MR is not synonymous with normal MV function.

Structural and Electrical Integrity of Transesophageal Echocardiography Probes: Importance and Key Concepts.

The clinical utility of transesophageal echocardiography (TEE) is well-established for patients undergoing cardiac surgery. With the increase in percutaneous structural heart disease procedures that rely on TEE for procedural guidance, the use of TEE probes is expanding. Although there are well-established protocols for routine cleaning and decontaminating TEE probes between patient use, there is a lack of awareness and misconceptions about maintaining TEE probes' structural and electrical integrity. The electrical leakage test (ELT) is routinely performed between patient use. From a patient safety standpoint, the ELT is necessary to ensure the longevity of this expensive equipment and prevent disruptions to the workflow in a busy department caused by TEE probes being decommissioned due to probe damage. This technical communication aims to highlight the importance of maintaining TEE probes' structural and electrical integrity. The article also highlights and discusses probe handling techniques between patient use, emphasizing the ELT to ensure patient safety and compliance with national and international standards.

Evaluation of the Effects of an Extubation Protocol With Neostigmine on Duration of Mechanical Ventilation After Cardiac Surgery.

OBJECTIVES: Residual neuromuscular blockade is associated with increased postoperative pulmonary complications. This study aimed to evaluate the effect of an extubation protocol incorporating neuromuscular blockade reversal (NMBR) by train-of-four monitoring on "fast-track" cardiac surgery outcomes. DESIGN: A retrospective cohort study. SETTING: At a university hospital. PARTICIPANTS: Out of 1,843 cardiac surgery patients, from February 2, 2015, to March 31, 2017, 957 (52%) underwent cardiac surgery on or after February 29, 2016. INTERVENTIONS: An extubation protocol, comprised of weaning from mechanical ventilation and NMBR guidelines, was implemented on February 29, 2016. MEASUREMENTS AND MAIN RESULTS: The associations of baseline characteristics with the postoperative duration of mechanical ventilation (primary outcome) and respiratory and/or adverse complications (secondary outcomes) were evaluated using regression and interrupted- time series models. The implementation of an extubation protocol was associated with an 18% decrease in the duration of mechanical ventilation (incident rate ratio [IRR] 0.82, 95% CI 0.72-0.94; p < 0.01), statistically insignificant 26% increase in patients extubated ≤6 hours (odds ratio [OR] 1.26, 95% CI 0.97-1.65; p = 0.09), and 13% shorter intensive care unit length of stay (LOS) (IRR 0.87, 95% CI 0.79-0.97; p < 0.01). Patients undergoing isolated coronary artery bypass graft or isolated valve procedures, on or after February 29, 2016, had decreased extubation times (IRR 0.82, p < 0.01 and IRR 0.80, p = 0.02). The protocol did not have a statistically significant association with hospital LOS (IRR 0.98, p = 0.57) or readmission (OR 1.22, p = 0.33), and differences in the occurrence of pulmonary complications and adverse outcomes between the pre- and postprotocol groups were clinically insignificant. CONCLUSIONS: The application of an extubation protocol incorporating NMBR based on neuromuscular monitoring was associated with a decrease in postoperative duration of mechanical ventilation and facilitated more patients meeting the early extubation benchmark without an increased risk of respiratory complications or adverse outcomes.

Novel Three-Dimensional Printed Human Heart Models and Ultrasound Omniplane Simulator for Transesophageal Echocardiography Training.

Simulation-based training plays an essential role in transesophageal echocardiography (TEE) education. Using 3-dimensional printing technology, the authors invented a novel TEE teaching system consisting of a series of heart models that can be segmented according to actual TEE views, and an ultrasound omniplane simulator to demonstrate how ultrasound beams intersect the heart at different angles and generate images. This novel teaching system is able to provide a more direct way to visualize the mechanics of obtaining TEE images than traditional online or mannequin-based simulators. It can also provide tangible feedback of both an ultrasound scan plane and a TEE view of the heart, which has been proven to improve trainees' spatial awareness and can significantly help in understanding and memorizing complex anatomic structures. This teaching system itself is also portable and inexpensive, making it conducive to teaching TEE in regions of diverse economic status. This teaching system also can be expected to be used for just-in-time training in a variety of clinical scenarios, including operating rooms, intensive care units, etc.

Overview of the Interatrial Septum: Review of Cardiac Nomenclature for Transseptal Puncture.

Transseptal puncture is an increasingly common procedure undertaken to gain access to the left side of the heart during structural heart disease interventions. Precision guidance during this procedure is paramount to ensure success and patient safety. As such, multimodality imaging, such as echocardiography, fluoroscopy, and fusion imaging, is routinely used to guide safe transseptal puncture. Despite the use of multimodal imaging, there is currently no uniform nomenclature of cardiac anatomy between the various imaging modes and proceduralists, and echocardiographers tend to use imaging modality-specific terminology when communicating among the various imaging modes. This variability in nomenclature among imaging modes stems from differing anatomic descriptions of cardiac anatomy. Given the required level of precision in performing transseptal puncture, a clearer understanding of the basis of cardiac anatomic nomenclature is required by both echocardiographers as well as proceduralists; enhanced understanding can help facilitate communication across specialties and possibly improve communication and safety. In this review, the authors highlight the variation in cardiac anatomy nomenclature among various imaging modes.

Motion Analysis: An Objective Assessment of Special Operations Forces and Tactical Medics Performing Point-of-Care Ultrasound.

BACKGROUND: Point-of-care ultrasound (POCUS) is commonly employed to image the heart, lungs, and abdomen. Rapid ultrasound for shock and hypotension (RUSH) exams are a critical component of POCUS employed in austere environments by Special Operations Forces (SOF) and tactical medics for triage and diagnosis. Despite its utility, training for POCUS remains largely unstandardized with respect to feedback and markers of proficiency. We hypothesized that motion analysis could objectively identify improvement in medics' performance of RUSH exams. Furthermore, we predicted that motion metrics would correlate with qualitative ratings administered by attending anesthesiologists. METHODS: A team of civilian and military attending anesthesiologists trained 24 medics in POCUS during a 5-day course. Each medic performed eight RUSH exams using an ultrasound probe equipped with an electromagnetic motion sensor to track total distance travelled (path length), movements performed (translational motions), degrees rotated (rotational sum), and time. Instructors (experts) observed and rated the exams on the following items: image finding, image fine-tuning, speed, final image accuracy, and global assessment. Motion metrics were used to provide feedback to medics throughout the course. Generalized estimating equations were used to analyze the trends of motion metrics across all trials. Correlations amongst motion metrics and expert ratings were assessed with Pearson correlation coefficients. RESULTS: Participants exhibited a negative trend in all motion metrics (p < 0.001). Pearson correlation coefficients revealed moderate inverse correlations amongst motion metrics and expert ratings. CONCLUSION: Motion analysis was able to quantify and describe the performance of medics training in POCUS and correlated with expert ratings.

Timing of Blood Transfusions and 30-Day Patient Outcomes After Coronary Artery Bypass Graft Surgery.

OBJECTIVE: Packed red blood cell transfusion during coronary artery bypass graft surgery is known to be associated with adverse outcomes. However, the association of the timing between transfusions in relation to discharge and 30-day postoperative outcomes has not been studied. The study authors investigated the impact of transfusion timing on 30-day surgical outcomes. DESIGN: A retrospective review. SETTING: At a single tertiary-care academic hospital. PARTICIPANTS: A total of 2,481 adult patients underwent primary coronary artery bypass graft surgery between January 2014 and December 2020. MEASUREMENTS AND MAIN RESULTS: The relationship between the timing of packed red blood cell transfusion (intraoperative, postoperative, or both) and 30-day postoperative outcome variables was calculated as an odds ratio. The influence of timing of transfusion on adjusted probability of postoperative complications was plotted against the lowest intraoperative hematocrit. The median age of the population was 67 years (60.0-74.0), body mass index was 28.5 (25.6-32.3) kg/m2, and 497 (20.0%) were female. A total of 1,588 (36%) patients received packed red blood cell transfusions; 182 (7.3%) received intraoperative transfusions, 489 (19.7%) received postoperative transfusions, and 222 (9.0%) received both (intraoperative and postoperative transfusions). Postoperative transfusion was associated with significantly higher odds of readmission (1.83 [1.32-2.54], p = 0.002) and heart failure (1.64 [1.2-2.23], p = 0.008) compared to patients with no transfusions; whereas intraoperative transfusions were not. CONCLUSION: The authors' data suggested that the postoperative timing of transfusion in patients undergoing coronary artery bypass graft surgery may be associated with an increased incidence of 30-day heart failure and readmission. Prospective research is needed to conclusively confirm these findings.

Mitral Valve Coaptation Reserve Index: A Model to Localize Individual Resistance to Mitral Regurgitation Caused by Annular Dilation.

OBJECTIVES: The objective of this study was to develop a mathematical model for mitral annular dilatation simulation and determine its effects on the individualized mitral valve (MV) coaptation reserve index (CRI). DESIGN: A retrospective analysis of intraoperative transesophageal 3-dimensionalechocardiographic MV datasets was performed. A mathematical model was created to assess the mitral CRI for each leaflet segment (A1-P1, A2-P2, A3-P3). Mitral CRI was defined as the ratio between the coaptation reserve (measured coaptation length along the closure line) and an individualized correction factor. Indexing was chosen to correct for MV sphericity and area of largest valve opening. Mathematical models were created to simulate progressive mitral annular dilatation and to predict the effect on the individual mitral CRI. SETTING: At a single-center academic hospital. PARTICIPANTS: Twenty-five patients with normally functioning MVs undergoing cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Direct measurement of leaflet coaptation along the closure line showed the lowest amount of coaptation (reserve) near the commissures (A1-P1 0.21 ± 0.05 cm and A3-P3 0.22 ± 0.06 cm), and the highest amount of coaptation (reserve) at region A2 to P2 0.25 ± 0.06 cm. After indexing, the A2-to-P2 region was the area with the lowest CRI in the majority of patients, and also the area with the least resistance to mitral regurgitation (MR) occurrence after simulation of progressive annular dilation. CONCLUSIONS: Quantification and indexing of mitral coaptation reserve along the closure line are feasible. Indexing and mathematical simulation of progressive annular dilatation consistently showed that indexed coaptation reserve was lowest in the A2-to-P2 region. These results may explain why this area is prone to lose coaptation and is often affected in MR.

Geometric Indices for Predicting Ischemic Mitral Regurgitation: Correlation of Mitral Valve Coaptation Area With Tenting Height, Tenting Area and Tenting Volume.

OBJECTIVES: Ischemic remodeling of the left ventricle in patients with coronary artery disease (CAD) results in geometric changes of the mitral valve (MV) apparatus, leading to reduced MV leaflet coaptation. Although the calculation of the coaptation area has value in assessing the effects of left ventricular remodeling on the MV, it is difficult and time-consuming to measure. In this study the authors hypothesized that the tenting volume (TV) would have a greater association with coaptation area than tenting height (TH) or tenting area (TA). DESIGN: A retrospective review. SETTING: A single tertiary-care academic hospital. PARTICIPANTS: There were 145 adult patients who underwent coronary artery bypass graft surgery between April 2018 and July 2020. MEASUREMENTS AND MAIN RESULTS: Intraoperative 2- and 3-dimensional transesophageal echocardiographic studies were obtained in the precardiopulmonary bypass period. Offline analysis was used to obtain TH, TA, TV and coaptation area for each patient. Correlation between the coaptation area and the TH, TA, and TV was conducted using Pearson's correlation. The median age of the population was 68.0 years (61.0-73.3), the body mass index was 29.0 kg/m2 (25.7-33.5), and 17.8% were females. Increases in TV were the most reliable predictor of decreases in coaptation area (R2 = 0.75) followed by TA (R2 = 0.48) and TH (R2 = 0.47). CONCLUSION: As a representative of the complete topography of the MV, the authors' study demonstrated that in patients with CAD, TV has a greater negative correlation with coaptation area as compared to TH or TA.