Feasibility, Accuracy, and Reproducibility of Aortic Valve Sizing for Transcatheter Aortic Valve Implantation Using Virtual Reality.

BACKGROUND: Detailed visualization and precise measurements of aortic valve dimensions are critical for the success of transcatheter aortic valve implantation and for the prevention of complications. Currently, multislice computed tomography is the gold standard for assessment of the aortic annulus and surrounding structures to determine the prosthesis size. New technologies such as virtual reality (VR) not only enable 3-dimensional (3D) visualization with the potential to improve understanding of anatomy and pathology but also allow measurements in 3D. This study aims to investigate the feasibility, accuracy, and reproducibility of VR for the visualization of the aortic valve, the surrounding structures, and its role in preprocedural sizing for transcatheter aortic valve implantation. METHODS AND RESULTS: Based on the preprocedural multislice computed tomography data, 3mensio measurements and 3D visualizations and measurements using VR software were performed retrospectively on 60 consecutive patients who underwent transcatheter aortic valve implantation at our heart center. There were no significant differences but strong correlations between the VR measurements compared with those performed with the 3mensio software. Furthermore, excellent or good intra- and interobserver reliability could be demonstrated for all values. In a structured questionnaire, users reported that VR simplified anatomical understanding, improved 3D comprehension of adjacent structures, and was associated with very good self-perceived depth perception. CONCLUSIONS: The use of VR for preprocedural transcatheter aortic valve implantation sizing is feasible and has precise and reproducible measurements. In addition, 3D visualization improves anatomical understanding and orientation. To evaluate the potential benefits of 3D visualization for planning further cardiovascular interventions, research in this field is needed.

A comparison of conventional and advanced 3D imaging techniques for percutaneous left atrial appendage closure.

Background: Understanding complex cardiac anatomy is essential for percutaneous left atrial appendage (LAA) closure. Conventional multi-slice computed tomography (MSCT) and transesophageal echocardiography (TEE) are now supported by advanced 3D printing and virtual reality (VR) techniques for three-dimensional visualization of volumetric data sets. This study aimed to investigate their added value for LAA closure procedures. Methods: Ten patients scheduled for interventional LAA closure were evaluated with MSCT and TEE. Patient-specific 3D printings and VR models were fabricated based on MSCT data. Ten cardiologists then comparatively assessed LAA anatomy and its procedure relevant surrounding structures with all four imaging modalities and rated their procedural utility on a 5-point Likert scale questionnaire (from 1 = strongly agree to 5 = strongly disagree). Results: Device sizing was rated highest in MSCT (MSCT: 1.9 ± 0.8; TEE: 2.6 ± 0.9; 3D printing: 2.5 ± 1.0; VR: 2.5 ± 1.1; p < 0.01); TEE, VR, and 3D printing were superior in the visualization of the Fossa ovalis compared to MSCT (MSCT: 3.3 ± 1.4; TEE: 2.2 ± 1.3; 3D printing: 2.2 ± 1.4; VR: 1.9 ± 1.3; all p < 0.01). The major strength of VR and 3D printing techniques was a superior depth perception (VR: 1.6 ± 0.5; 3D printing: 1.8 ± 0.4; TEE: 2.9 ± 0.7; MSCT: 2.6 ± 0.8; p < 0.01). The visualization of extracardiac structures was rated less accurate in TEE than MSCT (TEE: 2.6 ± 0.9; MSCT: 1.9 ± 0.8, p < 0.01). However, 3D printing and VR insufficiently visualized extracardiac structures in the present study. Conclusion: A true 3D visualization in VR or 3D printing provides an additional value in the evaluation of the LAA for the planning of percutaneous closure. In particular, the superior perception of depth was seen as a strength of a 3D visualization. This may contribute to a better overall understanding of the anatomy. Clinical studies are needed to evaluate whether a more comprehensive understanding through advanced multimodal imaging of patient-specific anatomy using VR may translate into improved procedural outcomes.

Echocardiographic-Fluoroscopic Fusion Imaging Improves Interventionalists' Learning Curve for Percutaneous Left Atrial Appendage Closure-Initial, Single-Center, Retrospective Observations.

Due to the complex and variable anatomy of the left atrial appendage, percutaneous left atrial appendage closure (LAAC) can be challenging. In this study, we investigated the impact of fusion imaging (FI) on the LAAC learning curve of two interventionalists. The first interventionalist (IC 1) was initially trained without FI and continued his training with FI. The second interventionalist (IC 2) performed all procedures with FI. We compared the first 36 procedures without FI of IC 1 (group 1) with his next 36 interventions with FI (group 2). Furthermore, group 1 was compared to 36 procedures of IC 2 who directly started his training with FI (group 3). Group 1 demonstrated that the learning curve without FI has a flat course with weak correlations for fluoroscopy time, contrast volume, and procedure time, but not for dose area product. Group 2 with FI showed improvement with a steep course and strong correlations for all four parameters. In group 3, we also saw a steep progression with strong correlations. Furthermore, the mean measurements of the parameters in the groups with FI decreased significantly as an indicator of procedural efficacy. We demonstrated that FI may improve the learning curve of experienced and non-experienced ICs.

Left atrial appendage sizing for percutaneous closure in virtual reality-a feasibility study.

Background and aims: The complex and highly variable three-dimensional anatomy of the left atrial appendage (LAA) makes planning and device sizing for interventional occlusion procedures (LAAC) challenging. Several imaging modalities [e.g. echocardiography, multi-slice computed tomography (MSCT)] are used for this purpose. Virtual reality (VR) is an emerging imaging technique to immerse into a three-dimensional left atrium and appendage, offering unprecedented options of visualization and measurement. This study aimed to investigate the feasibility, accuracy and reproducibility of visualizing the LAA in VR for preprocedural planning of LAAC. Methods and results: Twenty-one patients (79 ± 7 years, 62% male) who underwent LAAC at University Hospital Düsseldorf were included in our study. A dedicated software generated three-dimensional VR models from preprocedural MSCT imaging data. Conventional measurements of LAA dimensions (ostium, landing zone and depth) using a commercially available software were compared to measurements in VR: MSCT and VR ostium min. (r = 0.93), max. (r = 0.80) and mean (r = 0.88, all p < 0.001) diameters as well as landing zone (LZ) min. (r = 0.84), max. (r = 0.86) and mean diameters (r = 0.90, all p < 0.001) showed strong correlations. Three-dimensional orientation was judged superior by physicians in VR compared to MSCT (p < 0.05). Conclusion: Virtual reality visualization of the left atrium and appendage based on MSCT data is feasible and allows precise and reproducible measurements in planning of LAA occlusion procedures with enhanced 3D orientation. Further studies need to explore additional benefits of three-dimensional visualization for operators in preprocedural planning.

Virtual and augmented reality in critical care medicine: the patient's, clinician's, and researcher's perspective.

Virtual reality (VR) and augmented reality (AR) are aspiring, new technologies with increasing use in critical care medicine. While VR fully immerses the user into a virtual three-dimensional space, AR adds overlaid virtual elements into a real-world environment. VR and AR offer great potential to improve critical care medicine for patients, relatives and health care providers. VR may help to ameliorate anxiety, stress, fear, and pain for the patient. It may assist patients in mobilisation and rehabilitation and can improve communication between all those involved in the patient's care. AR can be an effective tool to support continuous education of intensive care medicine providers, and may complement traditional learning methods to acquire key practical competences such as central venous line placement, cardiopulmonary resuscitation, extracorporeal membrane oxygenation device management or endotracheal intubation. Currently, technical, human, and ethical challenges remain. The adaptation and integration of VR/AR modalities into useful clinical applications that can be used routinely on the ICU is challenging. Users may experience unwanted side effects (so-called "cybersickness") during VR/AR sessions, which may limit its applicability. Furthermore, critically ill patients are one of the most vulnerable patient groups and warrant special ethical considerations if new technologies are to be introduced into their daily care. To date, most studies involving AR/VR in critical care medicine provide only a low level of evidence due to their research design. Here we summarise background information, current developments, and key considerations that should be taken into account for future scientific investigations in this field.

Multi-Slice Computed Tomography Analysis in Patients Undergoing Transcatheter Aortic Valve Replacement - Impact of Workflows on Measurement of Virtual Aortic Annulus and Valve Size.

Exact and reliable measurements of anatomical dimensions in pre-procedural multi-slice computed tomography (MSCT) scans are crucial for optimal valve sizing and clinical results of transcatheter aortic valve replacement (TAVR). This study aimed to investigate interrater reliability between routinely used workflows for pre-procedural analysis. MSCT scans of 329 patients scheduled for TAVR were analyzed using both a 3mensio and SECTRA IDS7 platform. The results were retrospectively compared using the intraclass correlation coefficient, revealing excellent correlation in the analysis of simple diameters and poor correlation in the assessment of more complex structures with impact on calculated valve size.

Safety of transoesophageal echocardiography during structural heart disease interventions under procedural sedation: a single-centre study.

AIMS: The aim of this study was to determine the incidence of transoesophageal echocardiography (TOE)-related adverse events (AEs) during structural heart disease (SHD) interventions and to identify potential risk factors. METHODS AND RESULTS: We retrospectively analysed 898 consecutive patients undergoing TOE-guided SHD interventions under procedural sedation. TOE-related AEs were classified as bleeding complications, mechanical lesions, conversion to general anaesthesia with intubation, and the occurrence of pneumonia. A follow-up was conducted up to 3 months after the intervention. TOE-related AEs were observed in 5.3% of the patients (n = 48). The highest rate of AEs was observed in the percutaneous mitral valve repair (PMVR) group with 8.2% (n = 32), whereas 4.8% (n = 11) of the patients in the left atrial appendage group and 1.8% (n = 5) in the patent foramen ovale/atrial septal defect group developed a TOE-related AE (P = 0.001). The most frequent AE was pneumonia with an incidence of 2.6% (n = 26) in the total cohort. Bleeding events occurred in 1.8% (n = 16) of the patients, mostly in the PMVR group with 2.1% (n = 8). In the multivariate regression analysis, we found a lower haemoglobin {odds ratio (OR) [95% confidence interval (CI)]: 8.82 (0.68-0.98) P = 0.025} and an obstructive sleep apnoea syndrome (OSAS) [OR (95% CI): 2.51 (1.08-5.84) P = 0.033] to be associated with AE. Furthermore, AEs were related to procedural time [OR (95% CI): 1.01 (1.0-1.01) P = 0.056] and oral anticoagulation [OR (95% CI): 1.97 (0.9-4.3) P = 0.076] with borderline significance in the multivariate regression analysis. No persistent damages were observed. CONCLUSION: TOE-related AEs during SHD interventions are clinically relevant. It was highest in patients undergoing PMVR. A lower baseline haemoglobin level and an OSAS were found to be associated with the occurrence of a TOE-related AE.

Real-time echocardiography-fluoroscopy fusion imaging for left atrial appendage closure: prime time for fusion imaging?

BACKGROUND: Real-time echocardiography-fluoroscopy fusion imaging (FI) merges real-time echocardiographic imaging with fluoroscopic images allowing intuitive anatomical spatial orientation during structural heart disease interventions. We aimed to assess the safety and efficacy of FI during percutaneous left atrial appendage closure (LAAC). METHODS: 34 consecutive patients before (-FI) and 121 patients after (+FI) the introduction of FI for LAAC were included in a single-centre study. In-hospital safety parameters were analysed according to adverse event (AE) definition of the Munich consensus document and procedure-related parameters were assessed for efficacy. An ANCOVA was performed to investigate the influence of a learning curve. RESULTS: Time until successful transseptal puncture was significantly reduced as well as total procedure time and the amount of contrast agent used (+FI/-FI:17 ± 6.35 min vs. 22 ± 8.33 min, p = 0.001; +FI/-FI: 50 min IQR 43 min - 60 min vs. 57 min IQR 45 min -70 min; p = 0.013; +FI/-FI: 70 mL, IQR 55 ml-90 mL vs. 152 mL, IQR 107 mL - 205 mL; p < 0.001). However, fluoroscopy time and dose-area product did not differ between both groups. There was no significant difference in the occurrence of in-hospital adverse events (+FI/-FI: 2.5% vs. 0%; p = 0.596). The ANCOVA revealed that the learning curve does not affect procedural efficacy parameters such as procedure time, time to transseptal puncture, amount of contrast agent and dose-area product. CONCLUSIONS: FI for LAAC reduces the total procedure time, the time to successful transseptal puncture and periprocedural amount of contrast agent.

Performance of the CoreValve Evolut R and PRO in Severely Calcified Anatomy: A Propensity Score Matched Analysis.

BACKGROUND: The CoreValve Evolut R and PRO (Medtronic, Minneapolis, MN, USA) are among the newest-generation of self-expandable transcatheter aortic valve replacement (TAVR) devices and show excellent results. Treating patients with severely calcified (SC) native aortic valve anatomy may be challenging because of the increased risk of periprocedural complications. This study investigated the performance of Evolut R and PRO in this special patient subset. METHODS: Patients who underwent TAVR with the CoreValve Evolut R or PRO (n=381) from September 2015 to March 2018 were divided by aortic valve calcification extent. Patients with SC aortic valve anatomy (n=98; men, >2,062 and women, >1,377 Agatston units) were compared with those with non-severely calcified (NCS) aortic valve anatomy after 1:2 propensity score matching. Outcomes were evaluated according to the updated valve academic research consortium criteria. RESULTS: Patients with SC anatomy were older (83 years vs 80 years, p<0.001) and had a smaller aortic valve area (0.63 cm2 vs 0.70 cm2, p=0.028). Pre-dilatation was more often performed (30.6% vs 15.8%, p=0.003) and a permanent pacemaker implantation was more often necessary (32.9% vs 8.8%, p<0.001) in the SC group. None/mild aortic regurgitation (AR) was evenly distributed (SC, 96.9% vs NCS, 99.5%, p=0.109); moderate AR was present in 3.1% of SC patients and in 0.5% of NSC patients. Severe AR was not observed. CONCLUSION: The CoreValve Evolut R and PRO showed good clinical safety profiles and excellent haemodynamic results in patients with SC anatomy and who more often required permanent pacemaker implantation.

Pulmonary artery to ascending aorta ratio by echocardiography: A strong predictor for presence and severity of pulmonary hypertension.

BACKGROUND: The pulmonary artery (PA) to ascending aorta diameter ratio (PA:A) has been evaluated in numerous studies analyzing cardiac magnetic resonance (CMR) and computed tomography (CT) data. Previously, no transthoracic echocardiography (TTE) cutoffs have been published. We sought to evaluate (1) the feasibility to image the pulmonary trunk in a prospective cohort, and (2) the ability of PA:A derived by TTE to predict pulmonary hypertension (PH). METHODS: We performed a post-hoc analysis of a prospectively recruited consecutive cohort of patients referred to our tertiary center cardiology department due to suspicion for PH. Invasive hemodynamic assessment and quasi-simultaneous TTE was performed in all participants. RESULTS: A total of 84 patients were included in the analysis, median age was 70.5 years (IQR 58-75), 46 (55%) were female. The PA was significantly wider in the PH group (28mm vs. 22.5mm, p<0.001) with a resulting median PA:A of 0.84 vs. 0.66 (p<0.001). Both PA diameter (r = 0.524 and r = 0.44, both p<0.001) and PA:A (r = 0.652 and 0.697, both p<0.001) significantly correlated with mPAP and with PVR, respectively. Area under the curve for the detection of PH was 0.853 (95%CI 0.739-0.967, p<0.001). CONCLUSION: The PA can be visualized in almost all echocardiographic exams, especially when it is dilated. A view showing the pulmonary trunk should be included in every routine TTE. An increased PA:A should raise suspicion for PH and prompt further evaluation and follow-up examinations of these patients.

Predicting the presence of coronary artery disease by transesophageal echocardiography.

BACKGROUND: The accuracy of ultrasound signs as predictors for the presence of coronary artery disease (CAD) has been evaluated extensively in the 1990s and 2000s. Imaging quality has improved tremendously over the last decades. HYPOTHESIS: High-end ultrasound systems allow for accurate prediction of the presence or absence of CAD. METHODS: All patients who underwent a transesophageal echocardiography examination (TEE) between 2007 and 2016 and who had coronary angiography within 24 months before or after the TEE were retrospectively evaluated. RESULTS: A total of 242 patients fulfilled the inclusion criteria, 60% were male. Mean age was 70 years (SD ± 13 years). In multivariate regression analysis, plaque in the ascending aorta (odds ratio [OR] 2.51, 95% confidence interval [CI] 1.18-5.32, p = 0.017), plaque in at least one of the thoracic aortic segments (OR 2.07, 95% CI 1.02-4.22, p = 0.045), and the presence of mitral annular calcification (MAC, OR 1.84, 95% CI 1.01-3.36, p = 0.046) were predictors of significant CAD. The isolated finding of aortic stenosis (AS) (OR 2.53, 95%CI 1.23-5.21, p = 0.012) was a significant predictor for the absence of normal coronary arteries. CONCLUSION: With an negative predictive value (NPV) of 80%, the absence of MAC, AS, and aortic plaque makes the presence of significant CAD unlikely. If at least mild AS is present, normal coronary arteries are improbable.

Atherosclerotic plaque detected by transesophageal echocardiography is an independent predictor for all-cause mortality.

Atherosclerotic lesions in the great arteries are frequent findings in the elderly. Numerous studies have shown their strong predictive value for cardiovascular disease, embolic events, and mortality. We sought to determine the risk of all-cause mortality depending on the localization of plaques in the thoracic aorta evaluated by transesophageal echocardiography (TEE). A total of 2,054 patients (median age 65 years, interquartile range 52-73; 58% men) who underwent a TEE examination between 01/2007 and 03/2015 were retrospectively analyzed. For each patient, the presence of atherosclerotic lesions in the ascending aorta, the aortic arch, and in the descending aorta, as well as cardiovascular risk factors and survival were documented. Median follow-up period was 48 months (interquartile range 38-58). Multivariate Cox regression analysis indicated plaque in the ascending aorta (HR of 1.36, 95% CI 1.01-1.83, P = 0.046), the aortic arch (HR of 1.78, 95% CI 1.29-2.45, P < 0.001), the descending aorta (HR of 2.01, 95% CI 1.54-2.77, P < 0.001), and plaque in any part of the thoracic aorta (HR of 1.84, 95% CI 1.42-2.4, P < 0.001), as independent predictors for all-cause mortality after adjusting for age, sex, arterial hypertension, hyperlipidemia, smoking, and diabetes. In this study, we could demonstrate that more than mild plaque at any site of the thoracic aorta predicts all-cause mortality. Assessment of atherosclerotic lesions in all segments of the thoracic aorta should be part of every routine TEE examination.

Echocardiographic evaluation of left ventricular filling pressures in patients with pulmonary hypertension.

Echocardiographic assessment of diastolic dysfunction depends on surrogate parameters. In recent years, guideline committees attempted to combine these parameters to diagnostic flowcharts allowing for correct classification of left ventricular filling pressures (LVFP). The value of these diagnostic tools is limited if the applied surrogate parameters are elevated due to other reasons as is the case with maximal tricuspid regurgitation velocity. We aimed to compare the accuracy of the 2009 and the 2016 guideline recommendations in patients with pulmonary hypertension (PH). We included 101 consecutive patients who underwent right heart catheterization and transthoracic echocardiography for suspicion of PH. For the final analysis, only patients with PH were considered. The 2009 and 2016 recommendations for the assessment of diastolic function by echocardiography were applied on each patient. A total of 63 PH patients were included in the final analysis, 43% had elevated LVFP. By using the 2009 recommendations, sensitivity for correct classification of diastolic dysfunction was 67%, specificity was 82%, area under the curve (AUC) was 0.74. By using the 2016 recommendations, sensitivity for correct classification of diastolic dysfunction was 84%, specificity was 80%, AUC was 0.82. In ROC comparison, the AUC for the 2016 recommendations with 0.82 was significantly better compared to the AUC of 0.74 for the 2009 recommendations (p = 0.04). Our study demonstrates that the 2016 recommendations for echocardiographic evaluation of diastolic function are superior to the 2009 recommendations in estimating left ventricular filling pressures in patients with PH.