Pre-Operative Planning of a DCR Surgery Using Virtual Reality.

PURPOSE: To assess a novel Virtual Reality (VR) tool designed to enhance understanding of the nasal anatomy in patients eligible for DCR surgery. METHODS: Preoperative Computed Tomography (CT) scans of the orbit were obtained and loaded as DICOM (Digital Imaging and Communications in Medicine) files onto the D2P software (3D Systems Inc. Littleton, CO) for tissue segmentation and 3D model preparation. Segmentation was performed on several anatomical structures, including the skull, lacrimal sac, nasal septum, inferior and middle turbinate. The resulting 3D model was visualized using a VR headset. After completing the segmentation procedure, ten cases were evaluated by a panel of six surgeons, including both senior and resident physicians from ENT and oculoplastic specialties. RESULTS: The dataset under examination comprised images from 10 preoperative CT scans of the orbits of patients eligible for Endo-DCR. When evaluating the CT using the VR tool, in 73.3% of the cases ENT surgeons were right about the side of pathology, while only 43.3% ophthalmologists were right (chi-square, p = .018). In 72.8% of the cases ENT surgeons were evaluated right that there is a septum deviation, while only in 47.2% of the cases the ophthalmologists were right (chi-square, p = .094).When evaluating the CT using the VR tool, in 60% of the cases consultants were right about the pathology, while 57.7% of the residents were right (chi-square, p = .853). In 81.7% of the cases consultants were evaluated right that there is a septum deviation, while only in 58.3% of the cases the ophthalmologists were right (chi-square, p = .198). DISCUSSION: ENT surgeons, as well as consultants, interpreted the CT better than the ophthalmologists and residents. Surprisingly, the VR system did not help them to interpret the CT better. Further, more extensive studies should be done to build a VR system that assists in the correct interpretation of the preoperative CT before DCR surgery as well as during DCR surgery.

Virtual Reality-Enhanced Assessment of the Anterior Glottic Angle Using Cadaveric Models: A Proof-of-Concept Study.

OBJECTIVES: Vocal fold paralysis (VFP) is a complex disorder that affects voice, speech, swallowing, and overall quality of life. Current evaluation methods for determining the position of paralyzed vocal folds lack the objectivity required for personalized interventions and research on innovative treatments for VFP. This study was designed to validate the accuracy and reproducibility of a virtual reality (VR)-based platform to measure the anterior glottic angle (AGA), a critical component in determining the position of a paralyzed vocal fold. STUDY DESIGN: Retrospective. METHODS: A retrospective analysis of computed tomography (CT) scans of 39 adult patients was conducted to measure the AGA shortly after death. Two measurement methods were used: 2-dimensional (2D)-CT for direct measurements on 2D images and a 3-dimensional (3D)-VR method utilizing a dedicated platform to create a 3D VR model of the larynx. The AGA measurements conducted by two senior otolaryngologists using the 3D-VR method were compared to the 2D-CT measurements made by one of these same otolaryngologists. RESULTS: The mean AGA measured by the 3D-VR method was found to be 32.936 ± 6.486° (n = 39), and the measurements were highly correlated (r = 0.9670, P < 0.0001). By contrast, the 2D-CT method without VR yielded a significantly lower mean angle of 23.754° (n = 35) with a higher standard deviation of 10.365°. The 3D-VR method demonstrated excellent reliability for AGA measurements (intraclass correlation coefficient of 0.954). CONCLUSION: The findings underscore the potential value of using a VR-based platform to improve reproducibility and reduce the variability in measurements of AGA in cases of VFP.

The Fate of Mitral Valve Surgery in the Pediatric Age: A 25-Year Single-Center Experience.

Background: The aim of this study was to evaluate the natural history of patients after mitral valve intervention in the pediatric age. Methods: This is a retrospective study including all patients who underwent mitral valve surgery from 1998 to 2022. The patients' surgical reports, postoperative records, and ambulatory visits were reviewed. The endpoints of the study were survival and freedom from mitral valve reoperation. Results: Of the 70 patients included in the cohort, 61 patients (86.7%) had congenital mitral valve disease, of whom 46 patients (75.4%) had a predominantly mitral regurgitation lesion, and 15 patients (24.6%) had a predominantly mitral stenosis. In the mitral regurgitation group, all of the patients underwent valve repair with an operative mortality of one patient (2.1%), and with median follow-up of 4 years (range, 0.5-13 years), there was 4.3% mortality (n = 2) and 71.2% freedom from reoperation. In the mitral stenosis group, 11 patients underwent mitral valve repair, and 4 patients underwent valve replacement. There was an operative mortality of two patients (13.3%). With a 2-year median follow-up (range: 0.1-23 years), there were no additional mortality cases in the mitral stenosis group. All three patients who survived primary mitral valve replacement (100%) and four patients who survived a primary repair (40.0%) underwent reoperation. Conclusions: This study demonstrates encouraging outcomes for mitral valve repair. The mortality of patients with congenital mitral valve disease may also be related to a difficult postoperative course, rather than the MV lesion itself.

3D-SARC: A Pilot Study Testing the Use of a 3D Augmented-Reality Model with Conventional Imaging as a Preoperative Assessment Tool for Surgical Resection of Retroperitoneal Sarcoma.

BACKGROUND: Retroperitoneal sarcomas (RPSs) present a surgical challenge, with complex anatomic relationships to organs and vascular structures. This pilot study investigated the role of three-dimensional (3D) augmented reality (3DAR) compared with standard imaging in preoperative planning and resection strategies. METHODS: For the study, 13 patients who underwent surgical resection of their RPS were selected based on the location of their tumor (right, left, pelvis). From the patients' preoperative computed tomography (CT) scans, 3DAR models were created using a D2P program and projected by an augmented-reality (AR) glass (Hololens). The 3DAR models were evaluated by three experienced sarcoma surgeons and compared with the baseline two-dimensional (2D) contrast-enhanced CT scans. RESULTS: Three members of the surgical team evaluated 13 models of retroperitoneal sarcomas, resulting in a total of 26 responses. When the surgical team was asked to evaluate whether the 3DAR better prepared the surgeon for planned surgical resection, 10 responses favored the 3DAR, 5 favored the 2D CT scans and 11 showed no difference (p = 0.074). According to 15 (57.6 %) of the 26 responses, the 3DAR offered additional value over standard imaging in the preoperative planning (median score of 4; range, 1-5). The median stated likelihood that the surgeons would consult the 3DAR was 5 (range, 2-5) for the preoperative setting and 3 (range, 1-5) for the intraoperative setting. CONCLUSIONS: This pilot study suggests that the use of 3DAR may provide additional value over current standard imaging in the preoperative planning for surgical resection of RPS, and the technology merits further study.

Virtual Reality Helps Describe the Progression of Thyroid Cartilage Calcification.

OBJECTIVES: Thyroid cartilage (TC) calcifications may impact surgical planning and clinical management. However, few studies to date have implemented virtual reality (VR) to evaluate these calcifications. This study assessed the feasibility of evaluating TC calcifications in various regions and measuring their volumes through VR models generated from computed tomography scans. We also investigated age and gender-related differences in calcification patterns. METHODS: Ninety-two participants were categorized into younger, middle-aged, and older age groups. Calcification patterns (degree in Hounsfield units and volume of calcification in cm3) in different TC regions were identified by VR analysis, which enabled comparisons between age groups and genders. RESULTS: Significant differences in calcification patterns were observed between males and females, particularly in the middle right, middle left, bottom left, and vertex regions. Age-related differences in the vertex region showed increased calcification in the older age group. CONCLUSION: This study points to the contribution of VR in the evaluation of complex anatomical structures. The findings revealed significant gender and age patterns in TC calcification. These insights can inform surgical planning and highlight the potential of using VR to gain a better understanding of TC calcification clinically.

Current state of the art and future directions for implantable sensors in medical technology: Clinical needs and engineering challenges.

Implantable sensors have revolutionized the way we monitor biophysical and biochemical parameters by enabling real-time closed-loop intervention or therapy. These technologies align with the new era of healthcare known as healthcare 5.0, which encompasses smart disease control and detection, virtual care, intelligent health management, smart monitoring, and decision-making. This review explores the diverse biomedical applications of implantable temperature, mechanical, electrophysiological, optical, and electrochemical sensors. We delve into the engineering principles that serve as the foundation for their development. We also address the challenges faced by researchers and designers in bridging the gap between implantable sensor research and their clinical adoption by emphasizing the importance of careful consideration of clinical requirements and engineering challenges. We highlight the need for future research to explore issues such as long-term performance, biocompatibility, and power sources, as well as the potential for implantable sensors to transform healthcare across multiple disciplines. It is evident that implantable sensors have immense potential in the field of medical technology. However, the gap between research and clinical adoption remains wide, and there are still major obstacles to overcome before they can become a widely adopted part of medical practice.

A Platform for Assessing Cellular Contractile Function Based on Magnetic Manipulation of Magnetoresponsive Hydrogel Films.

Despite significant advancements in in vitro cardiac modeling approaches, researchers still lack the capacity to obtain in vitro measurements of a key indicator of cardiac function: contractility, or stroke volume under specific loading conditions-defined as the pressures to which the heart is subjected prior to and during contraction. This work puts forward a platform that creates this capability, by providing a means of dynamically controlling loading conditions in vitro. This dynamic tissue loading platform consists of a thin magnetoresponsive hydrogel cantilever on which 2D engineered myocardial tissue is cultured. Exposing the cantilever to an external magnetic field-generated by positioning magnets at a controlled distance from the cantilever-causes the hydrogel film to stretch, creating tissue load. Next, cell contraction is induced through electrical stimulation, and the force of the contraction is recorded, by measuring the cantilever's deflection. Force-length-based measurements of contractility are then derived, comparable to clinical measurements. In an illustrative application, the platform is used to measure contractility both in untreated myocardial tissue and in tissue exposed to an inotropic agent. Clear differences are observed between conditions, suggesting that the proposed platform has significant potential to provide clinically relevant measurements of contractility.

Virtual reality-based training and pre-operative planning for head and neck sentinel lymph node biopsy.

OBJECTIVE: Sentinel lymph node biopsy (SLNB) is crucial for managing head and neck skin cancer. However, variable lymphatic drainage can complicate SLN detection when using Single-Photon Emission Computed Tomography (SPECT) or lymphoscintigraphy. Virtual Reality (VR) can contribute to pre-operative planning by simulating a realistic 3D model, which improves orientation. VR can also facilitate real-patient training outside the operating room. This study explored using a VR platform for pre-operative planning in head and neck skin cancer patients undergoing SLNBs and assessed its value for residential training. MATERIALS AND METHODS: In this prospective technology pilot study, attending surgeons and residents who performed 21 SLNB operations on patients with head and neck skin cancers (81% males, mean age 69.2 ± 11.3) used a VR simulation model based on each patient's pre-operative SPECT scan to examine patient-specific anatomy. After surgery, they completed a questionnaire on the efficiency of the VR simulation as a pre-operative planning tool and training device for residents. RESULTS: The attending surgeons rated the VR model's accuracy at 8.3 ± 1.6 out of 10. Three-quarters (76%) of residents reported increased confidence after using VR. The physicians rated the platform's contribution to residents' training at 7.4 ± 2.1 to 8.9 ± 1.3 out of 10. CONCLUSION: A VR SLNB simulation can accurately portray marked sentinel lymph nodes. It was rated high as a surgical planning and teaching tool among attending surgeons and residents alike and may play a role in pre-operative planning and resident training. Further studies are needed to explore its applications in practice.

Virtual reality utilization for left atrial appendage occluder device size prediction.

Aim: To explore the feasibility and accuracy of virtual reality (VR) derived from cardiac computed angiography (CCTA) data to predict left atrial appendage occlusion (LAAO) device size. Method: Retrospective data of patients who underwent LAAO according to clinical indication were reviewed; all patients underwent a pre-procedural CCTA. Measurements of the left atrial appendage (LAA) orifice diameters by CCTA, VR, and transesophageal echocardiography (TEE) (acquired during the procedure) were compared to the implanted device size. The LAA perimeter was calculated using the Ramanujan approximation. Statistical analyses included Lin's Concordance Correlation Coefficient (ρ c ), the mean difference, and the mean square error (MSE). Results: The sample was composed of 20 patients (mean age 75.7 ± 7.5 years, 60% males) who underwent successful LAAO insertion (ACP™ N = 8, Watchman™ N = 12). The CCTA, VR, and TEE maximal diameter ρ c was 0.52, 0.78 and 0.60, respectively with mean differences of +0.92 ± 4.0 mm, -1.12 ± 2.3 mm, and -3.45 ± 2.69 mm, respectively. The CCTA, VR, and TEE perimeter calculations ρ c were 0.49, 0.54, and 0.39 respectively with mean differences of +4.69 ± 11.5 mm, -9.88 ± 8.0 mm, and -16.79 ± 7.8 respectively. Discussion: A VR visualization of the LAA ostium in different perspectives allows for a better understanding of its funnel-shaped structure. VR measurement of the maximal ostium diameter had the strongest correlation with the diameter of the inserted device. VR may thus provide new imaging possibilities for the evaluation of complex pre-procedural structures such as the LAA.

Three-dimensional reconstruction of computed tomography colonography discloses anatomic features associated with colonoscopy failure.

Objectives: Three-dimensional virtual reality (3D VR) permits precise reconstruction of computed tomography (CT) images, and these allow precise measurements of colonic anatomical parameters. Colonoscopy proves challenging in a subset of patients, and thus CT colonoscopy (CTC) is often required to visualize the entire colon. The aim of the study was to determine whether 3D reconstructions of the colon could help identify and quantify the key anatomical features leading to colonoscopy failure. Design: Retrospective observational study. Methods: Using 3D VR technology, we reconstructed and compared the length of various colonic segments and number of bends and colonic width in 10 cases of CTC in technically failed prior colonoscopies to 10 cases of CTC performed for non-technically failure indications. Results: We found significant elongation of the sigmoid colon (71 ± 23 cm versus 35 ± 9; p = 0.01) and of pancolonic length (216 ± 38 cm versus 158 ± 20 cm; p = 0.001) in cases of technically failed colonoscopy. There was also a significant increase in the number of colonic angles (17.7 ± 3.2 versus 12.7 ± 2.4; p = 0.008) in failed colonoscopy cases. Conclusion: Increased sigmoid and pancolonic length and more colonic bends are novel factors associated with technical failure of colonoscopy.

Using Virtual Reality for Deep Inferior Epigastric Perforator Flap Preoperative Planning.

This study was designed to compare VR stereoscopical three-dimensional (3D) imaging with two-dimensional computed tomography angiography (CTA) images for evaluating the abdominal vascular anatomy before autologous breast reconstruction. Methods: This prospective case series feasibility study was conducted in two tertiary medical centers. Participants were women slated to undergo free transverse rectus abdominis muscle, unilateral or bilateral deep inferior epigastric perforator flap immediate breast reconstruction. Based on a routine CTA, a 3D VR model was generated. Before each procedure, the surgeons examined the CTA and then the VR model. Any new information provided by the VR imaging was submitted to a radiologist for confirmation before surgery. Following each procedure, the surgeons completed a questionnaire comparing the two methods. Results: Thirty women between 34 and 68 years of age were included in the study; except for one, all breast reconstructions were successful. The surgeons ranked VR higher than CTA in terms of better anatomical understanding and operative anatomical findings. In 72.4% of cases, VR models were rated having maximum similarity to reality, with no significant difference between the type of perforator anatomical course or complexity. In more than 70% of the cases, VR was considered to have contributed to determining the surgical approach. In four cases, VR imaging modified the surgical strategy, without any complications. Conclusions: VR imaging was well-accepted by the surgeons who commented on its importance and ease compared with the standard CTA presentation. Further studies are needed to determine whether VR should become an integral part of preoperative deep inferior epigastric perforator surgery planning.

Normothermic Versus Hypothermic Norwood Procedure.

BACKGROUND: Either deep hypothermia with circulatory arrest or hypothermic perfusion with antegrade selective cerebral perfusion is used during the Norwood procedure for hypoplastic left heart syndrome. Normothermic perfusion has been described for pediatric patients. The aim of this study was to compare the early outcomes of patients undergoing the Norwood procedure with antegrade selective cerebral perfusion under hypothermia with the procedure under normothermia. METHODS: From 2005 to 2020, 117 consecutive patients with hypoplastic left heart syndrome underwent the Norwood procedure: 68 (58.2%) under hypothermia and 49 (41.8%) under normothermia. Antegrade selective cerebral perfusion flow was adjusted to maintain right radial arterial pressure above 50 mm Hg, and a flow rate of 40 to 50 mL kg-1 min-1. Baseline characteristics, operative data, and postoperative outcomes including lactate recovery time were compared. RESULTS: The baseline characteristics and cardiovascular diagnosis were similar in both groups. The normothermic group had a significantly shorter bypass time (in minutes) of 90.31 (±31.60) versus 123.63 (±25.33), a cross-clamp time of 45.24 (±16.35) versus 81.93 (±16.34), and an antegrade selective cerebral perfusion time of 25.61 (±13.84) versus 47.30 (±14.35) (P < .001). There were no statistically significant differences in the immediate postoperative course, or in terms of in-hospital mortality, which totaled 9 (18.4%) in the normothermic group, and 10 (14.9%) in the hypothermic group (P = .81). CONCLUSION: The normothermic Norwood procedure with selective cerebral perfusion is feasible and safe in terms of in-hospital mortality and short-term outcomes. It is comparable to the standard hypothermic Norwood with selective cerebral perfusion.

Proof of concept: Comparative accuracy of semiautomated VR modeling for volumetric analysis of the heart ventricles.

Introduction: Simpson's rule is generally used to estimate cardiac volumes. By contrast, modern methods such as Virtual Reality (VR) utilize mesh modeling to present the object's surface spatial structure, thus enabling intricate volumetric calculations. In this study, two types of semiautomated VR models for cardiac volumetric analysis were compared to the standard Philips dedicated cardiac imaging platform (PDP) which is based on Simpson's rule calculations. Methods: This retrospective report examined the cardiac computed tomography angiography (CCTA) of twenty patients with atrial fibrillation obtained prior to a left atrial appendage occlusion procedure. We employed two VR models to evaluate each CCTA and compared them to the PDP: a VR model with Philips-similar segmentations (VR-PS) that included the trabeculae and the papillary muscles within the luminal volume, and a VR model that only included the inner blood pool (VR-IBP). Results: Comparison of the VR-PS and the PDP left ventricle (LV) volumes demonstrated excellent correlation with a ρ c of 0.983 (95% CI 0.96, 0.99), and a small mean difference and range. The calculated volumes of the right ventricle (RV) had a somewhat lower correlation of 0.89 (95% CI 0.781, 0.95), a small mean difference, and a broader range. The VR-IBP chamber size estimations were significantly smaller than the estimates based on the PDP. Discussion: Simpson's rule and polygon summation algorithms produce similar results in normal morphological LVs. However, this correlation failed to emerge when applied to RVs and irregular chambers. Conclusions: The findings suggest that the polygon summation method is preferable for RV and irregular LV volume and function calculations.

Comparison of Speckle Tracking Echocardiography During Different Pacing Modalities for Cardiac Resynchronization Therapy Response Prediction.

Background: The aim of this study was to evaluate left ventricular mechanical activation pattern by speckle tracking echocardiography (STE) as a predictor of response to cardiac resynchronization therapy (CRT) in patients with heart failure. Methods: Echocardiography was performed during no pacing, right ventricular pacing (RVP), biventricular pacing (BVP) and multipolar pacing (MPP) immediately after CRT implantation in 16 patients at a single centre. Seven patients were diagnosed as responders and 9 patients as non-responders after 6 months of standard CRT pacing. All had adequate short axis views, and 1 CRT responder and 2 CRT non-responders had limited longitudinal views. Results: Longitudinal and circumferential global strain (GS) and global strain rate (GSR) or their change analysis, did not yield any CRT response prediction. However, the longitudinal BVP/RVP GS ratio was significantly higher in the responder group (1.32 ± 0.2%, 2.0 ± 0.4% and 1.9 ± 0.4%), compared with the non-responder group (1.06 ± 0.2%, 1.1 ± 0.4% and 1.2 ± 0.4%) in the apical two-chamber, APLAX and four-chamber views, respectively. Similarly, the longitudinal BVP/RVP GSR at active systolic phase (GSRs) was significantly higher in the responder group (1.9 ± 0.9% and 1.7 ± 0.4%) compared with the non-responder group (1.0 ± 0.4% and 1.1 ± 0.2%) in the apical APLAX and four-chamber views, respectively. Measurements of the strain delay index showed predictive power regarding CRT response in non-paced patients. Conclusion: Post implantation, longitudinal BVP/RVP GS and GSRs ratios of 1.4% and above may be useful as a CRT response prediction tool. Furthermore, our findings support the usefulness of strain delay index prior to CRT implantation in non-paced patients.

Using Augmented Reality for Intraoperative Guidance During Sacral Neuromodulation System Implantation.

Objective: The purpose of this study was to examine the feasibility of using augmented reality during lead placement for sacral nerve stimulation (SNS). Methods: The study was a prospective case series performed in a single tertiary center. Patients with fecal incontinence or urinary retention eligible for SNS according to the American society of colon and rectal surgeon's guidelines were included. Each patient underwent a computerized tomography scan of the sacrum and pelvic floor before surgery; and a segmentation of the sacral bone, the skin, and three fiducial markers on the lower back was produced. Surgical planning included the design of an ideal virtual transmission tract leading to the S3 foramen using the most suitable location and needle trajectory for introducing the lead. During the surgical intervention, a needle was inserted into the S3 foramen using the aligned tract as visualized using the Microsoft HoloLens first generation head mounted unit. Results: Overall, 11 patients were included. Mean operative time was 43.8 minutes (range 25-81 minutes). All patients reported a significant reduction from the preoperative level of the mean postoperative Cleveland Clinic Incontinence Score (CCIS) assessed 2 weeks after the temporary SNS implant (CCIS preoperative 13.3, postoperative 8.5; CI -7.35 to -2.25; P < 0.01). The surgeons reported the imaging useful, allowing accurate and easier approach. Conclusions: Intraoperative augmented reality imaging for needle application during SNS appears to be feasible, practical, and may be useful in additional procedures.

Inappropriate Shocks and Power Delivery Using Adult Automatic External Defibrillator Pads in a Pediatric Patient.

ABSTRACT: The use of automatic external defibrillators (AEDs) during pulseless resuscitations is considered safe and reliable, and was established as part of the guidelines in out-of-hospital events. Based on extensive studies, the use of the standard AED is now indicated in every age group with a preference of pediatric pad application for small children and babies. If unavailable, adult pads are recommended. We report a case of 2 inappropriate AED shocks that were delivered to a neonate during a pulseless resuscitation after application of adult pads. The 3.6-kg patient received 2 shocks, over 200 J each, for sinus bradycardia that was not detected by the device. Although treated inappropriately with high voltage, no cardiac or skin sequelae were detected, and the patient had normal cardiac and neurological development later on.

Acute hyperglycaemia can impair driving skill in young type 1 diabetes mellitus patients.

AIM: Drivers with diabetes are at increased risk of being involved in road accidents. Therefore, this study aimed to evaluate the effects of acute hyperglycaemia (AH) compared with euglycaemia on driving ability in patients with type 1 diabetes mellitus (T1DM). METHODS: Eighteen drivers with T1DM were asked to navigate twice through nine hazardous scenarios, using a driving simulator, during euglycaemia and then again during AH (mean blood glucose: 138 ± 34 mg/dL and 321 ± 29 mg/dL, respectively) in a counterbalanced crossover study. Driving performance was continually monitored for driving speed, steering wheel angle, acceleration, and location and velocity of other vehicles and obstacles, with drivers wearing a mobile head-mounted eye-tracking system. RESULTS: The main findings were that, during AH, participants were less likely to identify a hazard [probability of identification (POI): 0.5725 ± 0.5], glanced fewer times at the hazard (3.24 ± 5.9), maintained shorter headway (between-vehicle) distance (mean: 40.87 ± 20.15 m) and had an increased number of braking events per km driven (6.69 ± 5.20) compared with driving during euglycaemia (POI: 0.733 ± 0.4; number of glances: 3.69 ± 6.99; headway distance: 50.46 ± 26.2 m; number of braking events per km driven: 4.31 ± 3.87; P < 0.05 for all parameters). CONCLUSION: This study provides evidence that AH impairs driving performance in young T1DM patients by demonstrating the negative effects of AH on both hazard perception and speed management.

New Insights on Genetic Diagnostics in Cardiomyopathy and Arrhythmia Patients Gained by Stepwise Exome Data Analysis.

Inherited cardiomyopathies are characterized by clinical and genetic heterogeneity that challenge genetic diagnostics. In this study, we examined the diagnostic benefit of exome data compared to targeted gene panel analyses, and we propose new candidate genes. We performed exome sequencing in a cohort of 61 consecutive patients with a diagnosis of cardiomyopathy or primary arrhythmia, and we analyzed the data following a stepwise approach. Overall, in 64% of patients, a variant of interest (VOI) was detected. The detection rate in the main sub-cohort consisting of patients with dilated cardiomyopathy (DCM) was much higher than previously reported (25/36; 69%). The majority of VOIs were found in disease-specific panels, while a further analysis of an extended panel and exome data led to an additional diagnostic yield of 13% and 5%, respectively. Exome data analysis also detected variants in candidate genes whose functional profile suggested a probable pathogenetic role, the strongest candidate being a truncating variant in STK38. In conclusion, although the diagnostic yield of gene panels is acceptable for routine diagnostics, the genetic heterogeneity of cardiomyopathies and the presence of still-unknown causes favor exome sequencing, which enables the detection of interesting phenotype-genotype correlations, as well as the identification of novel candidate genes.

The impact of tricuspid valve regurgitation severity on exercise capacity and cardiac-related hospitalisations among adults with non-operated Ebstein's anomaly.

BACKGROUND: Tricuspid valve regurgitation is an inherent part of Ebstein's anomaly, yet whether the severity of the regurgitation further impairs exercise capacity and contributes to long-term morbidity on top of the lesion severity per se is unknown. METHODS: To evaluate for this potential effect, we included 30 patients with Ebstein's anomaly who did not undergo any form of surgical interventions and had a cardiopulmonary exercise test and echocardiographic studies in this retrospective analysis. Echocardiographic studies and cardiopulmonary exercise tests were critically reviewed for lesion severity grade, tricuspid regurgitation degree, and exercise parameters. Cardiac-related hospitalisations were recorded from computerised medical records and during clinic visits. RESULTS: Fourteen patients (47%) had moderate and 8 (27%) had severe regurgitation. Patients with ≥ moderate regurgitation exhibited significantly lower exercise capacity (median % predicted maximal oxygen consumption, 62 versus 79%, p = 0.03) and venilatory efficiency at exercise. When stratifying exercise results by regurgitation degree, a stepwise decrease in oxygen consumption and ventilatory efficiency with increasing regurgitation severity was observed, regardless of the anatomic lesion severity. During a median follow-up of 4.6 years, > moderate tricuspid regurgitation was associated with significantly lower cumulative probability of freedom from cardiac hospitalisations. CONCLUSIONS: We report that among non-operated Ebstein's anomaly patients, greater tricuspid regurgitation severity was associated with worse exercise capacity and with overall higher probability of cardiac-related hospitalisations independent from the underlying lesion severity.