Purpose
Minimally invasive mitral valve surgery (MIMVS) and transcatheter edge-to-edge repair (TEER) are complex procedures used to treat mitral valve (MV) pathologies, but with limited training ...opportunities available. To enable training, a realistic hemodynamic environment is needed. In this work we aimed to develop and validate a simulator that enables investigation of MV pathologies and their repair by MIMVS and TEER in a hemodynamic setting.
Methods
Different MVs were installed in the simulator, and pressure, flow, and transesophageal echocardiographic measurements were obtained. To confirm the simulator’s physiological range, we first installed a biological prosthetic, a mechanical prosthetic, and a competent excised porcine MV. Subsequently, we inserted two porcine MVs—one with induced chordae tendineae rupture and the other with a dilated annulus, along with a patient-specific silicone valve extracted from echocardiography with bi-leaflet prolapse. Finally, TEER and MIMVS procedures were conducted by experts to repair the MVs.
Results
Systolic pressures, cardiac outputs, and regurgitations volumes (RVol) with competent MVs were 119 ± 1 mmHg, 4.78 ± 0.16 l min
−1
, and 5 ± 3 ml respectively, and thus within the physiological range. In contrast, the pathological MVs displayed increased RVols. MIMVS and TEER resulted in a decrease in RVols and mitigated the severity of mitral regurgitation.
Conclusion
Ex-vivo modelling of MV pathologies and repair procedures using the described simulator realistically replicated physiological in-vivo conditions. Furthermore, we showed the feasibility of performing MIMVS and TEER at the simulator, also at patient-specific level, thus providing new clinical perspectives in terms of training modalities and personalized planning.
ABSTRACT
Mapping brain function to brain structure is a fundamental task for neuroscience. For such an endeavour, the Drosophila larva is simple enough to be tractable, yet complex enough to be ...interesting. It features about 10,000 neurons and is capable of various taxes, kineses and Pavlovian conditioning. All its neurons are currently being mapped into a light-microscopical atlas, and Gal4 strains are being generated to experimentally access neurons one at a time. In addition, an electron microscopic reconstruction of its nervous system seems within reach. Notably, this electron microscope-based connectome is being drafted for a stage 1 larva – because stage 1 larvae are much smaller than stage 3 larvae. However, most behaviour analyses have been performed for stage 3 larvae because their larger size makes them easier to handle and observe. It is therefore warranted to either redo the electron microscopic reconstruction for a stage 3 larva or to survey the behavioural faculties of stage 1 larvae. We provide the latter. In a community-based approach we called the Ol1mpiad, we probed stage 1 Drosophila larvae for free locomotion, feeding, responsiveness to substrate vibration, gentle and nociceptive touch, burrowing, olfactory preference and thermotaxis, light avoidance, gustatory choice of various tastants plus odour–taste associative learning, as well as light/dark–electric shock associative learning. Quantitatively, stage 1 larvae show lower scores in most tasks, arguably because of their smaller size and lower speed. Qualitatively, however, stage 1 larvae perform strikingly similar to stage 3 larvae in almost all cases. These results bolster confidence in mapping brain structure and behaviour across developmental stages.
Aims
Mitral valve transcatheter edge‐to‐edge repair (TEER) has been established as a suitable alternative to mitral valve surgery in patients with severe mitral regurgitation (MR) and high surgical ...risk. The PASCAL system represents a novel device, potentially augmenting the toolkit for TEER. The aim of this study was to assess and compare short and 1 year safety and efficacy of the PASCAL and MitraClip systems for TEER.
Methods and results
Procedural, short, and 1 year outcomes of a 1:2 propensity‐matched cohort including 41 PASCAL and 82 MitraClip cases were investigated. Matching was based on clinical, laboratory, echocardiographic, and functional characteristics. The primary endpoints assessed were procedural success as defined by the Mitral Valve Academy Research Consortium (MVARC), residual MR, functional class, and a composite endpoint comprising death, heart failure hospitalization, and mitral valve re‐intervention. We found for the PASCAL and the matched MitraClip cohort no significant differences in MVARC defined technical (90.2% vs. 95.1%, P = 0.44), device (90.2% vs. 89.0%, P = 1.0), or procedural (87.8% vs. 80.5%, P = 0.45) success rates. Accordingly, the overall MR reduction and improvement in New York Heart Association (NYHA) class were comparable (1 year follow‐up: MR ≤ 2 95% vs. 93.6%, P = 1.0; NYHA ≤ 2 57.1% vs. 66.7%, P = 0.59). The composite outcome revealed no statistically significant difference between both devices (1 year follow‐up: 31.7% vs. 37.8%, P = 0.55). Interestingly, we found at both short and 1 year follow‐up a significantly higher rate of patients with none or trace MR in the PASCAL‐treated cohort (short follow‐up: 17.9% vs. 0%, P = 0.0081; 1 year follow‐up: 25% vs. 0%, P = 0.0016). Conversely, the rate of aborted device implantations due to an elevated transmitral gradient was higher in PASCAL interventions (9.8% vs. 1.2%, P = 0.04).
Conclusions
Transcatheter edge‐to‐edge repair using the PASCAL or MitraClip device results in favourable and comparable outcomes regarding safety, efficacy, and clinical improvement after 1 year.
The Berlin Heart® EXCOR is a paracorporeal, pulsatile ventricular assist device used in patients of all age groups. However, adolescent and adult patients on EXCOR support are scarcely explored. ...Herein, we present a detailed description of infectious complications in this patient cohort. From 2006 to 2020, 58 patients received a biventricular assist device (BiVAD) at our institution and were included in this study. Postoperative infections were assessed after BiVAD implantation and subsequent heart transplantation (HTx). A Berlin Heart® EXCOR BiVAD was implanted as a bridge to transplantation in 58 patients (12–64 years). Most patients were INTERMACS I, and their median age was 49 years. Wound infections (WI) specific to the ventricular assist device (VAD) occurred in 31 (53.4%) patients with a mean time of 113 ± 155 days after BiVAD implantation. HTx was performed in 30 (51.7%) patients and thereof 10 (33.3%) patients developed at least one WI post-HTx. The mean time of WI after HTx was 17 ± 14 days. In four cases, WIs were caused by the same pathogen as before HTx. According to our institutional BiVAD wound classification, the mean wound score was 3. The VAD-specific wound infections were manageable and did not increase mortality nor precluded HTx in Berlin Heart® EXCOR patients. No specific risk factors for VAD-specific wound infections could be identified.
Aims
Wildtype transthyretin amyloid cardiomyopathy is an under‐recognized cause of heart failure in elderly patients. Transcatheter tricuspid valve repair is a newly emerging therapeutic option for ...severe tricuspid regurgitation (TR). We present first insights into safety and possible benefits of this procedure in patients with cardiac amyloidosis.
Methods and results
Eight patients with cardiac non‐hereditary (wildtype) transthyretin (ATTRwt) amyloidosis and severe to torrential TR, undergoing successful transcatheter tricuspid valve repair, were included in the analysis and compared to a control group of 21 patients without cardiac amyloidosis. All patients presented with an advanced stage of amyloid cardiomyopathy. Primary endpoint was reduction in TR at 3 months follow‐up. Secondary endpoints were feasibility, safety, hospitalization or death, clinical improvement, cardiac biomarkers, and structural and functional right heart parameter obtained by echocardiography. Transcatheter tricuspid valve repair resulted in a significant reduction of TR (IV to II, P = 0.008) in all eight patients with cardiac amyloidosis (100%). Device success (amyloidosis 75% vs. control group 86%, P = 0.597) and overall probability of hospitalization or death (amyloidosis 13% vs. control group 25%, P = 0.646) were similar compared with those in the control group at 3 months follow‐up. Transcatheter tricuspid valve repair led to an improvement of New York Heart Association functional class (P = 0.031) and 6 min walking distance (from 313 ± 118 to 337 ± 106, P = 0.012). TR reduction in amyloidosis patients was less extensive compared with that in control group (TR‐reduction 1.6 ± 0.3, P = 0.008 vs. control group 2.3 ± 0.3, P < 0.0001). Furthermore, these patients showed no significant improvement of structural right heart parameters.
Conclusions
Transcatheter tricuspid valve repair is a safe and feasible new treatment option in patients with amyloid cardiomyopathy and has the potential to improve TR‐grade and clinical status. However, the benefit appears to be less pronounced compared with patients without cardiac amyloidosis.
Transcatheter edge-to-edge repair (TEER) using the MitraClip™ device has been established as a suitable alternative to mitral valve surgery in patients with severe mitral regurgitation (MR) and high ...or prohibitive surgical risk. Only limited information regarding the impact of TEER on ventricular arrhythmias (VA) has been reported. The aim of the present study was to assess the impact of TEER using the MitraClipTM device on the burden of VA and ICD (Implantable Cardioverter Defibrillator) therapies. Among 600 MitraClipTM implantations performed in our clinic between September 2009 and October 2018, we identified 86 patients with successful TEER and an active implantable cardiac device (pacemaker, ICD, CRT-P/D (Cardiac Resynchronization Therapy-Pacemaker/Defibrillator)) eligible for retrospective VA analyses. These patients presented with mainly functional MR (81.4%) and severely reduced left ventricular ejection fraction (mean LVEF 22.1% ± 10.3%). The observation period comprised 456 ± 313 days before and 424 ± 287 days after TEER. The burden of ventricular arrhythmias (sustained ventricular tachycardia (sVT) and ventricular fibrillation (VF)) was significantly reduced after TEER (0.85 ± 3.47 vs. 0.43 ± 2.03 events per patient per month, p = 0.01). Furthermore, the rate of ICD therapies (anti-tachycardia pacing (ATP) and ICD shock) decreased significantly after MitraClipTM implantation (1.0 ± 3.87 vs. 0.32 ± 1.41, p = 0.014). However, reduction of VA burden did not result in improved two-year survival in this patient cohort with severely reduced LVEF. Mitral valve TEER using the MitraClip™ device was associated with a significant reduction of ventricular arrhythmias and ICD therapies.
Tricuspid valve regurgitation (TVR) is often observed after orthotopic heart transplantation. However, there is a scarcity of data regarding long-term outcomes of patients with TVR.
Between January ...2008 and December 2015, 169 patients underwent orthotopic heart transplantation at our center and were included in this study. TVR trends and associated clinical parameters were retrospectively analyzed. TVR was assessed after 30 d, 1 y, 3 y, and 5 y, and groups were defined according to changes in TVR grade: constant (group 1; n = 100), improvement (group 2; n = 26), and deterioration (group 3; n = 43). Survival, outcome with regard to operative technique, and long-term kidney and liver function during follow-up were assessed.
Mean follow-up time was 7.67 ± 4.17 y (median 8.62, Q1 5.06, Q3 11.16). Overall mortality was 42.0%, with differences between the groups (
< 0.01). Cox regression analysis revealed improvement of TVR as a significant predictor for survival (hazard ratio 0.23; 95% confidence interval, 0.08-0.63,
< 0.01). After 1 y 2.7%, after 3 y 3.7%, and after 5 y 3.9% of the patients showed persistent severe TVR. Creatinine levels after 30 d and 1, 3, and 5 y showed significant differences between the groups (
= 0.02,
< 0.01,
< 0.01, and
= 0.01), deterioration of TVR being associated with higher creatinine levels during follow-up.
Deterioration of TVR is associated with higher mortality and renal dysfunction. Improvement of TVR may function as a positive predictor for long-term survival after heart transplantation. Improvement of TVR should be a therapeutic goal offering a prognostic value for long-term survival.
Aims
We investigated short and mid‐term safety and efficacy of the PASCAL system for percutaneous mitral valve repair (PMVr) in severe mitral regurgitation (MR) in an all‐comer population.
Methods ...and results
In the first consecutive 41 patients undergoing PMVr using the PASCAL system in our centre, procedural success and safety were assessed. Efficacy in improving MR and functional class were evaluated. Median patient age was 74 years, 58.5% were male patients, and median European System for Cardiac Operative Risk Evaluation Score II was 5.1%. All patients suffered from severe MR with 59% functional MR, 29% degenerative MR, and 12% of mixed aetiology MR. The technical success rate was 90%, limited by four cases where PASCAL implantation was aborted due to a prohibitive mitral gradient. On average, 1.16 PASCAL devices per patient were implanted. All patients successfully implanted with a PASCAL device were discharged with MR grade ≤ 2 and 79% with MR grade ≤ 1. Mean follow‐up was 8.7 ± 4.9 months. Ninety‐seven per cent of patients remained at MR ≤ 2 at follow‐up, which translated into a significantly improved New York Heart Association functional class as well as a significant reduction of systolic pulmonary artery pressure and brain natriuretic peptide levels. The procedure‐related rate for major adverse events was 3%. Neither early nor late single‐leaflet detachment was found. In one patient, air embolism occurred, resulting in modification of the PASCAL instructions for use.
Conclusions
Percutaneous mitral valve repair using PASCAL in a real‐world, all‐comer population was feasible and safe, resulting in a significant mid‐term reduction of MR with persistent clinical improvement.
Feeding is one of the most fundamental activities of animals. Whether an animal will eat or not depends on sensory cues concerning nutrient availability and quality as well as on its growth, hormonal ...and metabolic state. These diverse signals, which originate from different regions of the body and act on different time scales, must be integrated by the nervous system to enable an appropriate feeding response. Here, we review recent studies in Drosophila melanogaster larvae that aim to elucidate the central circuits that underlie food intake, based on a serial section electron microscopic volume of an entire central nervous system. We focus on the comprehensive mapping of the synaptic connections between the sensory inputs and motor outputs of the larval feeding system. The central feeding circuit can be organized into a series of parallel pathways that connect a given set of input and output neurons. A dominant circuit motif is that of a monosynaptic sensory-motor connection upon which a series of polysynaptic paths are superimposed. The interneurons of the different parallel paths receive slightly different sets of sensory inputs, which enable flexibility in the selection of feeding motor outputs.
Miroschnikow and colleagues review the architecture of the central feeding network of the Drosophila larva and how feeding decisions are made through a series of multiple parallel pathways.
The neural circuits responsible for animal behavior remain largely unknown. We summarize new methods and present the circuitry of a large fraction of the brain of the fruit fly
. Improved methods ...include new procedures to prepare, image, align, segment, find synapses in, and proofread such large data sets. We define cell types, refine computational compartments, and provide an exhaustive atlas of cell examples and types, many of them novel. We provide detailed circuits consisting of neurons and their chemical synapses for most of the central brain. We make the data public and simplify access, reducing the effort needed to answer circuit questions, and provide procedures linking the neurons defined by our analysis with genetic reagents. Biologically, we examine distributions of connection strengths, neural motifs on different scales, electrical consequences of compartmentalization, and evidence that maximizing packing density is an important criterion in the evolution of the fly's brain.
PDF
