Statin intake is associated with muscular side effects, among which the unmasking of latent myopathies and of malignant hyperthermia (MH) susceptibility have been reported. These findings, together ...with experimental data in small animals, prompt speculation that statin therapy may compromise the performance of skeletal muscle during diagnostic in vitro contracture tests (IVCT). In addition, statins might reduce triggering thresholds in susceptible individuals (MHS), or exacerbate MH progression. We sought to obtain empirical data to address these questions.
We compared the responses of 3 different muscles from untreated or simvastatin treated MHS and non-susceptible (MHN) pigs. MHS animals were also invasively monitored for signs of impending MH during sevoflurane anesthesia.
Muscles from statin treated MHS pigs responded with enhanced in vitro contractures to halothane, while responses to caffeine were unaltered by the treatment. Neither agent elicited contractures in muscles from statin treated MHN pigs. In vivo, end- tide pCO2, hemodynamic evolution, plasma pH, potassium and lactate concentrations consistently pointed to mild acceleration of MH development in statin-treated pigs, whereas masseter spasm and rigor faded compared to untreated MHS animals.
The diagnostic sensitivity and specificity of the IVCT remains unchanged by a short-term simvastatin treatment in MHS swine. Evidence of modest enhancement in cardiovascular and metabolic signs of MH, as well as masked pathognomonic muscle rigor observed under simvastatin therapy suggest a potentially misleading influence on the clinical presentation of MH. The findings deserve further study to include other statins and therapeutic regimes.
Transcatheter therapies are a common way to treat cardiovascular diseases. These therapies are complicated by significant anatomical patient-to-patient variations that exist in terms of transcatheter ...vascular pathways. Adding to the complexity of transcatheter procedures, the training tools used for physician education often overlook vast patient-to-patient variations and utilize idealized models of patient anatomy that may be unrealistic. In this study, anatomically accurate models were created from high-resolution images of real patient vasculatures. Using fourteen human cadavers donated for research, we collected high-resolution images to generate 3D computational renderings of various patient anatomies. These models make up the “Transcatheter Pathways Vasculature Database” that can be used for physician education and training, as well as improving transcatheter delivery system design. We performed multiple studies that emphasize the anatomical differences that exist in patient vasculatures. Using 3D printing and virtual reality, we developed educational materials and benchtop models to train physicians using true patient anatomies. These tools can also provide device designers with data to improve their products based on real patient vessels. The “Transcatheter Pathways Vasculature Database” highlights differences between patient vasculatures. By educating and training physicians with patient anatomies that accurately represent significant patient-to-patient variations, learning is more translatable to what is seen in the clinic.
Radiofrequency, a common ablation modality, is used clinically to terminate cardiac arrhythmias. With excessive heating, complications sometimes occur when the applied energy generates
steam pops
, ...which cause release of energy in the form of tissue and/or air emboli. In this study, we investigated numerous parameters potentially associated with intracardiac steam pops including (1) wattage, (2) catheter tip temperature, (3) catheter irrigation, (4) anatomic site, and (5) repeat ablations at a given site. Using unique Visible Heart
®
methodologies in reanimated swine hearts, we visualized 539 ablations; steam pops developed in 140 of these ablations. The incidence of steam pops significantly increased for both nonirrigated and irrigated ablations at 40 W (
p
< 0.005), and for nonirrigated ablations with catheter contact angles perpendicular to the tissue or that encompassed larger surface areas (
p
< 0.05). To minimize the incidence of steam pops, clinicians performing radiofrequency ablations must consider catheter parameters.
Many lung donor offers are refused despite increasing demand. Portable normothermic ex vivo lung perfusion (EVLP) could increase donor yield by monitoring and reconditioning extended criteria donor ...(ECD) lungs. We report its use in human lungs declined for clinical transplantation. Ten sets of such lungs were procured from brain‐dead donors and underwent 24 hours of normothermic EVLP using a perfusate based on donor whole blood. Hemodynamic and ventilatory data and P:F ratios were measured. Advanced donor age and borderline oxygenation (donor mean P:F 228 ± 73) were the most commonly cited reasons for refusal for transplantation. There was no significant worsening of pulmonary hemodynamics or compliance or significant P:F decline during preservation in the overall cohort. Mean P:F ratio in the overall cohort was 315 ± 88 mm Hg after 24 hours EVLP. At EVLP termination 5/10 lung blocks met standard EVLP thresholds for acceptability for transplant. Eventual EVLP performance was poorly predicted by donor P:F ratio but well predicted by data gathered early in EVLP. Portable normothermic EVLP is useful for transportation, monitoring, and reconditioning of ECD lungs. Early EVLP measurements are more effective than preprocurement donor P:F in predicting eventual allograft performance. We advocate an aggressive strategy of evaluation of ECD lungs using blood‐based EVLP.
Direct visualisation of the BASILICA technique post TAVR to enhance coronary flow Zhingre Sanchez, Jorge D; Iles, Tinen L; Dvir, Danny ...
EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology,
2020-Oct-23, Volume:
16, Issue:
8
Journal Article
The European Bifurcation Club (EBC) supports a continuous review of the field of coronary artery bifurcation interventions and aims to facilitate a scientific discussion and an exchange of ideas on ...the management of bifurcation disease. The recent focus of meetings and consensus statements has been on the technical issues in bifurcation stenting, recognising that the final result of a bifurcation procedure and the long-term outcome for our patients are strongly influenced by factors, including preprocedural strategy, stenting technique selection, performance of optimal procedural steps, the ability to identify and correct complications and finally, and most important, the overall performance of the operator. Continuous refinement of bifurcation stenting techniques and the promotion of education and training in bifurcation stenting techniques represent a major clinical need. Accordingly, the consensus from the latest EBC meeting in Brussels, October 2021, was to promote education and training in bifurcation stenting based on the EBC principle. Part II of this 16th EBC consensus document aims to provide a step-by-step overview of the pitfalls and technical troubleshooting during the implantation of the second stent either in the provisional stenting (PS) strategy or in upfront 2-stent techniques (e.g., 2-stent PS pathway and double kissing crush stenting). Finally, a detailed overview and discussion of the numerous modalities available to provide continuous education and technical training in bifurcation stenting techniques are discussed, with consideration of their future application in enhancing training and practice in coronary bifurcation lesion treatment.
Computational modelling plays an important role in right ventricular (RV) haemodynamic analysis. However, current approaches use smoothed ventricular anatomies. The aim of this study is to ...characterise RV haemodynamics including detailed endocardial structures like trabeculae, moderator band, and papillary muscles. Four paired detailed and smoothed RV endocardium models (2 male and 2 female) were reconstructed from ex vivo human hearts high‐resolution magnetic resonance images. Detailed models include structures with ≥1 mm2 cross‐sectional area. Haemodynamic characterisation was done by computational fluid dynamics simulations with steady and transient inflows, using high‐performance computing. The differences between the flows in smoothed and detailed models were assessed using Q‐criterion for vorticity quantification, the pressure drop between inlet and outlet, and the wall shear stress. Results demonstrated that detailed endocardial structures increase the degree of intra‐ventricular pressure drop, decrease the wall shear stress, and disrupt the dominant vortex creating secondary small vortices. Increasingly turbulent blood flow was observed in the detailed RVs. Female RVs were less trabeculated and presented lower pressure drops than the males. In conclusion, neglecting endocardial structures in RV haemodynamic models may lead to inaccurate conclusions about the pressures, stresses, and blood flow behaviour in the cavity.
The effect of detailed endocardial structures on RV haemodynamics was investigated using CFD simulations; trabeculae down to 1 mm2 cross‐sectional area were segmented from human perfused hearts. Smoothed vs detailed models showed that ventricular trabeculations and papillary muscles increase the intra‐ventricular pressure drop, decrease the wall shear stress, cause turbulent flow and generate secondary vortices, absent in smoothed geometry simulations. The highest correlation to the pressure drop magnitude was the angle at which the inlet and outlet valves are located.
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