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Deep intramural ventricular tachycardia substrate targets are difficult to access, map, and ablate from endocardial and epicardial surfaces, resulting in high recurrence rates.

Sarcomatoid renal cell carcinoma (RCC) is defined by the presence of any amount of sarcomatoid components admixed with other RCC histologic subtypes. Our investigation utilizes a large, diverse set of sarcomatoid RCC patients to summarize clinical, demographic, and pathological factors along with demographic disparities that may affect the prognosis and survival of sarcomatoid RCC patients.

Transcatheter electrosurgery is a versatile tool that can be used to cut cardiac tissue without the need for a sternotomy, cardiopulmonary bypass, and cardioplegia. With adequate imaging and suitable anatomy, any cardiac tissue can be cut. Thus, transcatheter electrosurgery can provide bespoke therapies for complex patients who often have no other good treatment options. In this review, we will discuss the common applications for electrosurgical tissue traversal and laceration, including transcaval access, BASILICA, LAMPOON, and ELASTA-Clip, summarizing the evidence and the key technical steps for each.

For many neurologic subspecialties, the fellowship application process begins early in the first half of the second year of neurology-specific training (PGY3 for adult neurology residents and PGY4 for child neurology residents). In 2019, the American Academy of Neurology (AAN) published a position statement recommending communication between fellowship candidates and training programs begin no sooner than March 1 of the penultimate year of training and that programs offer fellowship positions no sooner than August 1 of the final year of training. A few pilot subspecialties adopted this timeline for 2021 recruitment for positions beginning in 2022. All United States–based AAN-affiliated neurology and child neurology residents who recently completed the fellowship application process received a survey about their fellowship application experience. Of the 291 residents who responded to the survey, 96% agree that applications should not be submitted before March 1 of the penultimate year of training and 72% believe that August 1 of the final year is a reasonable time to begin offering positions. Nearly half (49%) of residents believe that there is too little time for subspecialty/clinical exposure before applying for fellowship and 88% feel the current process and timeline are stressful. Residents who applied to programs in pilot subspecialties report more time to choose, less stress, and a lower number of time-pressured offers. A large majority of residents (89%) prefer to submit a single application through a centralized system. The survey results suggest that residents who just completed the fellowship application process agree with the AAN recommended timeline for all subspecialties and that all neurology subspecialties should consider adopting a fellowship match. Programs can help facilitate a better fellowship application experience by providing earlier exposure to a broad range of neurologic subspecialties and ensure that residents are given opportunities to attend national meetings and participate in appropriately scoped scholarly endeavors.

Medical students need to understand core neuroscience principles as a foundation for their required clinical experiences in neurology. In fact, they need a solid neuroscience foundation for their clinical experiences in all other medical disciplines also because the nervous system plays such a critical role in the function of every organ system. Because of the rapid pace of neuroscience discoveries, it is unrealistic to expect students to master the entire field. It is also unnecessary, as students can expect to have ready access to electronic reference sources no matter where they practice. In the preclerkship phase of medical school, the focus should be on providing students with the foundational knowledge to use those resources effectively and interpret them correctly. This article describes an organizational framework for teaching the essential neuroscience background needed by all physicians. This is particularly germane at a time when many medical schools are reassessing traditional practices and instituting curricular changes such as competency-based approaches, earlier clinical immersion, and increased emphasis on active learning. This article reviews factors that should be considered when developing the preclerkship neuroscience curriculum, including goals and objectives for the curriculum, the general topics to include, teaching and assessment methodology, who should direct the course, and the areas of expertise of faculty who might be enlisted as teachers or content experts. These guidelines were developed by a work group of experienced educators appointed by the Undergraduate Education Subcommittee (UES) of the American Academy of Neurology (AAN). They were then successively reviewed, edited, and approved by the entire UES, the AAN Education Committee, and the AAN Board of Directors.

In this issue of Structural Heart, high-impact presentations from Transcatheter Valve Therapies 2023 are reviewed. Dr Jaffar Khan provided updates on the current understanding of left ventricular outflow tract obstruction in the field of transcatheter mitral valve replacement, highlighting known predictors of obstruction, a generally agreed-upon strategy for preprocedure assessment, and a host of management strategies in various stages of development and study.

An increasing number of surgically implanted bioprostheses will require re-intervention for structural valve deterioration. Valve-in-valve transcatheter aortic valve replacement (ViV TAVR) has become an alternative to reoperative surgery, currently approved for high-risk and inoperable patients. Challenges to the technique include higher rates of prosthesis–patient mismatch and coronary obstruction, compared to native valve TAVR. Herein, we review results of ViV TAVR and novel techniques to overcome the aforementioned challenges.

Transcatheter mitral valve replacement (TMVR) is a promising strategy for patients with mitral valve disease and no surgical options. Left ventricular outflow tract (LVOT) obstruction is a life-threatening complication of TMVR. Although there are no commercially available devices to prevent LVOT obstruction, the risk of it can be reduced by careful preprocedure planning and the use of novel modifications to commercially available devices. This article summarizes current techniques to prevent LVOT obstruction with an emphasis on electrosurgical strategies.

Transcatheter electrosurgery describes the ability to cut and traverse tissue, at a distance, without an open surgical field and is possible using either purpose-built or off-the-shelf devices. Tissue traversal requires focused delivery of radiofrequency energy to a guidewire tip. Initially employed to cross atretic pulmonary valves, tissue traversal has enabled transcaval aortic access, recanalization of arterial and venous occlusions, transseptal access, and many other techniques. To cut tissue, the selectively denuded inner curvature of a kinked guidewire (the Flying-V) or a single-loop snare is energized during traction. Adjunctive techniques may complement or enable contemporary transcatheter procedures, whereas myocardial slicing or excision of ectopic masses may offer definitive therapy. In this contemporary review we discuss the principles of transcatheter electrosurgery, and through exemplary clinical applications highlight the range of therapeutic options offered by this versatile family of procedures.

Left ventricular (LV) contractility and compliance are derived from pressure–volume (PV) loops during dynamic preload reduction, but reliable simultaneous measurements of pressure and volume are challenging with current technologies. We have developed a method to quantify contractility and compliance from PV loops during a dynamic preload reduction using simultaneous measurements of volume from real-time cardiovascular magnetic resonance (CMR) and invasive LV pressures with CMR-specific signal conditioning.

To investigate the performance of organic and inorganic phosphorous on growth of Roselle (Hibiscus sabdariffaL.), an experiment was carried out at Newly Developmental Farm (NDF), Horticulture Section, the university of Agriculture Peshawar, Pakistan, during 2012. The experiment was laid out in a Randomized Complete Block Design (RCBD) with split plot arrangement and replicated three times. The chemical fertilizer Single Super Phosphate (SSP) was used as inorganic source of phosphorus, while Organic Phosphate (OP) from organic product produced by Niha corporation containing 20% organic mineralized P2O5, was used as the source of organic phosphorous. Both the sources of fertilizer were applied at the rate of 10, 20, 30 40 and 50 kg · hm−2and control. The statistical analysis of data revealed that both the sources and levels of phosphorus significantly affected most of the growth parameters of Roselle except germination percentage and survival percentage. Plant height (112.09 cm), numbers of leave plant−1(177.87), numbers of branch plant−1(4.08), leaf areas (126.60 cm2), days to flowering (142.83), fresh flower weight (2.56 g), fresh calyx weight (1.70 g), dry calyx weight (0.43 g), numbers of calyces (94.10), numbers of root plant−1(11.03), root length (22.67 cm) and root weight (27.50 g) were observed in plants fertilized with organic source of phosphorous. Phosphorous levels significantly affected all of the parameters except germination percentage and survival percentage. The maximum plant height (124.39 cm), numbers of branches (5.32), numbers of leave plant−1(204.89), leaf areas (148.14 cm2), fresh flower weight (3.32 g), fresh calyx weight (2.04 g), dry calyx weight (0.51 g), numbers of calyces (105.30), numbers of root plant−1(12.78), root length (24.50 cm) and root weight (29.94 g) were observed in plants fertilized with 40 kg · hm−2phosphorous and the maximum numbers of days to flowering (148.17) were observed in the control plants. It was concluded from the experimental results that organic phosphorous at the rate 40 kg · hm−2would be used for better production of Roselle under agro-climatic condition of Peshawar.

Objective:We sought to better understand the potential impact of the burgeoning neurohospitalist model of inpatient care on education of neurology residents and to better define possible roles for “neurohospitalists” in residency education.Method:We designed a brief qualitative open-ended survey directed toward academic leaders in neurology and distributed it by e-mail to every academic neurology department in the United States and Canada.Results:Of 83 respondents, 36 (43%) had an active neurohospitalist program and only 10% felt certain they would not have 1 within the next 5 years. All respondents expected to have residents continue to be involved with inpatient care. The main perceived advantage for resident education associated with neurohospitalists was inpatient care expertise, and the main expected disadvantage was decreased exposure to subspecialty attendings. The majority anticipated positive impact on all Accreditation Council for Graduate Medical Education core competencies predominantly based on neurohospitalists’ expertise in the inpatient setting.Conclusion:The majority of academic neurology departments are expected to have a neurohospitalist program within the next 5 years. There are several perceived advantages and disadvantages to such a program for education of neurology residents. In general, the impact of these programs is expected to improve resident education. Regardless of expectations, neurohospitalists will likely play a prominent role in the education of the next generation of neurologists.

Pulmonary nocardiosis is a rare pulmonary infection with high morbidity and mortality. Limited real-world data on pulmonary nocardiosis patients are available from developing countries like Pakistan.

Introduction:The purpose of this study was to investigate the hemodynamic impact of LAMPOON (Laceration of the Anterior Mitral leaflet to Prevent Outflow ObstructioN) in transcatheter mitral valve replacement (TMVR) using patient-specific in silicomodeling.Methods:Eight subjects from the LAMPOON investigational device exemption trial were included. All subjects were at prohibitive risk of outflow tract obstruction from TMVR based on computed tomography (CT), and underwent successful LAMPOON immediately followed by TMVR. A validated computational fluid dynamics (CFD) model was used to compare simulated hemodynamics and 3D flow patterns between two modeled conditions: 1) TMVR with LAMPOON and 2) TMVR without LAMPOON. Using the post-procedure CT scans, anatomical models of TMVR with LAMPOON were created for each subject. The open transcatheter valve cells were then virtually closedto model TMVR without LAMPOON for each subject. Finally, CFD was performed for each condition to simulate the systolic flow fields.Results:As compared to TMVR without LAMPOON, TMVR with LAMPOON resulted in lower peak velocity, lower peak LVOT gradient, and higher peak LVOT effective orifice area by 13±6% (p=0.004), 28±14% (p=0.008), and 15±8% (p=0.002), respectively. LAMPOON provided flow communication through exposed cells of the transcatheter valve, thereby decreasing the flow constriction and reducing flow stasis in the vicinity of the neo-LVOT (Figure). The hemodynamic benefit of LAMPOON was observed to be greater in subjects with a smaller neo-LVOT area measured post-implant (p<0.001).Conclusions:In silicomodeling allowed for a quantitative patient-specific comparison of TMVR with and without LAMPOON, which is impossible to study clinically. The LAMPOON procedure improved simulated hemodynamics in all subjects, with a greater hemodynamic impact observed in subjects with a smaller post-implant neo-LVOT area.

Central and peripheral nervous system dysfunction is common in the setting of critical medical illness. An approach to neurologic diagnosis in the medical intensive care unit (MICU) requires a familiarity with current critical care practice. Common reasons for neurologic consultation in an MICU setting include disorders of consciousness, seizures, and generalized weakness. Focused approaches to these entities in the MICU will be reviewed in this chapter, with emphasis on frequency and etiology. It is increasingly recognized that neurologic dysfunction in the MICU population is common, impacts morbidity, and impairs outcome.

To characterize the prevalence, time of onset, and cause of neuromuscular dysfunction in patients with severe sepsis.

The kinetics of electron transfer from cyclic ketones (represented by (S)) to Ni(IV) periodate complexes has been studied in aqueous alkaline medium. The kinetics exhibit a pseudo-first-order disappearance of Ni(IV) periodate complexes when the [substrate] is present in excess. The pseudo-first-order rate constants, kobs, were linearly dependent on [S] and the order in [S] were found to be unity. The rate of the reaction increased with the increase in [OH−], however the rates were retarded with the increase in [periodate]. Salt and solvent effect studies indicate that the reaction is of ion-dipole type. A suitable mechanism involving slow adduct formation between enol and oxidant, and its decomposition in a fast step have been suggested. A rate law consistent with the proposed mechanism has also been derived. The products of oxidation were identified as corresponding decarboxylic acids.

All bioprosthetic valves, both surgical and transcatheter, have a finite lifespan before their leaflets inevitably degenerate, leading to stenosis or regurgitation. As younger, low risk patients receive a transcatheter aortic valve, it is expected that they will most likely outlive their bioprosthetic valve. The heterogeneity of studies regarding surgical valve durability make the interpretation of the data challenging. Leaflet thickening is seen in transcatheter heart valves but currently there is no evidence that it leads to premature valve deterioration or clinical events. Standardized definitions of structural valve deterioration should allow for comparisons between future clinical trials to assess durability of different transcatheter heart valves.

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BackgroundLeft ventricular outflow tract (LVOT) obstruction is a life-threatening complication of transcatheter mitral valve implantation (TMVI), caused by septal displacement of the anterior mitral leaflet (AML). We used a new catheter technique to split the AML.MethodsEighteen patients with severe mitral valve disease, prior surgical ring or mitral annular calcification, and prohibitive surgical risk were offered LAMPOON and TMVI on a compassionate basis. Iatrogenic LVOT obstruction was predicted in all based on echocardiography and CT.Transfemoral guiding catheters directed an electrified guidewire across the AML towards a snare in the left atrium. The externalised guidewire loop was electrified to lacerate the AML along the centreline from base to tip, sparing chordae, immediately before transseptal TMVI (figure 1).[Figure]ResultsAll patients had successful laceration of the AML. Following TMVI, the transcatheter heart valves spanned the LVOT but with Doppler flow through the open cells. In one patient, the valve missed the anterior landing zone and deployed into the LVOT, causing obstruction despite LAMPOON. All other patients had no or tolerable gradients.ConclusionsThis novel catheter technique, which resembles surgical chord-sparing AML resection, may enable TMVI in patients with prohibitive risk of LVOT obstruction. An early feasibility trial of LAMPOON is underway in the United States.

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