Impact of transcatheter heart valve type on outcomes of surgical explantation after failed transcatheter aortic valve replacement: the EXPLANT-TAVR international registry.

BACKGROUND: There are limited data on the impact of transcatheter heart valve (THV) type on the outcomes of surgical explantation after THV failure. AIMS: We sought to determine the outcomes of transcatheter aortic valve replacement (TAVR) explantation for failed balloon-expandable valves (BEV) versus self-expanding valves (SEV). METHODS: From November 2009 to February 2022, 401 patients across 42 centres in the EXPLANT-TAVR registry underwent TAVR explantation during a separate admission from the initial TAVR. Mechanically expandable valves (N=10, 2.5%) were excluded. The outcomes of TAVR explantation were compared for 202 (51.7%) failed BEV and 189 (48.3%) failed SEV. RESULTS: Among 391 patients analysed (mean age: 73.0±9.8 years; 33.8% female), the median time from index TAVR to TAVR explantation was 13.3 months (interquartile range 5.1-34.8), with no differences between groups. Indications for TAVR explantation included endocarditis (36.0% failed SEV vs 55.4% failed BEV; p<0.001), paravalvular leak (21.2% vs 11.9%; p=0.014), structural valve deterioration (30.2% vs 21.8%; p=0.065) and prosthesis-patient mismatch (8.5% vs 10.4%; p=0.61). The SEV group trended fewer urgent/emergency surgeries (52.0% vs 62.3%; p=0.057) and more root replacement (15.3% vs 7.4%; p=0.016). Concomitant cardiac procedures were performed in 57.8% of patients, including coronary artery bypass graft (24.8%), and mitral (38.9%) and tricuspid (14.6%) valve surgery, with no differences between groups. In-hospital, 30-day, and 1-year mortality and stroke rates were similar between groups (allp>0.05), with no differences in cumulative mortality at 3 years (log-rank p=0.95). On multivariable analysis, concomitant mitral surgery was an independent predictor of 1-year mortality after BEV explant (hazard ratio [HR] 2.00, 95% confidence interval [CI]: 1.07-3.72) and SEV explant (HR 2.00, 95% CI: 1.08-3.69). CONCLUSIONS: In the EXPLANT-TAVR global registry, BEV and SEV groups had different indications for surgical explantation, with more root replacements in SEV failure, but no differences in midterm mortality and morbidities. Further refinement of TAVR explantation techniques are important to improving outcomes.

Visualizing Inside Conduits-Intraoperative Screening of Grafts by Optical Coherence Tomography.

PURPOSE: Saphenous vein graft (SVG) failure is a complex phenomenon, with technical, biologic, and local factors contributing to early and medium- and long-term failure after coronary artery bypass graft. Both technical and conduit factors may have significant impact on early SVG failure. DESCRIPTION: We review the complex factors that play a pathogenic role in SVG failure, followed by review of the existing literature on potential utility of high-definition optical coherence tomography (OCT) in comprehensive intraoperative assessment of SVGs. EVALUATION: We describe a new technique for intraoperative acquisition of OCT images in the harvested SVGs and introduce a classification system for pathologic processes that can be detected in the harvested SVG conduits by OCT. CONCLUSIONS: The potential impact on early graft failure of the exclusion of segments of SVGs that are less than optimal (ie, containing fibroatheroma, retained thrombus, sclerotic valves, or procurement injury) will be examined in the randomized controlled OCTOCAB (Intraoperative Optical Coherence Tomography of the Saphenous Vein Conduit in Patients Undergoing Coronary Artery Bypass Surgery) trial.

Mitral Valve Surgery After Transcatheter Edge-to-Edge Repair: Mid-Term Outcomes From the CUTTING-EDGE International Registry.

OBJECTIVES: The aim of this study was to determine clinical and echocardiographic characteristics, mechanisms of failure, and outcomes of mitral valve (MV) surgery after transcatheter edge-to-edge repair (TEER). BACKGROUND: Although >100,000 mitral TEER procedures have been performed worldwide, longitudinal data on MV surgery after TEER are lacking. METHODS: Data from the multicenter, international CUTTING-EDGE registry were retrospectively analyzed. Clinical and echocardiographic outcomes were evaluated. Median follow-up duration was 9.0 months (interquartile range [IQR]: 1.2-25.7 months) after MV surgery, and follow-up was 96.1% complete at 30 days and 81.1% complete at 1 year. RESULTS: From July 2009 to July 2020, 332 patients across 34 centers underwent MV surgery after TEER. The mean age was 73.8 ± 10.1 years, median Society of Thoracic Surgeons risk for MV repair at initial TEER was 4.0 (IQR: 2.3-7.3), and primary/mixed and secondary mitral regurgitation were present in 59.0% and 38.5%, respectively. The median interval from TEER to surgery was 3.5 months (IQR: 0.5-11.9 months), with overall median Society of Thoracic Surgeons risk of 4.8% for MV replacement (IQR: 2.8%-8.4%). The primary indication for surgery was recurrent mitral regurgitation (33.5%), and MV replacement and concomitant tricuspid surgery were performed in 92.5% and 42.2% of patients, respectively. The 30-day and 1-year mortality rates were 16.6% and 31.3%, respectively. On Kaplan-Meier analysis, the actuarial estimates of mortality were 24.1% at 1 year and 31.7% at 3 years after MV surgery. CONCLUSIONS: In this first report of the CUTTING-EDGE registry, the mortality and morbidity risks of MV surgery after TEER were not negligible, and only <10% of patients underwent MV repair. These registry data provide valuable insights for further research to improve these outcomes.

On the interpretation of likelihood ratios in forensic science evidence: Presentation formats and the weak evidence effect.

Likelihood ratios are increasingly being adopted to convey expert evaluative opinions to courts. In the absence of appropriate databases, many of these likelihood ratios will include verbal rather than numerical estimates of the support offered by the analysis. However evidence suggests that verbal formulations of uncertainty are a less effective form of communication than equivalent numerical formulations. Moreover, when evidence strength is low a misinterpretation of the valence of the evidence - a "weak evidence effect" - has been found. We report the results of an experiment involving N=404 (student and online) participants who read a brief summary of a burglary trial containing expert testimony. The expert evidence was varied across conditions in terms of evidence strength (low or high) and presentation method (numerical, verbal, table or visual scale). Results suggest that of these presentation methods, numerical expressions produce belief-change and implicit likelihood ratios which were most commensurate with those intended by the expert and most resistant to the weak evidence effect. These findings raise questions about the extent to which low strength verbal evaluative opinions can be effectively communicated to decision makers at trial.

Mycophenolate mofetil-induced erythroid hypoplasia in a patient with systemic lupus erythematosus.

Anaemia is prevalent in patients with systemic lupus erythematosus (SLE). The anaemia is often a consequence of the disease itself but may also be secondary to drug treatments. Mycophenolate mofetil (MMF) is increasingly used in the management of patients with SLE and its associated anaemia. We describe the case of a 19-year-old girl, who presented acutely with SLE and renal involvement. Her disease was controlled with immunosuppression but she later developed severe transfusion-dependent anaemia. Several causes were considered before a bone marrow biopsy led to the diagnosis of erythroid hypoplasia. In the absence of clinical or laboratory markers of active lupus, MMF was implicated as the cause. Its discontinuation led to a rapid and sustained correction of the anaemia. Red cell aplasia linked to the use of MMF is uncommon and the manufacturers are aware of fewer than 50 cases. This is the first case report of evolving red cell aplasia induced by MMF in SLE.

A prospective study of PHACE syndrome in infantile hemangiomas: demographic features, clinical findings, and complications.

PHACE (OMIM no. 606519) is a neurocutaneous syndrome that refers to the association of large, plaque-like, "segmental" hemangiomas of the face, with one or more of the following anomalies: posterior fossa brain malformations, arterial cerebrovascular anomalies, cardiovascular anomalies, eye anomalies, and ventral developmental defects, specifically sternal defects and/or supraumbilical raphe. The etiology and pathogenesis of PHACE is unknown, and potential risk factors for the syndrome have not been systematically studied. The purpose of this study was thus to determine (1) the incidence of PHACE and associated anomalies among a large cohort of hemangioma patients, (2) whether certain demographic, prenatal or perinatal risk factors predispose infants to this syndrome, and (3) whether the cutaneous distribution of the hemangioma can be correlated to the types of anomalies present. We undertook a prospective, cohort study of 1,096 children with hemangiomas, 25 of whom met criteria for PHACE. These 25 patients represented 20% of infants with segmental facial hemangiomas. Compared to previous reports, our PHACE patients had a higher incidence of cerebrovascular and cardiovascular anomalies. Two developed acute arterial ischemic stroke during infancy, while two with cardiovascular anomalies showed documented evidence of normalization, suggesting that both progressive and regressive vascular phenomena may occur in this syndrome. Correlation to the anatomic location of the hemangioma appears to be helpful in determining which structural abnormalities might be present. A comparison of demographic and perinatal data between our PHACE cases and the hemangioma cohort overall showed no major differences, except a trend for PHACE infants to be of slighter higher gestational age and born to slightly older mothers. Eighty-eight percent were female, a finding which has been noted in multiple other reports. Further research is needed to determine possible etiologies, optimal evaluation, and outcomes.

Perceptual and physiological responses to the visual complexity of fractal patterns.

Fractals have experienced considerable success in quantifying the complex structure exhibited by many natural patterns and have captured the imagination of scientists and artists alike. With ever widening appeal, they have been referred to both as "fingerprints of nature" and "the new aesthetics." Our research has shown that the drip patterns of the American abstract painter Jackson Pollock are fractal. In this paper, we consider the implications of this discovery. We first present an overview of our research from the past five years to establish a context for our current investigations of human response to fractals. We discuss results showing that fractal images generated by mathematical, natural and human processes possess a shared aesthetic quality based on visual complexity. In particular, participants in visual perception tests display a preference for fractals with mid-range fractal dimensions. We also present recent preliminary work based on skin conductance measurements that indicate that these mid-range fractals also affect the observer's physiological condition and discuss future directions based on these results.

The microanatomic location of metastatic melanoma in sentinel lymph nodes predicts nonsentinel lymph node involvement.

PURPOSE: Sentinel node biopsy is now widely accepted as the most accurate prognostic indicator in melanoma, and is important in guiding management of patients with clinical stage I or II disease. Patients with a positive sentinel node have conventionally undergone completion lymphadenectomy (CLND) of the involved basin, but only 20% have involvement beyond the sentinel node, suggesting that CLND may be unnecessary for the other 80% of patients. This study seeks to identify criteria that might be used to be more restrictive in selecting those who should undergo CLND. METHODS: A total of 146 patients were identified who had had a positive sentinel node biopsy for malignant melanoma. Their sentinel nodes and lymphadenectomy specimens were re-evaluated pathologically. The metastatic melanoma in each sentinel node was assessed according to its microanatomic location within the node (subcapsular, combined subcapsular and parenchymal, parenchymal, multifocal, or extensive), and this was correlated with the presence of involved nonsentinel nodes in the CLND. The depth of the metastases from the sentinel node capsule was also recorded. RESULTS: The metastatic deposits in the sentinel node were subcapsular in 26.0% of patients. None of these patients had any nonsentinel nodes involved on CLND. In the patients whose sentinel node metastases had a different microanatomic location, the rate of nonsentinel node involvement was 22.2% overall. CONCLUSION: The microanatomic location of metastases within sentinel nodes predicts nonsentinel lymph node involvement. In patients with only subcapsular deposits in the sentinel node, it is possible that CLND could safely be avoided.

The C-neu mammary carcinoma in Oncomice; characterization and monitoring response to treatment with herceptin by magnetic resonance methods.

To characterize spontaneously occurring c-neu/HER2 overexpressing tumours in oncomice and their response to herceptin by non-invasive magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI). Oncomice were monitored by localized 31P MRS during unperturbed growth and before and after treatment with 10 mg/kg herceptin (Hoffman La Roche) intraperitoneally for up to 21 days post-treatment. Vascular morphology and function was assessed by quantitation of tumour magnetic resonance (MR) relaxation rates R2* and R2 prior to and either during carbogen (95% O2/5% CO2) breathing or following administration of the blood-pool contrast agent NC100150 (Clariscan, Amersham Health). Immunohistochemistry showed strong membrane staining for HER2 protein overexpression. The 31P MRS showed only a significant (p<0.01) increase of phosphomonoester / total phosphate ratio over 21 days of growth. Herceptin increased the tumour volume doubling time compared to untreated tumours and significantly increased the phosphomonoester / beta-nucleoside triphosphate ratio 2 days after treatment (p=0.01). Tumours showed a highly heterogeneous yet significant (p<0.01) decrease or increase in R2* in response to carbogen or NC100150 respectively. The absence of a decline in tumour bioenergetics with growth, commonly seen in 31P MRS studies of transplanted rodent tumour models, coupled with the heterogeneous blood volume revealed by 1H MRI, suggest a metabolic and vascular phenotype similar to that found in human tumours.

Application of information technology to decision support in treatment plant operation.

This paper reviews decision support methodologies that can be applied to treatment plants. Case studies of decision support systems (DSS) that have been developed and used or trialled are presented below. These include rule-based systems and systems based on digraphs of cause-and-effect relationships. Detection examples on real plant data are presented, in one case using direct measurements and simple detectors and in another using multivariate statistics and clustering.

Comparison of the microvasculature of basal cell carcinoma and actinic keratosis using intravital microscopy and immunohistochemistry.

BACKGROUND: Angiogenesis is a prerequisite for growth of invasive tumours. We hypothesized that angiogenesis would be present in invasive basal cell carcinoma (BCC) but not in a noninvasive tumour such as actinic keratosis (AK). OBJECTIVES: To investigate both types of tumour for evidence of angiogenesis. METHODS: Patients with BCC or AK underwent intravital videocapillaroscopy. Three regions were examined: the tumour, perilesional skin and a control site. Microvessel width, area fraction and length density were determined from capillaroscopy images. Biopsies were stained for CD34 and a microvessel count was performed. RESULTS: Capillaroscopy demonstrated a grossly disorganized tumour microcirculation in BCC. Compared with control skin, microvessel width was increased 2.4-fold, area fraction was increased 4.9-fold and length density was increased 5.9-fold. In AK, microvessel width was increased 1.7-fold, area fraction 2.5-fold and length density 3.4-fold. Vessel width and area fraction were significantly greater in BCC than AK. Biopsies showed significant increases in microvessel length density for both BCC and AK compared with control skin, with BCC significantly greater than AK. CONCLUSIONS: Angiogenesis was demonstrated in BCC in humans in vivo, and to a lesser extent in AK.

The relationship between the structural mere exposure effect and the implicit learning process.

Three experiments are reported that investigate the relationship between the structural mere exposure effect (SMEE) and implicit learning in an artificial grammar task. Subjects were presented with stimuli generated from a finite-state grammar and were asked to memorize them. In a subsequent test phase subjects were required first to rate how much they liked novel items, and second whether or not they thought items conformed to the rules of the grammar. A small but consistent effect of grammaticality was found on subjects' liking ratings (a "structural mere exposure effect") in all three experiments, but only when encoding and testing conditions were consistent. A change in the surface representation of stimuli between encoding and test (Experiment 1), memorizing fragments of items and being tested on whole items (Experiment 2), and a mismatch of processing operations between encoding and test (Experiment 3) all removed the SMEE. In contrast, the effect of grammaticality on rule judgements remained intact in the face of all three manipulations. It is suggested that rule judgements reflect attempts to explicitly recall information about training items, whereas the SMEE can be explained in terms of an attribution of processing fluency.

MRI lesion volume measurement in multiple sclerosis and its correlation with disability: a comparison of fast fluid attenuated inversion recovery (fFLAIR) and spin echo sequences.

OBJECTIVES: To assess whether multiple sclerosis lesion volume measurements derived using the fast fluid attenuated inversion recovery (fFLAIR) sequence show better reproducibility or correlation with disability than those derived using the conventional spin echo (CSE) sequence. METHODS: Part I: twenty five patients with multiple sclerosis were scanned with CSE, fast spin echo (FSE), and fFLAIR. Lesion volume was determined twice for each sequence using a local threshold segmentation technique. Part II: fifty six patients with multiple sclerosis were scanned with CSE and fFLAIR. Total and regional brain lesion volumes were compared with the Kurtzke extended disability scale (EDSS) and functional systems scores (FSS). RESULTS: Part I: analysis times were significantly longer for CSE than for FSE or fFLAIR. There was no significant difference in the reproducibility of the three sequences. Part II: total lesion volumes were similar but posterior fossa lesion volumes were significantly greater for CSE and subcortical lesion volumes significantly greater for fFLAIR. There was a significant correlation between total volume and EDSS with both sequences (CSE r=0.49; fFLAIR r=0.44). Correlations for the two sequences showed minor differences when anatomical region and FSS were considered separately. CONCLUSIONS: CSE, FSE, and fFLAIR are equally reproducible; FSE yields lower volumes than CSE; fFLAIR gives similar volumes to CSE but underscores the posterior fossa. Overall clinical correlations are similar for CSE and fFLAIR.

Barium ions fail to support neurotransmission at a central synapse.

Synaptic transmission in the CA1 area of the hippocampal slice preparation in vitro was studied in bathing media containing different levels of divalent cations. Transmission was abolished by replacing the normal levels (2.5 mM) of Ca2+ with 3 mM Mg. Transmission was not permanently restored by subsequent addition of Ba2+ but added Ca2+ was effective. Transient reappearance of synaptic currents were seen when Ba2+ was added at a time when contaminating levels of Ca2+ were still present, but neurotransmission waned as [Ca2+]e declined with protracted washout. In accordance with this interpretation, Ba2+ potentiated the transmission observed in the presence of low concentrations (0.25 mM) of Ca2+. Little evidence was found for Ba2+ effects at axonal sites but the potentiation of synaptic transmission by Ba2+ could be accounted for in terms of a blockade of terminal K-channels.