417 Can myocardial stiffness measurements distinguish the underlying pathology in hearts with thick walls? A shear wave imaging study using ultra-high frame rate echocardiography

Background

Different pathophysiologic pathways in the development of left ventricular (LV) hypertrophy may alter passive myocardial stiffness differently. Recently, cardiac shear wave (SW) elastography has been proposed as new non-invasive technique for assessing myocardial stiffness.

Purpose

To explore the relationship between myocardial stiffness and the underlying pathological substrates for cardiac hypertrophy.

Methods

We included 17 patients with cardiac amyloidosis (AML) (69 ± 10 years, 41% male), 17 patients with hypertrophic cardiomyopathy (HCM) (59 ± 16 years, 65% male) matched for interventricular septum (IVS) thickness and 17 hypertensive patients (HT) with prominent myocardial remodelling (56 ± 15 years, 71% male). LV parasternal long axis views were acquired with an experimental ultrasound scanner at 1255 ± 354 frames per seconds. Myocardial acceleration maps were created from the HFR-datasets and an anatomical M-mode line was drawn along the midline of the IVS (Figure A). The propagation velocity of natural SWs occurring at mitral valve closure (MVC) was measured on these M-modes in order to assess operating myocardial stiffness. To compare myocardial stiffness among hearts with differing loading conditions and chamber geometry, SW velocities were normalized to operating end-diastolic wall stress. The end-diastolic wall stress was estimated at the IVS from regional wall thickness, longitudinal and circumferential regional radii of curvature, and noninvasively estimated left ventricular end-diastolic pressure (EDP).

Results

IVS thickness was significant different among groups (AML: 1.63 ± 0.33 cm, HCM: 1.69 ± 0.21 cm, HT: 1.48 ± 0.14 cm; p = 0.037). HT patients had significant higher septal radius of curvature compared to other two groups (p < 0.05), while the AML patients had the highest estimated EDP (p < 0.05). All groups had comparable, elevated SW velocities at MVC (AML: 6.49 ± 1.00 m/s, HCM: 6.46 ± 1.45 m/s, HT: 6.22 ± 0.96 m/s; p = 0.752). Considering end-diastolic wall stress, HT patients had the same SW velocity at higher wall stress compared to AML and HCM (Figure B), indicating lower myocardial stiffness in the HT group. SW velocities normalized for wall stress indicated significantly different myocardial stiffness among groups (p = 0.003) (Figure C). The HT group had the lowest normalized myocardial stiffness, whereas values of the AML group overlapped with the HCM group (p = 1.00).

Conclusions

Our study demonstrated that shear wave elastography can detect differences in myocardial stiffness in hearts with thick walls. Considering the effect of wall stress, our results suggest that factors other than chamber geometry and loading condition mediate myocardial stiffness in hearts with thick walls. We hypothesize that differential changes in cardiomyocytes and/or the extracellular matrix contribute to the differential myocardial stiffening in different pathologic entities of LV hypertrophy.

Abstract 417 Figure.

Does wild rabbit population size affect connectivity?

<p>Wild rabbit is a relevant species in the Iberian Peninsula due to its ecological  and economic roles. Conservationists and game managers therefore have a shared interest in assuring the existence of resilient and sustainable populations. Although management principles and guidelines are  mostly known and understood, often the results are not as good as expected. Local abundance can vary significantly even in short periods, while the colonisation of adjacent territories is uncommon, probably due to the territorial behaviour of the species. Aware that the foundation of nuclei requires interaction among individuals, we hypothesised that rabbit abundance plays a significant part in population connectivity. In order to find out whether the population size affects nuclei connectivity, we conducted a graph theory-based connectivity analysis. The results confirm that connectivity grows with rabbit abundance, but only to a certain degree, and there is a spatial separation of the nuclei regardless of the population size. These outcomes suggest that a comprehensive wild rabbit population increment plan should address both the abundance and spatial distribution, but should not aim at achieving a continuous distribution of wild rabbit with constant or similar abundance. Regarding specific management actions, we argue that in restocking operations new nuclei should be located within dispersal range from the existing ones to promote inter-nuclei connectivity, but not too close, as the nuclei segregation tendency is likely to persist due to the species’ territoriality.</p>

Methods of Tracking Newborns: New York State Zika Pregnancy and Infant Registry, 2015-2017

Objectives. To describe methods employed to track infants enrolled in the New York State Zika Pregnancy and Infant Registry (NYSZPIR) and demonstrate the benefits of population databases to improve the process.Methods. We used patient medical records and provider outreach, New York State Immunization Information System (NYSIIS), and New York State Early Hearing Detection and Intervention Information System (NYEHDI-IS) to gather medical information. We used descriptive statistics to summarize variables and the McNemar test to determine statistical significance (P < .05).Results. We identified 109 live births from NYSZPIR mothers. Provider information was documented for 106 (97.2%) infants in NYSIIS compared with 72 (66.1%) through chart review. Collected results of newborn hearing screening increased from 82 (75.2%) to 106 (97.2%) using NYEHDI-IS. The amount of data obtained was significantly higher (P < .001) when including NYSIIS and NYEHDI-IS compared with using medical records alone.Conclusions. Public health surveillance systems can be used to track infants using data sources such as NYSIIS and NYEHDI-IS in addition to traditional methods. Using medical records alone is inadequate for locating and tracking infants and may result in high lost to follow-up rates.

Factors affecting space use by wild boars (Sus scrofa) in high-elevation tropical forests

The wild boar (Sus scrofa Linnaeus, 1758) is considered one of the 100 worst invasive species in the world and is present in the high-elevation forests in Brazil. Our objective was to understand how landscape and atmospheric conditions affect space use by wild boars. We hypothesized that wild boars would be more frequent at lower elevations, warmer and wetter forested areas, and away from human disturbances. After three years of data collection (2013–2016) using 16 camera traps, 881 independent records were obtained with a mean of 4.44 ± 9.25 pigs per record. Wild boar frequency of occurrence was higher at lower elevations, in more humid and warmer areas, and farther away human disturbance factors, corroborating our initial hypothesis. Understanding space-use patterns of wild boars is necessary for the design of management strategies that target areas of more intense usage, as well as for defining more effective population-control techniques.

P975Safety and clinical outcomes of rotational atherectomy: an eleven-year centre experience

Introduction

Rotational atherectomy (RA) is an adjunctive tool for the management of heavily calcified coronary lesions during percutaneous coronary intervention (PCI), but the clinical outcomes remain unclear. Access site choice is also poorly defined and there is growing evidence that transradial approach (TRA) is associated with lower complications and lower mortality.

Objectives

To assess the safety and long-term outcomes of RA for calcified coronary lesions and to investigate the influence of vascular access site in the efficacy and safety of the procedure.

Methods

Retrospective single-centre study that included consecutive PCI with RA performed from January 2006 to December 2017. Endpoint was a composite of major adverse cardiac events (MACE), defined as cardiovascular death, nonfatal myocardial infarction, nonfatal stroke and target vessel revascularization, at 1- and 5-year.

Results

246 procedures were included in a total of 236 patients (pts): mean age 70.1±9.7 years, 73.6% male; 36.2% had previous PCI, 12.2% vascular peripheral disease (VPD), 24% reduced left ventricle ejection fraction (LVEF) and 6.9% were under hemodialysis. PCI with RA was mostly performed due to stable angina (48.9%) and via TRA (55.3%), with a total of 371 treated segments and a median number of 1 vessel treated per intervention. The left anterior descending artery was the most frequently treated artery (67.5%). Single burr was used in 76% of cases (mean number of burrs 1.23; mean burr size 1.5 mm). Procedural success rate was 94.7%. Complications were recorded in 9.3%, with no procedure related death. Clinical follow-up was complete in 98.8% of pts at 1-year and 81.3% at 5-year (mean time 62.3±41.8 months). Survival free of MACE at 1- and 5-year were 83.7% and 73.2%, respectively. Multivariate Cox regression identified 6 independent predictors (only 1 protector) for 1-year MACE (Fig. A) and 6 independent predictors (all of increased risk) for 5-year MACE (Fig. B). TRA was protector of 1-year MACE and Kaplan-Meier curves showed benefit for both 1- and 5-year MACE occurrence (Fig. C and D), without significant difference in procedural success (p=0.92) and complications (p=0.45) rate comparing to transfemoral approach.

Conclusions

RA followed by stenting was a safe procedure with a high immediate success rate but an increased number of long-term cardiovascular events. Some clinical conditions, such as previous PCI, VPD and reduced LVEF, seems to adversely influence the long-term outcome while TRA appears to be protective.

P1501Can we measure the stiffening of hypertensive hearts non-invasively? A shear wave imaging study using ultra-high frame rate echocardiography

Background

Cardiac shear wave (SW) elastography is a novel technique based on high-frame-rate (HFR) echocardiography which has been shown to be related to myocardial stiffness. In this study we explore the relation between myocardial SW velocity and myocardial remodelling in remodelled hearts of patients with arterial hypertension (AH).

Methods

We prospectively included 33 treated AH patients with hypertrophic left ventricular (LV) remodelling (59±14 years, 55% male) and 26 aged matched healthy controls (55±15 years, 77% male). AH patients were further divided according to their LV geometric pattern into a concentric remodelling (CR) group (13 patients) and a concentric hypertrophy (CH) group (20 patients). LV parasternal long axis views were acquired with an experimental HFR ultrasound scanner (HD-PULSE) at 1266±317 frames per seconds. Myocardial acceleration maps were created from the HFR-datasets and an anatomical M-mode line was drawn along the midline of the interventricular septum (IVS). The propagation velocity of natural SWs occurring at mitral valve closure (MVC) was measured on these M-modes (Figure A) in order to assess passive myocardial stiffness. Standard echocardiography using a commercial scanner was performed to evaluate LV remodelling.

Results

SW velocities at MVC differed significantly between AH patients and controls (5.83±1.20 m/s vs. 4.04±0.96 m/s; p<0.001). Within the patient group, patients with CH had highest SW velocities at MVC (p<0.001), whereas values between controls and patients with CR were comparable (p=0.075) (Figure B). In AH patients, significant positive correlations were found between SW velocity at MVC and parameters of LV remodelling (IVS thickness: r=0.728, p<0.001; LV mass index: r=0.780, p<0.001, LV end-diastolic volume: r=0.604, p=0.008) (Figure C) and also parameters of diastolic function (E/e': r=0.495, p=0.005, left atrium diameter: r=0.866, p<0.001, left atrium volume index: r=0.661, p<0.001).

Figure A, B, C

Conclusions

SW velocity – and therefore myocardial stiffness – is higher in AH patients compared to healthy controls and increases with increasing severity of hypertensive heart disease. Patients with concentric remodelling have still close-to-normal passive myocardial properties while patients with concentric hypertrophy show significant stiffening. Echocardiographic shear wave elastography is a promising new technique for the non-invasive assessment of myocardial stiffness and might provide valuable new insights into myocardial function and the pathophysiology of myocardial disease.

Influence of yeasts of the genus Saccharomyces and not Saccharomyces in elaboration of white wines

Traditionally the Serra Gaúcha region, in the state of Rio Grande do Sul, is known as a barn productor of excellent quality wines. The aromatic complexity of wine in general, and white wine in particular, is what is essential to satisfy an increasingly demanding consumer. Among the most used techniques to achieve this purpose is the addition of yeasts of different genres, thus providing a range of aromatic characteristics that are accentuated in it. In this sense, the objective of this work was to evaluate the use of different strains of yeasts in white wines of Riesling Italic variety, made from grapes grown in the Serra Gaúcha region, in the state of Rio Grande do Sul. Based on the results, it was possible to observe that there were no significant differences between the treatments in relation to the variables pH, total acidity and alcoholic degree. However, with respect to the fermentation yield, T3 was the treatment that obtained the best performance, reaching the ideal density (below 1000 g.cm3) in the course of 6 to 7 days, followed by treatments T1 (Saccharomyces cerevisae) and T5 (Levulia pulcherrima) (7 to 8 days), with treatments T2 (Saccharomyces cerevisaecerevisae) and T4 (Torulaspora delbrueckii), which had the lowest performance (9 to 10 days). The T4 treatment was also the one that presented a higher amount of residual sugars, which proves the less activity of this yeast in more alcoholic means. All the yeasts used have a low production of volatile acidity, but the lowest concentration was Saccharomyces cerevisae cerevisae, used in treatment T2 (0.1 gL−1), and the other treatments presented higher concentrations (0, 4 to 0.5 gL−1), although it is still within the parameters considered ideal for obtaining quality white wines. T2 was also the treatment with lower concentrations of glycerol (5.1 g.L−1). This compound is mainly formed by glyceropyruvic fermentation through the metabolism of yeasts at the beginning of alcoholic fermentation, usually being produced by the first 50 grams of fermented sugars, which may indicate a greater activity of this yeast in this fermentation period. In general, we can say that all the yeasts used have the potential to produce quality white wines, since they had good fermentation yields, satisfactory production of alcohol and glycerol, and low production of volatile acidity.

Scalp porocarcinoma and lichen planopilaris

Porocarcinoma (PC) is a malignant neoplasm arising from the intraepidermal ductal portion of the sweat gland duct. Lichen planopilaris (LPP) is a not so rare variant of cutaneous lichen planus (LP) with a preferential involvement of hair follicles, consisting of a chronic lymphocytic inflammation, leading to cicatricial alopecia. A 42-year-old woman, recently diagnosed with HIV infection, was referred to our clinic because of an alopecic patch of 6 years' duration. In the upper region of the alopecia a 1.5cm nodule was noticed, which the patient stated had started growing soon after the appearance of the hair loss. Biopsy of the alopecia margin confirmed the diagnosis of LPP, whereas biopsy of the nodule revealed an infiltrating tumor consistent with the diagnosis of PC. We present a scalp PC emerging in a background of LPP in an HIV patient. We do not know the role, if any, HIV infection and LPP played in this particular case. Immunosuppression and HIV have been implicated in the etiology of PC. However, her HIV diagnosis was made after the appearance of the scalp nodule. We did not find any association between LPP and PC in the literature. Even though an association by chance cannot be excluded, this deserves further investigation.

Wild rabbit restocking: Suitable acclimation conditions foster adaptive behaviour and improve survival of captive reared rabbits

Wild rabbit is a very important species in the Mediterranean region. Its relevance is both ecological, being a keystone species —prey for several predators— and economic, as it is the most important and the most managed small game species among mammals in the Iberian Peninsula. Although both researchers and game managers claim restocking operations have moderate to low success, it is still one of the management measures often used by conservationists and hunters to recover or boost wild rabbit populations. The high mortality usually verified in the first days after release is the main limiting factor in rabbit restocking. Based on practical research, protocols have improved, pointing out good practices and suggestions to increase success. Adopting soft instead of hard-release protocols has been proven to increase short-term survival after liberation. Aware that purchased rabbits seldom display a quick adaptation to the field, we performed two restocking experiments with different conditions (acclimation period and park size) in order to compare the outcomes in terms of survival rate. The rabbit batch that experienced a longer acclimation period in a larger park showed higher survival rates, as well as more frequent and much larger spatial movements. These results suggest that proper conditions during acclimation may contribute to the success of wild rabbit restocking operations.

Infection of the muscle tissue of the filter-feeding cichlid, Chaetobranchopsis orbicularis Steindachner, 1875, by Kudoa orbicularis (Myxozoa: Multivalvulidae) on Marajó Island in the Brazilian Amazon region

ABSTRACT This study describes aspects of infections caused by the myxosporidian Kudoa orbicularis in filter-feeding cichlids, Chaetobranchopsis orbicularis, caught in the Arari River in the municipality of Cachoeira do Arari, on Marajó Island, Pará, Brazil. The parasite forms pseudocysts scattered throughout the striated epaxial and hypaxial muscles. Samples embedded in paraffin were analyzed histologically using hematoxylin-eosin, Gömöri, Ziehl-Neelsen, and Giemsa staining. Necropsy of the C. orbicularis specimens revealed that 100% (50/50) were infected with K. orbicularis. The specimens presented grossly abnormal muscle texture, resulting in extensive inconsistencies and weakness. Progressive softening of the muscles was observed during necropsy, indicating the rapid enzymatic autolysis of the tissue. The parasite found in the muscle tissue of C. orbicularis was identified as K. orbicularis, with clinical signs of disease being observed in the fish. The necropsy revealed extensive damage to the host organism, with well-established fibrocystic infections in the muscle fibers, associated with post mortem myoliquefaction.

T1-Weighted Dynamic Contrast-Enhanced MR Perfusion Imaging Characterizes Tumor Response to Radiation Therapy in Chordoma

BACKGROUND AND PURPOSE

Chordomas notoriously demonstrate a paucity of changes following radiation therapy on conventional MR imaging. We hypothesized that dynamic contrast-enhanced MR perfusion imaging parameters of chordomas would change significantly following radiation therapy.

MATERIALS AND METHODS

Eleven patients with pathology-proved chordoma who completed dynamic contrast-enhanced MR perfusion imaging pre- and postradiation therapy were enrolled. Quantitative tumor measurements were obtained by 2 attending neuroradiologists. ROIs were used to calculate vascular permeability and plasma volume and generate dynamic contrast-enhancement curves. Quantitative analysis was performed to determine mean and maximum plasma volume and vascular permeability values, while semiquantitative analysis on averaged concentration curves was used to determine the area under the curve. A Mann-Whitney U test at a significance level of P < .05 was used to assess differences of the above parameters between pre- and postradiation therapy.

RESULTS

Plasma volume mean (pretreatment mean = 0.82; posttreatment mean = 0.42), plasma volume maximum (pretreatment mean = 3.56; posttreatment mean = 2.27), and vascular permeability mean (pretreatment mean = 0.046; posttreatment mean = 0.028) in the ROIs significantly decreased after radiation therapy (P < .05); this change thereby demonstrated the potential for assessing tumor response. Area under the curve values also demonstrated significant differences (P < .05).

CONCLUSIONS

Plasma volume and vascular permeability decreased after radiation therapy, suggesting that these dynamic contrast-enhanced MR perfusion parameters may be useful for monitoring chordoma growth and response to radiation therapy. Additionally, the characteristic dynamic MR signal intensity-time curve of chordoma may provide a radiographic means of distinguishing chordoma from other spinal lesions.