Acoustic Window Research Articles

L’imagerie cardiovasculaire dans l’insuffisance cardiaque

Transthoracic echocardiography remains the first-line cardiac imaging for diagnosis, management and screening of heart failure, whatever its phenotype (heart failure with reduced, mid-range and preserved ejection fraction). It allows anatomic characterization, systolic and diastolic functions of left and right ventricles assessment, intracardiac hemodynamic evaluation and for the assessment of valve disease. Myocardial deformation imaging (strain) is indicated in patients with heart failure for the assessment of systolic ventricles function and the diagnosis of specific heart diseases. Strain is indicated for the screening of preclinical myocardial dysfunction in patients at risk or exposed to cardiotoxic treatment. Altered global longitudinal strain is associated with a poor prognosis in heart failure. Cardiac magnetic resonance is recommended for the assessment of myocardial structure and function in subjects with poor acoustic window and patients with complex congenital heart diseases, in order to distinguish between ischemic and non-ischemic myocardial damage in patients with dilated cardiopathy and to characterize myocardial tissue in case of suspected specific heart disease.

Portable gamma-camera for the diagnosis of brain death diagnosis

ObjectiveTo evaluate the feasibility of using the Sentinella® portable gamma-camera for the diagnosis of brain death (BD). DesignA prospective, observational feasibility study was carried out. SettingIntensive Care Unit of a third level hospital. PatientsConsecutive recording was made of the adults diagnosed with brain death based on clinical criteria following admission to the Intensive Care Unit in the period from January to December 2017. InterventionsThe procedure was performed at the patient bedside with the intravenous administration of technetium 99 metastable hexamethylpropylene amine oxime. The absence of perfusion in the cerebral hemispheres and brainstem was described as a pattern consistent with BD. The diagnosis was correlated to the transcranial Doppler and/or electroencephalographic findings. ResultsA total of 66.1% of the patients were men with an average age of 60 years [IQR: 51–72]. The most frequent causes resulting in BD were hemorrhagic stroke (48.2%, n=27), followed by traumatic brain injury (30.4%, n=17), ischemic stroke (10.7%, n=6) and post-cardiac arrest anoxic encephalopathy (7.1%, n=4). A clinical diagnosis of BD was made in all cases, and the portable gamma-camera confirmed the diagnosis in 100% of the patients with a pattern characterized by the absence of brain perfusion. In addition, the results were compared with the transcranial Doppler findings in 46 patients, confirming the presence of diastolic reverberation and/or systolic peaks. The electroencephalographic tracing was obtained in 10 cases, with the appearance of electrical silence, due to the absence of an acoustic window in the transcranial Doppler study. ConclusionsA portable gamma-camera could be a useful and feasible tool for the diagnosis of BD.

Mild hyperthermia by MR-guided focused ultrasound in an ex vivo model of osteolytic bone tumour: optimization of the spatio-temporal control of the delivered temperature

BackgroundMagnetic resonance guided focused ultrasound was suggested for the induction of deep localized hyperthermia adjuvant to radiation- or chemotherapy. In this study we are aiming to validate an experimental model for the induction of uniform temperature elevation in osteolytic bone tumours, using the natural acoustic window provided by the cortical breakthrough.Materials and methodsExperiments were conducted on ex vivo lamb shank by mimicking osteolytic bone tumours. The cortical breakthrough was exploited to induce hyperthermia inside the medullar cavity by delivering acoustic energy from a phased array HIFU transducer. MR thermometry data was acquired intra-operatory using the proton resonance frequency shift (PRFS) method. Active temperature control was achieved via a closed-loop predictive controller set at 6 °C above the baseline. Several beam geometries with respect to the cortical breakthrough were investigated. Numerical simulations were used to further explain the observed phenomena. Thermal safety of bone heating was assessed by cross-correlating MR thermometry data with the measurements from a fluoroptic temperature sensor inserted in the cortical bone.ResultsNumerical simulations and MR thermometry confirmed the feasibility of spatio-temporal uniform hyperthermia (± 0.5 °C) inside the medullar cavity using a fixed focal point sonication. This result was obtained by the combination of several factors: an optimal positioning of the focal spot in the plane of the cortical breakthrough, the direct absorption of the HIFU beam at the focal spot, the “acoustic oven effect” yielded by the beam interaction with the bone, and a predictive temperature controller. The fluoroptical sensor data revealed no heating risks for the bone and adjacent tissues and were in good agreement with the PRFS thermometry from measurable voxels adjacent to the periosteum.ConclusionTo our knowledge, this is the first study demonstrating the feasibility of MR-guided focused ultrasound hyperthermia inside the medullar cavity of bones affected by osteolytic tumours. Our results are considered a promising step for combining adjuvant mild hyperthermia to external beam radiation therapy for sustained pain relief in patients with symptomatic bone metastases.

Ventilated acoustic metamaterial window panels for simultaneous noise shielding and air circulation

The conflict between the acoustical performance and ventilation efficiency in conventional noise barriers limits their application potentials in several settings. To address this challenge, we design and experimentally demonstrate a ventilated tunable acoustic metamaterial for noise mitigation at targeted frequencies. Through the structure, a peak normal incidence sound absorption coefficient of more than 0.96 at 1000 Hz and the peak normal incidence sound transmission loss of 18 dB is achieved while maintaining the air circulation with a 45% open area of ventilation. Such a high absorption near the resonant frequency under the ventilation condition originates from high impedance matching between the metastructure and air. Next, we present a proof-of-concept for the fabrication of acoustic metapanels for large scale applications. A simple jigsaw puzzle-like assembly technique is used to interconnect the multiple unit cells, leading to the production of integrated metapanels. The experimental findings validate the potential applications of the proposed metapanels for low-to-mid frequency noise control in a small ventilated spaces.

Superficial Endometriosis can be Seen on Ultrasound: A Pilot Application of Saline-Infusion Sonopodography

Study Objective Saline-infusion sonoPODography (SPG) is a novel ultrasound procedure that involves introducing fluid into the pouch of Douglas (POD) via the uterus and tubes to create an acoustic window and enhanced contrast between tissues in the posterior compartment. We aim to demonstrate that SPG has utility in diagnosing superficial endometriosis (SE) in a non-invasive fashion. Design Prospective diagnostic accuracy study. Setting Tertiary healthcare center in Sydney, Australia from September 2018-March 2019. Patients or Participants Patients with symptoms of endometriosis planned for laparoscopy were recruited. Interventions SPG was done intra-operatively. Measurements and Main Results Laparoscopy was initiated to ascertain a reference standard visual diagnosis of endometriosis and to suction free fluid from the pelvis. The single SPG operator was blinded to this part of surgery. If fluid collected in the POD, SE of the posterior compartment was evaluated and compared to laparoscopic findings. SE on TVS was defined relative to peritoneal surfaces: 1) superficial hypoechoic areas, 2) hyperechoic projections, 3) cystic areas, 4) pockets of fluid, 5) filmy, irregular adhesions. 15/19 patients underwent successful SPG. Prevalence of overall endometriosis was 15/19 (79%); deep endometriosis (DE) 5/19 (26%); ovarian endometriomas 3/19 (16%); POD obliteration 2/19 (11%); SE 14/19 (74%). SPG diagnostic accuracy results are depicted in Table 1. Conclusion SPG was successfully completed in the majority of patients. In those without advanced endometriosis (i.e. POD obliteration), SPG is even more achievable and provides a reasonable sensitivity for overall SE and very good sensitivity for POD SE, which is the second most common site of SE. At present, SPG needs to be further evaluated but offers hope for a novel non-invasive diagnostic tool for SE.

Thermally Assisted Acoustofluidic Separation Based on Membrane Protein Content.

The over- and under-expression of certain proteins in extracellular vesicles has been observed in many physiological and pathological conditions; however, a simple method to sort vesicles based on contrast in protein content is yet to be developed. We herein present a nonaffinity-based method for rapid and inexpensive isolation of lipid vesicles based on their membrane protein content. Based on a composition-specific thermophysical property change of vesicles at different protein contents, an acoustic property change that enabled an acoustophoretic separation was observed. This change was demonstrated in a thermally modulated acoustofluidic device in the form of a shift in vesicle migration from the nodal plane to antinodal plane at a specific temperature known as the acoustic contrast temperature (TΦ). Using phosphatidylcholine vesicles containing the membrane proteins gramicidin D, alamethicin, and melittin at molar contents ranging from 0.001% to 10%, we observed that increasing the membrane protein content brought about conformational changes in the membrane which afforded the vesicles distinctive acoustic properties. Then, by establishing an acoustic contrast temperature window, vesicles with the same protein but different molar content were successfully separated. The efficiency of the separation was studied for various vesicle mixtures and a separation efficiency as high as 97% was accomplished. In order to confirm the technique's applicability for biological samples, sheep red blood cells with various melittin peptide contents similarly demonstrated the depressing effects of melittin on membrane bending modulus and depressed the TΦ of the cells. This method holds promise for a myriad of applications in the biomedical field, especially in bioanalytical research.

Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) hyperthermia for primary rectal cancer: A virtual feasibility analysis.

77 Background: MR-HIFU Hyperthermia (HT) is a non-invasive treatment modality with real-time thermometry that ensures accurate and precise heating of a target with minimal effect on adjacent tissue. This energy deposition within a tumour can produce local bioeffects resulting in thermal chemo- and radiosensitization. MR-HIFU has been shown to be safe and feasible in a companion phase I study for recurrent rectal cancer. The purpose of this study is to determine the feasibility of MR-HIFU in treating primary rectal tumours. Methods: With ethics approval, the anatomic characteristics and surrounding structures of rectal tumours diagnosed at Sunnybrook from 2014-2019 were retrospectively analyzed. Three orthogonal views of MR images were used to determine the potential ultrasound (US) beam path and organs at risk (OAR). In part 2 of the study, the gross tumour volume was delineated for 30 rectal tumours (10 low, mid &high). Image datasets were imported into the Sonalleve MR-HIFU workstation for virtual treatment simulation and planning to determine tumour targetability, coverage, optimal patient set-up, and transducer positioning. Results: Of the 105 tumours analyzed, 36, 52, and 17 were low, mid, and high, respectively. The average width of the acoustic window (sciatic notch) for the US beam path was 5.8 ± 1.4cm, average tumour length was 5.24 ± 2.0cm, and average beam path (skin to tumour edge) was 7.3 ± 1.9cm. Eighty one percent of tumours were ≤ 0.3cm from an OAR. Of the 24 virtually simulated tumours to date, 6/8 lower, 6/8 mid, and 1/8 upper rectal tumours were targetable by MR-HIFU. Conclusions: This is the first virtual analysis to evaluate MR-HIFU HT targetability in primary rectal cancer. Results from this study will support MR-HIFU HT as an option to enhance the treatment of primary rectal cancer. Acknowledgments: This study has been funded by the Canadian Cancer Society. Patient & tumour characteristics. [Table: see text]

Comparisons of two diaphragm ultrasound-teaching programs: a multicenter randomized controlled educational study

BackgroundThis study aims to ascertain whether (1) an educational program is sufficient to achieve adequate Diaphragm Ultrasound (DUS) assessments on healthy volunteers and (2) combining a video tutorial with a practical session is more effective in making learners capable to obtain accurate DUS measurements, as opposed to sole video tutorial.ResultsWe enrolledstep 1: 172 volunteers naïve to ultrasound. After watching a video tutorial, a questionnaire was administered and considered to be passed when at least 70% of the questions were correctly answered. Course participants who passed the theoretical test were randomized to either intervention or control group. Learners randomized to the interventional group underwent to a practical training, tutored by an expert, before accessing DUS examination. Participants randomized to the control group directly accessed DUS examination, without any practical training. DUS measurements by learners and tutors were recorded and checked for accuracy, according to predefined criteria. Detection of both acoustic windows and accurate DUS assessment was achieved by 83.7% learners of the intervention group while 3.5% only among controls (p < 0.0001). The subcostal view of the diaphragm was correctly identified by 92% and 65% learners in the intervention and control groups, respectively (p < 0.0001) while the apposition zone by 86% and 71% learners, respectively (p = 0.026). An accurate diaphragm displacement (DD) measurement was obtained by 91% and 45% learners in the intervention and control groups, respectively (p < 0.0001) while an accurate thickening fraction (TF) measurement by 99% and 21%, respectively (p < 0.0001). DD measurements by both groups of learners were significantly correlated with those assessed by expert tutors; however, a significant improvement of measurement accuracy was found in learners randomized to receive also the practical training, compared to controls.ConclusionsA combined approach consisting of a theoretical module followed by a practical training is more effective in managing acoustic windows and performing accurate measurements when compared to an exclusively theoretical course.Trial registration prospectively registered on clinicaltrials.gov (Identifier: NCT03704129; release date 17th October 2018).

P2740Quantitative assessment of the entire right ventricle from one acoustic window: an attractive approach in patients with congenital heart disease

Abstract Background Right ventricular (RV) function is recognized as a prognostic factor in congenital heart disease (CHD). The accuracy of established parameters as tricuspid annular plane systolic excursion (TAPSE), right ventricular fractional area change (RVFAC) and tissue Doppler imaging (TDI S') are limited as the parameters reflect only a limited region of the RV. We previously introduced a novel four-view approach with different RV walls visualized in their long axis from one apical view using 2D-transthoracic echocardiographic (TTE) iRotate mode. Aims To extensive evaluate the entire RV function using iRotate echocardiography in a whole spectrum of CHD patients with abnormally loaded RV; both feasibility and RV echocardiographic parameters as comparison with healthy subjects is evaluated. Methods and results One hundred and forty-two CHD patients with abnormally loaded RV and 89 healthy subjects were included. All subjects underwent complete TTE with evaluation of TAPSE, TDI S' and peak systolic global longitudinal RV strain (RV-GLS) from the RV walls using the four-view iRotate model. The feasibility of TAPSE and RV S' ranged between 94% and 100%. The feasibility of RV-GLS in CHD was 98%, 69%, 87% and 72% respectively in the lateral, anterior, inferior and inferior coronal view walls. With the exception of RV S' in the inferior coronal view, all parameters were significantly lower in the CHD vs healthy subjects (p&lt;0.001) (Table). i-Rotate RV wall GLS (%) RV wall GLS (%) Measurement Feasibility Congenital (n=142) Controls (n=89) P-value Lateral 97.9 −17.6±5.0 −25.4±4.5 &lt;0.001 Anterior 69.0 −15.9±4.9* −24.2±4.5 &lt;0.001 Inferior 88.7 −17.2±4.7 −23.3±4.4 &lt;0.001 Inferior coronal view 72.5 −15.1±4.5* ** −20.8±5.2 &lt;0.001 Data expressed as mean ± SD or %. p&lt;0.05 for *Lateral vs Anterior and vs Inferior CV; **Inferior vs Inferior CV. Conclusion The feasibility of all RV parameters in the four-axis iRotate model is excellent in CHD and represents a reproducible, easily applicable and complete RV assessment in daily practice. RV function is significantly decreased in the CHD group using both load dependent and independent parameters. Complete RV strain analysis reveals regional differences in patients with CHD.

P4546Acute heart failure: speckle tracking echocardiography, a new ally in intensive care unit

Abstract Background Acute Heart Failure (AHF) is a life-threatening condition with high mortality rate. Purpose The aim of our study was to identify the best predictors of in-hospital mortality and stay, among laboratory blood tests, clinic and echocardiographic (standard and by Speckle Tracking Echocardiography, STE) parameters in patients admitted to our Intensive Care Unit (ICU) for AHF. Methods We enrolled 57 patients (age 70±13 y, 70% man) admitted to our ICU with de novo AHF or acute decompensation of Chronic Heart Failure (CHF). Exclusion criteria were: active malignancies, chronic liver disease, absent acoustic echocardiographic window and patient refusal. At ICU admission, all patients were assessed with vital signs (heart rate, HR; systolic blood pressure, SBP), blood laboratory tests, standard echo and STE of left ventricle (LV), right ventricle (RV) and left atrium (LA). These indexes were then related to the length of stay and mortality. Results The population was finally composed of 52 patients, due to 5 in-hospital deaths. 56% had an ischemic aetiology, 26% idiopathic dilated cardiomyopathy, 11% valvular diseases, 7% other causes of HF. At admission, average HR was 78±16 bpm, SBP 119±24 mmHg and EF 33±13%. Among all the parameters, the ones that showed significant statistical correlation with the length of hospitalization (15,34±7.03 days) were plasmatic creatinine, SBP, Systolic Pulmonary Artery Pressure, high LV filling pressure (E/E' &gt;12) and Peak Atrial Longitudinal Strain (PALS). The maximal dose of intravenous loop diuretics and inotropic drugs also showed a good correlation. Analysing the two sub-populations with mortality data, we observed that patients who died, had a significantly lower EF (19±9.62% vs 35±12.55%; p=0,01), but not a higher left atrial volume indexed (31.04±14.87 vs 26.36±12.03 ml/m2; p= ns) compared to the survivors; instead PALS was significant worse (10.08±4.62 vs 20.64±13,35%; p&lt;001). Free wall RV Longitudinal Strain (fw-RVLS) values for the patients who died (−9.41±4.66%) were significantly lower than in survivors (−13.67±6.02%; p&lt;0.01). LVGLS (Left Ventricular Global Longitudinal Strain) did not show statistical significant differences between the two populations. Based on the results of ROC analysis (Figure 1), we created a score to predict in-hospital mortality, composed of: EF, PALS and RVLS-free wall. The ideal cut point to predict mortality was &gt;1.5. Figure 1 Conclusions AHF represents one of the major challenges in ICU. The use of a combined echocardiographic score, assessed at admission, could help to better predict mortality risk, in addition to commonly used indexes.

P5874D Flow cardiac magnetic resonance quantification of mitral regurgitation, comparison with transthoracic echocardiography

Abstract Background Mitral valve regurgitation (MR) is currently primarily assessed by a multiparametric approach with transthoracic echocardiography (TTE) that can be further completed by 2D Cardiac Magnetic Resonance (2D CMR) in case of doubt or poor acoustic window. TTE and 2D CMR have nevertheless imperfect agreement in terms of MR quantification. Time-resolved phase-contrast cardiac magnetic resonance imaging with flow-encoding in three spatial directions (4D Flow CMR) could help in MR quantification. Purpose Compare 4D Flow CMR quantification of MR with TTE using a multiparametric approach. Methods We conducted a monocentric, prospective study at the Institut Mutualiste Montsouris in Paris between November 2016 and 2017 including patients with chronic primitive MR. MR was evaluated with a multiparametric approach by two cardiologists with TTE and quantitatively by two radiologists with 4D Flow CMR. MR was classified as mild, moderate or severe and evaluated blindly with consensus in case of disagreement. 4D Flow CMR measurements consisted in quantifying MR regurgitant volume (RV) and MR regurgitant fraction (RF). 4D anterograde mitral flow was compared to left ventricular stroke volume using 2D-cine CMR. Results 33 patients were included. Inter-observer agreement was good in TTE (kappa= 0.75 95% CI [0.57- 0.92]) and excellent in 4D Flow CMR (ICC= 0.94 95% CI [0.79–0.95]). Agreement with TTE was excellent using optimized thresholds (Mild: RV≤20mL RF≤20%, Moderate: RV=21–39mL RF=21–36%, Severe: RV≥40mL RF≥37%): kappa= 0.93 95% CI [0.8–1] for RV and kappa= 0.90 95% CI [0.7–0.9] for RF. A validation cohort confirmed that the 4D flow thresholds as determined were accurate for MR grading. Agreement between 4D anterograde mitral flow and 2D-cine CMR left ventricular stroke volume was also excellent (ICC= 0.92 95% CI [0.85–0.96]). Conclusion 4D Flow CMR is a reliable tool for MR quantification. It provides direct quantitative evaluation of MR with low inter-observer variability. It may therefore be used as a gatekeeper before therapeutic decisions such as surgery.

P5981Impact of radiotherapy on myocardial function and paravalvular leaks after transcatheter aortic valve implantation (TAVI)

Abstract Introduction Thanks to the anticancer therapies, the life expectancy of the oncologic patients has noticeably increased, but several cardiac diseases can be observed in these patients as the result of the cardiotoxic effects. Purpose To investigate the impact of radiotherapy on the clinical and echocardiographic outcomes, in patients with severe aortic stenosis (AS) and preserved left ventricle ejection fraction (LVEF) treated with transcatheter aortic valve implantation (TAVI). Methods We recruited patients with severe AS and left ventricular ejection fraction (LVEF) ≥50‰ treated with TAVI and who received prior radiotheraphy. Patients with LVEF &lt;50‰, treated with valve in valve, with inadequate acoustic windows or the absence of echocardiographic images pre-TAVI and after 3–6 months were excluded. Demographic, clinical and echocardiographic data were recorded. Results 102 patients were included in the present analysis. They were divided in two groups: 19 (18‰) with an oncologic history treated with previous left thoracic/mediastinal radiotherapy and 83 (82‰) patients without an oncologic history. The two groups were homogeneous in terms of demographic and clinical data, brain natriuretic peptide (BNP), echocardiographic data pre-TAVI. They only differed for a greater prevalence of mitral stenosis and calcifications in the oncologic patients versus the non-oncologics (respectively 36‰ vs. 12‰ p=0,016; 73‰ vs. 29‰ p=0,001). No differences in terms of in-hospital clinical outcomes were observed. The echocardiographic evaluation in both groups showed a significant decrease of the peak velocities and of the transprosthetic gradients. There was a higher incidence of at least moderate degree paraprosthetic leaks in the oncologic group vs. the non-oncologic one: 6 (31‰ total leaks, 37‰ leaks &gt;2+) vs. 7 (8‰ total leaks, 12‰ leaks &gt;2+); p=0.029. After 3–6 months, there was not a statistically significant improvement of ejection fraction (EF) in neither of the two groups but there was a statistically significant improvement of transmural, subepicardial and subendocardial longitudinal strain values in the non-oncologic group compared to pre-TAVI values, respectively −19±4 vs. −17±4 (p&lt;0.001); −17±3 vs. −15±3 (p&lt;0.001); −22±4 vs. −19.8±4 (p&lt;0.001). Any statistically significant improvement was detected in the group with history of anticancer treatments between the longitudinal strain values post and pre-TAVI (−18±3‰ vs. −16±3‰; −14±3‰ vs. −20±5‰; −20 ±± 5‰ vs. −19±4‰). Conclusions Patients affected by severe AS treated with TAVI and who received received prior radiotheraphy, showed the absence of statistically significant improvement of multilayer strain values, at 3–6 months after TAVI. Oncologic patients also had a higher incidence of haemodynamically relevant paravalvular leaks after the intervention, compared to the non-oncologic patients.

P1502Age- and gender-specific prognostic cutoff values of coronary flow velocity reserve in vasodilator stress echocardiography

Abstract Background Coronary flow velocity reserve (CFVR) of left anterior descending artery is useful for risk stratification during stress echocardiography (SE) as an add-on to regional wall motion abnormalities (RWMA), but the age-and sex-dependence of prognostic cutoff values remains unclear. Purpose To provide sex and age-specific prognostic cut-off values which may be needed to account for the physiologic decline of CFVR with age, and sex-related differences in resting flow. Methods In an observational, prospective, multicenter, registry study design, we enrolled from August 2003 to August 2017 in 4 Italian cardiology referral centers with accredited, quality-controlled stress echo laboratory a consecutive sample of 5,577 patients (of them, 2,284 women and 110 aged ≥85 years) referred to the SE lab for known or suspected coronary artery disease, after exclusion of patients with inadequate acoustic window (n=295), premature test interruption (n=105), and lost to follow-up (n=173).All underwent dual imaging (RWMA and CFVR) dipyridamole SE (0.84 mg/kg over 6') and were followed-up. All-cause death and non-fatal myocardial infarction were the main outcome measures. Median follow-up of 20 months (1st quartile 8, 3rd quartile 43 months), Results There were 649 hard events (236 deaths and 413 non-fatal myocardial infarctions), 288 of which occurred in women and 38 in patients ≥85 years. With a ROC analysis, the best prognostic cut-off value for CFVR was almost the same for men (2.03) and women (2.02) and consistent across all age strata (&lt;45 years: 2.03; 45–54 years: 2.04; 45–64 years: 2.03; 65–74 and 75–84 years: 2.0) except for the very elderly (&gt;85 years) who showed an optimal value of 1.90. Independent prognostic indicators were RWMA (HR=5.42, 95% CI=2.42–12.15; p&lt;0.0001) and reduced CFVR (HR=3.26, 95% CI 2.27–3.90; p&lt;0.0001) in patients aged &lt;85 years, and RWMA (HR=5.42, 95% CI=2.42–12.15; p&lt;0.0001) in patients aged &gt;85 years. Best prognostic cut-off value of CFVR Conclusion A sex-independent cut-off value of CFVR ≤2.0 provides the optimal risk stratification across all age groups, except those &gt;85 years in whom a lower cut-off &lt;1.90 is needed. Risk stratification is more effective for all age groups when CFVR is combined with RWMA.

P608Exercise testing and multi-parametric CMR assessment in patients with Ebstein anomaly

Abstract Background Ebstein anomaly (EA) is a rare congenital heart disease characterized by an apically displaced tricuspid valve. It is associated with tricuspid valve regurgitation and right heart dilatation leading to significant morbidity. While echocardiography remains the mainstay of routine outpatient cardiac imaging, assessment of right ventricular (RV) anatomy and function is still challenging. Cardiovascular magnetic resonance imaging (CMR) has been shown to be of advantage in these patients being free from acoustic window limitations and offering superior volume quantification. In the present study, parameters obtained from cardiopulmonary exercise testing (CPET) were compared to conventional and novel CMR parameters in patients with EA. Methods In this prospective single centre study, N=17 patients with EA (mean age = 33.8±12.7yrs; N=10 females) underwent clinical assessment, CPET and multi-parametric CMR. Maximal work load (maxWL) and peak oxygen uptake (maxO2) were derived from CPET. CMR studies were performed on a 1.5-T Philips scanner and respective CMR parameters comprised a) anatomical, b) functional and c) myocardial deformation values of both ventricles. Results The majority of patients presented in NYHA class I or II (mean NYHA = 1.6±0.7) and with normal or mildly elevated NT-proBNP values (mean NT-proBNP = 189±158pg/ml). CPET-based maxWL was 147.14±55 watts and maxO2 19.32±5 ml/kg/min. CMR-based mean LVEF was 57.1±6.4% and RVEF was 46.5±11.1%, respectively. Deformation imaging revealed (amongst others) a LV global longitudinal strain (LV-gLS) of −13.7±3.0 and a RV global longitudinal strain (RV-gLS) of −14.7±5.0. Non-ischemic presence of late-gadolinium-enhancement was documented in 36% of our patients. Comprehensive correlation analysis revealed a substantial correlation a) between LV-gLS and NYHA class (r=0.64, p=0.01), but not between RV-gLS and NYHA class (r=0.19, p=0.46), b) between serum NT-proBNP levels and maxO2 (r=−0.53, p=0.03) as well as maxWL (r=−0.63, p=0.02), and c) between LV-EF and LV-gLS (r=−0.64, p=0.01). Conclusion Our preliminary data suggest that serum markers such as NT-proBNP and novel CMR parameters such as LV-gLS – but not RV-gLS - correlate with CPET-derived exercise parameters in patients with EA. The predictive value of these parameters regarding cardiac disease progression in EA has to be evaluated in future follow-up studies.

P6488Prognostic value of right ventricular systolic function by speckle tracking echocardiography beyond conventional echocardiography in significant tricuspid regurgitation

Abstract Background Right ventricular (RV) systolic function is determinant in the evaluation of patients with significant tricuspid regurgitation (TR). Timely detection of RV dysfunction with conventional 2D echocardiography is limited by the geometry of the RV. RV strain has emerged as an accurate and sensitive tool for evaluation of RV function that can allow detection of subclinical RV dysfunction Purpose This study was aimed to evaluate the prognostic value of RV strain in stable patients with significant TR, in comparison with conventional parameters of RV systolic function. Methods Consecutive patients in stable clinical status with significant TR evaluated in the Heart Valve Clinic between 2015–2018 were included. RV systolic function was measured with conventional echocardiographic parameters (RV fractional area change [FAC], tricuspid annular plane systolic excursion [TAPSE]), DTI S wave (`S) and with STE derived peak global and free wall longitudinal strain (GLS, FW-LS respectively) using the EPIQ system. End-point included cardiovascular mortality, tricuspid valve surgery or heart failure Results A total of 70 patients were included (mean age was 74±8 years, 71% females). 5 patients were excluded due to poor acoustic window. According to ethyology, 94% were functional TR (60% due to left valve disease, 27% due to tricuspid annulus dilatation, 13% others). Mean values of RV function parameters are shown in the table. During a median follow up of 18 months [IQR: 4–28], 37% of the patients reached the combined end point (n=15 developed right heart failure, n=17 underwent tricuspid valve surgery, and n=3 died). Patients with events showed impaired RV-GLS and FW-LS. Both parameters were predictive of the combined endpoint (table 1). Conventional parameters of RV systolic function were not associated with outcomes. Mean ± SD Mean ± SD Mean ± SD HR (95% confidence interval) P value in Cox regression analysis in all patients in patients with events in patients without events TAPSE 20±5 20±7 21±5 0.97 (0.9–1.06) 0.56 DTI S wave 10.5±2 11±3 10±2 1.08 (0.87–1.35) 0.49 FAC 44±7 43±6 45±8 1.04 (0.97–1.1) 0.22 FW longitudinal strain (FW-LS) 18±5 −16±5* −20±5 0.91 (0.84–0.98) 0.02 Global longitudinal strain (GLS) 19±4 −16±4* −21±4 0.87 (0.81–0.95) 0.001 Conclusion In patients with asymptomatic TR, RV strain values are superior to conventional parameters to detect RV dysfunction. Among different measurements of RV function, RV GLS and FW-LS were the only predictors of poor prognosis. These parameters may be included in the serial evaluation of these patients.

Implications for maxillary and middle meningeal artery insonation

Ultrasonographic visualization of the maxillary artery and it’s branch middle meningeal artery in infratemporal fossa may allow for ultrasonographic assessment in headache and migraine, intracranial hematomas, and extracranial-intracranial by-pass surgery. This study included 50 healthy volunteers, 32 females and 18 males with a median age of 41 years. Infrazygomatic accoustic window, enlarged by patients medium opened mouth was used. This study confirms the possibility of insonatingboth maxillary and middle meningeal arteries in infratemporal fossa (maxillary in 85,71%, and middle meningeal arteries in 74.28% of cases, at a depth of 2.40 and 2.50 cm, respectively)throughthe easily accessible acoustic window below the zygomatic arch. Blood flow was directed anteriorly and away from the probe when both arteries were insonated. While all the measured hemodynamic characteristics differed significantly between the maxillary and the middle meningeal artery (p < 0.001), no significant variations were noted between the males and females, nor the left or right side (p > 0.05). The possibility of evaluating the blood flow in MXA has numerous implications in neurology as it is one of the main arteries branching of the external carotid artery, and a crucial artery in the extracranial-intracranial by-pass surgery. MMA has been in the center of interestof many studies regarding cephalalgia and migraine, as a method to treat acute bleeding and a posttraumatic aneurysm, also, as a treatment option for chronic subdural hematoma.

P3370Prevalence of right ventricular dysfunction according to different parameters: basal and one year after transcatheter aortic valve implantation

Abstract Background Right ventricle (RV) is not often specifically studied in patients with severe aortic stenosis (AS). It's difficult to find the correct tool to assess RV function with echocardiographic parameters, and the percentage of patients with dysfunction may vary depending on the parameter that we use. The aim of the study was to evaluate the prevalence of RV dysfunction basal and one year after transcatheter aortic valve implantation (TAVI), according to different parameters. Methods Consecutive patients with severe AS undergoing TAVI from January 2016 to July 2017 were included. RV anatomical and functional parameters were analyzed according to ESC and ASE guidelines. RV dysfunction was assessed using tricuspid annular plane systolic excursion (TAPSE) &lt;17 mm, fractional area change &lt;35%, systolic movement of the RV lateral wall by tissue Doppler imaging (RV-S'TDI) &lt;9.5 cm/s, global longitudinal (RV-GLS) and free wall strain (RV-FWS) using as cutting point [20]. Pre procedure echo, immediate post procedure and 1 year echo were analyzed. Statistical analysis was performed using SSPS version 22. Results The final study population consisted of 78 patients (115 patients were included, 37 were excluded due to suboptimal acoustic window for RV anatomical and functional evaluation), mean age 83.73±6.31 year-old, 38.2% females. We analyzed the percentages of RV dysfunction according to the different parameters evaluated before and in the control one year after. They are shown in Figure 1. Prevalence of RV dysfunction Conclusions The presence of RV dysfunction in patients with severe AS is higher than expected Our data suggest that RV function improve one year after TAVI, in terms of a reduction in the number of patients with dysfunction. The assessment of RV function is difficult, and there is no agreement on what tools are more accurate and useful. RV strain seems to be the most sensible parameter to assess RV function in patients with AS undergoing TAVI. Impact of these measurements in patients management needs further evaluation.

P1503Decrement of vortex formation time during dobutamine stress echo

Abstract Background Vortex Formation Time (VFT) is a novel index of systolic and diastolic function which may be also affected by left ventricular geometry, but has never been evaluated during dobutamine stress echocardiography (DSE) protocols. We sought to investigate the changes in VFT during DSE protocol. Methods DSE was performed in 50 consecutive patients. Patients with poor acoustic window, atrial fibrillation, cardiac valve disease or pacemaker were excluded. Apical four and apical two chamber views were acquired and the following parameters were calculated off- line without knowledge of DSE result both at rest and at peak: left ventricular end-diastolic and end-systolic volume, stroke volume, ejection fraction, stroke work, e and a wave peak velocity and VTI, TDI-derived mitral annular early diastolic velocity at the lateral wall and mitral valve diameter. VFT calculated according to the following equation: VFT = [4 *(1 − β) * α3 * EF]/π, where α = (LVEDV/α3)(1/3) and is affected by ventricular geometry and β = VTIa-wave/(VTIe wave + VTIa-wave) reflecting the atrial filling fraction. Results Median age of the study population was 61 [53–72], 38 men (76%) and 13 (26%) had an old myocardial infarction. Fifteen patients (30%) were positive for myocardial ischemia during DSE. At rest, median LVEDV was 121.5ml (101.8–148.0), median EF (%): 59.9 [54.4–64.1], median atrial filling fraction: 0.43 [0.40–0.48], median mitral valve diameter (cm): 2.8 [2.6–3.0] and median VFT: 2.44 [1.74–3.10]. At peak, median LVEDV was 102.0ml [86.4–122.3] median EF (%) 65.7 [58.8–69.8], median atrial filling fraction: 0.67 [0.59–0.73], median mitral valve diameter (cm): 2.7 [2.5–2.9] and median VFT: 1.45 [1.05–1.88]. VFT decreased in the whole population (Wilcoxon rank test, p&lt;0.001) (figure 1A) and when patients were stratified according to test result. Median VFT decrease was significantly higher in patients with a positive DSE (50%) than in patients with negative DSE (39%) (Mann- Whitney U test, p=0.048) (figure 1B). Figure 1 Conclusion The VFT decreased significantly during DSE and most prominently in patients with ischemic response. This may indicate the deterioration of left ventricular diastolic or systolic function as well as change in left ventricular geometry during DSE protocol.

P3371Impact of severe aortic stenosis on layer-specific longitudinal strain and its prognostic value

Abstract Background Global longitudinal strain (GLS) was used to detect early myocardial dysfunction in patients with aortic stenosis (AS), however few data are currently available on the different susceptibility of specific myocardial layer to increased wall stress and its prognostic role. The present study sought to investigate the relationship between changes in LV multilayer strain and the clinical outcome of patients with severe AS and preserved left ventricle ejection fraction (LVEF). Methods We included in the analysis 211 patients (56% males, mean age 73±12 years old) with severe AS and LVEF≥50%, divided in symptomatic (n=114) and asymptomatic group (n=97), and 50 controls matched for age and sex. Patients with moderate-to-severe concomitant valvulopathy and inadequate acoustic windows for evaluation by speckle tracking analysis were excluded. Clinical, demographic and resting echocardiographic data were recorded, including quantification of 2D GLS, subendocardial LS and subepicardial LS. Results Symptomatic patients had increased LV wall thickness and LV mass index than asymptomatic ones (p&lt;0.001), higher transaortic mean pressure gradients (48±14 vs 44±13 mmHg, p=0.004), and lower aortic valve areas (0.42±0.09 vs 0.45±0.08 cm2/m2, p&lt;0.017). GLS was significantly lower in patients with AS compared to controls, especially in symptomatic group (17.9±3.4 vs 19.1±3.1 vs 20.7±2.1%, p&lt;0.001 in symptomatic, asymptomatic and control groups respectively) suggesting an early, subtle, myocardial dysfunction. In particular, the analysis of layer-specific myocardial deformation revealed a marked difference in both the subendocardial LS (20.1±4.9 vs 21.7±4.2 vs 23.4±2.5%, p&lt;0.001) and subepicardial LS (15.8±3.1 vs 16.8±2.8 vs 18.3±1.8%, p&lt;0.001). At multivariable logistic regression analysis, subendocardial LS was independently associated to symptoms (OR=1.148, p=0.014), together with indexed left atrial volume (OR=1.035, p=0.007) and LV concentric remodelling (OR=2.429, p=0.031). During a mean follow up of 38 months (IQ range 18–60 months), 12 patients with asymptomatic severe AS had a cardiovascular (CV) death. The presence of a subendocardial LS &lt;22% at baseline was associated with a higher rate of CV events at 3 and 5-year follow-up (19% vs 5% at 3-year follow-up, and 22% vs 8% at 5-year follow-up, respectively; log-rank p=0.044). Conclusion In patients with severe AS, LS impairment involves all myocardial layers and is more prominent in the advanced phases of the disease. In this setting, the subendocardial LS appears to be independently associated to symptoms than subepicardial LS. In asymptomatic patients, a reduced value of subendocardial LS is associated with higher CV mortality at 3- and 5-year follow-up.

The use of a probe stabilizer to reduce musculoskeletal overload of ultrasound operators in routine diagnostic echocardiographic imaging

Introduction: Echocardiography is essential in the evaluation of patients with cardiovascular disease. Repetitive movements, however, expose ultrasound operators to a high risk of musculoskeletal strain injuries. Aim: We investigated to what extent a probe stabilizer could reduce repetitive movements. Materials and methods: The study population consisted of 31 male patients referred for routine transthoracic echocardiography. A good apical acoustic window was prerequisite for inclusion. Standard apical views and measurements were first recorded without using the probe stabilizer. Afterwards, the same apical views and measurements were acquired with utilization of the probe stabilizer. During the entire procedure, shoulder abduction and muscle activity of right forearm flexor and extensor muscles were recorded. To this purpose, an EMG-sensor was attached to the right lower arm and a gyroscope to the right shoulder blade. Results: Extreme right arm abduction (>30˚) occurred in 58% of the time with use of the stabilizer and in 98% of the time without (p <0.01). Activity of right forearm extensor muscles was 42% with and 60% without stabilizer (p = 0.04). For the flexor muscles these percentages were 47% and 87%, respectively (p <0.01). Use of the stabilizer did not affect the time needed for image acquisition (308s versus 309s, respectively, p = 0.46). Conclusions: This study demonstrated that the use of a stabilizer during acquisition of apical views in routine transthoracic echocardiography reduces the total time of shoulder abduction and the use of the right forearm muscles, while acquisition time was not affected.