Elevated Baseline Neutrophil Count Correlates with Worse Outcomes in Patients with Muscle-Invasive Bladder Cancer Treated with Chemoradiation

BACKGROUND

The role of inflammation in the development and prognosis of bladder cancer (BC) is now established. We evaluated the significance of neutrophil-to-lymphocyte ratio (NLR) and neutrophil count (PNN) in patients with localized BC treated with chemoradiation.

METHODS

Clinical characteristics and baseline biological data were retrospectively collected. We tested the association between NLR, PNN, and overall survival (OS) and progression-free survival (PFS).

RESULTS

One hundred and ninety-four patients were included. Median PNN was 4000.0/mm³ [1500.0-16,858.0] and median NLR was 2.6 [0.6-19.2]. In patients with NLR > 2.6, median OS and PFS were lower (OS: 25.5 vs. 58.4 months, p = 0.02; PFS: 14.1 vs. 26.7 months, p = 0.07). Patients with PNN > 4000/mm³ had significantly lower OS (21.8 vs. 70.1 months, p < 0.001) and PFS (13.7 vs. 38.8 months, p < 0.001). Contrary to NLR, PNN > 4000/mm³ was associated with shorter OS and PFS in multivariate analysis.

CONCLUSIONS

Elevated PNN at baseline was associated with worse OS and PFS. NLR was not an independent prognostic factor.

Comparison of short course radiotherapy with chemoradiotherapy for locally advanced rectal cancers in the elderly: A multicentre, randomised, non-blinded, phase 3 trial

BACKGROUND

There is no specific guideline for the treatment of locally advanced rectal cancers in the elderly. Here we compared R0 resection rate and degradation of autonomy based on the instrumental activities of daily living score between neoadjuvant, short course radiotherapy and chemoradiotherapy in this specific population.

PATIENTS AND METHODS

Patients ≥75 years with resectable T3-T4 rectal adenocarcinoma within 12 cm of the anal verge or T2 of the very low rectum were randomised between short course radiotherapy (5 × 5 Gy in one week) and chemoradiotherapy (50 Gy, 2 Gy/f, 5 weeks with capecitabine: 800 mg/m² twice daily, 5 days per week), with delayed surgery 7 ± 1 weeks for the two arms.

RESULTS

One hundred and three eligible patients were enrolled between January 2016 and December 2019 when the trial was closed due to poor accrual. The R0 resection rate (first co-primary objective) was 84.3%; confidence interval 95% [73.26-94.18] in the short course group and 88%; confidence interval 95% [77.77-96.60] in the chemoradiotherapy group (non-inferiority p = 0.28). The deterioration of the instrumental activities of daily living score was not different during the pre-operative phase, it was significantly more deteriorated in the chemoradiotherapy group at 3 months post-operative (44.8% versus 14.8%; p = 0.032) but was not different at 12 months post-operative (second co-primary objective). During pre-operative phase, 9.8% of patients in short course group and 22% of patients in chemoradiotherapy group presented a serious adverse event, but we observed no difference during the post-operative phase between the two groups.

CONCLUSION

Although the main objectives of the study were not achieved, the short course radiotherapy followed by delayed surgery could represent a preferred treatment option in patients ≥75 years with locally advanced rectal cancer; a new study must be performed to confirm the improvement in overall and specific survival results.

Modified DCF (Docetaxel, Cisplatin and 5-fluorouracil) chemotherapy is effective for the treatment of advanced rectal squamous cell carcinoma

Background

Advanced rectal squamous cell carcinoma (rSCC) is a very rare and aggressive entity, and the best initial management is crucial for long survival as well as organ preservation and quality of life. Whereas local diseases are treated with chemo-radiotherapy and salvage surgery, data are scarce on how to treat more advanced diseases, and the role of induction chemotherapy is unknown.

Methods

We retrospectively analyzed all consecutive patients with advanced rSCC and treated with modified DCF (docetaxel, cisplatin, 5-fluorouracil; mDCF) regimen, from January 2014 and December 2021 in two French centers. Exploratory endpoints were efficacy (overall survival, recurrence-free survival, response rate, organ preservation rate) and safety.

Results

Nine patients with locally advanced or metastatic diseases received a mDCF regimen and were included for analysis. The median age was 62.0 years, 7 patients (77.8%) were women, and all eight available tumors were positive for HPV, mostly (85.7%) to genotype 16. With a median follow-up of 33.1 months, 77.8% of patients were still alive and disease-free, and the median overall survival was not reached at six years. The objective response rate was 87.5% after mDCF, and the complete response rate was 25.0% after mDCF and was increased to 75.0% after chemoradiotherapy. Only one patient underwent surgery on the primary tumor, with a complete pathological response. The median mDCF cycle was eight over eight scheduled, and all patients received the complete dose of radiotherapy without interruptions.

Conclusions

Induction mDCF chemotherapy followed by chemoradiotherapy is safe and highly effective in patients with advanced rSCC, and should be considered as an option in metastatic stage or locally advanced disease with an organ-preservation strategy.

Evaluation of Takayasu's arteritis activity by ultrasound localization microscopy

Objectives

Use of sulphur hexafluoride microbubbles (MB) with ultrasound can provide arterial wall enhancement. The use of ultrafast imaging with MB super-localization offers the possibility of ultrasound localization microscopy (ULM) and thus a visualization of in vivo carotid vasa vasorum. We aim to perform in vivo Vasa vasorum imaging in the carotid wall in Takayasu's arteritis and to provide a correlation with the disease's activity.

Methods

Patients with Takayasu arteritis were consecutively included in the national referral centre. Assessment of activity was performed by NIH activity index, with measurement of biological inflammation, morphological evaluation by computed tomography (CT) angiography, and 18-fluorodeoxyglucose CT scan. Ultrafast ultrasound imaging was performed with a 7 MHz central frequency linear probe. A dedicated contrast imaging sequence (plane waves with 8 angles, frame rate 500 Hz, voltage 8 V, duration of 8 s), coupled with the intravenous injection of sulphur hexafluoride MB allow us to store the raw radio frequency data of the MB passage. After a pre-processing step to accumulate frames properly including a frames selection and a movement correction, the MB were localized then tracked, allowing reconstruction of the vasa vasorum. The inflammation was quantified through MB tracked and normalized for inter acquisition comparison.

Results

16 patients were included. 5 patients (median age 35.8 [24.5–46.0] years, 3 women) had active disease and 11 patients (37.2 [31.7–47.3] years, 9 women) had quiescent disease. The passage of MB allowed the visualisation of microvessels within the arterial wall for active cases. The number of MB detected per second in the wall was 118 [80–169] for active cases vs. 13 [10–15] for quiescent cases (p=0.0005).

Conclusion

ULM allows visualization of microvessels within the carotid wall, with significantly greater MB passage in active Takayasu arteritis. ULM provides for the first time a precise visualization in vivo of the vasa vasorum and gives access to quantification of the vascularity of the arterial wall.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Société française de cardiologie

Long-Term Disease Control After locoregional Pelvic Chemoradiation in Patients with Advanced Anal Squamous Cell Carcinoma

Introduction

The incidence of metastatic squamous cell carcinoma of the anus (SCCA) is increasing. Even if systemic docetaxel, cisplatin, and 5-Fluorouracil (DCF) provide a high rate of long-term remission, the role of pelvic chemoradiation (CRT) is unknown in this setting. We reported the safety and efficacy of local CRT in patients with synchronous metastatic SCCA who achieved objective response after upfront DCF.

Methods

Patients included in Epitopes HPV01 or Epitopes HPV02 or SCARCE trials and treated with DCF followed by pelvic CRT were included. Concurrent chemotherapy was based on mitomycin (MMC) (10 mg/m² for two cycles) and fluoropyrimidine (capecitabine 825 mg/m² twice a day at each RT treatment day or two cycles of intra-venous 5FU 1000 mg/m² from day 1 to day 4). Primary endpoints were safety, local complete response rate, and local progression-free survival (PFS). Secondary endpoints were PFS, overall survival (OS), and metastasis-free survival (MFS).

Results

From 2013 to 2018, 16 patients received DCF followed by a complementary pelvic CRT for advanced SCCA. Median follow-up was 42 months [range, 11-71]. All patients received the complete radiation dose. Compliance to concurrent CT was poor. Overall, 13/15 of the patients (87%) had at least one grade 1-2 acute toxicity and 11/15 of the patients (73%) had at least one grade 3-4 toxicity. There was no treatment-related death. The most frequent grade 3-4 adverse effects were neutropenia (36%), dermatitis (40%), and anitis (47%). Eleven patients (73%) had at least one chronic grade 1 or 2 toxicity. One patient had a grade 4 chronic rectitis (7%). Complete local response rate was 81% at first evaluation and 62.5% at the end of the follow-up. Median local PFS was not reached and the 3-year local PFS was 77% (95%CI 76.8-77).

Conclusions

In patients with metastatic SCCA who had a significant objective response after upfront DCF, local CRT was feasible with high complete local response rate. The good local control rate, despite interruptions due to toxicities and low CT compliance, underline the role of pelvic RT. The high rate of toxicity prompts the need to adapt CRT regimen in the metastatic setting.

Carotid plaque vulnerability assessed by combined shear wave elastography and ultrafast doppler compared to histology: the UF-plaque study

Purpose

New biomarkers are needed to assess the vulnerability of carotid plaque to guide carotid surgery decision. Ultrafast Ultrasound Imaging (UUI) provides an estimation of plaque stiffness by Shear Wave Elastography (SWE) and the quantification of wall shear stress (WSS) by ultrafast Doppler. We aimed at evaluating the plaque stiffness and WSS applied on the plaque as potential biomarkers of plaque vulnerability.

Methods

Patients were referred for carotid endarterectomy because of symptomatic or asymptomatic carotid stenosis. Their plaques were evaluated by UUI within 48 hours before surgery. For each plaque, WSS and SWE were obtained on a longitudinal view at the stenosis. After endarterectomy, gross analysis and histology were performed on each removed plaque.

Results

46 plaques with SWE data and 29 with WSS data were analysed. Histological analysis revealed 29 vulnerable and 17 stable plaques. Analysis of the Gray Scale Median by B mode, mean and standard deviation of stiffness by SWE were not helpful in identifying vulnerable plaques. Figure 1 presents the SWE acquisition on one plaque (A) and the distribution of plaque's stiffness average over all plaques showing the 4 ranges of stiffness (B). SWE analysis revealed that the percentage of stiffness range of [3–5] m/s was significantly increased in vulnerable plaques (p=0.048) (Figure 2A). WSS alone showed no significant difference between stable and vulnerable plaques regardless of which segment of the plaque was analysed. A multiparametric score using maximal WSS at the peak of the plaque associated with SWE texture analysis parameters was created by a stepwise analysis, leading to a score with a sensitivity of 80% and a specificity of 78%. The ROC curve of this score found an AUC of 0.85 (Figure 2B).

Conclusions

Multiparameter scoring including plaque stiffness and flow analysis using ultrafast ultrasound imaging allows an effective identification of histologically vulnerable carotid plaques.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Fédération Française de cardiologieSociété Française de Cardiologie Figure 1Figure 2

Twelve-months safety of valvosoft non-invasive ultrasound therapy (NIUT) in patients with severe symptomatic aortic valve stenosis: a first-in-human study

Background

Despite overall favourable outcome of surgical and transcatheter aortic valve replacement (SAVR/TAVR) in patients with severe calcific aortic stenosis (CAS), not all patients are eligible for an invasive treatment1 because of too high predicted mortality and complications.

Cardiawave© has developed a novel non-invasive ultrasound therapy (NIUT) device called Valvosoft to treat calcific aortic stenosis (CAS). Based on preclinical results2,3, a prospective first-in-human study was conducted in two centres in 10 patients in 2019 and a second one in 4 patients in 2020. All patients had symptomatic severe CAS and were not eligible for aortic valve replacement according to local heart teams.

Methods

Fourteen patients with severe symptomatic CAS not eligible for valve replacement were enrolled. Transthoracic therapeutic ultrasound was delivered by the Valvosoft transducer coupled with an echocardiographic phased-array probe for real-time monitoring. Clinical and echocardiographic evaluation were performed at baseline, discharge, 1-, 3-, 6- and 12-months follow-up. Additionally, the 4 patients of the second study had a brain-MRI performed before and after treatment to rule out silent cerebrovascular events.

Results

Patients were advanced in age (82.4±5.3 years) with severe comorbidities (57% with heart failure and 50% with coronary heart disease) and severe CAS. No adverse events occurred during the procedure other than isolated ventricular extrasystoles. No device- or procedure-related SAEs were reported at 1-month follow-up as adjudicated by the Clinical Event Committee (CEC). No death, stroke or TIAs or deterioration of neurological status were observed at 1-month follow-up for all 14 patients.

During 12-months follow-up, 5 out of the 14 patients died (from 2 to 7 months after the procedure). All deaths were adjudicated as non-procedure related. The survival rate was higher (100%, 93%, 79%, 64% at 1-, 3-, 6- and 12-months) comparing to the natural evolution of the disease on an equivalent studied population4 (94%, 73%, 73%, 54% at 1, 3, 6 and 12-months). No abnormality was detected in any of the 4 patients who had a brain-MRI before and after treatment.

Conclusions

NIUT seemed feasible and safe and in a small first cohort of very frail patients with severe comorbidities suffering from severe symptomatic CAS. Brain-MRIs performed before and after treatment ruled out silent cerebrovascular events. The survival comparison of the studied population contrasted to the natural evolution of the disease suggests that NIUT is beneficial for these patients with no other medical option.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): This study has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement 829492 and is supported by the French Government, managed by the National Research Agency (ANR) under the program “Investissements d'avenir” with the reference ANR-16-RHUS-0003 and ANR VALVOSOFT-17-CE19-0019-02.

A 3D high resolution MRI method for the visualization of cardiac fibro-fatty infiltrations

Modifications of the myocardial architecture can cause abnormal electrical activity of the heart. Fibro-fatty infiltrations have been implicated in various cardiac pathologies associated with arrhythmias and sudden cardiac death, such as arrhythmogenic right ventricular cardiomyopathy (ARVC). Here, we report the development of an MRI protocol to observe these modifications at 9.4 T. Two fixed ex vivo human hearts, one healthy and one ARVC, were imaged with an Iterative decomposition with echo asymmetry and least-square estimations (IDEAL) and a magnetization transfer (MT) 3D sequences. The resulting fat fraction and MT ratio (MTR) were analyzed and compared to histological analysis of the three regions (“ARVC triangle”) primarily involved in ARVC structural remodeling. In the ARVC heart, high fat content was observed in the “ARVC triangle” and the superimposition of the MTR and fat fraction allowed the identification of fibrotic regions in areas without the presence of fat. The healthy heart exhibited twice less fat than the ARVC heart (31.9%, 28.7% and 1.3% of fat in the same regions, respectively). Localization of fat and fibrosis were confirmed by means of histology. This non-destructive approach allows the investigation of structural remodeling in human pathologies where fibrosis and/or fatty tissue infiltrations are expected to occur.

3D ultrasound coronarography: first proof of concept study on isolated beating rat hearts

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Bettencourt Foundation

Background/Introduction

We demonstrated recently that Ultrafast ultrasound Doppler imaging can image the intramyocardial coronary circulation in beating hearts of large animals and patients [1]. Yet, ultrasound spatial resolution remains limited by wave physics and coronaries smaller than ∼100 µm could not be imaged. Ultrasound Localization Microscopy (ULM) [2] was recently introduced to tackle this issue and exploit the micrometric localization of microbubble contrast agents at ultrafast frame rate in order to image blood flows in micrometer vessels.

Purpose

The objective of this work was to demonstrate that 3D ultrafast ultrasound with contrast agents can provide the full 3D mapping of the coronary microcirculation with quantitative flow velocity on a beating rat heart.

Methods

Acquisitions were performed on ex vivo rat hearts (n = 5) with retrograde perfusion (Langendorff

model). A flow of a Krebs–Henseleit solution mixed with a diluted microbubbles solution (0.22%) was perfused at controlled pressure into the coronary arteries (between 5 and 15 mL/min). We used a 32 × 32 elements, 8-MHz matrix-array ultrasound transducer connected to a 1024-channel programmable ultrasound scanner. An ultrafast Doppler imaging sequence consisting of 9 plane waves was transmitted at a PRF of 20 kHz during 270 ms and repeated 40 times. After beamforming and SVD clutter filtering, the microbubbles were localized and tracked in 3D. Flow velocity were mapped at baseline and after infusion of Adenosine (10e-5 µMol) at constant coronary perfusion pressure (120 mm Hg). Eventually, the hearts were fixed using formaldehyde perfusion and imaged by µCT after injection of radio opaque agent.

Results

We successfully imaged the coronary blood flows of entire rat hearts. It revealed the entire vasculature from large main coronaries arteries (cross section up to 1 mm) to small arterioles (smaller than 40 µm). Coronary flow velocities ranged from [1 – 50] cm/s depending on the arteries diameter. Velocity estimates were validated in vitro in tubes of Ø0.58mm and were in good agreement with theoretical values of a Poiseuille’s flow (relative ratio of 10% for maximum velocities). After Adenosine infusion, perfusion flow rates increased 102% ± 50% (p &lt; 0.05) on average. Eventually, anatomy revealed by 3D ultrasound coronarography was in accordance with the anatomy revealed by the µCT.

Conclusion(s)

We demonstrated the feasibility of 3D ultrasound coronarography on isolated beating rat hearts. This technique has the potential to become a novel imaging tool to investigate the coronary micro-circulation and quantify non-invasively the Coronary Flow Reserve (CFR).

Abstract Figure. Ultrasound coronarography

Smart ultrasound device for real-time myocardial stiffness quantification of the human heart

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ERC

Introduction

Myocardial stiffness (MS) is crucial to understand cardiac biomechanics and evaluate cardiac function. We recently demonstrated that shear wave imaging using acoustic radiation force can provide quantitative end-diastolic MS in human patients [1] . However, the dependence of shear wave velocity with myofiber orientation remained a limitation and required to perform Shear Wave Velocity (SWV) estimations from different probe orientations which is challenging in clinical practice. We propose a new approach to provide real-time quantitative assessment of MS without dependence of the probe orientation based on a dedicated smart ultrasound (US) device.

Methods

A new US probe was designed and manufactured to generate acoustic radiation force along the central axis and track the SWV simultaneously along three different orientations to obtain an elliptic profile of SWS. The probe was connected to dedicated electronics and software to provide real-time end-diastolic MS with ECG gating. Validation was performed on 4 in-vitro calibrated phantoms (0.92 – 1.49 – 2.58 – 3.49 m/s) and on ex vivo porcine hearts. MS along and across the fibers were compared to the values measured by conventional shear wave imaging with a linear probe mounted on a rotation motor (angular step of 10°) (Aixplorer, Supersonic imaging). Finally, the in vivo feasibility and reproducibility of measuring MS of the antero-septal wall and of the right ventricular (RV) wall was assessed transthoracically on four human volunteer .

Results

In vitro results on phantoms showed a good agreement with calibrated value (r2 = 0.98, std = 4.8%). Elliptic profiles on ex-vivo porcine heart showed good agreement with Aixplorer measurements acquired at different angles, with a relative difference along the long axis (LA) of: Δ=7.0%, Δ=7.1%, Δ=9% respectively for left ventricle (LV), right ventricle (RV) and septum. Finally, myocardial SWV assessment in human volunteers was obtained successfully on the RV and on the septum in late diastole. The mean MS was 1.79+/- 0.15 m/s along the fiber direction, the  fractional anisotropy (FA) was 0.25 +/- 0.06 on septal wall  in good agreement with previous results [1] and 1.06 +/- 0.11 m/s along fibers orientation and a FA of 0.27 +/- 0.08 on RV.  Finally the beat to beat reproducibility of MS measurement was estimated to be 8.22%.

Conclusion

The new smart US device allowed non-invasive quantification of anisotropic myocardial tissues in real time. Results showed the accuracy of the methods. This approach could offer a new clinical tool for the evaluation of the myocardium in cardiomyopathies and in heart failure patients.

Abstract Figure. SWV on myocardium human volonteer

NACRE: A randomized study comparing short course radiotherapy with radiochemotherapy for locally advanced rectal cancers in the elderly—Preliminary results

4

Background: Neoadjuvant therapy followed by total mesorectal surgery is the standard of care for locally advanced rectal carcinoma (RC). In the elderly, often underrepresented in clinical trials, but who represent a very large number of patients, therapeutic proposals are not based on high levels of evidence. The NACRE study investigated the role of short course radiotherapy with delayed surgery in this population. Methods: The PRODIGE 42-GERICO 12 NACRE is a multicenter randomized clinical trial aimed at comparing Arm A preop radiochemotherapy (RCT) (50 Gy, 2Gy/fraction [fr]; 25 fr + capecitabine) and delayed surgery and Arm B short course radiotherapy (25 gy, 5Gy/fr, 5fr) and delayed surgery. Eligible patients (pts) had cT3 or cT4 (or cT2 of the very low rectum), M0 rectal adenocarcinomas <12 cm from the anal verge, age ≥75years, and WHO PS ≤2. Randomization was stratified by center, T (T2/T3-T4) stage and Age (≤80 or >80 years). Two primary end-points will be analyzed according to the hierarchical sequential procedure: firstly R0 resection rate (non-inferiority test with a 8% non-inferiority margin), secondly preservation of autonomy using IADL score (superiority test with 15% absolute difference margin); secondary end-point will be survival and toxicity. We present here the results for R0 resection, survival and toxicities. Results: 29 sites randomized 101 patients from 01/2016 to 08/2019, 59 were males (58.4%), median age was 80 years (range 75-91). Pts characteristics were well balanced. 14% of pts in arm A did not receive all of the planned neoadjuvant treatment compared to 0% in arm B. The R0 resection rate in arm B (86.0% [IC95% 73-94%]) was not-inferior to the R0 resection rate in arm A (89.8% [ic95% 77-97%]), p=0.04 (non inferiority test). With a median follow-up of 15.8 months (CI95%: 14.8-26.0), the 6 months death rate was 10.0% (CI95%: 3.0-22.0) in arm A and 3.92% (CI95%: 0 -13.0) in arm B. There is a significant difference in overall survival between the two arm in favor of arm B (p=0.04, LogRank test), and there is a trend in favor of arm B for specific survival (p=0.06 LogRank test). Disease free survival is not statistically different (p=0.9). 13 serious adverse events were observed in arm A during preoperative phase, 7 in arm B, 16 and 10 respectively during the post-operative phase. Conclusions: These preliminary results show that short course radiotherapy with delayed surgery is associated with better compliance than radiochemotherapy in elderly patients and could give an advantage in overall survival. This regimen may be preferred in elderly patients. Clinical trial information: NCT02551237.

Safety, feasibility and performance of Valvosoft non-invasive ultrasound therapy in patients with severe symptomatic calcific aortic valve stenosis. First-in-Man

Objectives

We recently developed a unique transthoracic non-invasive ultrasound therapy device called Valvosoft to treat aortic stenosis. The therapy consists in delivering trans-thoracically precisely focused and controlled short ultrasound pulses (&lt;20μsec) at a high acoustic intensity to produce non-thermal mechanical tissue softening of the calcified aortic valve with the ultimate aim of improving the valve opening. Ultrasound imaging enables to follow valve movements in real-time and thus targets the ultrasound waves on the valve with great precision. After having validated this concept in pre-clinical studies, we aimed at applying this technique in human. The primary objectives were to assess the safety and feasibility of this novel technique along with its performance by evaluation of the valve leaflets mobility and valve opening area.

Methods

This is a multi-center, prospective, controlled first-in-man study. Ten patients with severe symptomatic calcific aortic stenosis and not eligible for SAVR/TAVR underwent a Valvosoft ultrasound therapy. The therapy consists of 6 sessions of ultrasound therapy. The Valvosoft transducer is applied on the patient's chest and coupled at its center with an echocardiography phased array probe to allow real-time control of the therapy (cavitation bubble detection). Preselection of the region of interest is performed by echo still frame before each session. Ultrasonic evaluation was performed by an independent core lab at baseline, discharge, 30-day and 3 month follow-up along with clinical follow up.

Results

Enrolled patients were advanced in age (84.1±6.5 yrs) with severe comorbidities (8 with heart failure, 5 with coronary heart disease and 5 with kidney failure). All had extensive aortic valve calcification (mean calcification volume of 687.28 mm3) with mean AVA of 0.61±0.17 cm2 and mean pressure gradient of 37.5±10.5 mmHg (6 patients had SV&lt;35ml/m2). No adverse events were recorded during the procedures other than some benign ventricular extrasystoles. The mean treatment time was 52 minutes. At 3 months follow-up, one patient had died due to end stage heart failure not linked to the procedure (9 weeks post procedure) and another got finally TAVI (45 days post procedure). Of the other 8 patients, 6 experienced an improvement of their NYHA status. No device or procedure related major adverse events nor deterioration of neurological status were observed at 3 months follow-up. Of the 7 patients that had echo follow-up at 3 months (one patient refused to get echo evaluation), 5 increased the AVA (between 14% and 46%) and 4 patients decreased the mean pressure gradient (from 6% to 44%). No AI or EF deterioration occurred during follow up.

Conclusion

Non-invasive ultrasound therapy is feasible and safe in patients with severe aortic valve stenosis and is able to improve AVA and pressure gradient in some patient. Larger studies with longer follow up will need to be conducted.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Cardiawave SA, Paris, France

Quantitative imaging of coronary flows using 3D ultrafast Doppler coronary angiography

Coronary flow rate remains complex to assess in clinical practice using non-invasive, non-ionizing imaging tools. In this study, we introduce 3D ultrafast Doppler coronary angiography (3D UDCA), an ultrasound-based method to assess coronary blood flows in three-dimensions at high volume-rate and in one single heartbeat. We demonstrate that 3D UDCA can visualize the coronary vasculature with high temporal and spatial resolution and quantify the absolute flow. The feasibility of the technique was demonstrated in an open-chest swine model. The flow rate of the left-anterior descending artery (LAD) assessed by 3D UDCA was reconstructed successfully at the early diastolic and late diastolic phases and was in good agreement with an invasive gold-standard flowmeter during baseline, reactive hyperemia and coronary stenosis (r² = 0.84). Finally, we demonstrate that a coronary stenosis on the LAD can be visualized as well as its associated flow acceleration.

419 Revisiting cardiac Doppler index with single heart beat 4D ultrafast echocardiography

Funding Acknowledgements

European Research Council under the European Union’s Seventh Framework Programme (FP/2007-2013) / ERC Grant Agreement n° 311025 and the ANR-10-IDEX-00

Background

4D echocardiography has the strong potential to improve cardiac index quantification by providing reproducible and user independent measurements. Quantification of left ventricle volume and ejection fraction, for instance, have been shown to be more reliable using 4D echocardiography. However, Doppler index evaluation has not yet benefited from it, due to limited volume rates and single location estimation when assessing spectral Doppler.

Purpose

In this study, we propose to demonstrate the feasibility of performing semi-automatic evaluation of cardiac Doppler indices within a single heartbeat on three human hearts by performing 4D ultrafast echocardiography, a new technique allowing a drastic volume rate increase.

Methods

A 4D ultrafast echocardiography scanner prototype connected to a matrix probe was developed to image the human heart. The probe was positioned on the apical 4-chamber view of N = 3 volunteers. High volume rate (5200 volume/s) acquisitions were performed three times by two different trained cardiologists. 4D color flow and tissue Doppler imaging were computed from the each single heartbeat acquisition. Spectral Doppler were derived at each voxel of the volumes. Region of interest such as LV outflow tract, mitral inflow or basal inferoseptal locations were automatically detected. Doppler index were derived from Doppler spectra and tissue velocity curves at these locations, and were compared against indices obtained using a clinical procedure based on 2D echocardiography.

Results

For each acquisition and the three volunteers, major Doppler indices: E, A, E/A, S, e’, a’, e’/a’, s’, E/e’, cardiac output were successfully assessed during a single heartbeat. A high degree of similarity between the indices assessed by 4D ultrafast echocardiography and clinical 2D measurements were found.(p &gt; 0.05 for each index).

Conclusions

4D ultrafast echocardiography can quantify the major cardiac Doppler indices in a single heart beat acquisition. It promises to improve patient care by accelerating examination time and to improve results reproducibility by removing most of the operator dependency. It also offers a unique feature by enabling E/e’ index assessment in the same heart beat which could be of a great interest for atrial fibrillation patients.

Abstract 419 Figure.

3041Wall shear stress measurement by ultrafast vector flow imaging for atherosclerotic carotid stenosis

Background

Carotid plaque vulnerability assessment is an important factor in guiding the decision to treat significant carotid stenosis. Ultrafast Ultrasound Imaging (UF) offers the possibility of evaluating local flow velocities over an entire 2D image, allowing access to velocity measurements in contact with the arterial wall and to measure the wall shear stress (WSS).

Purpose

To evaluate the feasibility of WSS measurement in a prospective series of patients with carotid stenosis.

Methods

A 7.5 MHz linear probe of an Aixplorer scanner was used. UF acquisitions had 3 tilted plane waves transmits (−10; 0; 10°) and an effective frame rate of 5000Hz. We evaluated the flow velocity in 5 areas of the carotid wall: common carotid artery (1), plaque ascent (2), plaque peak (3), plaque descent (4), internal carotid artery (5) (Figure). WSS was computed with the vector field speed using the following formula, WSS=μ·δn·v with v the blood velocity, n the normal vector to the vessel wall and μ, the blood viscosity, calculated from the hematocrit value for each patient. WSS measurement method was first validated using a laminar flow phantom and known viscosity. And then, 33 patients were then prospectively evaluated, with a median carotid stenosis degree of 80% [75–85].

Results

Significant correlation was found between in vitro measurement and the theoretical WSS values (R2=0.95; p<0.001).In patients,the maximum WSS value over the cardiac cycle follows the shape of the plaque with an increase during the ascend, reaching its maximum value of 3.57 Pa [2.47–4.45] at the peak of the plaque, and a fall after passing the peak (0.99 Pa [0.8–1.32]) lower than the WSS values in the non-stenotic areas (1.55 Pa [1.13–1.90] for the common carotid artery) (Table).

Table 1 Wall's area Wall shear stress (Pa) Min Max Delta 1. Common carotid artery 0.14 [0.05–0.27] 1.55 [1.13–1.90] 0.73 [0.55–0.96] 2. Plaque's ascent 0.39 [0.24–0.59] 2.63 [1.89–3.28] 1.20 [0.89–1.79] 3. Plaque's peak 0.60 [0.32–0.89] 3.57 [2.47–4.45] 1.78 [1.44–2.46] 4. Plaque's descent 0.16 [0.13–0.22] 0.99 [0.80–1.32] 0.52 [0.34–0.73] 5. Internal carotid artery 0.17 [0.13–0.35] 1.37 [1.04–1.75] 0.72 [0.50–0.87] Results are median [25th–75th percentile].

Figure 1

Conclusion

UF provide reliable WSS values. High WSS was present at the peak of the plaque, whereas lowest WSS values were found at the post-stenotic zone. WSS evaluation may help to better characterize the carotid plaque vulnerability.

P2765Efficacy of venous recanalization by noninvasive pulsed cavitational ultrasound therapy on swine model of acute deep venous thrombosis

Background

Post thrombotic syndrome is a frequent complication of deep venous thrombosis and is associated with high morbidity and hospitalization. Treatments currently available are invasive, involve use of endovenous procedures with stents and balloons, and frequently require general anesthesia. Pulsed cavitational ultrasound therapy (PCUT) emerged recently as a new technique to destroy remotely soft tissue. We recently demonstrated that PCUT was able to recanalize non-invasively in in vitro model of acute venous thrombosis (human blood clot).

Purpose

We aim to test the safety and efficacy of venous recanalization by noninvasive PCUT in vivo swine model of acute venous thrombosis.

Methods

All the experiments were performed on White large X Landrace swine. We induced an acute femoral deep venous thrombosis by using occlusive balloons introduced from jugular and popliteal vein combined with local injection of 50 IU of human thrombin. A 3 cm length occlusive thrombosis was obtained after 2 hours. Swines were divided in three groups: one with PCUT without follow-up (n=11), one with PCUT and follow-up at 14 days (n=8), and a control group also followed for 14 days (n=5). Acutely and during the follow up all swines received curative anticoagulation. To achieve PCUT, a 2.25 MHz transducer centered by a linear probe was used and cavitation was obtained in the center of the vein (Figure). After manual determination of thrombus location, a robotic arm was used to automatically move the transducer along the thrombus. Effectiveness of recanalization was evaluated by echo-Doppler and phlebography. Safety was assessed by Doppler ultrasound of the insonified area (artery, veins and surrounding tissue) and by histological analysis (local femoral vein and artery and lungs for pulmonary embolism).

Results

Among the 24 swines, we obtained 22 occlusive venous thromboses and 2 partial. The median length of the thrombus was 26±4.4 mm with vein diameter of 8.5±1.6 mm. Acutely, thrombosis recanalization was systematically obtained among the 19 swine with PCUT with median treatment duration of 33 minutes with residual diameter of 2.9±0.9 mm. No extravasation of contrast material or hematoma was observed after the therapy. After a 14-day follow-up, 75% of recanalisation remain permeable vs. 0% of vein permeable in the no therapy group (p=0.008). Residual diameter was 2.6±1.2 mm, which correspond to 50% of the venous diameter. No vein or artery damage and no embolism or pulmonary infarction was observed in all pigs.

Figure 1

Conclusion

We have demonstrated in vivo the safety and the efficacy of PCUT for non-invasive venous recanalization, persistent after 2 weeks.

Acknowledgement/Funding

French society of cardiology

P1823Aortic walls elastic properties assessment with ultrafast ultrasound imaging in case of bicuspid aortic valve

Background

Magnetic resonance imaging allows evaluation of aortic stiffness by the maximum rate of systolic distension (MRSD) a new prognosis factor of aortic dilatation in patients with bicuspid aortic valve (BAV). MRSD requires a continuous monitoring of the aortic diameter during the cardiac cycle, not accessible to conventional echocardiography contrary to ultrafast ultrasound imaging (UF).

Purpose

To develop specific aortic sequences in ultrafast ultrasound imaging (UF) to provide access to the aortic MRSD

Methods

Tissue Doppler allowed a precise estimation of the movement of each wall and the fine variation of the aortic diameter. To automatically track the anterior and posterior aortic walls during the cardiac cycle, we developed in the laboratory a specific interface (Figure). MRSD was the maximum of the derivative of the diameter chande over time. To assess this new technique, 24 patients (10 BAV patients and 14 controls, mean age 45.8 vs. 40.7 years, p=0.464, respectively) were consecutively included at a reference center for BAV. The ascending aorta was evaluated at the sinus of Valsalva, the tubular aorta and the aortic arch with a phased array probe (Supersonic Imagine) and dedicated sequences at 2000 frames/s.

Results

The lab-made interface allowed to track the aortic diameter and to calculate the MRSD from the UF acquisitions for each patient. We found lower MRSD at the sinus of Valsalva in case of BAV in accordance with previously demonstrated higher stiffness at this segment by our team (Table).

Table 1. UF Aortic parameters for BAV patients and controls BAV patients Controls p (Mann Whitney) Sinus of Valsalva Diameter (mm) 26.2 [22.4–32.5] 27.09 [23.5–29.5] 0.796 MRSD (s–1) 1.05 [0.73–1.19] 1.51 [1.28–1.99] 0.023 Tubular ascending aorta Diameter 31.4 [29.4–32.2] 28.9 [22.6–31.5] 0.328 MRSD 0.94 [0.59–1.27] 1.09 [0.87–1.41] 0.353 Aortic arch Diameter 24.2 [23.7–24.8] 24.2 [18.9–24.5] 0.673 MRSD 0.57 [0.35–1.07] 0.85 [0.76–1.02] 0.257 Results are median [25th–75th percentile].

Figure 1

Conclusion

UF allows evaluation of aortic stiffness by MRSD using dedicated sequence and interface. As echocardiography, UF is easily accessible and therefore deserves attention from cardiologists taking care of BAV patients to evaluate the segmental aortic remodeling associated with BAV.

P4490Safety and feasibility of non invasive transthoracic pulsed cavitational ultrasound therapy (PCUT) on a swine aortic valve model

Background

Aortic valve stenosis is associated with age and comorbidities, which require exploring less invasive therapeutic approach to improve patient outcome. We previously demonstrated in vitro and in vivo that pulsed cavitational ultrasound therapy (PCUT) can improve calcified bioprosthesis stenosis by softening leaflets remotely. To apply this technique noninvasively we aim to test PCUT transthoracicalyin a swine model targeting aortic valve. Because calcified aortic valve model doesn't exist, we tested this technique on a normal valve.

Objective

Primary objective was to estimate the feasibility and safety of PCUT. Secondary objectiveswere to evaluate occurrence, severity and evolution of cardiovascular side effects during therapy and within follow-up period (30±5 days) with and without double antithrombotic treatment.

Methods

All the experiments were performed on normal aortic valves (n=19) of swine. The system was composed of a high-power multi-element transducer with electronic steering and 2D echocardiographic probe embedded in the center. Swine were divided in three groups: one with PCUT and no anti thrombotic treatment (n=10), a second with PCUT and one-month treatment of aspirin and clopidogrel (n=5) and third group sham (n=4). All groups were followed up after 30 days.

Results

The primary feasibility endpoint was successful in 100% of tests performed (n=16). A maximal amplitude of 70 MPa and −19 MPa respectively for positive and negative peak pressure was found at the focus point. Survival at 30 days was 100% and no life-threatening arrhythmia was recorded and no sustained ventricular arrhythmia (SVT >30 s) was noticed. For the secondary safety objectives,we recorded acutely, at the time of procedure, NSVT in 7 pigs which corresponded to a cumulated duration of 2.1 out of the 485.3 min of the total US delivery (0.4% of time). Mean cycle of NSVT was slow 428.9 ms in average (139.6 bpm). The interruption or decrease of power of US delivery allowed immediate cessation of cardiac arrhythmia in all cases. There was no evidence of damage to the valve and no observation of impairment of valvular function by echocardiography. Only one animal showed side effects (RV dilatation) and the RV returned to normal after cessation of the therapy with no sequelae at follow up. At follow up no significant findings biology disturbance or valve thrombosis was observed (creatinine, CK MB, hemoglobin, hematocrit, haptoglobin or red blood cell numbers). Antithrombotic treatment didn't demonstrate any advantage at follow up.

Conclusion

We demonstrated in vivo feasibility and safety of transthoracic PCUT targeting aortic valve without any serious adverse event and no significant histopathology damage. We hope that this first-time transthoracic delivery of very focused ultrasound at high power will pave the way to new non invasive approach of valve softening in case of human aortic valve calcified stenosis.

4D simultaneous tissue and blood flow Doppler imaging: revisiting cardiac Doppler index with single heart beat 4D ultrafast echocardiography

The goal of this study was to demonstrate the feasibility of semi-automatic evaluation of cardiac Doppler indices in a single heartbeat in human hearts by performing 4D ultrafast echocardiography with a dedicated sequence of 4D simultaneous tissue and blood flow Doppler imaging. 4D echocardiography has the potential to improve the quantification of major cardiac indices by providing more reproducible and less user dependent measurements such as the quantification of left ventricle (LV) volume. The evaluation of Doppler indices, however, did not benefit yet from 4D echocardiography because of limited volume rates achieved in conventional volumetric color Doppler imaging but also because spectral Doppler estimation is still restricted to a single location. High volume rate (5200 volume s^-1) transthoracic simultaneous tissue and blood flow Doppler acquisitions of three human LV were performed using a 4D ultrafast echocardiography scanner prototype during a single heartbeat. 4D color flow, 4D tissue Doppler cineloops and spectral Doppler at each voxel were computed. LV outflow tract, mitral inflow and basal inferoseptal locations were automatically detected. Doppler indices were derived at these locations and were compared against clinical 2D echocardiography. Blood flow Doppler indices E (early filling), A (atrial filling), E/A ratio, S (systolic ejection) and cardiac output were assessed on the three volunteers. Simultaneous tissue Doppler indices e' (mitral annular velocity peak), a' (late velocity peak), e'/a' ratio, s' (systolic annular velocity peak), E/e' ratio were also estimated. Standard deviations on three independent acquisitions were averaged over the indices and was found to be inferior to 4% and 8.5% for Doppler flow and tissue Doppler indices, respectively. Comparison against clinical 2D echocardiography gave a p  value larger than 0.05 in average indicating no significant differences. 4D ultrafast echocardiography can quantify the major cardiac Doppler indices in a single heart beat acquisition.

Assistance ventriculaire gauche par Impella® : indications, gestion et complications

L’assistance monoventriculaire Impella® est une assistance microaxiale non pulsatile dépourvue de fonction d’oxygénation et/ou de décarboxylation. Sur le principe de la vis sans fin d’Archimède, elle aspire le sang dans le ventricule gauche pour le réinjecter dans la racine de l’aorte en regard des ostia coronaires. Selon le modèle utilisé, le débit d’assistance antérograde ainsi généré varie de 2,5 à 5 l/min. De par son mode de fonctionnement, l’assistance Impella® permet une décharge ventriculaire efficace. Ses indications sont l’angioplastie coronaire à haut risque et le choc cardiogénique réfractaire aux agents cardiovasoactifs. Chez le patient assisté par une extracorporeal life support (ECLS), la pompe Impella® permet de limiter le risque de surcharge ventriculaire. Chez le patient exclusivement assisté par Impella® soit d’emblée ou après une association avec l’ECLS, la voie d’abord axillaire permet sa réhabilitation active y compris la déambulation et l’activité physique. Elle se révèle alors une mise à l’épreuve cliniquement pertinente du ventricule droit en vue d’une assistance de longue durée de type left ventricular assist device.

Self-adaptive ultrasonic beam amplifiers: application to transcostal shock wave therapy

Ultrasound shock wave therapy is increasingly used for non-invasive surgery. It requires the focusing of very high pressure amplitude in precisely controlled focal spots. In transcostal therapy of the heart or the liver, the high impedance mismatch between the bones and surrounding tissues gives rise to strong aberrations and attenuation of the therapeutic wavefront, with potential risks of injury at the tissue-bone interface. An adaptive propagation of the ultrasonic beam through the intercostal spaces would be required. Several solutions have been developed so far, but they require a prior knowledge of the patient's anatomy or an invasive calibration process, not applicable in clinic. Here, we develop a non-invasive adaptive focusing method for ultrasound therapy through the ribcage using a time reversal cavity (TRC) acting as an ultrasonic beam amplifier. This method is based on ribcage imaging through the TRC and a projection orthogonally to the strongest identified reflectors. The focal pressure of our device was improved by up to 30% using such self-adaptive processing, without degrading the focal spots size and shape. This improvement allowed lesion formation in an Ultracal^® phantom through a ribcage without invasive calibration of the device. This adaptive method could be particularly interesting to improve the efficiency and the safety of pulsed cavitational therapy of the heart or the liver.

A semi-analytical model of a time reversal cavity for high-amplitude focused ultrasound applications

Time reversal cavities (TRC) have been proposed as an efficient approach for 3D ultrasound therapy. They allow the precise spatio-temporal focusing of high-power ultrasound pulses within a large region of interest with a low number of transducers. Leaky TRCs are usually built by placing a multiple scattering medium, such as a random rod forest, in a reverberating cavity, and the final peak pressure gain of the device only depends on the temporal length of its impulse response. Such multiple scattering in a reverberating cavity is a complex phenomenon, and optimisation of the device's gain is usually a cumbersome process, mostly empirical, and requiring numerical simulations with extremely long computation times. In this paper, we present a semi-analytical model for the fast optimisation of a TRC. This model decouples ultrasound propagation in an empty cavity and multiple scattering in a multiple scattering medium. It was validated numerically and experimentally using a 2D-TRC and numerically using a 3D-TRC. Finally, the model was used to determine rapidly the optimal parameters of the 3D-TRC which had been confirmed by numerical simulations.

4D in vivo ultrafast ultrasound imaging using a row-column addressed matrix and coherently-compounded orthogonal plane waves

4D ultrafast ultrasound imaging was recently shown using a 2D matrix (i.e. fully populated) connected to a 1024-channel ultrafast ultrasound scanner. In this study, we investigate the row-column addressing (RCA) matrix approach, which allows a reduction of independent channels from N  ×  N to N  +  N, with a dedicated beamforming strategy for ultrafast ultrasound imaging based on the coherent compounding of orthogonal plane wave (OPW). OPW is based on coherent compounding of plane wave transmissions in one direction with receive beamforming along the orthogonal direction and its orthogonal companion sequence. Such coherent recombination of complementary orthogonal sequences leads to the virtual transmit focusing in both directions which results into a final isotropic point spread function (PSF). In this study, a 32  ×  32 2D matrix array probe (1024 channels), centered at 5 MHz was considered. An RCA array, of same footprint with 32  +  32 elements (64 channels), was emulated by summing the elements either along a line or a column in software prior to beamforming. This approach allowed for the direct comparison of the 32  +  32 RCA scheme to the optimal fully sampled 32  ×  32 2D matrix configuration, which served as the gold standard. This approach was first studied through PSF simulations and then validated experimentally on a phantom consisting of anechoic cysts and echogenic wires. The contrast-to-noise ratio and the lateral resolution of the RCA approach were found to be approximately equal to half (in decibel) and twice the values, respectively, obtained when using the 2D matrix approach. Results in a Doppler phantom and the human humeral artery in vivo confirmed that ultrafast Doppler imaging can be achieved with reduced performances when compared against the equivalent 2D matrix. Volumetric anatomic Doppler rendering and voxel-based pulsed Doppler quantification are presented as well. OPW compound imaging using emulated RCA matrix can achieve a power Doppler with sufficient contrast to recover the vein shape and provides an accurate Doppler spectrum.

A 3D time reversal cavity for the focusing of high-intensity ultrasound pulses over a large volume

Shock wave ultrasound therapy techniques, increasingly used for non-invasive surgery, require extremely high pressure amplitudes in precise focal spots, and large high-power transducers arranged on a spherical shell are usually used to achieve that. This solution allows limited steering of the beam around the geometrical focus of the device at the cost of a large number of transducer elements, and the treatment of large and moving organs like the heart is challenging or impossible. This paper validates numerically and experimentally the possibility of using a time reversal cavity (TRC) for the same purpose. A 128-element, 1 MHz power transducer combined with different multiple scattering media in a TRC was used. We were able to focus high-power ultrasound pulses over a large volume in a controlled manner, with a limited number of transducer elements. We reached sufficiently high pressure amplitudes to erode an Ultracal^® target over a 10 cm² area.

Real time shear waves elastography monitoring of thermal ablation: in vivo evaluation in pig livers

BACKGROUND

Thermal ablation is a widely used minimally invasive treatment modality for different cancers. However, lack of a real-time imaging system for accurate evaluation of the procedure is one of the reasons of local recurrences. Shear waves elastography (SWE) is a new ultrasound (US) imaging modality to quantify tissue stiffness. The aim of the study was to assess the feasibility and accuracy of US elastography for quantitative monitoring of thermal ablation and to determine the elasticity threshold predictive of coagulation necrosis.

METHODS

A total of 29 in vivo thermal lesions were performed in pig livers with radiofrequency system. SWE and B-mode images were acquired simultaneously. Liver elasticity was quantified by using SWE data and expressed in kilopascal. After the procedure, pathologic analysis of treated tissues was compared with US images. The sensitivity and positive predictive value of the SWE maps of tissue elasticity were calculated and compared with the boundaries of the pale coagulation necrosis areas found at pathology.

RESULTS

The liver mean elasticity values before and after thermal therapy were 6.4 ± 0.3 and 38.1 ± 2.5 kPa, respectively (P < 0.0001). For a threshold of 20 kPa, sensitivity (i.e., the rate of pixels correctly detected as necrosed tissue) was 0.8, and the positive predictive value (i.e., the rate of pixels in the elastographic map >20 kPa that actually developed coagulation necrosis) was 0.83.

CONCLUSIONS

Tissue areas with coagulation necrosis are significantly stiffer than the surrounding tissue. SWE permits the real-time detection of coagulation necrosis produced by radiofrequency and could potentially be used to monitor US-guided thermal ablation.