Outcome of paediatric portopulmonary hypertension in the modern management era: A case report of 6 patients.

Portopulmonary hypertension is a rare but serious complication of portal hypertension or portosystemic shunting. Portopulmonary hypertension is an indication for liver transplantation or shunt closure. However, liver transplantation is contraindicated in patients with severe pulmonary arterial hypertension. Reported mortality rates are high in children with portopulmonary hypertension and there are scarce recommendations on its management. Our aim was to report on our real-world experience of managing portopulmonary hypertension in a specialised centre. We describe a series of 6 children with portopulmonary hypertension. Their median age at diagnosis was 13 years (range 10-15). The underlying liver conditions were cirrhosis of unknown origin (1), congenital portocaval shunts (3), biliary atresia (1), and portal vein cavernoma with surgical mesenterico-caval shunt (1). Median mean pulmonary arterial pressure was 47 mmHg (range 32-70), and median pulmonary vascular resistance was 6.6 Wood units (range 4.3-15.4). All patients except one were treated with a combination of pulmonary arterial hypertension-specific therapy (phosphodiesterase type 5 inhibitors and/or endothelin receptor antagonists and/or prostacyclin analogues). Three patients then benefited from shunt closure and the others underwent liver transplantation. Five patients showed improvement or stabilisation of pulmonary arterial hypertension with no deaths after a mean follow-up of 39 months. Based on our limited experience, early and aggressive treatment with a combination of pulmonary arterial hypertension-specific therapy significantly improves patients' haemodynamic profile and enables the performance of liver transplantation and shunt closure with satisfactory outcomes.

Compressed sensing MRI of different organs: ready for clinical daily practice?

OBJECTIVES: The aim was to evaluate the image quality and sensitivity to artifacts of compressed sensing (CS) acceleration technique, applied to 3D or breath-hold sequences in different clinical applications from brain to knee. METHODS: CS with an acceleration from 30 to 60% and conventional MRI sequences were performed in 10 different applications in 107 patients, leading to 120 comparisons. Readers were blinded to the technique for quantitative (contrast-to-noise ratio or functional measurements for cardiac cine) and qualitative (image quality, artifacts, diagnostic findings, and preference) image analyses. RESULTS: No statistically significant difference in image quality or artifacts was found for each sequence except for the cardiac cine CS for one of both readers and for the wrist 3D proton density (PD)-weighted CS sequence which showed less motion artifacts due to the reduced acquisition time. The contrast-to-noise ratio was lower for the elbow CS sequence but not statistically different in all other applications. Diagnostic findings were similar between conventional and CS sequence for all the comparisons except for four cases where motion artifacts corrupted either the conventional or the CS sequence. CONCLUSIONS: The evaluated CS sequences are ready to be used in clinical daily practice except for the elbow application which requires a lower acceleration. The CS factor should be tuned for each organ and sequence to obtain good image quality. It leads to 30% to 60% acceleration in the applications evaluated in this study which has a significant impact on clinical workflow. KEY POINTS: • Clinical implementation of compressed sensing (CS) reduced scan times of at least 30% with only minor penalty in image quality and no change in diagnostic findings. • The CS acceleration factor has to be tuned separately for each organ and sequence to guarantee similar image quality than conventional acquisition. • At least 30% and up to 60% acceleration is feasible in specific sequences in clinical routine.

An unusual thrombus location in a Heartmate 3TM device with fatal outcome.

Even if the HeartMate 3TM left ventricular assist device is associated with excellent outcomes, complications, such as pump thrombosis continue to affect patients on hemodynamic support. We report the history of a 68-year-old man who underwent implantation of an HeartMate 3TM as a bridge to transplantation. Nineteen months later, he developed signs of heart failure leading to cardiogenic shock. Neither clinical examination nor parameters from the device allowed a clear-cut diagnosis. Only surgical exploration revealed the presence of clots between the polyethylene terephthalate (Dacron®) and polytetrafluoroethylene tubes. This constitutes a weakness of this device for which we propose to the manufacturer for minimal modifications to overcome the problem.

3D-printed heart model to guide LAA closure: useful in clinical practice?

OBJECTIVES: Correct device sizing for left atrial appendage (LAA) closure remains challenging due to complex LAA shapes. The aim of our study was to investigative the utility of personalized 3D-printed models (P3DPM) of the LAA to guide device size selection. METHODS: Fifteen patients (75.4 ±8.5years) scheduled for LAA closure using an Amulet device underwent cardiac computed tomography (CT). The LAA was segmented by semiautomatic algorithms using Vitrea® software. A 1.5-mm LAA thick shell was exported in stereolithography format and printed using TangoPlus flexible material. Different Amulet device sizes on the P3DPM were tested. New P3DPM-CT with the device was acquired in order to appreciate the proximal disc sealing the LAA ostium and the compression of the distal lobe within the LAA. We predicted the device size with P3DPM and compared this with the device sizes predicted by transesophageal echocardiography (TEE) and CT as well as the device size implanted in patients. RESULTS: The device size predicted by 3D-TEE and CT corresponded to the implanted device size in 8/15 (53%) and 10/15 (67%), respectively. The predicted device size from the P3DPM was accurate in all patients, obtaining perfect contact with the LAA wall, without device instability or excessive compression. P3DPM-CT with the deployed device showed device deformation and positioning of the disk in relation to the pulmonary veins, allowing us to determine the best device size in all 15 cases. CONCLUSION: P3DPM allowed us to simulate the LAA closure procedure and thus helped to identify the best Amulet size and position within the LAA. KEY POINTS: • A 3D-printed heart model allows to simulate the LAA closure procedure. • A 3D-printed heart model allowed to identify the optimal Amulet size and position. • 3D-printed heart models may contribute to reduce the Amulet implantation learning curve.

Impact of iterative reconstructions on objective and subjective emphysema assessment with computed tomography: a prospective study.

OBJECTIVES: To prospectively evaluate the impact of iterative reconstruction (IR) algorithms on pulmonary emphysema assessment as compared to filtered back projection (FBP). METHODS: One hundred ten unenhanced chest CT examinations were obtained on two different scanners. Image reconstructions from a single acquisition were done with different levels of IR and compared with FBP on the basis of the emphysema index (EI), lung volume and voxel densities. Objective emphysema assessment was performed with 3D software provided by each manufacturer. Subjective assessment of emphysema was performed as a blinded evaluation. Quantitative and subjective values were compared using repeated ANOVA analysis, Bland-Altman analysis and Kendall's coefficient of concordance (W). RESULTS: Lung volumes are stable on both units, throughout all IR levels (P ≥ 0.057). EI significantly decreases on both units with the use of any level of IR (P < 0.001). The highest levels of IR are responsible for a decrease of 33-36 % of EI. Significant differences in minimal lung density are found between the different algorithms (P < 0.003). Intra- and inter-reader concordance for emphysema characterisation is generally good (W ≥ 0.77 and W ≥ 0.86, respectively). CONCLUSIONS: Both commercially available IR algorithms used in this study significantly changed EI but did not alter visual assessment compared to standard FBP reconstruction at identical radiation exposure. KEY POINTS: • Objective quantification of pulmonary emphysema is sensitive to iterative reconstructions • Subjective evaluation of pulmonary emphysema is not influenced by iterative reconstructions • Consistency in reconstruction algorithms is of paramount importance for pulmonary emphysema monitoring.

Multimodality imaging evaluation of a mitro-aortic fibrosa pseudoaneurysm fistulizing into both atria.

To our knowledge, we describe the first case of a pseudoaneurysm of the mitro-aortic intervalvular fibrosa fistulizing into both atria, following an aortic bacterial endocarditis and valve replacement.

[The place of balloon pulmonary angioplasty in the management of chronic thromboembolic pulmonary hypertension]. / Place de l'angioplastie percutanée dans le traitement de l'hypertension pulmonaire postembolique.

Chronic thromboembolic pulmonary hypertension (CTEPH) is uncommon. Its diagnosis should not be delayed as its prognosis is poor if not treated. In most cases, an acute pulmonary embolism is found in the medical history of the patient. Once suspected, a specific work-up should be performed in a pulmonary hypertension (PH) center. The ventilation/perfusion scan has a central role in this workup but the emergence of non invasive imaging technologies provides morphological and functional information which take part in the therapeutic decision making, such as operability. Surgical endarterectomy remains the only curative treatment. In some specific patients, percutaneous transluminal pulmonary angioplasty (AAP) is performed. This developing technique is a safe and efficient treatment on a clinical and hemodynamic standpoint. The main complication after AAP is lung reperfusion edema.

L'hypertension pulmonaire postembolique (CTEPH) est une maladie rare. Son diagnostic ne doit pas être retardé, compte tenu de son mauvais pronostic en l'absence de prise en charge adaptée. Dans la plupart des cas, un épisode d'embolie pulmonaire est retrouvé dans l'histoire médicale du patient. Une fois suspectée, la CTEPH nécessite une approche multidisciplinaire tant pour la stratégie diagnostique que thérapeutique. Les nouvelles techniques d'imagerie permettent de définir précisément le traitement de choix, tenant compte des comorbidités et de la topographie des lésions. Le seul traitement curatif reste l'endartérectomie pulmonaire. L'angioplastie percutanée des artères pulmonaires, effectuée dans des centres experts, se profile comme une alternative en cours de validation et doit se discuter au cas par cas. Cette technique permet de traiter non seulement des patients jugés inopérables mais également les patients avec une hypertension pulmonaire résiduelle postendartérectomie. La complication la plus fréquente est l'œdème de reperfusion.

Pulmonary Perfusion Changes as Assessed by Contrast-Enhanced Dual-Energy Computed Tomography after Endoscopic Lung Volume Reduction by Coils.

BACKGROUND: Endoscopic lung volume reduction by coils (LVRC) is a recent treatment approach for severe emphysema. Furthermore, dual-energy computed tomography (DECT) now offers a combined assessment of lung morphology and pulmonary perfusion. OBJECTIVES: The aim of our study was to assess the impact of LVRC on pulmonary perfusion with DECT. METHODS: Seventeen patients (64.8 ± 6.7 years) underwent LVRC. DECT was performed prior to and after LVRC. For each patient, lung volumes and emphysema quantification were automatically calculated. Then, 6 regions of interest (ROIs) on the iodine perfusion map were drawn in the anterior, mid, and posterior right and left lungs at 4 defined levels. The ROI values were averaged to obtain lung perfusion as assessed by the lung's iodine concentration (CLung, µg·cm-3). The CLung values were normalized using the left atrial iodine concentration (CLA) to take into account differences between successive DECT scans. RESULTS: The 6-min walk distance (6MWD) improved significantly after the procedure (p = 0.0002). No lung volume changes were observed between successive DECT scans for any of the patients (p = 0.32), attesting the same suspended inspiration. After LVRC, the emphysema index was significantly reduced in the treated lung (p = 0.0014). Lung perfusion increased significantly adjacent to the treated areas (CLung/CLA from 3.4 ± 1.7 to 5.6 ± 2.2, p < 0.001) and in the ipsilateral untreated areas (from 4.1 ± 1.4 to 6.6 ± 1.7, p < 0.001), corresponding to a mean 65 and 61% increase in perfusion, respectively. No significant difference was observed in the contralateral upper and lower areas (from 4.4 ± 1.9 to 4.8 ± 2.1, p = 0.273, and from 4.9 ± 2.0 to 5.2 ± 1.7, p = 0.412, respectively). A significant correlation between increased 6MWD and increased perfusion was found (p = 0.0027, R2 = 0.3850). CONCLUSIONS: Quantitative analysis based on DECT acquisition revealed that LVRC results in a significant increase in perfusion in the coil-free areas adjacent to the treated ones, as well as in the ipsilateral untreated areas. This suggests a possible role for LVRC in the improvement of the ventilation/perfusion relationship.

[Hereditary haemorrhagic telangiectasia: importance of a multidisciplinary approach]. / Maladie de Rendu-Osler-Weber: importance d'une prise en charge multidisciplinaire.

The Rendu-Osler-Weber disease, also known as hereditary haemorrhagic telangiectasia, is an autosomal dominant inherited disease. Its main manifestations are nosebleeds and digestive tract bleeding due to angiodysplasia. The presence of arteriovenous malformations in organs such as lung, liver, brain, etc. can cause serious complications (haemorrhage, stroke, brain abscess, hypoxemia, increased cardiac output, pulmonary arterial hypertension). Diagnosis is based on clinical criteria and can be confirmed by genetic analysis. The prevalence of this rare disease is 1/5,000 to 1/10,000 and its expression varies widely, even in the same family. The management must be multidisciplinary and based on prevention and treatment of bleeding complications as well as screening and treatment of arteriovenous malformations.

Image quality of low mA CT pulmonary angiography reconstructed with model based iterative reconstruction versus standard CT pulmonary angiography reconstructed with filtered back projection: an equivalency trial.

OBJECTIVE: To determine whether CT pulmonary angiography (CTPA) using low mA setting reconstructed with model-based iterative reconstruction (MBIR) is equivalent to routine CTPA reconstructed with filtered back projection (FBP). METHODS: This prospective study was approved by the institutional review board and patients provided written informed consent. Eighty-two patients were examined with a low mA MBIR-CTPA (100 kV, 20 mA) and 82 patients with a standard FBP-CTPA (100 kV, 250 mA). Region of interests were drawn in nine pulmonary vessels; signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. A five-point scale was used to subjectively evaluate the image quality of FBP-CTPA and low mA MBIR-CTPA. RESULTS: Compared to routine FBP-CTPA, low mA MBIR-CTPA showed no differences in the attenuation measured in nine pulmonary vessels, higher SNR (56 ± 19 vs 43 ± 20, p < 0.0001) and higher CNR (50 ± 17 vs 38 ± 18, p < 0.0001) despite a dose reduction of 93 % (p < 0.0001). The subjective image quality of low mA MBIR-CTPA was quoted as diagnostic in 98 % of the cases for patient with body mass index less than 30 kg/m(2). CONCLUSION: Low mA MBIR-CTPA is equivalent to routine FBP-CTPA and allows a significant dose reduction while improving SNR and CNR in the pulmonary vessels, as compared with routine FBP-CTPA. KEY POINTS: • Low mA MBIR-CTPA is equivalent to routine FBP-CTPA. • MBIR-CTPA may be achieved with drastic (93 %) dose reduction. • Low mA MBIR-CTPA should be studied in the setting of suspected PE.

Dual-energy computed tomography to detect early pulmonary vascular changes in children with sickle cell disease: a pilot study.

Introduction: Pulmonary hypertension (PH) is a rare but fatal complication of sickle cell disease (SCD) that is possibly reversible if treated early. Dual-energy computed tomography (DECT) is a valuable tool for diagnosing PH. We attempted to determine if DECT can detect early signs of PH in children with SCD. Methods: This prospective observational pilot study was conducted at the Geneva University Hospitals and was approved by the local human ethics committee (CCER 2019-01975). A written informed consent was obtained from the patients and/or their legal guardian. Eight children (consisting of five girls and three boys) with homozygous SCD were included in the study. They underwent full cardiological workup using transthoracic echocardiography (TTE) and cardiopulmonary exercise test (CPET), as well as DECT. Results: The median age of the children was 11 years old (range 8-12). All patients exhibited a normal biventricular systo-diastolic function using the TTE. The median tricuspid regurgitant jet velocity value was 2.24 m/s (range 1.96-2.98). Four children were found to have signs of vasculopathy detected on DECT. Of them, two had abnormal screening test results. They both had an increased VE/VCO2 slope during CPET and an increased TVR of >2.5 m/s on TTE. Conclusion: DECT is capable of identifying early signs of pulmonary vascular disease in children with SCD. Further studies are needed to understand the correlation between DECT abnormalities and hemodynamic pulmonary circulation better.

Krypton ventilation imaging using dual-energy CT in chronic obstructive pulmonary disease patients: initial experience.

PURPOSE: To evaluate the tolerance and level of enhancement achievable after inhalation of stable krypton. MATERIALS AND METHODS: This study was approved by the institutional review board and the local ethics committee. Written informed consent was obtained from all subjects. The study was planned as a Fleming two-stage design, enabling one to assess the effectiveness of a newer treatment or technique on a small number of patients. At the end of each stage, the results are computed, and the trial can be stopped if the effectiveness is less than a minimum success rate or greater than an expected success rate. After informed consent was obtained, a total of 32 patients (ie, two successive series of 16 patients each) with severe emphysema underwent a dual-source, dual-energy chest computed tomographic (CT) examination after inhalation of a mixture of stable krypton (80%) and oxygen (20%), with reconstruction of diagnostic and ventilation images. For each patient, two regions of interest were selected on a diagnostic image, one in a region of severe emphysema (presumed to be poorly ventilated or not ventilated) and a second one in a region devoid of structural abnormalities (presumed to be normally ventilated), with measurements of attenuation values on the corresponding ventilation image. RESULTS: All examinations were successfully performed, without adverse effects. Differences in attenuation between normal lung and emphysematous areas were found in 28 patients (88%; 95% confidence interval: 71%, 96.5%). The maximal level of attenuation within normal lung was 18.5 HU. Krypton attenuation difference between normal and emphysematous lung was significant, with a median value of 51.8% (P < .001). CONCLUSION: The level of enhancement after inhalation of krypton and its excellent clinical tolerance makes this gas eligible for ventilation CT examinations.

Non-Invasive Cardiac Output Determination Using Magnetic Resonance Imaging and Thermodilution in Pulmonary Hypertension.

Magnetic resonance imaging (MRI) can be used to measure cardiac output (CO) non-invasively, which is a paramount parameter in pulmonary hypertension (PH) patients. We retrospectively compared stroke volume (SV) obtained with MRI (SVMRI) in six localisations against SV measured with thermodilution (TD) (SVTD) and against each other in 24 patients evaluated in our PH centre using Bland and Altman (BA) agreement analyses, linear correlation, and intraclass correlation (ICC). None of the six tested localisations for SVMRI reached the predetermined criteria for interchangeability with SVTD, with two standard deviations (2SD) of bias between 24.1 mL/beat and 31.1 mL/beat. The SVMRI methods yielded better agreement when compared against each other than the comparison between SVMRI and SVTD, with the best 2SD of bias being 13.8 mL/beat. The inter-observer and intra-observer ICCs for COMRI were excellent (inter-observer ICC between 0.889 and 0.983 and intra-observer ICC between 0.991 and 0.999). We could not confirm the interchangeability of SVMRI with SVTD based on the predetermined interchangeability criteria. The lack of agreement between MRI and TD might be explained because TD is less precise than previously thought. We evaluated a new method to estimate CO through the pulmonary circulation (COp) in PH patients that may be more precise than the previously tested methods.

Correlation between Pulmonary Artery Pressure and Vortex Duration Determined by 4D Flow MRI in Main Pulmonary Artery in Patients with Suspicion of Chronic Thromboembolic Pulmonary Hypertension (CTEPH).

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the causes of pulmonary hypertension (PH) and requires invasive measurement of the mean pulmonary artery pressure (mPAP) during right heart catheterisation (RHC) for the diagnosis. 4D flow MRI could provide non-invasive parameters to estimate the mPAP. Twenty-five patients with suspected CTEPH underwent cardiac MRI. Mean vortex duration (%), pulmonary distensibility, right ventricular volumes and function were measured using 4D flow MRI and cine sequences, and compared with the mPAP measured by RHC. The mPAP measured during RHC was 33 ± 16 mmHg (10−66 mmHg). PH (defined as mPAP > 20 mmHg) was present in 19 of 25 patients (76%). A vortical flow was observed in all but two patients (92%) on 4D flow images, and vortex duration showed good correlation with the mPAP (r = 0.805; p < 0.0001). Youden index analysis showed that a vortex duration of 8.6% of the cardiac cycle provided a 95% sensitivity and an 83% specificity to detect PH. Reliability for the measurement of vortex duration was excellent for both intra-observer ICC = 0.823 and inter-observer ICC = 0.788. Vortex duration could be a useful parameter to non-invasively estimate mPAP in patients with suspected CTEPH.

International registry of congenital porto-systemic shunts: a multi-centre, retrospective and prospective registry of neonates, children and adults with congenital porto-systemic shunts.

BACKGROUND: Congenital portosystemic shunts (CPSS) are rare vascular malformations associated with the risk of life-threatening systemic conditions, which remain underdiagnosed and often are identified after considerable diagnostic delay. CPSS are characterized by multiple signs and symptoms, often masquerading as other conditions, progressing over time if the shunt remains patent. Which patients will benefit from shunt closure remains to be clarified, as does the timing and method of closure. In addition, the etiology and pathophysiology of CPSS are both unknowns. This rare disorder needs the strength of numbers to answer these questions, which is the purpose of the international registry of CPSS (IRCPSS). METHOD: A retrospective and prospective registry was designed using secuTrial® by the ISO certified Clinical Research Unit. Given that a significant number of cases entered in the registry are retrospective, participants have the opportunity to use a semi-structured minimal or complete data set to facilitate data entry. In addition, the design allows subjects to be entered into the IRCPSS according to clinically relevant events. Emphasis is on longitudinal follow-up of signs and symptoms, which is paramount to garner clinically relevant information to eventually orient patient management. The IRCPSS includes also three specific forms to capture essential radiological, surgical, and cardiopulmonary data as many times as relevant, which are completed by the specialists themselves. Finally, connecting the clinical data registry with a safe image repository, using state-of-the-art pseudonymization software, was another major focus of development. Data quality and stewardship is ensured by a steering committee. All centers participating in the IRCPSS have signed a memorandum of understanding and obtained their own ethical approval. CONCLUSION: Through state-of-the-art management of data and imaging, we have developed a practical, user-friendly, international registry to study CPSS in neonates, children, and adults. Via this multicenter and international effort, we will be ready to answer meaningful and urgent questions regarding the management of patients with CPSS, a condition often ridden with significant diagnostic delay contributing to a severe clinical course.

Chest computed tomography using iterative reconstruction vs filtered back projection (Part 2): image quality of low-dose CT examinations in 80 patients.

PURPOSE: To evaluate the image quality of an iterative reconstruction algorithm (IRIS) in low-dose chest CT in comparison with standard-dose filtered back projection (FBP) CT. MATERIALS AND METHODS: Eighty consecutive patients referred for a follow-up chest CT examination of the chest, underwent a low-dose CT examination (Group 2) in similar technical conditions to those of the initial examination, (Group 1) except for the milliamperage selection and the replacement of regular FBP reconstruction by iterative reconstructions using three (Group 2a) and five iterations (Group 2b). RESULTS: Despite a mean decrease of 35.5% in the dose-length-product, there was no statistically significant difference between Group 2a and Group 1 in the objective noise, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios and distribution of the overall image quality scores. Compared to Group 1, objective image noise in Group 2b was significantly reduced with increased SNR and CNR and a trend towards improved image quality. CONCLUSION: Iterative reconstructions using three iterations provide similar image quality compared with the conventionally used FBP reconstruction at 35% less dose, thus enabling dose reduction without loss of diagnostic information. According to our preliminary results, even higher dose reductions than 35% may be feasible by using more than three iterations.