Exercise ventilatory response after COVID-19: comparison between ambulatory and hospitalized patients.

Inefficient ventilatory response during cardiopulmonary exercise testing (CPET) has been suggested as a cause of post-COVID-19 dyspnea. It has been described in hospitalized patients (HOSP) with lung parenchymal sequelae but also after mild infection in ambulatory patients (AMBU). We hypothesize that AMBU and HOSP have different ventilatory responses to exercise, due to different etiologies. We analyzed CPET realized between July 2020 and May 2022 of patients with persisting respiratory symptoms 3 mo after COVID-19. Chest computed tomography (CT) scan, pulmonary function tests, quality of life, and respiratory questionnaires were collected. CPET data were specifically explored as a function of ventilation (V̇e) and time. Seventy-nine consecutive patients were included (42 AMBU and 37 HOSP, median: 54 [44-60] yr old, 57% female). Patients were hospitalized for a median of 20 [8-34] days, with pneumonia (41%) or acute respiratory distress syndrome (ARDS; 30%). Among HOSP, 12(32%) patients had abnormal values for spirometry and 18(51%) for carbon monoxide diffusing capacity (P < 0.001). CPET showed no differences between AMBU and HOSP in peak absolute O2 uptake (V̇o2) (1.59 [1.22-2.11] mL·min-1; P = 0.65). Tidal volume (VT) as a function of V̇e, was lower in AMBU than in HOSP (P < 0.01) toward the end of exercise. The slope of the V̇e-CO2 production was higher than normal in both groups (30.9 [26.1-34.3]; P = 0.96). In conclusion, the severity of COVID-19 did not influence the exercise capacity, but AMBU demonstrated a less efficient ventilatory response to exercise as compared with HOSP. CPET with exploration of data as a function of V̇e and throughout the exercise better unveil ventilatory inefficiency.NEW & NOTEWORTHY We evaluated the exercise ventilatory response in patients with persisting dyspnea after severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection. We found that despite similar peak power and peak absolute O2 uptake, tidal volume as a function of ventilation was lower in ambulatory than in hospitalized patients toward the end of exercise, reflecting ventilatory inefficiency. We call for evaluation of minute ventilation with the exploration of data throughout the exercise and not only peak data to better unveil ventilatory inefficiency.

Pulmonary Recovery 12 Months after Non-Severe and Severe COVID-19: The Prospective Swiss COVID-19 Lung Study.

BACKGROUND: Lung function impairment persists in some patients for months after acute coronavirus disease 2019 (COVID-19). Long-term lung function, radiological features, and their association remain to be clarified. OBJECTIVES: We aimed to prospectively investigate lung function and radiological abnormalities over 12 months after severe and non-severe COVID-19. METHODS: 584 patients were included in the Swiss COVID-19 lung study. We assessed lung function at 3, 6, and 12 months after acute COVID-19 and compared chest computed tomography (CT) imaging to lung functional abnormalities. RESULTS: At 12 months, diffusion capacity for carbon monoxide (DLCOcorr) was lower after severe COVID-19 compared to non-severe COVID-19 (74.9% vs. 85.2% predicted, p < 0.001). Similarly, minimal oxygen saturation on 6-min walk test and total lung capacity were lower after severe COVID-19 (89.6% vs. 92.2%, p = 0.004, respectively, 88.2% vs. 95.1% predicted, p = 0.011). The difference for forced vital capacity (91.6% vs. 96.3% predicted, p = 0.082) was not statistically significant. Between 3 and 12 months, lung function improved in both groups and differences in DLCO between non-severe and severe COVID-19 patients decreased. In patients with chest CT scans at 12 months, we observed a correlation between radiological abnormalities and reduced lung function. While the overall extent of radiological abnormalities diminished over time, the frequency of mosaic attenuation and curvilinear patterns increased. CONCLUSIONS: In this prospective cohort study, patients who had severe COVID-19 had diminished lung function over the first year compared to those after non-severe COVID-19, albeit with a greater extent of recovery in the severe disease group.

[Pulmonary hypertension: how to differentiate rare from frequent etiologies?] / Hypertension pulmonaire : comment différencier les causes fréquentes et rares?

Pulmonary hypertension (PH) is a frequent finding. PH secondary to left heart diseases is the most prevalent form of PH. PH caused by lung diseases and/or hypoxia is the second most frequent cause. The patient should be addressed to an expert center if the PH does not seem to be secondary to a left heart disease or a lung disease, if the PH seems too severe for the underlying cardiac or pulmonary diseases or in the presence of risk factors for PH caused by rare etiologies (group 1, 4 and 5).

L'hypertension pulmonaire (HTP) est une manifestation clinique fréquente. L'HTP secondaire aux cardiopathies gauches est la forme la plus prévalente. La deuxième forme la plus fréquente est l'HTP associée à une pneumopathie et/ou à une hypoxie chronique. Le patient devrait être adressé à un centre expert si l'HTP n'est pas facilement attribuable à une cardiopathie gauche ou à une pneumopathie, si l'HTP semble trop sévère pour la cardiopathie ou la pneumopathie sous-jacente ou en cas de présence de facteurs de risque pour une HTP causée par une étiologie rare (groupes 1, 4 et 5).

One-year persistent symptoms and functional impairment in SARS-CoV-2 positive and negative individuals.

BACKGROUND: Persistent symptoms of SARS-CoV-2 are prevalent weeks to months following the infection. To date, it is difficult to disentangle the direct from the indirect effects of SARS-CoV-2, including lockdown, social, and economic factors. OBJECTIVE: The study aims to characterize the prevalence of symptoms, functional capacity, and quality of life at 12 months in outpatient symptomatic individuals tested positive for SARS-CoV-2 compared to individuals tested negative. METHODS: From 23 April to 27 July 2021, outpatient symptomatic individuals tested for SARS-CoV-2 at the Geneva University Hospitals were followed up 12 months after their test date. RESULTS: At 12 months, out of the 1447 participants (mean age 45.2 years, 61.2% women), 33.4% reported residual mild to moderate symptoms following SARS-CoV-2 infection compared to 6.5% in the control group. Symptoms included fatigue (16% vs. 3.1%), dyspnea (8.9% vs. 1.1%), headache (9.8% vs. 1.7%), insomnia (8.9% vs. 2.7%), and difficulty concentrating (7.4% vs. 2.5%). When compared to the control group, 30.5% of SARS-CoV-2 positive individuals reported functional impairment at 12 months versus 6.6%. SARS-CoV-2 infection was associated with the persistence of symptoms (adjusted odds ratio [aOR] 4.1; 2.60-6.83) and functional impairment (aOR 3.54; 2.16-5.80) overall, and in subgroups of women, men, individuals younger than 40 years, those between 40-59 years, and in individuals with no past medical or psychiatric history. CONCLUSION: SARS-CoV-2 infection leads to persistent symptoms over several months, including in young healthy individuals, in addition to the pandemic effects, and potentially more than other common respiratory infections. Symptoms impact functional capacity up to 12 months post infection.

[Hypoxemia: from pathophysiology to diagnosis]. / Hypoxémie : de la physiopathologie au diagnostic.

Hypoxemia is defined as a decreased oxygen partial pressure in arterial blood. This frequent clinical phenomenon can lead to tissue hypoxia and requires a prompt diagnostic approach to guide its management. Five pathophysiological mechanisms should be assessed in the presence of hypoxemia: alveolar hypoventilation, ventilation/perfusion mismatches, diffusion disorders, true shunts and a decrease in the partial pressure of inspired oxygen. In this article, we synthesize the main etiologies of hypoxemia based on respiratory pathophysiology and suggest a diagnostic approach for its evaluation.

L'hypoxémie est définie comme la diminution de la pression partielle en oxygène dans le sang artériel. Ce phénomène fréquent en clinique peut amener à une hypoxie tissulaire et nécessite une approche diagnostique rapide afin d'orienter sa prise en charge. Cinq mécanismes physiopathologiques doivent être évoqués devant une hypoxémie : l'hypoventilation alvéolaire, les inégalités de ventilation/perfusion, les troubles de la diffusion, les shunts vrais et la diminution de la pression partielle d'oxygène inspiré. Dans cet article, nous résumons les étiologies principales d'hypoxémie en se basant sur la physiopathologie respiratoire et proposons une démarche diagnostique pour son évaluation.

[Pulmonology 2021: year in review]. / Pneumologie.

Among the new therapeutic developments in pulmonology during 2021, we have identified three topics of interest. A new biotherapy is now available for the management of severe uncontrolled non-Th2 asthma. In the field of pulmonary arterial hypertension, upfront triple therapy at the time of diagnosis is associated with a survival benefit in high-risk patients. Riociguat is a therapeutic option for patients that remain at intermediate risk despite treatment with iPDE5. Sotatercept, a promising new class of drug for treatment of group 1 PAH will soon be available. Finally, the use of transbronchial cryobiopsies as a valid alternative to surgical lung biopsy for the diagnosis of diffuse interstitial lung diseases will also be discussed in this review.

Parmi les nouveautés thérapeutiques en pneumologie au cours de l'année 2021, nous aborderons trois sujets. Une nouvelle biothérapie est désormais disponible pour la prise en charge de l'asthme sévère non contrôlé non T-Helper 2. Concernant l'hypertension artérielle pulmonaire (HTAP), une triple thérapie d'emblée au moment du diagnostic est associée à un bénéfice sur la survie chez les patients à haut risque. Le riociguat est une option thérapeutique lors d'HTAP restant à risque intermédiaire malgré un traitement par inhibiteur de la phosphodiestérase de type 5, et le sotatercept vise une nouvelle cible thérapeutique prometteuse pour l'HTAP du groupe 1. Enfin, la place des cryobiopsies transbronchiques comme alternative valable à la biopsie chirurgicale pour le diagnostic des pneumopathies interstitielles diffuses selon des recommandations récentes se précise.

[COPD: Guidelines for primary care physicians]. / BPCO: recommandations pour les médecins de premiers recours.

Chronic obstructive pulmonary disease (COPD) is common and should be suspected in any patient with chronic dyspnea, cough, or sputum with a history of exposure to tobacco or harmful particles. Spirometry is used for diagnosis. Full evaluation includes the severity of obstruction and clinical data, following the Global Initiative for Chronic Obstructive Lung Disease guidelines. Although the only treatments that have an impact on mortality are tobacco cessation, pulmonary rehabilitation and, for advanced disease, oxygen therapy, new symptomatic treatment have recently been made available. The duration of antibiotic and corticosteroid treatment for exacerbations has been shortened. The new diagnostic and management recommendations are summarized in this article.

La bronchopneumopathie chronique obstructive (BPCO) est fréquente et doit être suspectée chez tout patient présentant une dyspnée, une toux ou des expectorations chroniques avec une anamnèse d'exposition au tabac ou à des particules nuisibles. La spirométrie permet son diagnostic. Son évaluation se base sur la sévérité de l'obstruction et la clinique et tient compte des recommandations du guide de la Global Initiative for Chronic Obstructive Lung Disease. Bien que les seuls traitements impactant la survie soient l'arrêt du tabac, la réhabilitation respiratoire et tardivement l'oxygénothérapie, des nouveautés sont apparues dans l'arsenal thérapeutique symptomatique. La durée du traitement antibiotique et corticostéroïde des exacerbations est raccourcie. Les nouvelles recommandations diagnostiques et de prise en charge sont résumées dans cet article.

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.

Cardiac Output Determination in Precapillary Pulmonary Hypertension: A Systematic Review.

BACKGROUND: Cardiac output determination is essential in precapillary pulmonary hypertension. While direct Fick is the gold standard, thermodilution is commonly used as the reference method. Moving to noninvasive methods would be highly beneficial for patients, avoiding repetitive invasive assessments. This systematic review followed 3 objectives: (1) assessing the validity of indirect Fick and thermodilution in precapillary pulmonary hypertension, (2) assessing the interchangeability of noninvasive cardiac output measurement methods against reference methods in precapillary pulmonary hypertension, and (3) detecting methodological heterogeneity in the included studies. METHODS: We systematically reviewed the literature using medical databases and following PRISMA guidelines. We included articles comparing an invasive or noninvasive cardiac output measurement method with thermodilution or direct Fick in precapillary pulmonary hypertension patients. Cutoffs of limits of agreement and percentage error derived from the Bland and Altman graph were used to accept interchangeability. To study methodological heterogeneity, we extracted 9 quality criteria from all studies. RESULTS: Eleven studies were included. None reached the suggested interchangeability criteria. The median number of the 9 assessed quality criteria was 2 with interquartile range (0-4). CONCLUSIONS: Further studies evaluating the reliability of thermodilution and the consequences of its use in precapillary pulmonary hypertension patients are necessary. No evidence supports the use of indirect Fick in precapillary pulmonary hypertension. The studied noninvasive methods could not be considered interchangeable with invasive methods. A robust methodology should be used to draw sensible conclusions.

[Pulmonary telerehabilitation†: a new standard†?] / Télé-réhabilitation pulmonaire†: un nouveau standard†?

Pulmonary rehabilitation is effective to improve shortness of breath, health status and exercise capacity. Telerehabilitation uses information and communication technologies to deliver rehabilitation program from a distance. A Cochrane review published in 2021 shows its equivalence to conventional pulmonary rehabilitation. The confinement induced by the COVID-19 pandemic has made patients with respiratory failure even more fragile and vulnerable, promoting the development of telerehabilitation. This article describes its modalities, sets out the scientific evidence for its effectiveness and develops perspectives for its development.

La réhabilitation pulmonaire est efficace pour réduire les symptômes, améliorer l'état de santé et la capacité d'effort. La télé-réhabilitation utilise les technologies de l'information et de la communication pour dispenser des activités de réhabilitation à distance. Une revue Cochrane parue en 2021 montre son équivalence à la réhabilitation pulmonaire conventionnelle. Le confinement induit par la pandémie de Covid-19 a rendu les patients avec insuffisance respiratoire encore plus fragiles et vulnérables, favorisant le développement de la télé-réhabilitation. Cet article en décrit les modalités, énonce les preuves scientifiques de son efficacité et propose des perspectives quant à son développement.

Effect of Lower Body Negative Pressure on Phase I Cardiovascular Responses at Exercise Onset.

We hypothesised that vagal withdrawal and increased venous return interact in determining the rapid cardiac output (CO) response (phase I) at exercise onset. We used lower body negative pressure (LBNP) to increase blood distribution to the heart by muscle pump action and reduce resting vagal activity. We expected a larger increase in stroke volume (SV) and smaller for heart rate (HR) at progressively stronger LBNP levels, therefore CO response would remain unchanged. To this aim ten young, healthy males performed a 50 W exercise in supine position at 0 (Control), -15, -30 and -45 mmHg LBNP exposure. On single beat basis, we measured HR, SV, and CO. Oxygen uptake was measured breath-by-breath. Phase I response amplitudes were obtained applying an exponential model. LBNP increased SV response amplitude threefold from Control to -45 mmHg. HR response amplitude tended to decrease and prevented changes in CO response. The rapid response of CO explained that of oxygen uptake. The rapid SV kinetics at exercise onset is compatible with an increased venous return, whereas the vagal withdrawal conjecture cannot be dismissed for HR. The rapid CO response may indeed be the result of two independent yet parallel mechanisms, one acting on SV, the other on HR.

[Diagnostic approach to chronic dyspnea in adults]. / Approche diagnostique de la dyspnée chronique chez l'adulte.

Dyspnea is a symptom resulting from a complex interaction between multiple mechanisms that are not fully understood to this day. Chronic dyspnea is defined as dyspnea lasting more than one month and this symptom is commonly seen in primary care. Cardio-respiratory pathologies account for approximately 85 % of all cases of dyspnea. Dyspnea significantly impacts the quality of life of the affected patients and is a good predictor of morbidity and mortality. Chronic dyspnea is challenging, especially when the etiology is unclear. Performing pulmonary function tests (PFTs) and a cardiopulmonary exercise test (CPET) allows to better understand the pathophysiology of the dyspnea in order to guide the diagnosis.

La dyspnée est un symptôme qui résulte d'une interaction complexe entre de multiples mécanismes incomplètement élucidés à l'heure actuelle. Elle est fréquemment rencontrée en médecine de premier recours et elle est considérée comme chronique si elle dure plus d'un mois. Dans 85 % des cas, la cause est une pathologie cardiorespiratoire. Elle est à elle seule un prédicteur de morbidité et de mortalité important, impactant sensiblement la qualité de vie du patient. Les étiologies sont multiples. En cas de dyspnée chronique d'étiologie indéterminée, les explorations fonctionnelles respiratoires et un test d'effort cardiopulmonaire aident à une meilleure compréhension de la physiopathologie de la dyspnée et permettent ainsi d'affiner le diagnostic.

[Overlap syndrome in chronic obstructive pulmonary disease patient]. / Le syndrome d'overlap chez le patient BPCO.

Overlap syndrome (OVS) is defined by the co-existence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) in a same patient. This condition is associated with increased mortality and a higher risk of respiratory exacerbation, compared to patients with COPD or OSA alone. Nocturnal positive PAP treatment is effective to mitigate the additional risk related to OSA. Identification of OVS is a major challenge for clinicians because of the many phenotypes of OVS patients, with atypical OSA presentation, whose sleep quality is already impacted by COPD itself. Dedicated prospective studies are mandatory to improve our understanding of OVS patients and to optimize their medical care.

Le syndrome d'overlap (SOV) est défini par l'association d'une bronchopneumopathie chronique obstructive (BPCO) et d'un syndrome d'apnées obstructives du sommeil (SAOS). Il est associé à une mortalité et un risque d'exacerbation respiratoire augmentés, comparé à la BPCO ou au SAOS seuls. Un traitement par pression positive nocturne est efficace pour corriger le risque lié aux apnées du sommeil. L'identification du SOV est un défi pour le clinicien, en raison d'une importante hétérogénéité clinique, d'une présentation souvent frustre du SAOS chez le patient BPCO, dont la qualité du sommeil est déjà dégradée par la maladie elle-même. Des études prospectives dédiées sont nécessaires afin de préciser les phénotypes du SOV ainsi que la prise en charge diagnostique et thérapeutique de ces patients.

Modern Invasive Hemodynamic Assessment of Pulmonary Hypertension.

Since 1998 pulmonary hypertension has been clinically classified into five well-defined, distinct categories. A definitive diagnosis of pulmonary hypertension requires the invasive confirmation of an elevated mean pulmonary artery pressure of 25 mm Hg or above during a right heart catheterization. From a hemodynamic point of view, pulmonary hypertension is classified into precapillary and postcapillary pulmonary hypertension on the basis of a pulmonary artery wedge pressure threshold value of 15 mm Hg. Pulmonary vascular resistance is better characterized by multi-point pressure/flow measurements than by single-point determination. Multi-point pulmonary vascular resistance calculation could be useful for early disease identification as well as for treatment response assessment. Occlusion analysis of the pulmonary artery pressure decay curve after balloon inflation at the tip of the pulmonary artery catheter permits locating the site of predominantly increased resistance and could be useful in differentiating proximal from distal vasculopathy, especially in chronic thromboembolic pulmonary hypertension. The pulsatile hydraulic load of the pulmonary circulation can be better appreciated by pulmonary vascular impedance or via the resistance-compliance relationship than by means of pulmonary vascular resistance. Determination of right ventriculo-arterial coupling permits assessing the impact of an elevated afterload on right ventricular function, which ultimately determines the symptoms and prognosis of patients with pulmonary hypertension. The clinical utility of combining different invasive hemodynamic approaches is still uncertain and remains to be determined.

[Pulmonary rehabilitation in respiratory disorders other than COPD : an individualized approach]. / Réhabilitation pulmonaire lors de pathologies autres que la BPCO : un programme sur mesure.

Pulmonary rehabilitation is a multimodal intervention which includes an individualized physical training program, patient education, nutritional assessment and counseling, and recommendations for behavioral changes (smoking cessation, physical activity, nutrition...). This approach, validated and widely accepted by international expert societies in COPD, has been explored and evaluated in other chronic respiratory disorders. This overview analyses the impact of pulmonary rehabilitation in interstitial lung diseases, pulmonary hypertension, lung cancer (pre and post surgery), and morbid obesity. The recent medical literature encourages clinicians to consider the possibility of pulmonary rehabilitation in most chronic pulmonary disorders.

La réhabilitation respiratoire est une intervention multimodale comprenant un entraînement physique personnalisé, un enseignement thérapeutique, une prise en charge nutritionnelle, et un encouragement à des modifications comportementales. Cette approche, validée et recommandée par les sociétés savantes lors de BPCO, est de plus en plus étudiée dans d'autres pathologies pulmonaires chroniques. Ce travail analyse l'impact de la réhabilitation respiratoire lors de pneumopathies interstitielles, d'hypertension pulmonaire, d'obésité morbide et lors de cancer pulmonaire (en phase pré ou postopératoire). Les données les plus récentes encouragent les cliniciens à envisager systématiquement la possibilité d'une réhabilitation respiratoire lors de pathologies respiratoires chroniques.

Dynamics of the RR-interval versus blood pressure relationship at exercise onset in humans.

PURPOSE: The dynamics of the postulated phenomenon of exercise baroreflex resetting is poorly understood, but can be investigated using closed-loop procedures. To shed light on some mechanisms and temporal relationships participating in the resetting process, we studied the time course of the relationship between the R-R interval (RRi) and arterial pressure with a closed-loop approach. METHODS: On ten young volunteers at rest and during light exercise in supine and upright position, we continuously determined, on single-beat basis, RRi (electrocardiography), and arterial pressure (non-invasive finger pressure cuff). From pulse pressure profiles, we determined cardiac output (CO) by Modelflow, computed mean arterial pressure (MAP), and calculated total peripheral resistance (TPR). RESULTS: At exercise start, RRi was lower than in quiet rest. As exercise started, MAP fell to a minimum (MAPm) of 72.8 ± 9.6 mmHg upright and 73.9 ± 6.2 supine, while RRi dropped. The initial RRi versus MAP relationship was linear, with flatter slope than resting baroreflex sensitivity, in both postures. TPR fell and CO increased. After MAPm, RRi and MAP varied in opposite direction toward exercise steady state, with further CO increase. CONCLUSION: These results suggest that, initially, the MAP fall was corrected by a RRi reduction along a baroreflex curve, with lower sensitivity than at rest, but eventually in the same pressure range as at rest. After attainment of MAPm, a second phase started, where the postulated baroreflex resetting might have occurred. In conclusion, the change in baroreflex sensitivity and the resetting process are distinct phenomena, under different control systems.

Non-invasive diagnosis of pulmonary hypertension from lung Doppler signal: a proof of concept study.

Transthoracic Parametric Doppler (TPD) is a novel ultrasound technique recently developed for the investigation of pulmonary blood vessels. Lung Doppler Signals (LDS) recorded from TPD provide information regarding the functional mechanical characteristics of pulmonary blood vessels. We aimed to define the specific profile of LDS generated from TPD imaging in patients with pulmonary hypertension (PH), and to evaluate the diagnostic performance of LDS to detect PH using right heart catheterization (RHC) as gold standard reference. Seventy nine PH patients and 79 healthy controls matched for age, gender and BMI were recruited in a prospective case-control multicenter study. LDS recordings were performed by TPD consisting of a pulsed Doppler with a 2 MHz single element transducer. LDS were recorded within 24 h of RHC. Following LDS extraction, classification and performance evaluation were performed offline using a support vector machine (k-fold cross validation method). The best LDS parameters for PH detection were (1) peak velocity of the systolic (S) and diastolic (D) signals, (2) the rise slope of the S and D signals, and (3) time to peak of the S signal. Overall, the sensitivity and specificity of TPD for detection of PH were 82.7 % (95 % CI 81.3-84.1) and 87.4 % (95 % CI 86.3-88.5), respectively, with an area under the receiver operating curve of 0.95 (95 % CI 0.94-0.96). Detection rate of PH increased progressively with the level of mean pulmonary artery pressure. LDS recorded by TPD display a specific profile in PH and appears to be a promising and reliable tool for PH diagnosis. Further studies are required to confirm the clinical usefulness of LDS.

[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.

Resting pulmonary artery pressure of 21-24†mmHg predicts abnormal exercise haemodynamics.

A resting mean pulmonary artery pressure (mPAP) of 21-24 mmHg is above the upper limit of normal but does not reach criteria for the diagnosis of pulmonary hypertension (PH). We sought to determine whether an mPAP of 21-24 mmHg is associated with an increased risk of developing an abnormal pulmonary vascular response during exercise.Consecutive patients (n=290) with resting mPAP <25 mmHg who underwent invasive exercise haemodynamics were analysed. Risk factors for pulmonary vascular disease or left heart disease were present in 63.4% and 43.8% of subjects. An abnormal pulmonary vascular response (or exercise PH) was defined by mPAP >30 mmHg and total pulmonary vascular resistance >3 WU at maximal exercise.Exercise PH occurred in 74 (86.0%) out of 86 versus 96 (47.1%) out of 204 in the mPAP of 21-24 mmHg and mPAP <21 mmHg groups, respectively (OR 6.9, 95% CI: 3.6-13.6; p<0.0001). Patients with mPAP of 21-24 mmHg had lower 6-min walk distance (p=0.002) and higher New York Heart Association functional class status (p=0.03). Decreasing levels of mPAP were associated with a lower prevalence of exercise PH, which occurred in 60.3%, 38.7% and 7.7% of patients with mPAP of 17-20, 13-16 and <13 mmHg, respectively.In an at-risk population, a resting mPAP between 21-24 mmHg is closely associated with exercise PH together with worse functional capacity.

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.