[Tricuspid regurgitation: transcatheter treatment by TriClip®]. / Insuffisance tricuspide. Traitement transcathéter par TriClip®.

Tricuspid regurgitation (TR) is not rare and has been associated with poor clinical outcomes when severe. The etiology of TR is functional in most cases and is usually associated with left-sided valvular heart disease. Severe TR is responsible for right heart failure and may evolve to global heart failure. Current echocardiographic classification includes several grades (trivial, moderate, severe, massive, torrential TR) which influence patients' prognosis in an incremental manner. Management of patients with severe TR is discussed in Heart Team after evaluation of surgical risk. The TRI-SCORE may be used to evaluate the intra-hospital mortality risk in case of isolated tricuspid surgery. Isolated TR surgery is rarely performed as surgical risk outweighs expected clinical benefits. Transcatheter treatment of severe TR may be considered in highly selected cases. Transcatheter edge-to-edge repair (TEER) restores leaflets coaptation. First tricuspid TEER procedures were performed with the MitraClip® (Abbott, Santa Clara, CA, USA) device, but a specific device has been developed: the TriClip® (Abbott). The prospective multicenter TRILUMINATE trial evaluated the TriClip® procedure in patients with symptomatic moderate to severe TR and high surgical risk. The results show a good efficacy with reduction of post-procedural TR grade and increase in NYHA functional class, 6-minute walking test distance, right ventricular function, and quality of life at 1 year. Other devices are currently being evaluated or in development (i.e., transcatheter tricuspid implantation). Non-surgical TR management is likely to evolve and improve significantly soon.

L'insuffisance tricuspide (IT) est une valvulopathie assez fréquente dans la population et qui est associée à un mauvais pronostic lorsqu'elle est modérée à sévère. Elle est le plus souvent fonctionnelle et liée à une valvulopathie du cœur gauche. Cliniquement, elle se marque par le développement de signes d'insuffisance cardiaque droite avec évolution vers une décompensation cardiaque globale. La classification échocardiographique actuelle distingue plusieurs stades (IT minime, modérée, sévère, massive et torrentielle) qui influencent le pronostic de façon incrémentielle. La prise en charge est discutée de manière collégiale après stratification du risque opératoire, dont l'évaluation est facilitée par le TRI-SCORE (risque de mortalité intra-hospitalière post-opératoire de chirurgie isolée de la valve tricuspide). La prise en charge chirurgicale d'une IT isolée est rarement pratiquée en raison d'un risque opératoire souvent élevé. Une prise en charge percutanée peut être envisagée dans certains cas, selon les limitations anatomiques. La technique de réparation bord à bord au niveau tricuspidien permet de restaurer une coaptation valvulaire par accolement des feuillets. Initialement réalisée à l'aide du système MitraClip® (Abbott, Santa Clara, CA, USA), il existe maintenant un système dédié spécifiquement à la tricuspide : le TriClip® (Abbott), dont la dernière génération existe en quatre tailles. Le TriClip® a été évalué dans l'étude prospective multicentrique TRILUMINATE chez des patients avec IT modérée à sévère symptomatique à haut risque chirurgical. La procédure a montré une efficacité avec réduction rapide du grade d'IT et amélioration de la classe fonctionnelle NYHA, de la distance de marche à 6 minutes, de la fonction ventriculaire droite et de la qualité de vie à un an. D'autres dispositifs sont en cours d'étude ou en développement (implantation tricuspide percutanée). La prise en charge non chirurgicale de l'IT devrait se développer de manière significative dans le futur.

[First report in the Liege province (Belgium) of a concomitant aortic and mitral valve surgery via a minimally invasive right latero-thoracic approach]. / Double chirurgie mitrale et aortique par abord mini-invasif latéral thoracique droit : à propos d'une première liégeoise.

Compared to median sternotomy, the potential benefits of minimally invasive single aortic or mitral valve surgery include reduction of blood loss, lower morbidity, and shorter intensive care unit and hospital length of stay. However, there are few reports regarding concomitant aortic and mitral valves minimally invasive surgery via mini-thoracotomy. To the authors knowledge, this is the first report in the Liege area, of a successful minimally invasive right latero-thoracic approach for aortic and mitral valve surgery in a 78-year old woman who presented severe and symptomatic aortic stenosis and mitral insufficiency. In addition to the description of the surgical approach, the authors will summarize the current literature on this approach, as well as the clinical evolution of the patient.

La chirurgie valvulaire isolée, aortique ou mitrale par voie mini-invasive offre de nombreux avantages par rapport à la sternotomie médiane en termes de réduction des pertes sanguines, de diminution de la morbidité et de réduction des durées de séjour aux soins intensifs et hospitalier global. Toutefois, il existe très peu de données dans la littérature sur la chirurgie combinée mitrale et aortique par mini-thoracotomie. à notre connaissance, nous présentons le premier cas de double chirurgie mitrale et aortique réalisée avec succès par abord latéral thoracique droit dans la région liégeoise chez une patiente de 78 ans qui présentait une sténose aortique et une insuffisance mitrale sévères et symptomatiques. En plus d'une description de notre technique chirurgicale, nous résumerons les grandes séries cliniques publiées dans la littérature sur le sujet, ainsi que l'évolution clinique de notre patiente.

[Organ transplantation during SARS-CoV-2 epidemic : the 2020-2021 Liege transplant Center experience]. / Face à la COVID-19. La transplantation d'organes en période de pandémie SARS-CoV-2 : l'expérience 2020-2021 du Centre liégeois de Transplantation.

The «Severe Acute Respiratory Syndrome coronavirus 2¼ (SARS-CoV-2) pandemic has disrupted medical care and intra-hospital organization during 2020, both in Belgium and throughout the world. Solid organ transplantation was not spared and in Belgium, the number of organ donors and transplants overall decreased by 20 % for livers and by 33 % for hearts between 2019 and 2020. The aim of this article is to summarize the experience acquired in 2020 and 2021 on the organizational and medical implications of the coronavirus disease 2019 (COVID-19) pandemic with regard to the care of patients transplanted or awaiting for organ transplants, and to draw conclusions both for the aftermath of COVID-19 but also for future pandemics. Vaccination against SARS-CoV-2 is highly recommended and particularly important in organ transplant recipients, even if the response rate is lower than in the non-transplanted population. A third injection is now advised in immunosuppressed patients.

La pandémie de «Severe Acute Respiratory Syndrome coronavirus 2¼ (SARS-CoV-2) a bouleversé les soins médicaux et l'organisation intra-hospitalière durant l'année 2020 en Belgique et dans le monde. La transplantation d'organes ne fut pas épargnée. En Belgique, le nombre de donneurs d'organes et de transplantations a globalement diminué de 20 % pour les foies et de 33 % pour les cœurs entre 2019 et 2020. Le but de cet article est de résumer l'expérience acquise en 2020 et 2021 sur les implications organisationnelles et médicales de la pandémie de «coronavirus disease 2019¼ (COVID-19) quant à la prise en charge des patients transplantés ou en attente de greffe d'organes, et d'en tirer les conclusions à la fois pour les suites de la COVID-19, mais aussi pour les éventuelles futures pandémies. La vaccination anti-SARS-CoV-2 est recommandée et particulièrement importante chez les patients transplantés d'organe, même si le taux de réponse est inférieur à la population non transplantée. Une troisième injection est conseillée chez les patients immunodéprimés.

[The opportunities of the minimally invasive approach for the cardiovascular and thoracic surgery]. / Apport de l'approche moins invasive en chirurgie cardiovasculaire et thoracique.

There is a continuous growth in the incidence of cardiovascular and thoracic diseases, especially related to the increased life expectancy. Moreover, the quality and efficacy of care for these pathologies are progressing constantly. The evolution of surgery prompts us to develop less aggressive (minimally invasive), although technically more complex, treatment or diagnostic techniques. Pathologies, which until now required heavy surgeries, are managed today in a less invasive way and become therefore accessible to patients even if they are older or in a poor general condition. In this article, we present our experience in the development of the minimal invasive procedures in cardiovascular and thoracic surgery.

Les pathologies cardiovasculaires et thoraciques, au sens large, sont de plus en plus fréquentes, vu l'augmentation de l'espérance de vie, mais elles sont aussi de mieux en mieux prises en charge. En effet, l'évolution de la chirurgie nous incite à développer des techniques de traitement ou de diagnostic moins agressives (mini-invasives) quoique techniquement plus complexes. Des pathologies qui nécessitaient, jusqu'à présent, des chirurgies lourdes se prennent en charge, aujourd'hui, de manière moins invasive et deviennent donc accessibles à des patients en moins bon état général ou de plus en plus âgés. Nous présentons ici notre expérience dans le développement de l'approche mini-invasive en chirurgie cardiovasculaire et thoracique.

[Heart transplantation, indications and results at the University Hospital of Liege]. / La transplantation cardiaque : indications actuelles et résultats de l'expérience liégeoise.

Heart transplantation remains undoubtedly the most effective treatment for end-stage heart failure, whatever its cause. Last decade has witnessed significant improvements in terms of morbidity and mortality following heart transplant. The 5-year survival rate is now beyond 70 %. However, the shortage of potential donors limits its use and requires strict criteria before listing a candidate for heart transplantation. Herein, we present a review of current indications and results of the heart transplantation program at the University hospital of Liège.

La transplantation cardiaque demeure, à ce jour sans conteste, le traitement de choix de l'insuffisance cardiaque terminale, quelle qu'en soit l'origine. La dernière décennie a été marquée par une amélioration significative des résultats de la transplantation cardiaque tant en termes de mortalité que de morbidité. La survie globale à 5 ans dépasse maintenant 70 %. Cependant, la pénurie d'organes limite malheureusement son emploi et impose des critères de sélection rigoureux des potentiels candidats. Une revue des indications actuelles ainsi qu'un aperçu des résultats de la transplantation cardiaque au CHU de Liège sont présentés.

[Minimally invasive aortic valve replacement through right anterior minithoracotomy: early experience at the University Hospital of Liege]. / Chirurgie valvulaire aortique mini-invasive vidéo-assistée par thoracotomie. Expérience initiale liégeoise.

Aortic valve replacement is nowadays a safe procedure with low morbidity and mortality. However, the evolution of surgery requires the development of less invasive techniques. Aortic valve replacement through a right mini-thoracotomy, technically more complicated, offers a lower rate of complications including less postoperative pain and less blood loss and transfusion, with a faster recovery. We report our early experience of aortic valve replacement through a right anterior mini-thoracotomy.

La chirurgie de remplacement valvulaire aortique offre toujours d'excellents résultats avec une morbidité et une mortalité faibles. Cependant, l'évolution de la chirurgie nous incite à développer des techniques mini-invasives. La mini-thoracotomie antérieure droite, pour la chirurgie de remplacement de la valve aortique, techniquement plus complexe, offre de nombreux avantages. Cette technique assure une réduction des pertes sanguines et des douleurs postopératoires, une meilleure fonction respiratoire, un rétablissement plus rapide (durée de séjour hospitalier plus court) et un bénéfice esthétique. Nous rapportons ici notre expérience initiale de remplacement valvulaire aortique par mini-thoracotomie antérieure droite.

[Ruptured abdominal aortic aneurysm]. / L'anévrisme rompu de l'aorte abdominale.

Ruptured abdominal aortic aneurysm is a cardiovascular emergency associated with a 30 day mortality as high as 70 %. However, recent progresses in the management of these patients have improved the results. From a surgical point of view, endovascular methods such as balloon occlusion and endovascular repair (EVAR) in patients with suitable anatomy are recommended in order to reduce mortality.

isme rompu de l'aorte abdominale constitue une urgence cardiovasculaire qui s'accompagne d'un taux de mortalité globale pouvant atteindre 70 % à 30 jours. Cependant, les progrès récents dans la prise en charge de ces patients ont permis d'améliorer les résultats. Du point de vue chirurgical, des techniques endovasculaires telles que l'endoclampage et la mise en place d'endoprothèses en cas d'anatomie favorable, sont de plus en plus recommandées afin de diminuer la mortalité.

[Aortic dissection]. / La dissection aortique.

Aortic dissection is a life-threatening condition due to a tear in the intimal layer of the aorta or bleeding within the aortic wall, resulting in the separation of the different layers of the aortic wall. Among the risk factors, age, hypertension, dyslipidemia and genetic disorders of the connective tissue have been identified. A prompt diagnosis and an adequate treatment are important in the management of affected patients. The type of treatment depends on the location and extension of the dissection. Open surgical repair is most commonly used for dissections involving the ascending aorta and the aortic arch, whereas endovascular intervention is indicated for descending aorta dissections that are complicated. In this paper, we will review the epidemiology, and physiopathology of aortic dissection and describe the appropriate management for each type of dissection (open surgery, endovascular or medical treatment).

La dissection aortique est une pathologie grave et potentiellement mortelle. Elle résulte d'une déchirure intimale ou d'un saignement dans la paroi aortique, qui entraîne une séparation au sein des différentes couches de cette dernière. Parmi les facteurs de risque de cette pathologie, citons l'âge, l'hypertension artérielle, la dyslipidémie, et les atteintes génétiques du tissu conjonctif. Un diagnostic précis et une prise en charge adéquate et rapide sont déterminants dans le management des patients. Le type de traitement est conditionné par la localisation et l'extension de la dissection. La chirurgie ouverte est généralement indiquée dans les atteintes de l'aorte ascendante et de l'arche aortique, tandis que l'approche endovasculaire sera privilégiée dans les dissections de l'aorte thoracique descendante compliquées. Dans cet article, nous ferons un rappel succinct de l'épidémiologie et de la physiopathologie des dissections aortiques, puis nous décrirons la prise en charge médicale, chirurgicale ouverte et endovasculaire.

[Minimally invasive aortic valve surgery. Experience of the academic hospital of Liege and review of the literature]. / Chirurgie «mini-invasive¼ de la valvule aortique. Expérience du CHU de Liège et revue de la littérature.

Minimally invasive aortic valve surgery aims at reducing surgical invasiveness whilst preserving the high efficacy of surgical aortic valve replacement. As such it increases the value of the overall procedure. The surgical experience at the ULg is reported and replaced in the context of the pertinent related litterature.

La réalisation de la chirurgie de la valve aortique par une voie d'abord réduite atténue le traumatisme chirurgical subi par le patient, mais doit garantir un geste de qualité équivalente. Au travers de la présentation d'une histoire clinique inscrite dans la routine, nous rapportons l'expérience du service dans ce domaine et nous la confrontons aux données de la littérature. L'approche mini-invasive apporte des avantages supplémentaires par rapport à la chirurgie conventionnelle et s'inscrit dans l'évolution actuelle des procédures interventionnelles.

Veno-venous extracorporeal CO2 removal improves pulmonary hemodynamics in a porcine ARDS model.

BACKGROUND: Protective lung ventilation is recommended in patients with acute respiratory distress syndrome (ARDS) to minimize additional injuries to the lung. However, hypercapnic acidosis resulting from ventilation at lower tidal volume enhances pulmonary hypertension and might induce right ventricular (RV) failure. We investigated if extracorporeal veno-venous CO2 removal therapy could have beneficial effects on pulmonary circulation and RV function. METHODS: This study was performed on an experimental model of ARDS obtained in eight anaesthetized pigs connected to a volume-cycled ventilator. A micromanometer-tipped catheter was inserted into the main pulmonary artery and an admittance micromanometer-tipped catheter was inserted into the right ventricle. RV-arterial coupling was derived from RV pressure-volume loops. ARDS was obtained by repeated bronchoalveolar lavage. Protective ventilation was then achieved, and the pigs were connected to a pump-driven extracorporeal membrane oxygenator (PALP, Maquet, Germany) in order to achieve CO2 removal. RESULTS: ARDS induced severe hypercapnic acidosis. Systolic pulmonary artery pressure significantly increased from 29.6±1.8 to 43.9±2.0 mmHg (P<0.001). After the PALP was started, acidosis was corrected and normocarbia was maintained despite protective ventilation. Pulmonary artery pressure significantly decreased to 31.6±3.2 mmHg (P<0.001) and RV-arterial coupling significantly improved (RV-arterial coupling index=1.03±0.33 vs. 0.55±0.41, P<0.05). CONCLUSION: Veno-venous CO2 removal therapy enabled protective ventilation while maintaining normocarbia during ARDS. CO2 removal decreased pulmonary hypertension and improved RV function. This technique may be an effective lung- and RV-protective adjunct to mechanical ventilation.

Alteration of left ventriculo-arterial coupling and mechanical efficiency during acute myocardial ischemia.

AIM: Myocardial revascularisation being frequently performed during acute myocardial ischemia, in a hostile hemodynamic environment, we evaluated left ventriculo-arterial (VA) coupling, left ventricular (LV) mechanical efficiency, and the mechanical properties of the systemic vasculature during acute myocardial ischemia. METHODS: In 6 pigs, vascular properties [characteristic impedance (R(1)), peripheral resistance (R(2)), compliance (C), inductance (L), arterial elastance (E(a))] were estimated with a windkessel model. LV function was assessed by the slope (E(es)) of end-systolic pressure-volume relationship (ESPVR), and stroke work (SW) - end-diastolic volume (EDV) relation. Pressure-volume area (PVA) was referred to as myocardial oxygen consumption. VA coupling was defined as E(es)/E(a), and mechanical efficiency as SW/PVA. After baseline recordings, the left anterior descending coronary artery was ligated and hemodynamic measures obtained every 30 minutes for 3 hours. Data are expressed as mean (SEM). RESULTS: Coronary occlusion induced an ESPVR rightward shift, and decreased E(es) from 3.67 (0.33) to 1.92 (0.20) mmHg/ml and the slope of the SW - EDV relationship from 72.3 (3.4) to 40.4 (4.5) mmHg (p<0.001), while E(a) increased from 3.33 (0.56) to 4.65 (0.29) mmHg/ml (p<0.005). This was responsible for a dramatic alteration of VA coupling from 1.22 (0.11) to 0.44 (0.07), (p<0.001). While R2 increased from 1.72 (0.30) to 2.38 (0.16) mmHg x s x ml(-1) (p<0.05) and C decreased from 0.78 (0.16) to 0.46 (0.08) ml/mmHg (p<0.05), R(1) and L were unchanged. Coronary occlusion decreased SW from 4056 (223) to 2580 (122) mmHg.ml (p<0.001), while PVA and SW/PVA decreased from 5575 (514) to 4813 (317) mmHg x ml (NS), and from 0.76 (0.04) to 0.57 (0.03) (p<0.001), respectively. CONCLUSION: Acute myocardial ischemia severely altered left ventriculo-arterial coupling and LV mechanical efficiency. Impaired left VA coupling was due to a combination of augmented arterial elastance, secondary to early vasoconstriction later associated with decreased arterial compliance, and decreased LV contractility.

Effects of U-46619 on pulmonary hemodynamics before and after administration of BM-573, a novel thromboxane A2 inhibitor.

We studied the effects on pulmonary hemodynamics of U-46619, a thromboxane A2 (TXA2) agonist, before and after administration of a novel TXA2 receptor antagonist and synthase inhibitor (BM-573). Six anesthetized pigs (Ago group) received 6 consecutive injections of U-46619 at 30-min interval and were compared with six anesthetized pigs (Anta group) which received an increasing dosage regimen of BM-573 10 min before each U-46619 injection. Consecutive changes in pulmonary hemodynamics, including characteristic resistance, vascular compliance, and peripheral vascular resistance, were continuously assessed during the experimental protocol using a four-element Windkessel model. At 2 mg/kg, BM-573 completely blocked pulmonary hypertensive effects of U-46619 but pulmonary vascular compliance still decreased. This residual effect can probably be explained by a persistent increase in the tonus of the pulmonary vascular wall smooth muscles sufficient to decrease vascular compliance but not vessel lumen diameter. Such molecule could be a promising therapeutic approach in TXA2 mediated pulmonary hypertension as it is the case in pulmonary embolism, hyperacute lung rejection and endotoxinic shock.

Effects of BM-573, a novel thromboxane A2 inhibitor, on pulmonary hemodynamics in endotoxic shock.

Thromboxane A2 is considered to be partially responsible for the increase in pulmonary vascular resistance observed after endotoxin administration and to participate in proinflammatory reactions. The effects of a novel dual TXA2 synthase inhibitor and TXA2 receptor antagonist (BM-573) on pulmonary hemodynamics were investigated in endotoxic shock. 30 mins before the start of a 0.5 mg/kg endotoxin infusion, 6 pigs (Endo group) received a placebo infusion and 6 other pigs (Anta group) received a BM-573 infusion. In Endo group, pulmonary artery pressure increased from 25 +/- 1.8 (T0) to 42 +/- 2.3 mmHg (T60) (p < 0.05) after endotoxin infusion while, in Anta group, it increased from 23 +/- 1.6 (T0) to 25 +/- 1.5 mmHg (T60). This difference is due to a reduction in pulmonary vascular resistance in Anta group while pulmonary arterial compliance changes in Endo group remained comparable with the evolution in Anta group. In Endo group, PaO2 decreased from 131 +/- 21 (T0) to 74 +/- 12 mmHg (T300) (p < 0.05), while in Anta group, PaO2 was 241 +/- 31 mmHg at the end of the experimental period (T300). These results demonstrate that TXA2 plays a major role in pulmonary vascular changes during endotoxin insult. Concomitant inhibition of TXA2 synthesis and of TXA2 receptors by BM-573 inhibited the pulmonary vasopressive response during the early phase of endotoxin shock as well as the deterioration in arterial oxygenation.

[Clinical case of the month. Type A aortic dissection after valve replacement]. / Le cas clinique du mois. Dissection aortique de type A post-remplacement valvulaire aortique.

The risk for aortic dissection or further dilation of the ascending aorta exists after aortic valve replacement. We present a case of acute aortic dissection following replacement of the aortic valve. The management and treatment of dilated ascending aorta associated with aortic valve disease are reviewed and discussed.

BM-573, a dual thromboxane synthase inhibitor and thromboxane receptor antagonist, prevents pig myocardial infarction induced by coronary thrombosis.

The aim of this study was to characterize the effects of BM-573 [N-terbutyl-N'-[2-(4'-methylphenylamino)-5-nitro-benzenesulfonyl] urea], a novel dual thromboxane A2 receptor antagonist and thromboxane synthase inhibitor, on myocardial infarction induced by topical ferric chloride (FeCl3) application to the left anterior descending (LAD) coronary artery in anesthetized pigs. All control animals (n = 6) developed an occlusive thrombus in the LAD coronary artery. The mean infarct size, revealed by triphenyl tetrazolium chloride (TTC), and the area at risk, evidenced by Evans blue, corresponded to 35.3 +/- 2.2 and 36.9 +/- 2.1% of the left ventricular mass, respectively. In the BM-573-treated group (n = 6), a drug infusion (10 mg. kg-1. h-1) started 30 min before FeCl3 application and continued throughout the experimentation. Among the BM-573-treated group, four pigs did not develop coronary artery thrombus and their myocardium appeared healthy. Histopathological examination of FeCl3-injured coronary artery revealed an occlusive and adherent thrombus in control group, while pretreatment with BM-573 prevented thrombus formation. In infarcted zones, lack of desmin staining and muscle structure disorganization were obvious. Depletion of myocardial ATP content was observed in the myocardial necrotic region of the control group, but not in myocardial samples of BM-573-treated pigs that did not develop myocardial infarction. When BM-573 prevented LAD artery occlusion, the area under the curve of plasmatic troponin T was reduced by 77% over 6 h. These data suggest that BM-573 could be useful for the prevention of myocardial infarction.

Effect of hemodiafiltration on pulmonary hemodynamics in endotoxic shock.

Hemofiltration can improve pulmonary hemodynamics during septic shock. The main objective of the study was to determine whether hemodiafiltration (HDF) would also have beneficial effects on pulmonary hemodynamics during septic shock. In the Endo group, six anesthetized pigs received a 0.5 mg/kg endotoxin infusion over 30 min. In the HDF group (n = 6), HDF was started 30 min after the end of the endotoxin infusion, while in the Control group (n = 4) they received HDF but no endotoxin infusion. Pulmonary hemodynamics were analyzed in detail with a four-element windkessel model. Although in the Control group, HDF did not alter pulmonary hemodynamic parameters, in the HDF group, it was responsible for an amplification of the deleterious pulmonary vascular response to endotoxin insult. Our results show that HDF must be used cautiously in septic shock since it can precipitate right heart failure by increasing pulmonary vascular resistance.