The practical management of fluid retention in adults with right heart failure due to pulmonary arterial hypertension

Pulmonary hypertension and chronic kidney disease: prevalence, pathophysiology and outcomes

Pulmonary hypertension (PH) is common in patients with chronic kidney disease (CKD) or kidney failure, with an estimated prevalence of up to 78% in those referred for right-heart catheterization. PH is independently associated with adverse outcomes in CKD, raising the possibility that early detection and appropriate management of PH might improve outcomes in at-risk patients. Among patients with PH, the prevalence of CKD stages 3 and 4 is estimated to be as high as 36%, and CKD is also independently associated with adverse outcomes. However, the complex, heterogenous pathophysiology and clinical profile of CKD-PH requires further characterization. CKD is often associated with elevated left ventricular filling pressure and volume overload, which presumably leads to pulmonary vascular stiffening and post-capillary PH. By contrast, a distinct subgroup of patients at high risk is characterized by elevated pulmonary vascular resistance and right ventricular dysfunction in the absence of pulmonary venous hypertension, which may represent a right-sided cardiorenal syndrome defined in principle by hypervolaemia, salt avidity, low cardiac output and normal left ventricular function. Current understanding of CKD-PH is limited, despite its potentially important ramifications for clinical decision making. In particular, whether PH should be considered when determining the suitability and timing of kidney replacement therapy or kidney transplantation is unclear. More research is urgently needed to address these knowledge gaps and improve the outcomes of patients with or at risk of CKD-PH.

Perioperative Right Ventricular Dysfunction and Abnormalities of the Tricuspid Valve Apparatus in Patients Undergoing Cardiac Surgery

Right ventricular (RV) dysfunction frequently occurs after cardiac surgery and is linked to adverse postoperative outcomes, including mortality, reintubation, stroke, and prolonged ICU stays. While various criteria using echocardiography and hemodynamic parameters have been proposed, a consensus remains elusive. Distinctive RV anatomical features include its thin wall, which presents a triangular shape in a lateral view and a crescent shape in a cross-sectional view. Principal causes of RV dysfunction after cardiac surgery encompass ischemic reperfusion injury, prolonged ischemic time, choice of cardioplegia and its administration, cardiopulmonary bypass weaning characteristics, and preoperative risk factors. Post-left ventricular assist device (LVAD) implantation RV dysfunction is common but often transient, with a favorable prognosis upon resolution. There is an ongoing debate regarding the benefits of concomitant surgical repair of the RV in the presence of regurgitation. According to the literature, the gold standard techniques for assessing RV function are cardiac magnetic resonance imaging and hemodynamic assessment using thermodilution. Echocardiography is widely favored for perioperative RV function evaluation due to its accessibility, reproducibility, non-invasiveness, and cost-effectiveness. Although other techniques exist for RV function assessment, they are less common in clinical practice. Clinical management strategies focus on early detection and include intravenous drugs (inotropes and vasodilators), inhalation drugs (pulmonary vasodilators), ventilator strategies, volume management, and mechanical support. Bridging research gaps in this field is crucial to improving clinical outcomes associated with RV dysfunction in the near future.

Pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a rare and progressive disease characterised by remodelling of the pulmonary arteries and progressive narrowing of the pulmonary vasculature. This leads to a progressive increase in pulmonary vascular resistance and pulmonary arterial pressure and, if left untreated, to right ventricular failure and death. A correct diagnosis requires a complete work-up including right heart catheterisation performed in a specialised centre. Although our knowledge of the epidemiology, pathology and pathophysiology of the disease, as well as the development of innovative therapies, has progressed in recent decades, PAH remains a serious clinical condition. Current treatments for the disease target the three specific pathways of endothelial dysfunction that characterise PAH: the endothelin, nitric oxide and prostacyclin pathways. The current treatment algorithm is based on the assessment of severity using a multiparametric risk stratification approach at the time of diagnosis (baseline) and at regular follow-up visits. It recommends the initiation of combination therapy in PAH patients without cardiopulmonary comorbidities. The choice of therapy (dual or triple) depends on the initial severity of the condition. The main treatment goal is to achieve low-risk status. Further escalation of treatment is required if low-risk status is not achieved at subsequent follow-up assessments. In the most severe patients, who are already on maximal medical therapy, lung transplantation may be indicated. Recent advances in understanding the pathophysiology of the disease have led to the development of promising emerging therapies targeting dysfunctional pathways beyond endothelial dysfunction, including the TGF-β and PDGF pathways.

Pharmacological management of connective tissue disease-associated pulmonary arterial hypertension

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a severe, progressive pulmonary vasculopathy (Group 1 Pulmonary Hypertension (PH)) that complicates the course of many connective tissue diseases (CTD). Detailed testing is required to differentiate PAH from other types of PH caused by CTD such as left heart disease (Group 2 PH), pulmonary parenchymal disease (Group 3 PH), and chronic thromboembolic pulmonary hypertension (Group 4 PH). PAH is most frequently seen in systemic sclerosis but can also be seen with systemic lupus erythematosus, mixed CTD, and primary Sjogren's syndrome.

AREAS COVERED

This review discusses the epidemiology of CTD-associated PAH, outlines the complex diagnosis approach, and finishes with an in-depth discussion on the current treatment paradigm. Focus is placed on challenges faced in the treatment of CTD-associated PAH, (decreased efficacy and poorer tolerance of pharmacological therapies) and includes a discussion on the future investigational treatments.

EXPERT OPINION

Despite significant advances over the past decades with more aggressive treatment algorithms, CTD-associated PAH patients continue to have poorer survival compared to those with idiopathic PAH. This review highlights factors leading to disparate outcomes compared to other forms of PAH, and discusses on further improvements that may increase quality of life and survival for CTD-associated PAH patients.

Computer simulation of surgical interventions for the treatment of refractory pulmonary hypertension

This paper describes computer models of three interventions used for treating refractory pulmonary hypertension (RPH). These procedures create either an atrial septal defect, a ventricular septal defect or, in the case of a Potts shunt, a patent ductus arteriosus. The aim in all three cases is to generate a right-to-left shunt, allowing for either pressure or volume unloading of the right side of the heart in the setting of right ventricular failure, while maintaining cardiac output. These shunts are created, however, at the expense of introducing de-oxygenated blood into the systemic circulation, thereby lowering the systemic arterial oxygen saturation. The models developed in this paper are based on compartmental descriptions of human hemodynamics and oxygen transport. An important parameter included in our models is the cross-sectional area of the surgically created defect. Numerical simulations are performed to compare different interventions and various shunt sizes and to assess their impact on hemodynamic variables and oxygen saturations. We also create a model for exercise and use it to study exercise tolerance in simulated pre-intervention and post-intervention RPH patients.

Allgemeine Therapie der pulmonalarteriellen Hypertonie nach den neuen Leitlinien

In den neuen Leitlinien (LL) für pulmonalarterielle Hypertonie (PAH) sind die allgemeinen Maßnahmen ein integraler Bestandteil der Behandlung der Patienten. Auch die systemischen Auswirkungen der pulmonalen Hypertonie und Rechtsherzinsuffizienz sollten angemessen berücksichtigt und behandelt werden. Im folgenden Artikel werden die in den LL genannten Maßnahmen unter Berücksichtigung des bestehenden Empfehlungsgrads und der Evidenzen beschrieben. Leider sind die meisten Allgemeinmaßnahmen, wie die Gabe von Diuretika, Sauerstoff, psychosozialer Support und Impfungen, nicht oder unzureichend in randomisierten, kontrollierten Studien untersucht worden. So haben sie zwar einen hohen I-Empfehlungsgrad, aber einen niedrigen Evidenzgrad C. Nur bei dem spezialisierten körperlichen Training liegen bislang insgesamt 7 randomisierte, kontrollierte Studien und 5 Metaanalysen vor, die eine Verbesserung der Sauerstoffaufnahme, körperlichen Belastbarkeit, der Beschwerden (WHO-Funktionsklasse), Lebensqualität und Hämodynamik nachgewiesen haben (daher neu IA-Empfehlung). Auch weitere Maßnahmen wie die Antikoagulation, Eisensubstitution und andere werden im Folgenden besprochen.

Computational modelling of multi-temporal ventricular-vascular interactions during the progression of pulmonary arterial hypertension

A computational framework is developed to consider the concurrent growth and remodelling (G&R) processes occurring in the large pulmonary artery (PA) and right ventricle (RV), as well as ventricular-vascular interactions during the progression of pulmonary arterial hypertension (PAH). This computational framework couples the RV and the proximal PA in a closed-loop circulatory system that operates in a short timescale of a cardiac cycle, and evolves over a long timescale due to G&R processes in the PA and RV. The framework predicts changes in haemodynamics (e.g. 68.2% increase in mean PA pressure), RV geometry (e.g. 38% increase in RV end-diastolic volume) and PA tissue microstructure (e.g. 90% increase in collagen mass) that are consistent with clinical and experimental measurements of PAH. The framework also predicts that a reduction in RV contractility is associated with long-term RV chamber dilation, a common biomarker observed in the late-stage PAH. Sensitivity analyses on the G&R rate constants show that large PA stiffening (both short and long term) is affected by RV remodelling more than the reverse. This framework can serve as a foundation for the future development of a more predictive and comprehensive cardiovascular G&R model with realistic heart and vascular geometries.

Perioperative Management of Pulmonary Hypertension. a Review

Pulmonary hypertension is a rare and progressive pathology defined by abnormally high pulmonary artery pressure mediated by a diverse range of aetiologies. It affects up to twenty-six individuals per one million patients currently living in the United Kingdom (UK), with a median life expectancy of 2.8 years in idiopathic pulmonary hypertension. The diagnosis of pulmonary hypertension is often delayed due to the presentation of non-specific symptoms, leading to a delay in referral to specialists services. The complexity of treatment necessitates a multidisciplinary approach, underpinned by a diverse disease aetiology from managing the underlying disease process to novel specialist treatments. This has led to the formation of dedicated specialist treatment centres within centralised UK cities. The article aimed to provide a concise overview of pulmonary hypertension’s clinical perioperative management, including key definitions, epidemiology, pathophysiology, and risk stratification.

Diagnosis and Management of Failed Surgical Tricuspid Valve Annuloplasty

PURPOSE OF THE REVIEW

Annular-based strategies for treating tricuspid valve (TV) regurgitation do not always have satisfactory long-term outcomes. Management of failed TV annuloplasty can be challenging and requires a dedicated heart team approach. This review explores the treatment options available for failed TV annuloplasty.

RECENT FINDINGS

Recent developments and novel percutaneous treatment options have emerged as promising alternatives for patients with failed TV annuloplasty. Leaflet-based interventions, valve-in-valve procedures, transcatheter tricuspid valves and new-generation trans-caval valves are all feasible options, which can assure good results whilst minimizing risks for the patient. Failure of tricuspid annuloplasty is not uncommon amongst patients treated with either a tricuspid ring or suture-based device. The complex anatomy, physiology and clinical risk profile should be carefully evaluated on an individual patient-by-patient basis in order to select the most appropriate clinical and percutaneous treatment strategy. Different transcatheter tricuspid valve repair or replacement techniques may provide an attractive alternative treatment option for managing this challenging patient cohort.