Right ventricle-pulmonary artery coupling in pulmonary artery hypertension its measurement and pharmacotherapy

TOWARDS A UNIVERSAL DEFINITION FOR RIGHT HEART FAILURE:A WORK IN PROGRESS

BACKGROUND

Broadly speaking, right heart failure can be defined as a clinical syndrome with signs and symptoms of heart failure resulting from right ventricular dysfunction, as evidenced by abnormal structure or function. The heterogeneity of conditions associated with right heart failure combined with the challenges of characterizing the structural and functional relationships of the right ventricle make a singular definition of right heart failure elusive. We performed a concise scoping review of the literature that provides knowledge synthesis of right heart failure in different clinical populations, and extracted the recommended criteria to define the syndrome.

METHODS

Searches were conducted to identify reviews, guidelines, consensus statements, systematic reviews, meta-analysis and consensus statements concerning right heart or right ventricular failure in well described adult human disease populations from the previous 10 years. After removal of case reports and duplicates, publications describing syndromes in the context of left sided heart disease were also removed. Data extracted from selected manuscripts included the patient population and quantitative criteria to define right heart failure, categorized based on diagnostic modalities.

RESULTS

Of 9487 articles initially identified, 71 were selected for full text review. We found that the majority of the reviewed literature offered multi-faceted diagnostic approaches, including clinical, echocardiographic, hemodynamic and therapeutic characteristics, with unique additions or omissions depending on the clinical contexts. Nomenclature for right heart failure was variable and only 40% of articles articulated a narrative definition.

CONCLUSION

At this time, development of consistent criteria and a universal definition for right heart failure remains a work in process.

A review regarding the article `Right heart catheterization in idiopathic pulmonary hypertension: An all-inclusive necessity'

Right heart catheterization (RHC) stands as a unique tool for both diagnosing and managing a broad spectrum of cardiovascular diseases. Though its origins trace back to the 18th century, the most substantial progress was achieved in the 20th century. The focus of this review is on pulmonary hypertension (PH), where RHC is recognized as the diagnostic gold standard. Parameters derived from this procedure are crucial for classifying PH into various subgroups, assessing the risk of adverse events or mortality, and informing treatment strategies. The European Society of Cardiology guidelines define PH as an increase in mean pulmonary artery pressure (PAPm) greater than 25 mmHg. The differentiation between pre- and post-capillary PH is based on the levels of pulmonary artery wedge pressure (PAWP). Furthermore, right atrial pressure (RAP), cardiac index (CI), and mixed venous oxygen saturation (SvO2) are the sole parameters recommended for prognostic assessment, specifically in patients with pulmonary arterial hypertension (PAH). Patients presenting with RAP exceeding 14 mmHg, CI less than 2.0 L/min/m2, and SvO2 below 60% are considered to be at a high risk (greater than 10%) of death within the subsequent year. A primary goal in the management of PAH is the early diagnosis to facilitate the swift initiation of treatment. This aims to minimize symptom burden, optimize the patient's biochemical, hemodynamic, and functional profile, and curtail adverse events. To achieve these objectives, clinicians must remain informed about emerging risk factors and be familiar with the revised hemodynamic definition for PAH.

A review regarding the article 'Effectiveness of mechanical circulatory support devices in reversing pulmonary hypertension among heart transplant candidates: A systematic review.'

Pulmonary hypertension (PH) with high pulmonary vascular resistance (PVR) is a very often diagnosed contraindication for orthotopic heart transplantation (OHT). It is a direct consequence of left ventricle failure characterized by high diastolic pressure obstructing the collection of blood from the pulmonary vessels. The occurrence of this situation grows with the increasing time of waiting for OHT, and with the progression of heart failure. Mechanical circulatory support (MCS) devices, particularly left ventricular assist devices (LVADs), have emerged as pivotal interventions for patients with fixed PH, offering a potential bridge to transplantation. The pathophysiological impact of PH in heart transplant candidates is profound, as it is associated with increased perioperative risk and heightened mortality post-transplantation. The selection of heart transplant candidates thus mandates a careful evaluation of PH, with an emphasis on distinguishing between reversible and fixed forms of the condition. Reversible PH can often be managed with medical therapies; however, fixed PH presents a more daunting challenge, necessitating more aggressive interventions like MCS. Patients are supported with LVADs until evidence of pulmonary afterload reversal is evident and then can be considered for heart transplantation. However, in those who are non-responders or have complications while being supported, their option for transplant is revoked. Despite these advancements, the heterogeneity of MCS devices and their mechanisms of action necessitates a nuanced understanding of their efficacy.

A review regarding the article 'Impact of tricuspid regurgitation severity on mortality in pulmonary hypertension patients: A comprehensive analysis

Pulmonary hypertension (PH) presents as a complex hemodynamic and pathophysiologic state present in many cardiovascular, respiratory, and systemic diseases. PH is considered to have a higher risk of cardiovascular events and mortality. The most common type of functional tricuspid regurgitation (TR) is associated with PH. Secondary TR, resulting not from intrinsic valvular pathology but from distortion of the valve apparatus due to right ventricular remodeling and dilation, is commonly seen in the setting of PH. It has been increasingly recognized as not merely a bystander but a significant contributor to the worsening of symptoms and decline in functional status. However, the extent to which TR impacts the clinical course and mortality in PH remains a subject of active investigation. The simultaneous presence of PH and secondary tricuspid regurgitation (STR) portends particularly poor outcomes. However, not all patients with PH develop significant TR, and the mechanisms and clinical implications underlying this phenomenon remain unclear. TR is a highly prevalent echocardiographic finding in the general population. Historically considered as the "forgotten valve disease" by clinicians and interventional cardiologists, TR has become a hot topic in cardiovascular interventions over recent years. If left untreated until severe, as often occurs, TR correlates with consistent morbidity and mortality, and a variety of surgical and percutaneous treatments have therefore been proposed. Mortality from isolated surgical repair of TR remains higher than that from surgery of any other valve insufficiency and a large number of patients are often deemed not eligible for surgical repair.