Treatment of right ventricular dysfunction and heart failure in pulmonary arterial hypertension

Right ventricular dyssynchrony for the prediction of prognosis in patients with systemic lupus erythematosus-aaociated pulmonary arterial hypertension: a study with two-dimensional speckle tracking

Pulmonary arterial hypertension (PAH) is a common complication of systemic lupus erythematosus (SLE), and PAH can cause right ventricle (RV) remodel and dyssynchrony. The aim of this study was to explore the value of RV dyssynchrony in predicting adverse clinical events in patients with systemic lupus erythematosus-aaociated pulmonary arterial hypertension (SLE-PAH) using two-dimensional speckle tracking echocardiography (2D-STE). A total of 53 patients with SLE-PAH were enrolled in this study. The dyssynchrony of the RV (RV-SD6) was evaluated by 2D-STE. The clinical data of all participants were collected, and routine cardiac function parameters were measured by two-dimensional echocardiography, and analyzed for their correlation with RV-SD6. The predictive value of RV-SD6 in clinical adverse event was evaluated. RV-SD6 was negatively correlated with RV-FLS, RV-FAC, and TAPSE (r = - 0.788, r = - 0.363 and r = - 0.325, respectively, all P < 0.01), while the correlation with RV-FLS was the strongest. linear regression analysis showed that RV-FLS was an independent risk factor for RV-SD6 (β = - 1.40, 95% CI - 1.65 ~ - 1.14, P < 0.001). Cox regression analysis showed that RV-SD6 was a predictor with clinical adverse events (HR = 1.03, 95% CI 1 ~ 1.06, P < 0.05). RV-SD6 was highly discriminative in predicting clinical adverse events (AUC = 0.764), at a cutoff of 51.10 ms with a sensitivity of 83.3% and specificity of 68.3%. RV-FLS was negatively correlated with RV-SD6 and was an independent risk factor for it. RV-SD6 can serve as an indicator for predicting the occurrence of adverse clinical events in SLE-PAH patients, with high sensitivity and specificity.

Blockage of the adenosine A2B receptor prevents cardiac fibroblasts overgrowth in rats with pulmonary arterial hypertension

Sustained pressure overload and fibrosis of the right ventricle (RV) are the leading causes of mortality in pulmonary arterial hypertension (PAH). Although the role of adenosine in PAH has been attributed to the control of pulmonary vascular tone, cardiac reserve, and inflammatory processes, the involvement of the nucleoside in RV remodelling remains poorly understood. Conflicting results exist on targeting the low-affinity adenosine A2B receptor (A2BAR) for the treatment of PAH mostly because it displays dual roles in acute vs. chronic lung diseases. Herein, we investigated the role of the A2BAR in the viability/proliferation and collagen production by cardiac fibroblasts (CFs) isolated from RVs of rats with monocrotaline (MCT)-induced PAH. CFs from MCT-treated rats display higher cell viability/proliferation capacity and overexpress A2BAR compared to the cells from healthy littermates. The enzymatically stable adenosine analogue, 5'-N-ethylcarboxamidoadenosine (NECA, 1-30 μM), concentration-dependently increased growth, and type I collagen production by CFs originated from control and PAH rats, but its effects were more prominent in cells from rats with PAH. Blockage of the A2BAR with PSB603 (100 nM), but not of the A2AAR with SCH442416 (100 nM), attenuated the proliferative effect of NECA in CFs from PAH rats. The A2AAR agonist, CGS21680 (3 and 10 nM), was virtually devoid of effect. Overall, data suggest that adenosine signalling via A2BAR may contribute to RV overgrowth secondary to PAH. Therefore, blockage of the A2AAR may be a valuable therapeutic alternative to mitigate cardiac remodelling and prevent right heart failure in PAH patients.

The association of Pulmonary Hypertension and right ventricular systolic function - updates in diagnosis and treatment

Right ventricular (RV) systolic function is an essential but neglected component in cardiac evaluation, and its importance to the contribution to overall cardiac function is undermined. It is not only sensitive to the effect of left heart valve disease but is also more sensitive to changes in pressure overload than the left ventricle. Pulmonary Hypertension is the common and well-recognized complication of RV systolic dysfunction. It is also the leading cause of pulmonary valve disease and right ventricular dysfunction. Patients with a high pulmonary artery pressure (PAP) and a low RV ejection fraction have a seven-fold higher risk of death than heart failure patients with a normal PAP and RV ejection fraction. Furthermore, it is an independent predictor of survival in these patients. In this review, we examine the association of right ventricular systolic function with Pulmonary Hypertension by focusing on various pathological and clinical manifestations while assessing their impact. We also explore new 2022 ESC/ERS guidelines for diagnosing and treating right ventricular dysfunction in Pulmonary Hypertension.

Intravenous Diuresis in Severe Precapillary Pulmonary-Hypertension-Related Right Heart Failure: Effects on Renal Function and Blood Pressure

In patients with right heart failure (RHF) and pulmonary hypertension (PH), classical teaching often advises cautious diuresis in the setting of 'preload dependence' to avoid renal injury and hemodynamic compromise. However, while this physiology may hold true in some clinical settings, such as acute ischemia with right ventricular infarction, it cannot necessarily be extended to PH-related RHF. Rather, in patients with precapillary PH and decompensated RHF, diuresis aimed to decongest the right heart and systemic venous system may be directly beneficial. This study aimed to evaluate the effects of diuresis on renal function and blood pressure in patients with severe precapillary PH. A retrospective chart review was conducted on 62 patients with severe precapillary PH admitted for decompensated RHF. The hemodynamic phenotype of these patients was characterized by invasive hemodynamics and echocardiographic data. Laboratory and hemodynamic data were collected at both admission and discharge. After large-volume diuresis in this patient population, there was an improvement in both glomerular filtration rate and creatinine. While there was a decline in blood pressure after diuresis, this was not clinically significant, given the blood pressure remained in a normal range with improvement in renal function. In conclusion, this study demonstrated that despite concern for preload dependence, significant diuresis in patients with acute decompensated RHF from precapillary PH is not only safe but beneficial.

Genetics of Pulmonary Pressure and Right Ventricle Stress Identify Diabetes as a Causal Risk Factor

Background Epidemiologic studies have identified risk factors associated with pulmonary hypertension and right heart failure, but causative drivers of pulmonary hypertension and right heart adaptation are not well known. We sought to leverage unbiased genetic approaches to determine clinical conditions that share genetic architecture with pulmonary pressure and right ventricular dysfunction. Methods and Results We leveraged Vanderbilt University's deidentified electronic health records and DNA biobank to identify 14 861 subjects of European ancestry who underwent at least 1 echocardiogram with available estimates of pulmonary pressure and right ventricular function. Analyses of the study were performed between 2020 and 2022. The final analytical sample included 14 861 participants (mean [SD] age, 63 [15] years and mean [SD] body mass index, 29 [7] kg/m2). An unbiased phenome-wide association study identified diabetes as the most statistically significant clinical International Classifications of Diseases, Ninth Revision (ICD-9) code associated with polygenic risk for increased pulmonary pressure. We validated this finding further by finding significant associations between genetic risk for diabetes and a related condition, obesity, with pulmonary pressure estimate. We then used 2-sample univariable Mendelian randomization and multivariable Mendelian randomization to show that diabetes, but not obesity, was independently associated with genetic risk for increased pulmonary pressure and decreased right ventricle load stress. Conclusions Our findings show that genetic risk for diabetes is the only significant independent causative driver of genetic risk for increased pulmonary pressure and decreased right ventricle load stress. These findings suggest that therapies targeting genetic risk for diabetes may also potentially be beneficial in treating pulmonary hypertension and right heart dysfunction.

A review of cardio-pulmonary microvascular dysfunction in pulmonary hypertension

Microvascular dysfunction progressing to pulmonary hypertension can be a primary cause of right ventricular failure or a secondary cause because of an underlying systemic illness. Little is known regarding the etiology and epidemiology of coronary microvascular dysfunction in pulmonary hypertension. Despite this limitation, its presence has been described in patients with pulmonary hypertension. This review focuses on the pathogenesis of cardiac and pulmonary microvascular dysfunction in pulmonary hypertension. Additionally, this review provides a contemporary assessment on the diagnosis and treatment of microvascular dysfunction in patients in pulmonary hypertension. This topic is important to raise awareness of microvascular dysfunction in the coronary and pulmonary circulation, so that future studies will investigate its impact on the pulmonary hypertension patient cohort.

VPO1/HOCl/ERK pathway mediates the right ventricular remodeling in rats with hypoxic pulmonary hypertension

Right ventricular (RV) remodeling is a major feature of pulmonary arterial hypertension (PAH). Vascular peroxidase 1 (VPO1) is reported to participate in the process of PAH. This study aims to explore whether VPO1 contributes to hypoxia-induced cardiac hypertrophy and the underlying mechanisms. SD rats were exposure to continuous hypoxia (10% O₂) for 3 weeks, which showed RV hypertrophy (increases in the ratio of RV weight to tibia length, cardiac cell size and hypertrophic markers), concomitant with upregulation of VPO1, elevation in hypochlorous acid (HOCl) production and ERK phosphorylation. In hypoxia (3% O₂)-induced hypertrophic H9c2 cells, similar characteristics of cardiac hypertrophy to that of hypoxia-treated rats were observed. Administration of VPO1 siRNA or NaHS (the HOCl inhibitor) suppressed HOCl production, ERK phosphorylation, and cardiac hypertrophy. Replacement of hypoxia with NaClO (exogenous HOCl) could also induce cardiac cell hypertrophy and activate ERK signaling pathway. In addition, hypoxia-induced cardiac hypertrophy could be blocked by PD98059 (the ERK-specific inhibitor). Based on these observations, we conclude that VPO1 promotes RV remodeling in PAH rats through catalyzing HOCl production, leading to the activation of ERK signaling. Thus, VPO1 may have the potential as a therapeutic target for PAH.

Ventricular mass discriminates pulmonary arterial hypertension as redefined at the Sixth World Symposium on Pulmonary Hypertension

Cardiac magnetic resonance (CMR) measures of right ventricular (RV) mass, volumes, and function have diagnostic and prognostic value in pulmonary arterial hypertension (PAH). We hypothesized that RV mass-based metrics would discriminate incident PAH as redefined by the lower mean pulmonary arterial pressure (mPAP) threshold of >20 mmHg at the Sixth World Symposium on Pulmonary Hypertension (6th WSPH). Eighty-nine subjects with suspected PAH underwent CMR imaging, including 64 subjects with systemic sclerosis (SSc). CMR metrics, including RV and left ventricular (LV) mass, were measured. All subjects underwent right heart catheterization (RHC) for assessment of hemodynamics within 48 h of CMR. Using generalized linear models, associations between CMR metrics and PAH were assessed, the best subset of CMR variables for predicting PAH were identified, and relationships between mass-based metrics, hemodynamics, and other predictive CMR metrics were examined. Fifty-nine subjects met 6th WSPH criteria for PAH. RV mass metrics, including ventricular mass index (VMI), demonstrated the greatest magnitude difference between subjects with versus without PAH. Overall and in SSc, VMI and RV mass measured by CMR were among the most predictive variables discriminating PAH at RHC, with areas under the receiver operating characteristic curve 0.86 and 0.83. respectively. VMI increased linearly with pulmonary vascular resistance and with mPAP in PAH, including in lower ranges of mPAP associated with mild PAH. VMI ≥ 0.37 yielded a positive predictive value of 90% for discriminating PAH. RV mass metrics measured by CMR, including VMI, discriminate incident, treatment-naïve PAH as defined by 6th WSPH criteria.

Critical Care Management of Decompensated Right Heart Failure in Pulmonary Arterial Hypertension Patients - An Ongoing Approach

Despite substantial advancements in diagnosis and specific medical therapy in pulmonary arterial hypertension patients’ management, this condition continues to represent a major cause of mortality worldwide. In pulmonary arterial hypertension, the continuous increase of pulmonary vascular resistance and rapid development of right heart failure determine a poor prognosis. Against targeted therapy, patients inexorable deteriorate over time. Pulmonary arterial hypertension patients with acute right heart failure who need intensive care unit admission present a complexity of the disease pathophysiology. Intensive care management challenges are multifaceted. Awareness of algorithms of right-sided heart failure monitoring in intensive care units, targeted pulmonary hypertension therapies, and recognition of precipitating factors, hemodynamic instability and progressive multisystem organ failure requires a multidisciplinary pulmonary hypertension team. This paper summarizes the management strategies of acute right-sided heart failure in pulmonary arterial hypertension adult cases based on recently available data.

Supra-systemic pulmonary hypertension after complicated percutaneous mitral balloon valvuloplasty: a case report and review of literature

BACKGROUND

The World Symposium of Pulmonary Hypertension in 2018, updated the definition of pulmonary hypertension (PH) as mean pulmonary artery pressures (PAP) > 20 mmHg. Pulmonary venous hypertension secondary to left-heart disease, constitutes the most common cause of PH, and the determination of a co-existent pre-capillary (primary) PH becomes paramount, particularly at the moment of evaluating and managing patients with heart failure. Pulmonary artery pressures above the systemic pressures define supra-systemic PH and generally leads to frank right ventricular failure and high mortality.

CASE PRESENTATION

We present the perioperative management of a patient with rheumatic mitral valve disease, initially found to have severe PH due to pulmonary venous hypertension, who underwent percutaneous mitral balloon valvuloplasty complicated with mitral chordae rupture, severe mitral regurgitation and supra-systemic PH. Multiple medical therapies and an intra-aortic balloon pump were used as means of non-surgical management of this complication.

CONCLUSIONS

This case report illustrates the perioperative implications of combined pre- and post-capillary PH and supra-systemic PH, as this has not been widely discussed in previous literature. A thorough literature review of the clinical characteristics of PH, methods to determine co-existent pre- and post-capillary PH components, as well as concomitant right ventricular failure is presented. Severe PH has known detrimental effects on the hemodynamic status of patients, which can ultimately lead to a decrease in effective cardiac output and poor tissue perfusion.