Pulmonary hypertension-specific therapy in patients with chronic respiratory insufficiency

Pulmonary vascular resistance predicts the mortality in patients with bronchiectasis-associated pulmonary hypertension

OBJECTIVE

Pulmonary hypertension is a severe complication of bronchiectasis, characterized by elevated pulmonary vascular resistance (PVR) and subsequent right heart failure. The association between PVR and mortality in bronchiectasis-associated pulmonary hypertension has not been investigated previously.

METHODS

In the present study, a retrospective analysis was conducted on 139 consecutive patients diagnosed with bronchiectasis-associated pulmonary hypertension based on right heart catheterization, enrolled between January 2010 and June 2023. Baseline clinical characteristics and hemodynamic assessment were analyzed. The survival time for each patient was calculated in months from the date of diagnosis until the date of death or, if the patient was still alive, until their last visit.

RESULTS

Patients with bronchiectasis-associated pulmonary hypertension exhibited estimated survival rates of 89.5, 70, and 52.9 at 1-year, 3-year, and 5-year intervals respectively, with a median survival time of 67 months. Multivariable Cox regression analysis revealed that increased age [(adjusted hazard ratio per year 1.042, 95% confidence interval (CI) 1.008-1.076, P = 0.015] and elevated PVR (adjusted HR per 1 Wood Units 1.115, 95% CI 1.015-1.224, P = 0.023) were associated with an increased risk of all-cause mortality. In contrast, higher BMI was associated with a decreased risk of all-cause death (adjusted hazard ratio per 1 kg/m2 0.915, 95% CI 0.856-0.979, P = 0.009). Receiver-operating characteristic analyses identified a cutoff value for PVR at 4 Wood Units as predictive for all-cause death within 3 years [area under the curve (AUC) = 0.624; specificity= 87.5%; sensitivity= 35.8%; P < 0.05]. Patients with a PVR greater than 4 Wood Units had a significantly higher risk of all-cause death compared with those with 4 Wood Units or less (adjusted hazard ratio 2.392; 95% CI 1.316-4.349; P = 0.019). Notably, there were no significant differences in age, sex, BMI, WHO functional class, 6-min walk distance, and NT-proBNP levels at baseline between patients categorized as having 4 Wood Units or less or greater than 4 Wood Units for PVR.

CONCLUSION

Based on these data, PVR could serve as a discriminative marker for distinguishing between nonsevere pulmonary hypertension (PVR ≤ 4 Wood Units) and severe pulmonary hypertension (PVR > 4 Wood Units). The utilization of a PVR cutoff value of 4.0 Wood Units provides enhanced prognostic capabilities for predicting mortality.

Preventive treatment with ginsenoside Rb1 ameliorates monocrotaline-induced pulmonary arterial hypertension in rats and involves store-operated calcium entry inhibition

CONTEXT

Ginsenoside Rb1, the main active ingredient of ginseng, exhibits ex vivo depression of store-operated calcium entry (SOCE) and related vasoconstriction in pulmonary arteries derived from pulmonary hypertension (PH) rats. However, the in vivo effects of ginsenoside Rb1 on PH remain unclear.

OBJECTIVE

This study explored the possibility of using ginsenoside Rb1 as an in vivo preventive medication for type I PH, i.e., pulmonary arterial hypertension (PAH), and potential mechanisms involving SOCE.

MATERIALS AND METHODS

Male Sprague-Dawley rats (170-180 g) were randomly divided into Control, MCT, and MCT + Rb1 groups (n = 20). Control rats received only saline injection. Rats in the MCT + Rb1 and MCT groups were intraperitoneally administered single doses of 50 mg/kg monocrotaline (MCT) combined with 30 mg/kg/day ginsenoside Rb1 or equivalent volumes of saline for 21 consecutive days. Subsequently, comprehensive parameters related to SOCE, vascular tone, histological changes and hemodynamics were measured.

RESULTS

Ginsenoside Rb1 reduced MCT-induced STIM1, TRPC1, and TRPC4 expression by 35.00, 31.96, and 32.24%, respectively, at the protein level. SOCE-related calcium entry and pulmonary artery contraction decreased by 162.6 nM and 71.72%. The mean pulmonary artery pressure, right ventricle systolic pressure, and right ventricular mass index decreased by 19.5 mmHg, 21.6 mmHg, and 39.50%. The wall thickness/radius ratios decreased by 14.67 and 17.65%, and the lumen area/total area ratios increased by 18.55 and 15.60% in intrapulmonary vessels with 51-100 and 101-150 μm o.d.

CONCLUSION

Ginsenoside Rb1, a promising candidate for PH prevention, inhibited SOCE and related pulmonary vasoconstriction, and relieved MCT-induced PAH in rats.

Long-term outcome with focus on pulmonary hypertension in Obesity Hypoventilation Syndrome

INTRODUCTION

Pulmonary Hypertension (PH) is a frequent comorbidity in Obesity Hypoventilation Syndrome (OHS).

OBJECTIVE

We investigated long-term outcome of OHS with a particular emphasis on PH.

METHODS

In a prospective design, 64 patients with OHS and established noninvasive positive pressure ventilation (NPPV), were assessed by serum biomarkers, right heart catheterization, blood gases analysis, lung function, Epworth-Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), World Health Organization-functional class (WHO-FC) and health-related quality of life (HRQL) via the Severe Respiratory Insufficiency (SRI) questionnaire. After a planned follow-up of 5 years patients were reassessed regarding vital status, WHO-FC, ESS, SRI, PSQI, body mass index (BMI) and NPPV use. Prognostic markers were explored using univariate and multivariate Cox regression analyses.

RESULTS

At the 5-year follow-up, BMI tended to decrease (P = 0.05), while WHO-FC, ESS and PSQI remained unchanged. HRQL deteriorated in terms of SRI summary score and most subdomains (P < .05 each). NPPV adherence still was high (89%), while daily NPPV use increased from 6.7 (5.1; 8.0) h/d to 8.2 (7.4; 9.0) h/d (P < .05). After a 5-year follow-up, mortality was 25.8%. In univariate regression analyses only age > 69.5 years (HR = 4.145, 95%-CI = 1.180-14.565, P = 0.016), NT-proBNP > 1256 pg/mL (HR = 5.162, 95%-CI = 1.136-23.467, P = 0.018), diffusion capacity for carbon monoxide (DLCO, %pred) (HR = 0.341, 95%-CI = 0.114-1.019, P = 0.043) and higher oxygen use during daytime (HR = 5.236, 95%-CI = 1.489-18.406, P = 0.004) predicted mortality. No independent factor predicting mortality was detected in multivariate analysis.

CONCLUSION

Despite a high long-term NPPV use HRQL worsened. Age, oxygen use at baseline, DLCO (%pred) and NT-proBNP, as a surrogate parameter for PH, were related to long-term survival.

[Pulmonary hypertension in chronic respiratory diseases]

Pulmonary hypertension is frequent in advanced chronic respiratory diseases, with an estimated prevalence at the time of pulmonary transplantation of 30-50 % in idiopathic pulmonary fibrosis, 30-50 % in chronic obstructive pulmonary disease, 50 % in combined pulmonary fibrosis and emphysema, 75 % in sarcoidosis, and more than 75 % of cases in pulmonary Langerhans cell histiocytosis. Histologic features include varying degrees of pulmonary arterial remodeling (prominent), vascular rarefaction (emphysema), fibrosis or specific involvement of the pulmonary arteries (idiopathic pulmonary fibrosis, sarcoidosis, lymphangioleiomyomatosis, pulmonary Langerhans cell histiocytosis), in situ thrombosis, and frequently associated involvement of the pulmonary veins (idiopathic pulmonary fibrosis, sarcoidosis). Pulmonary hypertension is usually detected using echocardiography with Doppler, however right heart catheterisation is required to confirm precapillary pulmonary hypertension defined by pulmonary artery pressure ≥ 25 mm Hg, with pulmonary artery wedge pressure ≤ 15 mm Hg. When present, it is associated with decreased exercise capacity and worse mortality. Pulmonary hypertension in chronic respiratory disease is almost invariably multifactorial; hypoxia is one of its main determinants, however supplemental oxygen therapy rarely reverses pulmonary hypertension. Management of pulmonary hypertension in chronic respiratory disease is mostly based on the optimal treatment of the underlying disease. Available data do not support the use of drug therapies specific for pulmonary hypertension in the setting of chronic respiratory diseases, however very few clinical studies have been conducted so far specifically in this context.