Inhibition of FGFR Signaling With PD173074 Ameliorates Monocrotaline-induced Pulmonary Arterial Hypertension and Rescues BMPR-II Expression.

BACKGROUND: Numerous studies have demonstrated that fibroblast growth factor-2 (FGF-2) signaling may play a pivotal role in the development of pulmonary arterial hypertension (PAH). Excessive endothelial FGF-2 contributes to smooth muscle hyperplasia and disease progression. PD173074 is a potent FGF receptor 1 (FGFR-1) inhibitor that displays high activity and selectivity. The aim of this study was to investigate the effects of PD173074 on monocrotaline-induced PAH. We also evaluated whether FGFR-1 inhibition could attenuate bone morphogenetic protein type II receptor (BMPR-II) downregulation in the monocrotaline model. METHODS: PAH model was established by a single intraperitoneal injection of monocrotaline. And then a daily intraperitoneal injection of PD173074 (20 mg/kg) was administered from day 14 to day 28. Hemodynamic parameters, right ventricular hypertrophy index and morphometry were evaluated at day 28. Western blot and immunohistochemical analyses were used to determine the expression of FGF-2 and bone morphogenetic protein signaling in the lung tissue. RESULTS: The expression of FGF-2 and FGFR-1 was upregulated in lung tissue after monocrotaline injection and it was accompanied by hemodynamic changes and pulmonary vascular remodeling. PD173074 treatment ameliorated PAH and vascular remodeling. It decreased ERK1/2 activation and rescued total Akt expression, leading to a reduction in both proliferation and apoptosis in the lung. Besides, PD173074 rescued the expression of BMPR-II and p-Smad 1/5/8. CONCLUSION: These results suggest that PD173074 can alleviate monocrotaline-induced pulmonary arterial hypertension and it may be a useful option for PAH. Our data also suggest a role of FGF-2/bone morphogenetic protein signaling interaction in PAH.

Oral targeted therapies in the treatment of pulmonary arterial hypertension: a meta-analysis of clinical trials.

BACKGROUND: Oral targeted therapies have been widely used in the treatment of pulmonary arterial hypertension (PAH). Many new oral agents emerge for PAH in recent years. In this study, we performed a meta-analysis to evaluate the efficacy and safety of oral targeted therapies in PAH, focusing on overall survival improvement. METHODS: Randomized controlled trials of oral targeted therapies in patients with PAH published through September 2013 were identified by searching the Cochrane Library, EMBASE, and PUBMED databases. We calculated risk ratios for dichotomous data and weighted mean differences with 95% confidence intervals for continuous data. RESULTS: 18 trials with a total of 4363 subjects were indentified in the meta-analysis. Analysis by drug class revealed that phosphodiesterase type 5 inhibitors (PDE-5Is) were associated with a statically significant reduction in mortality (RR 0.22; 95% CI 0.07-0.71, p = 0.011), while other drugs only showed a trend toward reducing mortality. Compared with placebo, endothelin receptor antagonists (ERAs), PDE-5Is and riociguat significantly reduced clinical worsening, ameliorated WHO function class, and increased the 6-min walk distance. However, oral prostanoids only showed a mild effect on 6-min walk distance (19.88 m; 95% CI 10.12-29.64, p = 0.000), and did not have any effect on reducing mortality and clinical worsening. Moreover, oral prostanoids significantly increased the incidence of withdrawal due to adverse effects (RR 3.41; 95% CI 2.06-5.63, p = 0.000). CONCLUSIONS: This meta-analysis suggests that all oral agents confer a therapeutic benefit. Of these, only PDE-5Is has a proven survival benefit. ERAs and riociguat are efficient in reducing clinical worsening, and ameliorating exercise capacity. Oral prostanoids have the significant adverse effects and weak therapeutic effects.

Prostanoid therapy for pulmonary arterial hypertension: a meta-analysis of survival outcomes.

BACKGROUND: Prostanoids have played an important role in the treatment of pulmonary arterial hypertension (PAH). However, whether prostanoid therapy provides a survival advantage is still not clear. The aim of this meta-analysis was to evaluate the efficacy and safety of prostanoids in PAH, focusing on the improvement in overall survival. METHODS: Trials were identified from the Cochrane Library, EMBASE, and PUBMED databases. We calculated risk ratios (RR) for dichotomous data and weighted mean differences with 95 % confidence intervals (CI) for continuous data. RESULTS: Fourteen trials with a total of 2,244 adult patients (1,189 patients in the prostanoid treatment group and 1,055 patients in the placebo group) were included in the meta-analysis. All-cause mortality rate in the control group was 4.17 %. In a 13.4-week follow-up, prostanoid treatment was associated with a 44 % reduction in mortality (RR 0.56; 95 % CI 0.35-0.88; P = 0.01).Subgroup analysis suggested that only treatment with intravenous prostanoids provided a survival benefit. Compared with placebo, prostanoids significantly reduced clinical worsening (RR 0.60; 95 % CI 0.46-0.80; P = 0.0003), increased the 6-min walk distance by 27.95 m, reduced mean pulmonary arterial pressure and pulmonary vascular resistance, and increased the cardiac index and mixed venous oxygen saturation. However, patients receiving prostanoid treatment showed a much higher incidence (RR 3.25; 95 % CI 2.07-5.10; P<0.00001) of withdrawal due to its adverse effects. CONCLUSION: The results of this meta-analysis suggest that treatment with prostanoids improves the survival of patients with PAH.

Survival advantages of excess body mass index in patients with idiopathic pulmonary arterial hypertension.

OBJECTIVE: An obesity paradox, a "paradoxical" decrease in morbidity and mortality with increasing body mass index (BMI), has been shown in patients with heart failure. However, the impact of BMI in patients with idiopathic pulmonary arterial hypertension (IPAH) has not been studied. This study aims to find out whether BMI is a prognostic factor in IPAH. METHODS AND RESULTS: We analysed 173 patients with IPAH. The patients were subclassified into categories of BMI defined as: under-weight (< 18.5 kg/m2), normal weight (18.5 to 24.9 kg/m2), overweight and obese (25 to 34.9 kg/m2). The three BMI groups had similar profiles in terms of haemodynamic parameters assessed by right heart catheterization and level of NT-proBNP. The overweight and obese group had higher age, and lower WHO functional class, larger left ventricular end-diastolic dimensions (LVEDDs) than the other two groups.The Kaplan-Meier survival curves for the three BMI categories demonstrated that the overweight and obese group had a significantly higher survival rate than the normal weight and underweight groups (log-rank test, P = 0.027, P = 0.000, respectively). In a stepwise forward regression, lower BMI, higher WHO functional class, lower cardiac index, smaller LVEDDs and absence of targeted medication remained independent predictors of mortality. CONCLUSIONS: Excess body mass is a protective factor for death in patients with IPAH.

High-Burden Premature Atrial Contractions Predict New-Onset Atrial Fibrillation After Surgical Septal Myectomy.

Although increased premature atrial contractions (PACs) reportedly predict atrial fibrillation (AF) in both general and specific (e.g., patients with stroke) populations, early postoperative AF (POAF) risk in patients with increased PAC burden who require cardiac surgery remains unclear. We examined the correlation between different preoperative PAC burdens and POAF in patients with obstructive hypertrophic cardiomyopathy (OHCM) who underwent surgical treatment. We analyzed 304 consecutively admitted patients with OHCM without previous AF who underwent isolated septal myectomy between January 2015 and December 2018. All patients underwent preoperative 24-hour Holter electrocardiogram monitoring. PACs were present in 259 patients (85.20%) and absent in 45 patients (14.80%). According to the cut-off PAC number of 100 beats/24 hours, there were 211 patients (69.41%) with low-burden PACs and 48 patients (15.79%) with high-burden PACs. AF after septal myectomy occurred in 73 patients, which consisted of 3/45 in the non-PAC group (6.67%), 47/211 in the low-PAC-burden group (22.27%), and 23/48 in the high PAC burden group (47.92%). POAF incidence was higher in both low- and high-burden patients than in patients without PAC (p <0.01). Multivariate logistic regression analyses demonstrated that high-burden PACs (p = 0.02) and age (p <0.01) but not low-burden PACs (p = 0.22) independently predicted POAF in patients with OHCM. The area under the receiver operating characteristic curve for preoperative PACs was 0.72 (95% confidence interval 0.66 to 0.79, p <0.01, sensitivity: 68.49%, specificity: 69.26%). In conclusion, POAF incidence was significantly higher in patients with preoperative high-burden PACs and can predict POAF in patients with OHCM.

Clinical Efficacy and Safety of Cox-Maze IV Procedure for Atrial Fibrillation in Patients With Hypertrophic Obstructive Cardiomyopathy.

Objective: Atrial fibrillation is the most prevalent persistent arrhythmia in patients with hypertrophic obstructive cardiomyopathy. Comparative analyses of the safety and effectiveness of septal myectomy with and without surgical ablation are limited. This study aimed to compare the outcomes of septal myectomy with and without the Cox-maze IV procedure in patients with hypertrophic obstructive cardiomyopathy and atrial fibrillation. Methods: Ninety-four patients with hypertrophic obstructive cardiomyopathy and atrial fibrillation who underwent septal myectomy were analyzed, we divided it into concomitant Cox maze surgery (Cox-maze group) and no concomitant Cox maze operation (no Cox-maze group). Freedom from atrial fibrillation recurrence and all-cause mortality after surgery were assessed. Results: Freedom from all-cause mortality after septal myectomy at 1, 3, and 5 years was 98.5 ± 1.5% each in the Cox-maze group and 90.8 ± 6.3%, 85.1 ± 8.1%, and 85.1 ± 8.1%, respectively, in the no Cox-maze group. Patients in the no Cox-maze group had lower survival, freedom from atrial fibrillation recurrence off antiarrhythmic drugs, and arrhythmia control rate (including patients with successful antiarrhythmic drug conversion) than those in the Cox-maze group (P = 0.046, P = 0.040, and P = 0.012, respectively). Patients who underwent the Cox-maze IV procedure had lower atrial fibrillation recurrence rate than those who did not (hazard ratio, 0.141; 95% confidence interval, 0.042-0.479; P = 0.002). Post-operative increases in left atrial diameters (hazard ratio, 1.099; 95% confidence interval, 1.024-1.179; P = 0.009) were associated with atrial fibrillation recurrence. Conclusions: The Cox-maze IV procedure combined with septal myectomy improved mid-term survival and reduced mid-term atrial fibrillation recurrence in patients with hypertrophic obstructive cardiomyopathy and atrial fibrillation. The concomitant Cox-maze IV procedure was associated with a lower atrial fibrillation recurrence in patients with surgical hypertrophic obstructive cardiomyopathy and atrial fibrillation.

Potential biomarkers and targets in reversibility of pulmonary arterial hypertension secondary to congenital heart disease: an explorative study.

Whether pulmonary arterial hypertension (PAH) is reversible in congenital heart disease (CHD) is important for the operability of CHD. However, little is known about that. Our research was aimed at exploring novel biomarkers and targets in the reversibility of CHD-PAH. CHD-PAH patients diagnosed with right heart catheterization (RHC) were enrolled (n = 14). Lung biopsy was performed during the repair surgery. After one year follow-up, mean pulmonary arterial pressures (mPAP) were evaluated by RHC to determine the diagnosis of reversible (mPAP < 25 mmHg, n = 10) and irreversible (mPAP ≥ 25 mmHg, n = 4) PAH. Harvested normal lung tissues (n = 6) were included as the control group. Pulmonary arteriole lesions were identified by pathological grading in tissue staining. iTRAQ-labelled mass-spectrometry analysis followed by immunohistochemistry and western blot was used to explore the most meaningful differential proteins. For enrolled patients, the histopathological grading of pulmonary vascular lesions in reversible CHD-PAH patients was all at grades 0-II while grades III-IV were shown only in irreversible CHD-PAH patients. Proteomic analysis identified 85 upregulated and 75 downregulated proteins, including cytoskeletal proteins and collagen chains, mainly involved in cell adhesion, extracellular matrix, cytoskeleton, immune response, and complement pathways. Among them, caveolin-1, filamin A expression, and cathepsin D combined with macrophagocytes counts were significantly increased; glutathione S-transferase mu1 (GSTM1) expression was significantly decreased in the irreversible CHD-PAH group (all P < 0.05). Caveolin-1, filamin A, and cathepsin D expression showed a positive relation and GSTM1 showed a negative relation with pathological grading. Upregulated caveolin-1, filamin A, and cathepsin D combined with increased macrophagocytes and downregulated GSTM1 may be potential biomarkers and targets in the irreversibility CHD-PAH, and which may be useful in evaluating the operability and understanding the irreversibility of CHD-PAH. Expression of these pathological biomarkers combined with pathological changes in lung biopsy may have great value in predicting the irreversibility of PAH.

High levels of serum lactate dehydrogenase correlate with the severity and mortality of idiopathic pulmonary arterial hypertension.

Liver dysfunction reflects the status of heart failure, and previous studies have demonstrated that serum lactate dehydrogenase (S-LDH) levels are increased in patients exhibiting heart failure and liver dysfunction. Right heart failure is a main characteristic of idiopathic pulmonary arterial hypertension (IPAH). The aim of the present study was to assess the prognostic significance of S-LDH levels in patients with IPAH. S-LDH levels were determined in 173 patients with IPAH, and these patients were subclassified into two groups according to a defined upper reference limit of S-LDH (250 IU/l). Right heart catheterization was performed in all patients. A total of 53 patients were found to have elevated S-LDH to ≥250 IU/l. In a mean follow-up period of 31.2±17.9 months, 57 patients succumbed. In the group with lower S-LDH levels (S-LDH <250 IU/l), 16.7% of the patients succumbed, compared with 69.8% of patients in the group with higher S-LDH levels (S-LDH ≥250 IU/l). The Kaplan-Meier survival curves demonstrated that patients with higher S-LDH levels had a significantly lower survival rate than did those with lower S-LDH levels (log-rank test, P<0.001). Cox proportional hazard analyses identified reduced body mass index, reduced cardiac index, elevated World Health Organization functional class, higher S-LDH and an absence of PAH-targeted therapy as significant predictors of adverse outcomes. In conclusion, elevated S-LDH is a risk factor for mortality in patients with IPAH.