Xin-Hai Ni

Comparison of 18F-FDG uptake by right ventricular myocardium in idiopathic pulmonary arterial hypertension and pulmonary arterial hypertension associated with congenital heart disease.

This study measured glucose uptake in the right ventricle (RV) of patients with pulmonary hypertension and investigated the relationship to hemodynamics and survival. Myocardial 18F-fluorodeoxy-glucose (FDG) uptake was measured using single-photon positron emission tomography (SPECT) in 24 patients with idiopathic pulmonary arterial hypertension (IPAH) and 43 patients with congenital heart disease (CHD). In both IPAH and CHD-PAH, RV FDG uptake (RV/LV ratio) was associated with pulmonary vascular resistance (PVR). A second SPECT scan was performed in nine patients after 6 months treatment with sildenafil. PVR decreased from 1683±426 to 1207±383 dyn s−1 cm−5 (P < 0.05) and cardiac index improved from 2.2±0.2 to 2.8±0.5 L/min/m2 (P < 0.01). RV/LV FDG uptake decreased from 1.28±0.32 before treatment to 0.99±0.23 (P < 0.05). Survival in the IPAH group with a baseline RV/LV FDG uptake greater than the median value of 1.20 was significantly lower than that of the group with RV/LV FDG uptake below 1.20 (log-rank test, P < 0.05). In contrast, baseline RV/LV FDG was of little informative value in CHD. FDG uptake by the RV reflects the severity of PVR in PAH. Increased RV FDG uptake is a marker of poor prognosis in IPAH and is reduced in patients receiving effective therapy. It could prove useful in the early clinical assessment of novel therapies for PAH.

Echocardiographic parameters in patients with pulmonary arterial hypertension: correlations with right ventricular ejection fraction derived from cardiac magnetic resonance and hemodynamics.

Background Echocardiography is the most convenient method used to evaluate right ventricular function, and several echocardiographic parameters were studied in previous studies. But the value of these parameters to assess the right ventricular function in patients with pulmonary arterial hypertension (PAH) has not been well defined. Methods Patients with PAH were observed prospectively. Right heart catheterization, echocardiography and cardiac magnetic resonance (CMR) were performed within 1 week interval. The correlations between echocardiographic parameters and right ventricular ejection fraction (RVEF) derived from CMR as well as hemodynamics were analyzed. Results Thirty patients were enrolled including 24 with idiopathic PAH, 5 with PAH associated with connective tissue diseases and 1 with hereditary PAH. All echocardiographic parameters except right ventricular myocardial performance index (RVMPI) correlated significantly with RVEF (tricuspid annual plane systolic excursion [TAPSE], r = 0.440, P = 0.015; tricuspid annular systolic excursion velocity [S’], r = 0.444, P = 0.016; isovolumic acceleration [IVA], r = 0.600, P = 0.001; right ventricular fraction area change [RVFAC], r = 0.416, P = 0.022; ratio of right ventricular transverse diameter to left ventricular transverse diameter [RVETD/LVETD], r = −0.649, P<0.001; RVMPI, r = −0.027, P = 0.888). After adjusted for mean right atrial pressure, mean pulmonary arterial pressure and pulmonary vascular resistance (PVR), only IVA and RVETD/LVETD could independently predict RVEF. Four echocardiographic parameters displayed significant correlations with PVR (TAPSE, r = −0.615, P<0.001; S’, r = −0.557, P = 0.002; RVFAC, r = −0.454, P = 0.012; RVETD/LVETD, r = 0.543, P = 0.002). Conclusions The echocardiographic parameters IVA and RVETD/LVETD can reflect RVEF independently regardless of hemodynamics in patients with PAH. In addition, TAPSE, S’, RVFAC and RVETD/LVETD can also reflect PVR in PAH patients.

Potential diagnostic biomarkers in serum of idiopathic pulmonary arterial hypertension

BACKGROUND The pathogenesis of idiopathic pulmonary arterial hypertension (IPAH) is unknown, and the syndrome of IPAH remains a diagnostic and therapeutic challenge. The present study investigated the disease-specific proteins that aid in the diagnosis of IPAH and thus to study their role in the disease process. METHODS A comparative proteomic analysis was used for clinical screening of serum proteins in 10 patients with IPAH and compared with 10 normal subjects. Furthermore, enzyme linked immunosorbent assay (ELISA) was performed for comparison with serum proteins between individual IPAH patients and controls. RESULTS Nine proteins and their isoforms, including leucine-rich alpha-2-glycoprotein (LRG), haptoglobin precursor, albumin isoform 2, transferrin variant, C3 complement, hydroxypyruvate reductase isoform 1, RAF1, fibrinogen isoformgamma-A and fibrinogen isoformgamma-B showed significant changes in serum of IPAH patients compared with controls by proteomic analysis. And significant higher serum levels of LRG in IPAH patients compared with controls were found by ELISA. Correlation analysis disclosed a significant association between serum LRG concentrations and New York Heart Association (NYHA) functional class (r=0.71, P<0.01) and cardiac output (CO) (r=-0.65, P<0.01). CONCLUSIONS These results indicate that there are significant differences in the expression of proteins in the serum of patients with IPAH and normal subjects. And the measurement of LRG, RAF1 and C3 complement levels in the serum may be helpful for the diagnosis of IPAH. In particular, LRG may be a specific prognostical biomarker of IPAH.

Plasma Soluble ST2 Levels Correlate With Disease Severity and Predict Clinical Worsening in Patients With Pulmonary Arterial Hypertension

Soluble suppression of tumorigenicity (sST2) has been proposed to be a marker for biomechanical strain and a possible predictor of mortality in patients with chronic heart failure. The use of sST2 in pulmonary arterial hypertension (PAH) has not been well defined.

The efficacy and safety of sildenafil in patients with pulmonary arterial hypertension associated with the different types of congenital heart disease.

The difference in underlying pathophysiology in different congenital heart disease (CHD) may have an influence on clinical outcome. It remains unclear whether the effect of sildenafil on pulmonary arterial hypertension (PAH) varies in different types of CHD.

Impact of Sildenafil Therapy on Pulmonary Arterial Hypertension in Adults with Congenital Heart Disease

BACKGROUND It has been demonstrated that sildenafil is effective in patients with pulmonary arterial hypertension (PAH). However, the impact of sildenafil on PAH in adults with congenital heart disease (CHD) has been less investigated. OBJECTIVE In this prospective, open-label, uncontrolled and multicenter study, 60 patients with PAH related to CHD received oral sildenafil (75 mg/day) for 12 weeks. The enrolled patients underwent six-minute walk test (SMWT) and cardiac catheterization at the beginning and the end of the 12 weeks. The primary end point was the changes in exercise capacity assessed by SMWT; the secondary end point included assessment of functional class, evaluation of cardiopulmonary hemodynamics, and clinical worsening (defined as death, transplantation, and rehospitalization for PAH). Drug safety and tolerability were also examined. RESULTS Oral sidenafil significantly increased SMWT distances (422.94 ± 76.95 m vs. 371.99 ± 78.73 m, P < 0.0001). There was also remarkable improvement in Borg dyspnea score (2.1 ± 1.32 vs. 2.57 ± 1.42, P = 0.0307). Moreover, significant improvements in World Healthy Organization (WHO) functional class and cardiopulmonary hemodynamics were also discovered (mean pulmonary artery pressure, P = 0.0002; cardiac index, P < 0.0001; pulmonary vascular resistance, P < 0.0001). Side effects in this study were mild and consistent with reported studies. None of the enrolled patients experienced significant clinical worsening. CONCLUSIONS This study confirmed and extended previous studies. It suggested that oral sildenafil was safe and effective for the treatment of adult patients with CHD-related PAH.

Impact of sildenafil on survival of patients with Eisenmenger syndrome.

The favorable effects of short‐term use of sildenafil on patients with Eisenmenger syndrome have been reported. We further studied the impact of long‐term use of sildenafil on survival of these patients. In this study, the baseline data of patients newly diagnosed as Eisenmenger syndrome in our hospital between January 2005 and December 2009 were retrospectively collected. Patients were followed‐up either by telephone contacts or during visits in our out‐patient clinic. A total of 121 patients (68 patients in conventional group and 53 patients in sildenafil group) were finally included and 29 patients were re‐evaluated after sildenafil therapy for 3–4 months. Compared with the baseline, a 6‐minute walk distance, functional classes, plasma hemoglobin level, and hemodynamics were significantly improved after sildenafil treatment. During a median follow‐up period of 35.8 months, 15 patients died (11 patients in conventional group). The 1‐ and 3‐year survival rates in sildenafil group were 97.0% and 95.2%, significantly higher than 90.6% and 82.9% in conventional group P = .025). Multivariate analysis showed that sildenafil therapy, functional class and mean pulmonary arterial pressure were independently associated with survival. Therefore, long‐term sildenafil therapy improved survival in patients with Eisenmenger syndrome.

Increased levels of plasma CXC-Chemokine Ligand 10, 12 and 16 are associated with right ventricular function in patients with idiopathic pulmonary arterial hypertension.

OBJECTIVE To investigate plasma levels of CXC-Chemokine Ligand 10 (CXCL10), CXC-Chemokine Ligand 12 (CXCL12) and CXC-Chemokine Ligand 16 (CXCL16) in patients with idiopathic pulmonary arterial hypertension (IPAH). METHODS Plasma levels of biomarkers were measured by enzyme-linked immunosorbent assay in 61 patients with IPAH and 20 healthy volunteers. RESULTS Plasma CXCL10, CXCL12 and CXCL16 concentrations were increased significantly in IPAH patients compared with controls, and significantly correlated with N-terminal pro-brain natriuretic peptide, tricuspid annulus plane systolic excursion and right ventricular ejection fraction. CONCLUSIONS Increased levels of CXCL10, CXCL12 and CXCL16 are associated with right ventricular dysfunction in patients with IPAH.

Platelet Distribution Width and Mean Platelet Volume in Idiopathic Pulmonary Arterial Hypertension

BACKGROUND Previous studies have demonstrated that platelet activation occurs in patients with pulmonary arterial hypertension (PAH). Mean platelet volume (MPV) and platelet distribution width (PDW) are two markers of platelet activation, and have recently been recognised as risk predictors of cardiovascular diseases. This study aimed to investigate whether MPV and PDW would be useful to reflect disease severity and predict prognosis in idiopathic PAH (IPAH). METHODS MPV and PDW levels were measured in 82 IPAH patients without antiplatelet or anticoagulant treatment on admission and 82 healthy controls. Concurrent collected data included clinical, haemodynamic and biochemical variables. All patients were followed-up from the date of blood testing. The endpoint was all-cause mortality. RESULTS MPV and PDW were significantly higher in patients with IPAH than in age and sex-matched control subjects (11.4±0.9fl vs. 10.3±0.9fL and 14.3±2.9% vs. 11.9±1.9%, respectively; p=0.000). Pearsons correlation analysis revealed that MPV and PDW correlated positively with right ventricular systolic pressure, mean pulmonary arterial pressure and pulmonary vascular resistance. After a mean follow-up of 14±8 months, 12 patients died of right heart failure. Receiver operating characteristic analysis showed that MPV and PDW could not predict all-cause mortality. Multivariate Cox regression analysis suggested that right/left ventricular end-diastolic diameter ratio and NT-proBNP were independent predictive parameters of all-cause mortality. CONCLUSIONS Our results suggest that MPV and PDW were elevated in patients with IPAH. They could partly reflect disease severity, but did not predict prognosis.

Oral Sildenafil Therapy for Chinese Patients With Pulmonary Arterial Hypertension: A Multicenter Study

The impact of sildenafil on pulmonary arterial hypertension (PAH) in Chinese patients has been less investigated. A prospective, open‐label, uncontrolled and multicenter study, therefore, was carried out to address this issue. Ninety patients with multicause‐induced PAH received oral sildenafil (75 mg/day) for 12 weeks. The 6‐minute walk test (SMWT) and cardiac catheterization were performed at the beginning and the end of the 12 weeks. The primary endpoint was the changes in exercise capacity assessed by the SMWT; the secondary endpoint included assessment of functional class, evaluation of cardiopulmonary hemodynamics, and clinical worsening. Drug safety and tolerability were also examined. The results showed that there was a significant improvement in SMWT distances (342 ± 93 m vs 403 ± 88 m, P < .0001), Borg dyspnea score (2.9 ± 2.6 vs 2.4 ± 2.0, P = .0046), World Health Organization functional class, and cardiopulmonary hemodynamics (mean pulmonary artery pressure, P < .0001; cardiac index, P < .0001; pulmonary vascular resistance, P < .0001) after 12 weeks of oral sidenafil therapy. Almost all enrolled patients did not experience significant clinical worsening. This study confirms and extends the findings of previous studies relating to effects of sildenafil on PAH, suggesting that oral sildenafil is safe and effective for the treatment of adult patients with PAH in the Chinese population.