A sham-controlled randomised trial of pulmonary artery denervation for Group 1 pulmonary arterial hypertension: one-year outcomes of the PADN-CFDA trial.

BACKGROUND: Long-term clinical outcomes after pulmonary artery denervation (PADN) in patients with Group 1 pulmonary arterial hypertension (PAH) have not been reported. AIMS: We aimed to investigate the effect of PADN on 1-year outcomes in patients with PAH. METHODS: In the multicentre PADN-CFDA trial, 128 patients with Group 1 PAH were randomly assigned to PADN plus a phosphodiesterase-5 inhibitor (PDE-5i) versus a sham PADN procedure plus a PDE-5i. The principal endpoint of interest for the present study was clinical worsening at 1 year after randomisation, the composite of worsening of PAH (increase in WHO functional class, need for additional PAH treatments or PAH-related hospitalisation), atrial septostomy, listing for lung transplantation, or all-cause death. RESULTS: One-year clinical follow-up was available in all patients. At 1 year, clinical worsening had occurred in 3 (4.8%) patients in the PADN plus PDE-5i group and in 15 patients (23.1%) in the sham plus PDE-5i group (adjusted hazard ratio: 0.17; 95% confidence interval [CI]: 0.05-0.60; p=0.006), driven by significantly increased rates of PAH-related hospitalisations, worsening functional class and the requirement for additional PAH treatments in the sham group. Results were consistent in high-risk, intermediate-risk and low-risk patients (pinteraction=0.186). Patients treated with PADN plus PDE-5i had an improvement in the between-group change in the six-minute walking distance (6MWD) from baseline to 1 year of 81.2 m (95% CI: 50.3-112.2; p<0.001) compared with PDE-5i treatment alone. CONCLUSIONS: In this multicentre sham-controlled randomised trial, PADN treatment for Group 1 PAH significantly reduced clinical worsening and improved the 6MWD during 1-year follow-up in patients treated with a PDE-5i.

3-Year Outcome in Patients With Combined Precapillary and Postcapillary Pulmonary Hypertension: Results From PADN-5 Trial.

BACKGROUND: Long-term benefits of pulmonary artery denervation (PADN) for patients with combined precapillary and postcapillary pulmonary hypertension (CpcPH) secondary to left heart failure are unknown. OBJECTIVES: The authors sought to report the 3-year clinical results of PADN for patients with CpcPH. METHODS: A total of 98 patients with CpcPH, defined as having mean pulmonary arterial pressure of ≥25 mm Hg, pulmonary capillary wedge pressure of >15 mm Hg, and pulmonary vascular resistance of >3.0 WU, were randomly assigned to receive the sham + sildenafil or PADN. The primary endpoint was the occurrence of clinical worsening defined as cardiopulmonary death, rehospitalization or heart/lung transplantation at 3-year follow-up. Changes in the 6-minute walk distance and N-terminal pro-B-type natriuretic peptide served as secondary points. RESULTS: At the 3-year follow-up, clinical worsening was reported in 49 (50.0%) patients, with 31 (62.0%) in the sham + sildenafil group and 18 (37.5%) in the PADN group (HR: 2.13 [95% CI: 1.19-3.81]; P = 0.011), largely driven by a higher rate of rehospitalization in the sham + sildenafil group (56.2% vs 35.4%; HR: 1.96 [95% CI: 1.07-3.58]; P = 0.029) by Cox proportional hazards regression. At the end of the study, cardiopulmonary-related deaths occurred in 16 (32.0%) patients in the sham and 9 (18.8%) (P = 0.167) patients in the PADN group. PADN also resulted in a more profound increase in the 6-minute walk distance and reduction in N-terminal pro-B-type natriuretic peptide. CONCLUSIONS: PADN is associated with significant improvements in exercise capacity, cardiac function, and clinical outcomes. Further study without approved drugs for pulmonary arterial hypertension is required to confirm the benefits of PADN for patients with CpcPH. (Pulmonary Arterial Denervation in Patients With Pulmonary Hypertension Associated With the Left Heart Failure [PADN-5]; NCT02220335).

Establishment of a canine model of pulmonary arterial hypertension induced by dehydromonocrotaline and ultrasonographic study of right ventricular remodeling.

OBJECTIVE: Pulmonary arterial hypertension (PAH) means high blood pressure in the lungs. We aimed to observe the right ventricular size, wall thickness and characteristic functional changes and their associations with PAH in an established model of beagle dogs, and to explore convenient, reliable and sensitive ultrasound indicators for assessing right ventricular remodeling. METHODS: Twenty healthy beagle dogs (8-10 kg) were randomly divided into control group (N-dimethylformamide, n = 10) and dehydromonocrotaline (DHMCT) group (DHMCT, n = 10). N-dimethylformamide or DHMCT was injected through a catheter into the right atrium, and then right heart catheterization, routine echocardiography and two-dimensional speckle tracking imaging (2D-STI) were performed before modeling (0 weeks) and 8, 14 weeks after modeling. Hemodynamic parameters and right ventricular function-related ultrasound data were acquired. At the end of the experiment, the animals were killed and the lung tissues were taken for HE staining. Left and right ventricular walls were separated and weighed respectively, and right ventricular hypertrophy index (RVHI) was measured. The associations of the routine ultrasound data and 2D-STI data at each time point with hemodynamic parameters and RVHI were analyzed. RESULTS: At 0, 8 and 14 weeks, gradual decreases in the right ventricular global longitudinal strain (RVLS) were found in DHMCT group. RVH occurred in DHMCT group, and DHMCT group had a significantly higher RVHI than that of control group (49.83 ± 4.83% vs. 39.80 ± 1.40%, P < .001) and larger pulmonary artery media thickness. RVLS had significant positive correlations with RVSP (r = 0.74, P < .001), mRVP (r = 0.72, P < .001), PASP (r = 0.75, P < .001), mPAP (r = 0.72, P < .001) and PVR (r = 0.68, P < .001). There was a significant positive correlation between RVLS and RVHI (r = 0.74, P < .001). CONCLUSION: The right ventricular function in PAH can be effectively assessed by echocardiography, and RVLS measured by 2D-STI sensitively reflects right ventricular remodeling following PAH.

Treatment effects of pulmonary artery denervation for pulmonary arterial hypertension stratified by REVEAL risk score: Results from PADN-CFDA trial.

BACKGROUND: The differential treatment effect of pulmonary artery denervation (PADN) in pulmonary arterial hypertension (PAH) patients with different risk burdens remains unclear. This study aimed to determine the effectiveness of PADN in low vs intermediate-high-risk PAH patients. METHODS: In total, 128 patients with treatment naive PAH included in the PADN-CFDA trial were categorized into low-risk and intermediate-high-risk patients. The primary endpoint was the between-group difference in the change in 6-min walk distance (6 MWD) from baseline to 6 months. RESULTS: In the intermediate-high-risk group, those treated with PADN and PDE-5i had a greater improvement in 6 MWD from baseline to 6 months as compared to those treated with sham plus PDE-5i. From baseline to 6 months, pulmonary vascular resistance (PVR) was reduced by -6.1 ± 0.6 and -2.0 ± 0.7 Wood units following PADN plus PDE-5i and sham plus PDE-5i, respectively, along with the significant reduction of NT-proBNP in the intermediate-high-risk group. However, there were no significant differences in 6 MWD, PVR, and NT-proBNP between the PADN plus PDE-5i and sham plus PDE-5i groups among low-risk patients. Moreover, the right ventricular function was equally improved by PADN treatment across the low-, intermediate-, and high-risk groups. Clinical worsening was less with PADN plus PDE-5i treatment during the 6-month follow-up. CONCLUSIONS: In patients with pulmonary arterial hypertension, pulmonary artery denervation plus PDE-5i improved exercise capacity, NT-proBNP, hemodynamic, and clinical outcomes during the 6-month follow-up among intermediate-high risk patients.

Comparison of different quantitative evaluation protocols for peri-device leak detection using cardiac computed tomography angiography after left atrial appendage closure.

This study seeks to propose and compare different quantitative evaluation methods for identifying patients with peri-device leak (PDL) using cardiac computed tomography angiography (CCTA). Patients who had undergone left atrial appendage (LAA) closure and both transesophageal echocardiography (TEE) and CCTA were enrolled. Hounsfield units (HU) were measured in the proximal and distal regions of the left atrial appendage (p-LAA, d-LAA) on the CCTA, and the average of the two was determined (a-LAA). The relative HU ratios of the LAA to the center of the left atrium (LA) were calculated (p-LAA/c-LA, d-LAA/c-LA, a-LAA/c-LA). The area under the curve (AUC) for the LAA HU and the LAA/LA HU ratio were analyzed and compared. Fifty-one patients were included in this study. Pairwise comparisons showed a statistically significant difference (p = 0.029) in diagnostic performance between the d-LAA (AUC = 0.868) and a-LAA (AUC = 0.972). There were no significant differences between the a-LAA and p-LAA (p = 0.549) or between the d-LAA and p-LAA (p = 0.053). At the optimal cutoff for a-LAA of 115.5 HU, the sensitivity was 100%, the specificity was 88%. At the optimal cutoff for p-LAA of 109 HU, the sensitivity was 100%, the specificity was 84%. The LAA/LA HU ratio did not exhibit better diagnostic performance than HU attenuation in the LAA (p > 0.05). The a-LAA > 115.5 is useful in identifying PDL. Due to its convenience and intuitiveness, p-LAA > 109.0 can also be used as an alternative protocol for a-LAA.

Pulmonary Artery Denervation for Pulmonary Arterial Hypertension: A Sham-Controlled Randomized PADN-CFDA Trial.

BACKGROUND: World Health Organization (WHO) group 1 pulmonary arterial hypertension (PAH) is a progressive, debilitating disease. Previous observational studies have demonstrated that pulmonary artery denervation (PADN) reduces pulmonary artery pressures in PAH. However, the safety and effectiveness of PADN have not been established in a randomized trial. OBJECTIVES: The aim of this study was to determine the treatment effects of PADN in patients with group 1 PAH. METHODS: Patients with WHO group 1 PAH not taking PAH-specific drugs for at least 30 days were enrolled in a multicenter, sham-controlled, single-blind, randomized trial. Patients were assigned to receive PADN plus a phosphodiesterase-5 inhibitor or a sham procedure plus a phosphodiesterase-5 inhibitor. The primary endpoint was the between-group difference in the change in 6-minute walk distance from baseline to 6 months. RESULTS: Among 128 randomized patients, those treated with PADN compared with sham had a greater improvement in 6-minute walk distance from baseline to 6 months (mean adjusted between-group difference 33.8 m; 95% CI: 16.7-50.9 m; P < 0.001). From baseline to 6 months, pulmonary vascular resistance was reduced by -3.0 ± 0.3 WU after PADN and -1.9 ± 0.3 WU after sham (adjusted difference -1.4; 95% CI: -2.6 to -0.2). PADN also improved right ventricular function, reduced tricuspid regurgitation, and decreased N-terminal pro-brain natriuretic peptide. Clinical worsening was less (1.6% vs 13.8%; OR: 0.11; 95% CI: 0.01-0.87), and a satisfactory clinical response was greater (57.1% vs 32.3%; OR: 2.79; 95% CI: 1.37-5.82) with PADN treatment during 6-month follow-up. CONCLUSIONS: In patients with WHO group 1 PAH, PADN improved exercise capacity, hemodynamic status, and clinical outcomes during 6-month follow-up. (Safety and Efficacy of Pulmonary Artery Denervation in Patients With Pulmonary Arterial Hypertension [PADN-CFDA]; NCT03282266).

Long-term mortality after pulmonary artery denervation stratified by baseline functional class in patients with pulmonary arterial hypertension: Long-term mortality after PADN stratified by functional class.

Aims: This study aimed to assess the long-term effects of pulmonary artery denervation (PADN) on mortality in patients with pulmonary arterial hypertension (PAH). Methods and results: Between March 2012 and March 2018, a total of 120 patients with PAH, who underwent PADN treatment and were prospectively followed up, were analysed. Patients were classified into World Health Organization (WHO) Functional Class I and II (FC 1-2; n=46) and Functional Class III and IV (FC 3-4; n=74) according to their FC prior to PADN. The primary endpoint was lung transplantation-free mortality until March 2021. The secondary endpoint was a change in the six-minute walk distance (6MWD). During the median of 4.8 years of follow-up, 23 (19.2%) patients died, predominantly from the FC 3-4 group (25.7%), compared to 8.7% in the FC 1-2 group (p=0.034). The mortality rate at one year (2.2% vs 12.2%, p=0.087) and three years (6.5% vs 17.6%, p=0.102) was numerically low in the FC 1-2 group versus the FC 3-4 group, respectively. The median net increase of 6MWD was +29 m in the FC 1-2 group, compared to +60.5 m in the FC 3-4 group (p=0.037). Conclusions: PADN results in significant improvements in survival at long-term follow-up, especially in patients with PAH in FC 3-4. This study was the continuation of the PADN-1 study which was registered at URL: http://www.chictr.trc.com.cn. Unique identifier: chiCTR-ONC-12002085.

Pulmonary Artery Denervation Significantly Increases 6-Min Walk Distance for Patients With Combined Pre- and Post-Capillary Pulmonary Hypertension Associated With Left Heart Failure: The PADN-5 Study.

OBJECTIVES: The authors sought to assess the benefits of pulmonary artery denervation (PADN) among combined pre- and post-capillary pulmonary hypertension (CpcPH) patients in a prospective, randomized, sham-controlled trial. BACKGROUND: PADN has been shown to improve hemodynamics of pulmonary arterial hypertension in a series of patients. Additionally, benefits of targeted medical therapy for patients with CpcPH secondary to left-sided heart failure are unknown. METHODS: Ninety-eight CpcPH patients, defined as mean pulmonary arterial pressure ≥25 mm Hg, pulmonary capillary wedge pressure >15 mm Hg, and pulmonary vascular resistance (PVR) >3.0 Wood units (WU), were randomly assigned to PADN or sildenafil plus sham PADN. Standard medical therapy for heart failure was administered to all patients in both groups. The primary endpoint was the increase in the 6-min walk distance at the 6-month follow-up. The secondary endpoint was change in PVR. Clinical worsening was assessed in a post hoc analysis. The main safety endpoint was occurrence of pulmonary embolism. RESULTS: At 6 months, the mean increases in the 6-min walk distance were 83 m in the PADN group and 15 m in the sildenafil group (least square mean difference 66 m, 95% confidence interval: 38.2 to 98.8 m; p < 0.001). PADN treatment was associated with a significantly lower PVR than in the sildenafil group (4.2 ± 1.5 WU vs. 6.1 ± 2.9 WU; p = 0.001). Clinical worsening was less frequent in the PADN group compared with the sildenafil group (16.7% vs. 40%; p = 0.014). At the end of the study, there were 7 all-cause deaths and 2 cases of pulmonary embolism. CONCLUSIONS: PADN is associated with significant improvements in hemodynamic and clinical outcomes in patients with CpcPH. Further studies are warranted to define its precise role in the treatment of this patient population. (Pulmonary Arterial Denervation in Patients With Pulmonary Hypertension Associated With the Left Heart Failure [PADN-5]; NCT02220335).

Pulmonary artery denervation improves hemodynamics and cardiac function in pulmonary hypertension secondary to heart failure.

This study aimed to determine the benefits and correlated mechanisms of pulmonary artery denervation (PADN) for heart failure (HF) pulmonary hypertension (PH). PH secondary to HF is associated with poor clinical outcomes because there is no proper therapy for it. PADN showed improved outcomes for patients with HF-PH. However, the underlying mechanisms remain unknown. Supracoronary aortic banding (SAB) was used to create HF-PH models. Sprague-Dawley rats were randomly assigned to control, SAB, sham, SAB with PADN, and SAB without PADN groups. Surgical (longitudinally damaging vessel nerves) and chemical (10% phenol applied to the surface of nerves) PADN was performed for animals in the SAB with PADN group. Morphological, echocardiographic, hemodynamic, and protein expression changes were measured four weeks thereafter. Adrenergic receptor (AR) expressions of pulmonary arteries from four HF-PH patients and four patients without PH were measured. Ten HF-PH patients who underwent PADN were followed-up for six months. SAB-induced HF-PH was achieved by 50% of animals. Surgical and chemical PADN was associated with significant improvements in pulmonary artery muscularization, hemodynamics, and right ventricular functions. In pulmonary arterial specimens from HF-PH patients, ß2-AR and α1A/B-AR, as well as eNOS, were downregulated and α1D-AR was upregulated compared to those from patients without PH. PADN led to a mean increase of 84 m during the 6-min walk distance for HF-PH patients at six-month follow-up. HF-PH was characterized by downregulated ß2-AR, α1A-AR, and α1B-AR and by upregulated α1D-AR. PADN is associated with significant improvements in hemodynamics and pulmonary artery remodeling.

Low shear stress induces vascular eNOS uncoupling via autophagy-mediated eNOS phosphorylation.

Uncoupled endothelial nitric oxide synthase (eNOS) produces O2- instead of nitric oxide (NO). Earlier, we reported rapamycin, an autophagy inducer and inhibitor of cellular proliferation, attenuated low shear stress (SS) induced O2- production. Nevertheless, it is unclear whether autophagy plays a critical role in the regulation of eNOS uncoupling. Therefore, this study aimed to investigate the modulation of autophagy on eNOS uncoupling induced by low SS exposure. We found that low SS induced endothelial O2- burst, which was accompanied by reduced NO release. Furthermore, inhibition of eNOS by L-NAME conspicuously attenuated low SS-induced O2- releasing, indicating eNOS uncoupling. Autophagy markers such as LC3 II/I ratio, amount of Beclin1, as well as ULK1/Atg1 were increased during low SS exposure, whereas autophagic degradation of p62/SQSTM1 was markedly reduced, implying impaired autophagic flux. Interestingly, low SS-induced NO reduction could be reversed by rapamycin, WYE-354 or ATG5 overexpression vector via restoration of autophagic flux, but not by N-acetylcysteine or apocynin. eNOS uncoupling might be ascribed to autophagic flux blockade because phosphorylation of eNOS Thr495 by low SS or PMA stimulation was also regulated by autophagy. In contrast, eNOS acetylation was not found to be regulated by low SS and autophagy. Notably, although low SS had no influence on eNOS Ser1177 phosphorylation, whereas boosted eNOS Ser1177 phosphorylation by rapamycin were in favor of the eNOS recoupling through restoration of autophagic flux. Taken together, we reported a novel mechanism for regulation of eNOS uncoupling by low SS via autophagy-mediated eNOS phosphorylation, which is implicated in geometrical nature of atherogenesis.

Pericardial effusion is correlated with clinical outcome after pulmonary artery denervation for pulmonary arterial hypertension.

OBJECTIVES: Pericardial effusion (PE) is correlated with outcomes in patients with pulmonary arterial hypertension (PAH). Pulmonary artery denervation (PADN) was used for treatment of PAH. The present study aimed to analyze the prognostic value of PE for outcomes after PADN in patients with WHO Group I, Group II and Group IV PAH. RESULTS: PE, frequently seen in patients with connective tissue disease, was featured by fast heart rate, decreased exercise capacity, more syncope, worsening pulmonary arterial hemodynamic and right atrium size. PADN procedure resulted in dramatic reduction of PE. After a median of 376 days follow-up, the rate of PAH-related event, all-cause death and rehospitalization increased over the PE amount and occurred in 29.8%, 19.7% and 25.2% of patients with PE, different to 3.4%, 3.4% and 6.8% of patients without PE (p = 0.034, p = 0.041 and p = 0.039, respectively). The reduction of PE during follow-up was similar among three groups. MATERIALS AND METHODS: Between March 2012 and July 2014, a total of 66 consecutive patients (52 ± 16 years) who underwent PADN were stratified by no PE (n = 20), PE < 10 mm (n = 29) and PE ≥ 10 mm (n = 17) according to baseline echocardiograph. Dynamic change of PE and its correlation with PAH-related event after PADN were measured. CONCLUSIONS: PE is associated with increased PAH-related event after PADN. PADN results in significant similar reduction of PE among patients with Group I, Group II and Group IV PAH.

Spontaneous Coronary Artery Dissection as a Cause of Acute Myocardial Infarction in Young Female Population: A Single-center Study.

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is a nonatherosclerotic but a rare and extremely dangerous clinical entity, it has a high prevalence in young female population with acute myocardial infarction (AMI). The previous reports were restricted to other countries' population, but rare in China. Hence, this study aimed to focus on the characteristics of SCAD as a cause of young female AMI population in Jiangsu, China. METHODS: This study enrolled young female AMI patients aged ≤50 years who underwent coronary angiography (CAG) and intracoronary imaging in our center between January 2013 and December 2016. Their clinical presentations, risk factors, and CAG characteristics were analyzed. RESULTS: A total of 60 young female AMI (<7 days) patients were enrolled. From their CAG and intracoronary imaging results, the prevalence of SCAD in young female AMI population was 35% (21/60), the prevalence of coronary atherosclerostic heart disease was 65% (39/60). In the SCAD group, 43% (9/21) presented with non-ST-elevation myocardial infarction (NSTEMI) and the remainder presenting as STEMI. SCAD usually occurred in a single vessel (20/21, 95%), especially in left anterior descending artery (14/21, 67%). Eighteen patients (18/21, 86%) underwent conservative treatment, whereas the remaining three patients (3/21, 14%) underwent percutaneous coronary intervention. Regarding the angiographic results of SCAD lesions, intramural hematoma was discriminated in 95% (20/21), and Type I imaging was observed in 5% (1/21), Type II was observed in 67% (14/21), and Type III was 29% (6/21). The average stenosis in the group was 76.9% ± 20.6%, and the mean lesion length was 36.6 ± 8.6 mm. CONCLUSIONS: SCAD has a high prevalence in young female AMI population in Jiangsu, China. Discriminating the cause of AMI in young female population is very important.

Clinical Outcome of Double Kissing Crush Versus Provisional Stenting of Coronary Artery Bifurcation Lesions: The 5-Year Follow-Up Results From a Randomized and Multicenter DKCRUSH-II Study (Randomized Study on Double Kissing Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions).

BACKGROUND: Provisional stenting is effective for anatomic simple bifurcation lesions. Double kissing crush stenting reduces the 1-year rate of target lesion revascularization. This study aimed to investigate the 5-year clinical results of the DKCRUSH-II study (Randomized Study on Double Kissing Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions). METHODS AND RESULTS: A total of 370 patients with coronary bifurcation lesions who were randomly assigned to either the double kissing crush or provisional stenting group in the DKCRUSH-II study were followed for 5 years. The primary end point was the occurrence of a major adverse cardiac event at 5 years. Patients were classified by simple and complex bifurcation lesions according to the DEFINITION criteria (Definitions and Impact of Complex Bifurcation Lesions on Clinical Outcomes After Percutaneous Coronary Intervention Using Drug-Eluting Stents). At 5 years, the major adverse cardiac event rate (23.8%) in the provisional stenting group was insignificantly different to that of the double kissing group (15.7%; P=0.051). However, the difference in the target lesion revascularization rate between 2 groups was sustained through the 5-year follow-up (16.2% versus 8.6%; P=0.027). The definite and probable stent thrombosis rate was 2.7% in each group (P=1.0). Complex bifurcation was associated with a higher rate of target lesion revascularization (21.6%) at 5 years compared with 11.1% in patients with a simple bifurcation (P=0.037), with an extremely high rate in the provisional stenting group (36.8% versus 12.5%, P=0.005) mainly because of final kissing balloon inflation (19.4% versus 5.2%; P=0.036). CONCLUSIONS: The double kissing crush stenting technique for coronary bifurcation lesions is associated with a lower rate of target lesion revascularization. The optimal stenting approach based on the lesions' complexity may improve the revascularization for patients with complex bifurcations. CLINICAL TRIAL REGISTRATION: URL: http://www.chictr.org. Unique identifier: ChiCTR-TRC-0000015.

Pulmonary artery denervation improves pulmonary arterial hypertension induced right ventricular dysfunction by modulating the local renin-angiotensin-aldosterone system.

BACKGROUND: Pulmonary arterial hypertension (PAH) is commonly accompanied with the activation of the renin-angiotensin-aldosterone system (RAAS). Renal sympathetic denervation (RSD) reduces PAH partly through the inhibition of RAAS. Analogically, we hypothesized that pulmonary artery denervation (PADN) could reverse PAH and PAH-induced right ventricular (RV) dysfunction by downregulating the local RAAS activity. METHODS: Twenty-five beagle dogs were randomized into two groups: control group (intra-atrial injection of N-dimethylacetamide, 3 mg/kg, n = 6) and test group (intra-atrial injection of dehydrogenized-monocrotaline, 3 mg/kg, n = 19). Eight weeks later, dogs in the test group with mean pulmonary arterial pressure (mPAP) ≥25 mmHg (n = 16) were reassigned into the sham (n = 8) and PADN groups (n = 8) by chance. After another 6 weeks, the hemodynamics, pulmonary tissue morphology and the local RAAS expression in lung and right heart tissue were measured. RESULTS: PADN reduced the mPAP (25.94 ± 3.67 mmHg vs 33.72 ± 5.76 mmHg, P < 0.05) and the percentage of medial wall thickness (%MWT) (31.0 ± 2.6 % vs 37.9 ± 2.8 %, P < 0.05) compared with the sham group. PADN attenuated RV dysfunction, marked with reduced atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and ratio of right ventricular to left ventricular plus septum weight [RV/(LV + S)]. Moreover, the local RAAS expression was activated in PAH dogs while inhibited after PADN. CONCLUSIONS: PADN improves hemodynamics and relieves RV dysfunction in dogs with PAH, which can be associated with the downregulating RAAS activity in local tissue.

Pulmonary artery denervation for treatment of a patient with pulmonary hypertension secondary to left heart disease.

Pulmonary hypertension (PH) predicts poor outcome in patients with left heart disease. A 62-year-old man was referred for heart failure associated with ischemic cardiomyopathy. He received a diagnosis of combined postcapillary and precapillary PH secondary to left heart disease on the basis of hemodynamic parameters. After the pulmonary artery denervation procedure was performed, hemodynamic parameters were markedly improved, which resulted in a significant increase in functional capacity.

Hemodynamic, functional, and clinical responses to pulmonary artery denervation in patients with pulmonary arterial hypertension of different causes: phase II results from the Pulmonary Artery Denervation-1 study.

BACKGROUND: The mechanisms underlying pulmonary arterial hypertension (PAH) are multifactorial. The efficacy of pulmonary artery denervation (PADN) for idiopathic PAH treatment has been evaluated. This study aimed to analyze the hemodynamic, functional, and clinical responses to PADN in patients with PAH of different causes. METHODS AND RESULTS: Between April 2012 and April 2014, 66 consecutive patients with a resting mean pulmonary arterial pressure ≥25 mm Hg treated with PADN were prospectively followed up. Target drugs were discontinued after the PADN procedure. Hemodynamic response and 6-minute walk distance were repeatedly measured within the 1 year post PADN follow-up. The clinical end point was the occurrence of PAH-related events at the 1-year follow-up. There were no PADN-related complications. Hemodynamic success (defined as the reduction in mean pulmonary arterial pressure by a minimal 10% post PADN) was achieved in 94% of all patients, with a mean absolute reduction in systolic pulmonary arterial pressure and mean pulmonary arterial pressure within 24 hours of -10 mm Hg and -7 mm Hg, respectively. The average increment in 6-minute walk distance after PADN was 94 m. Worse PAH-related events occurred in 10 patients (15%), mostly driven by the worsening of PAH (12%). There were 8 (12%) all-cause deaths, with 6 (9%) PAH-related deaths. CONCLUSIONS: PADN was safe and feasible for the treatment of PAH. The PADN procedure was associated with significant improvements in hemodynamic function, exercise capacity, and cardiac function and with less frequent PAH-related events and death at 1 year after PADN treatment. Further randomized studies are required to confirm the efficacy of PADN for PAH. CLINICAL TRIAL REGISTRATION: URL: http://www.chictr.trc.com.cn. Unique identifier: chiCTR-ONC-12002085.

Rapamycin protects neurons from brain contusion­induced inflammatory reaction via modulation of microglial activation.

The inflammatory reaction is important in secondary injury following traumatic brain injury (TBI). Rapamycin has been demonstrated as a neuroprotective agent in a mouse model of TBI, however, there is a lack of data regarding the effects of rapamycin on the inflammatory reaction following TBI. Therefore, the present study was designed to assess the effects of treatment with rapamycin on inflammatory reactions and examine the possible involvement of microglial activation following TBI. Male imprinting control region mice were randomly divided into four groups: Sham group (n=23), TBI group (n=23), TBI + dimethyl sulfoxide (DMSO) group (n=31) and TBI + rapamycin group (n=31). Rapamycin was dissolved in DMSO (50 mg/ml) and injected 30 min after TBI (2 mg/Kg; intraperitoneally). A weight­drop model of TBI was induced, and the brain tissues were harvested 24 h after TBI. The findings indicated that the administration of rapamycin following TBI was associated with decreased levels of activated microglia and neuron degeneration at the peri­injury site, reduced levels of proinflammatory cytokines and increased neurobehavioral function, possibly mediated by inactivation of the mammalian target of rapamycin pathway. The results of the present study offer novel insight into the mechanisms responsible for the anti­neuroinflammatory effects of rapamycin, possibly involving the modulation of microglial activation.

Pulmonary Artery Denervation Attenuates Pulmonary Arterial Remodeling in Dogs With Pulmonary Arterial Hypertension Induced by Dehydrogenized Monocrotaline.

OBJECTIVES: This study aimed to investigate sympathetic nerve (SN) ultrastructural changes and hemodynamic and pulmonary artery (PA) pathological improvements by pulmonary arterial denervation (PADN) in animals with pulmonary arterial hypertension (PAH), as well as the underlying mechanisms. BACKGROUND: SN overactivity plays a role in PAH. Previous studies have reported short-term improvements in pulmonary arterial pressure (PAP) and cardiac function by PADN, but PA remodeling and the associated mechanisms remain unclear. METHODS: Forty dogs were randomly (ratio of 1:3) assigned to the control (intra-atrial injection of N-dimethylacetamide, 3 mg/kg) and test (intra-atrial injection of dehydrogenized-monocrotaline, 3 mg/kg) groups. After 8 weeks, the animals in the test group with a mean PAP >25 mm Hg (n = 20) were randomized (ratio of 1:1) into the sham and PADN groups. At 14 weeks, the hemodynamics, medial wall thickness and PA muscularization, and messenger ribonucleic acid expression of genes in lung tissues were measured. Another 35 PAH dogs were used to measure the SN conduction velocity, electron microscopic assessment, and nerve distribution. RESULTS: PADN induced significant SN demyelination and axon loss and slowed SN conduction velocity over time, with resulting profound reductions in the mean PAP (23.5 ± 2.3 mm Hg vs. 33.7 ± 5.8 mm Hg), pulmonary vessel resistance (3.5 ± 2.3 Wood units vs. 7.7 ± 1.7 Wood units), medial wall thickness (22.3 ± 3.3% vs. 30.4 ± 4.1%), and full muscularization (40.3 ± 9.3% vs. 57.1 ± 5.7%) and increased nonmuscularization (29.8 ± 6.1% vs. 12.9 ± 4.9%) compared with the Sham group (all p < 0.001). PADN inhibited the messenger ribonucleic acid expression of genes correlated with inflammation, proliferation, and vasoconstriction. CONCLUSIONS: PADN induces permanent SN injury and subsequent improvements in hemodynamics and PA remodeling in animals with PAH through mechanisms that may be experimentally and clinically beneficial.