In flow-associated pulmonary arterial hypertension (PAH), increased pulmonary blood flow is an essential trigger for neointimal formation. Using microarray analysis, we recently found that the early ...growth response protein 1 (Egr-1) transcription factor is increased in experimental flow-associated end-stage PAH. Its role in PAH development is unknown. Here, we assessed the spatiotemporal expression of Egr-1 during neointimal development in flow-associated PAH. Flow-associated PAH was produced in rats by combining monocrotaline administration with an aortocaval shunt. Animals were sacrificed 1 day before or 1 day, 1 week, or 4 to 5 weeks after flow addition. Egr-1 expression was spatiotemporally assessed using laser microdissection, quantitative real-time PCR and immunohistochemistry. In addition, Egr-1 expression was assessed in a non-neointimal pulmonary hypertension model and in human PAH associated with congenital shunt. In 4 to 5 weeks, rats subjected to increased flow developed PAH with neointimal lesions. Egr-1 mRNA was increased 1 day after flow addition and in end-stage PAH, whereas monocrotaline only did not result in increased Egr-1 mRNA. Directly after flow addition, Egr-1 was expressed in endothelial cells. During disease development, Egr-1 protein expression increased and migrated throughout the vessel wall. In PAH patients, Egr-1 was expressed in vessels with media hypertrophy and neointimal lesions, including plexiform lesions. Thus, Egr-1 may be an important regulator in the development of pulmonary neointimal lesions induced by increased pulmonary blood flow.
The goal of this study was to assess outcomes of patients who underwent implantation of left ventricular assist devices (LVADs) at nontransplantation mechanical circulatory support centers. As the ...availability of LVADs for advanced heart failure has expanded to nontransplantation mechanical circulatory support centers, concerns have been expressed about maintaining good outcomes. Demographics and outcomes were evaluated in 276 patients with advanced heart failure who underwent implantation of LVADs as bridge to transplantation or destination therapy at 27 open-heart centers. Baseline characteristics, operative mortality, length of stay, readmission rate, adverse events, quality of life, and survival were analyzed. The overall 30-day mortality was 3% (8 of 276), and survival rates at 6, 12, and 24 months, respectively, were 92 ± 2%, 88 ± 3%, and 84 ± 4% for the bridge-to-transplantation group and 81 ± 3%, 70 ± 5%, and 63 ± 6% for the destination therapy group, comparable with results published by the national Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS). The median length of stay for all patients was 21 days. Bleeding was the most frequent adverse event. Stroke occurred in 4% (bridge to transplantation) and 6% (destination therapy) of patients. Quality-of-life measures and 6-minute walk distances showed sustained improvements throughout support. In conclusion, outcomes with LVAD support at open-heart centers are acceptable and comparable with results from the INTERMACS registry. With appropriate teams, training, center commitment, and certification, LVAD therapy is being disseminated in a responsible way to open-heart centers.
Diabetes mellitus is associated with left-sided myocardial remodeling in heart failure with preserved ejection fraction (HFpEF). Little is known about the impact of diabetes mellitus on right ...ventricular (RV) function in HFpEF. We therefore studied the relation between diabetes mellitus and RV dysfunction in HFpEF. We have examined patients with HFpEF who underwent simultaneous right-sided cardiac catheterization and echocardiography. RV systolic function was assessed using multiple established echocardiographic parameters, and systolic dysfunction was present if ≥2 parameters were outside the normal range. RV diastolic function was assessed using the peak diastolic tissue velocity of the lateral tricuspid annulus (RV e') and was present if <8.0 cm/s. Diabetes mellitus was defined as a documented history of diabetes, a fasting glucose level of ≥7.0 mmol/L, a positive glucose intolerance test result, or a glycated hemoglobin level of ≥6.5%. A total of 91 patients were studied (mean age 74 ± 9 years, 69% women). A total of 37% had RV systolic dysfunction and 23% RV diastolic dysfunction. Thirty-seven percent of the patients had type 2 diabetes mellitus. These patients had higher pulmonary artery pressure (34 mm Hg vs 29 mm Hg, p = 0.004), more RV systolic dysfunction (57% vs 29%, p = 0.009), more RV diastolic dysfunction (46% vs 12%, p = 0.001), and lower RV e' (8.7 cm/s vs 11.5 cm/s, p = 0.006). The presence of diabetes mellitus was independently associated with RV systolic dysfunction (odds ratio 2.84, 95% confidence interval 1.09 to 7.40, p = 0.03) and with RV diastolic dysfunction (odds ratio 4.33, 95% confidence interval 1.25 to 15.07, p = 0.02), after adjustment for age, gender, and pulmonary pressures. In conclusion, diabetes mellitus is strongly associated with RV systolic and diastolic dysfunctions in patients with HFpEF, independent of RV afterload.
•Hemodynamic parameters obtained from 4D flow MRI are useful for risk stratification in MFS patients. Especially in combination with additional risk factors, such as male sex, and a HI mutation ...type.•Deviant directed WSS in the descending aorta was more frequently seen in male MFS patients, and patients with a HI mutation type.•60% of MFS patients with previous aortic root replacement showed abnormal hemodynamics in the ascending aorta.
It is difficult to assess the risk for aortic dissection beyond the aortic root in patients with Marfan syndrome (MFS). To aid risk assessment in these patients, we investigated aortic flow and wall shear stress (WSS) by 4D flow magnetic resonance imaging (MRI) in patients with MFS and compared the results with healthy volunteers. We hypothesized that MFS patients with a high-risk profile for aortic dissection would show abnormal hemodynamics in aortic regions associated with aortic dissection.
MFS patients (n = 55) and healthy subjects (n = 25), matched for age and sex, prospectively underwent 4D flow MRI. 4D flow maps were constructed to detect elevated (defined as higher than the three-dimensional 95 % confidence interval) and deviant directed (defined as vector angle differences higher than 120°) WSS in MFS patients as compared to the controls. Univariate and multivariate associations with risk factors for aortic dissection in MFS patients were assessed.
The maximum incidence for elevated WSS was 20 % (CI 9 %-31 %) and found in the ascending aorta. The maximum for deviant directed WSS was 39 % (CI 26 %-52 %) and found in the inner descending aorta. Significantly more male patients had deviant directed WSS in the inner proximal descending aorta (63 % vs 24 %, p = 0.014). Multivariate analysis showed that deviant directed WSS was associated with male sex (p = 0.019), and a haplo-insufficient FBN1 mutation type (p = 0.040). In 60 % of MFS patients with a previous aortic root replacement surgery, abnormal hemodynamics were found in the ascending aorta. No significant differences between hemodynamics were found in the descending aorta between operated and non-operated patients.
Deviant directed WSS in the proximal descending aorta is associated with known risk factors for aortic dissection in MFS patients, namely male sex and a haploinsufficient FBN1 mutation type.
Marfan syndrome (MFS) is a connective tissue disorder affecting the cardiovascular, ocular, and skeletal system, which may be accompanied by psychological features. This study aimed to determine the ...prevalence of fatigue, anxiety, and symptoms of depression in MFS patients, and to assess the degree to which sociodemographic and clinical variables are associated with fatigue and psychological aspects. The prevalence of fatigue, anxiety, and symptoms of depression were assessed in two cohorts of MFS patients and compared with healthy controls. The checklist individual strength (CIS), and hospital anxiety and depression scale (HADS) questionnaires were utilized. Medical status was assessed (family history of MFS, aortic root dilatation >40 mm, previous aortic surgery, aortic dissection, chronic pain, skeletal involvement, and scoliosis). Severe fatigue was experienced by 37% of the total MFS cohort (n = 155). MFS patients scored significantly higher on the CIS questionnaire, concerning severe fatigue, as compared with the general Dutch population (p < 0.0001). There were no differences in HADS anxiety or depression scores. In older MFS patients, with a more severe cardiovascular phenotype, chronic pain, and a higher unemployment rate, significantly more symptoms of depression were observed, when compared with the general population (p = 0.027) or compared with younger MFS patients (p = 0.026). Multivariate analysis, showed that anxiety was associated with chronic pain (p = 0.022) and symptoms of depression with unemployment (p = 0.024). MFS patients report significantly more severe fatigue as compared with the general population. Since the cause of fatigue is unclear, more research may be needed. Psychological intervention, for example, cognitive behavioral therapy, may contribute to a reduction in psychological symptoms.
Pulmonary arterial hypertension (PAH) is characterized by the development of unique neointimal lesions in the small pulmonary arteries, leading to increased right ventricular (RV) afterload and ...failure. Novel therapeutic strategies are needed that target these neointimal lesions. Recently, the transcription factor Egr-1 (early growth response protein 1) was demonstrated to be up-regulated early in experimental neointimal PAH. Its effect on disease development, however, is unknown. We aimed to uncover a novel role for Egr-1 as a molecular inductor for disease development in PAH.
In experimental flow-associated PAH in rats, we investigated the effects of Egr-1 down-regulation on pulmonary vascular remodelling, including neointimal development, and disease progression. Intravenous administration of catalytic oligodeoxynucleotides (DNA enzymes, DNAzymes) resulted in down-regulation of pulmonary vascular Egr-1 expression. Compared with vehicle or scrambled DNAzymes, DNAzymes attenuated pulmonary vascular remodelling, including the development of occlusive neointimal lesions. Selective down-regulation of Egr-1 in vivo led to reduced expression of vascular PDGF-B, TGF-β, IL-6, and p53, resulting in a reduction of vascular proliferation and increased apoptosis. DNAzyme treatment further attenuated pulmonary vascular resistance, RV systolic pressure, and RV hypertrophy. In contrast, in non-neointimal PH rodents, DNAzyme treatment had no effect on pulmonary vascular and RV remodelling. Finally, pharmacological inhibition of Egr-1 with pioglitazone, a peroxisome proliferator activated receptor-γ ligand, attenuated vascular remodelling including the development of neointimal lesions.
These results indicate that Egr-1 governs pulmonary vascular remodelling and the development of characteristic vascular neointimal lesions in flow-associated PAH. Egr-1 is therefore a potential target for future PAH treatment.
Aim
Right ventricular (RV) failure due to pressure or volume overload is a major risk factor for early mortality in congenital heart disease and pulmonary hypertension, but currently treatments are ...lacking. We aimed to demonstrate that the phosphodiesterase 5A inhibitor sildenafil can prevent adverse remodelling and improve function in chronic abnormal RV overload, independent from effects on the pulmonary vasculature.
Methods and results
In rat models of either pressure or volume overload, we performed pressure–volume studies to measure haemodynamic effects and voluntary exercise testing as clinical outcome after 4 weeks of sildenafil (or vehicle) administration. In the pressure‐loaded right ventricle, sildenafil enhanced contractility end‐systolic elastance (mmHg/mL) 247 ±68 vs.155 ±71, sildenafil vs. vehicle, P < 0.05, prevented RV dilatation end‐diastolic volume (μL) 733 ±50 vs. 874 ±39, P < 0.05, reduced wall stress peak wall stress (mmHg) 323 ±46 vs. 492 ±62, P < 0.05, and partially preserved exercise tolerance running distance (%) –33 ±15 vs. –62 ±12, P < 0.05. Protein kinase A was not activated by sildenafil and thus did not mediate the observed effects. In contrast, protein kinase G‐1 was activated by sildenafil, but hypertrophy was not inhibited. Importantly, sildenafil did not prevent diastolic dysfunction, whereas RV fibrosis appeared to be increased in sildenafil‐treated rats. In the volume‐loaded right ventricle, sildenafil treatment did not show any beneficial effects.
Conclusion
We demonstrate sildenafil to have beneficial, afterload‐independent effects on the pressure‐loaded right ventricle, but not on the volume‐loaded right ventricle. These results indicate that sildenafil may offer a specific treatment for the pressure‐loaded right ventricle, although persistent diastolic dysfunction and RV fibrosis could be of concern.
Abstract
Background
Platypnea orthodeoxia syndrome (POS) is a condition characterized by onset or worsening of dyspnoea and desaturation in upright position that is relieved by returning to a supine ...position. This case report illustrates a sudden onset of severe platypnea caused by compression of the right atrium (RA) due to aortic dilatation and unilateral diaphragmatic paralysis after a recent stroke.
Case summary
A 71-year-male patient with a medical history of recent stroke of the left hemisphere was referred to emergency department with acute dyspnoea. During observation in the emergency department, desaturation was noted in upright position. A contrast computed tomography excluded pulmonary embolism but revealed a dilated aortic root and an elevated right hemidiaphragm. The RA was compressed between these two structures (sandwiched). Given the clinical suspicion of a POS, a transoesophageal echocardiography was performed which confirmed the presence of a persistent foramen ovale (PFO) in supine position. In upright position, there was a torrential increase in right-to-left shunting. The PFO was closed using an Occlutech™ device. Directly after the procedure, the patient was symptom free.
Discussion
A rise in RA pressure or difference in flow pattern in the RA can make a PFO become symptomatic. Elevated RA pressure was ruled out. Most anatomical pathologies influencing the flow pattern develop slowly over time. This case shows a presentation of POS after a recent stroke possible due to change in anatomy because of right hemidiaphragm paralysis in combination with the aortic dilatation.
Abstract Background Right ventricular failure (RVF) due to pressure load is a major cause of death in congenital heart diseases and pulmonary hypertension. The mechanisms of RVF are unknown. We used ...an experimental approach based upon clinical signs of RVF to delineate functional and biological processes associated with RVF. Methods and results Wistar rats were subjected to a pulmonary artery banding (PAB n = 12) or sham surgery (CON, n = 7). After 52 ± 5 days, 5/12 PAB rats developed clinical symptoms of RVF (inactivity, ruffled fur, dyspnea, ascites) necessitating termination (PAB + CF). We compared these to PAB rats with RVF without clinical symptoms (PAB−). PAB resulted in reduced cardiac output, RV stroke volume, TAPSE, and increased end diastolic pressure (all p < 0.05 vs. CON) in all rats, but PAB + CF rats were significantly more affected than PAB −, despite similar pressure load (p = ns). Pressure –volume analysis showed enhanced contractility (end systolic elastance) in PAB− and PAB + CF, but diastolic function (end diastolic elastance, end diastolic pressure) deteriorated especially in PAB + CF. In PAB + CF capillary density was lower than in PAB −. Gene-array analysis revealed downregulation of both fatty acid oxidation and carbohydrate metabolism in PAB + CF. Conclusion Chronic PAB led to different degrees of RVF, with half of the rats developing severe clinical symptoms of RVF, associated with progressive deterioration of diastolic function, hypoxia-prone myocardium, increased response to oxidative stress and suppressed myocardial metabolism. This model represents clinical RVF and allows for unraveling of mechanisms involved in the progression from RV adaptation to RV failure and the effect of intervention on these mechanisms.
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