Abstract Background Pulmonary hypertension and associated right ventricular (RV) dysfunction are important determinants of morbidity and mortality, which are optimally characterized by invasive ...hemodynamic measurements. Objectives This study sought to determine whether metabolite profiling could identify plasma signatures of right ventricular-pulmonary vascular (RV-PV) dysfunction. Methods We measured plasma concentrations of 105 metabolites using targeted mass spectrometry in 71 individuals (discovery cohort) who underwent comprehensive physiological assessment with right-sided heart catheterization and radionuclide ventriculography at rest and during exercise. Our findings were validated in a second cohort undergoing invasive hemodynamic evaluations (n = 71), as well as in an independent cohort with or without known pulmonary arterial (PA) hypertension (n = 30). Results In the discovery cohort, 21 metabolites were associated with 2 or more hemodynamic indicators of RV-PV function (i.e., resting right atrial pressure, mean PA pressure, pulmonary vascular resistance PVR, and PVR and PA pressure-flow response ΔPQ during exercise). We identified novel associations of RV-PV dysfunction with circulating indoleamine 2,3-dioxygenase (IDO)–dependent tryptophan metabolites (TMs), tricarboxylic acid intermediates, and purine metabolites and confirmed previously described associations with arginine–nitric oxide metabolic pathway constituents. IDO-TM levels were inversely related to RV ejection fraction and were particularly well correlated with exercise PVR and ΔPQ. Multisite sampling demonstrated transpulmonary release of IDO-TMs. IDO-TMs also identified RV-PV dysfunction in a validation cohort with known risk factors for pulmonary hypertension and in patients with established PA hypertension. Conclusions Metabolic profiling identified reproducible signatures of RV-PV dysfunction, highlighting both new biomarkers and pathways for further functional characterization.
Sudden Vision Loss Nair, Archana A; Pugh, Meredith E; Cherney, Edward F
JAMA ophthalmology,
05/2024, Letnik:
142, Številka:
5
Journal Article
Recenzirano
A 37-year-old woman was referred for evaluation of a retinal detachment in her left eye. Posterior examination results demonstrated a retinal detachment in the posterior pole with shifting fluid and ...no identifiable retinal break, and there was a thickened choroid with a hyporeflective band on ultrasound biomicroscopy. What would you do next?
Pulmonary arterial hypertension (PAH) is a deadly disease with no cure. Alternate conversion of angiotensin II (AngII) to angiotensin-(1-7) (Ang-(1-7)) by angiotensin-converting enzyme 2 (ACE2) ...resulting in Mas receptor (Mas1) activation improves rodent models of PAH. Effects of recombinant human (rh) ACE2 in human PAH are unknown. Our objective was to determine the effects of rhACE2 in PAH.We defined the molecular effects of Mas1 activation using porcine pulmonary arteries, measured AngII/Ang-(1-7) levels in human PAH and conducted a phase IIa, open-label pilot study of a single infusion of rhACE2 (GSK2586881, 0.2 or 0.4 mg·kg
intravenously).Superoxide dismutase 2 (SOD2) and inflammatory gene expression were identified as markers of Mas1 activation. After confirming reduced plasma ACE2 activity in human PAH, five patients were enrolled in the trial. GSK2586881 was well tolerated with significant improvement in cardiac output and pulmonary vascular resistance. GSK2586881 infusion was associated with reduced plasma markers of inflammation within 2-4 h and increased SOD2 plasma protein at 2 weeks.PAH is characterised by reduced ACE2 activity. Augmentation of ACE2 in a pilot study was well tolerated, associated with improved pulmonary haemodynamics and reduced markers of oxidant and inflammatory mediators. Targeting this pathway may be beneficial in human PAH.
Abstract Chronic, unresolved thromboemboli are an important cause of pulmonary hypertension (PH) with specific treatment strategies differing from other types of PH. Chronic thromboembolic pulmonary ...hypertension (CTEPH) is classified as Group 4 PH by the World Health Organization. It is a rare, but underdiagnosed, complication of acute pulmonary embolism that does not resolve and results in occlusion of large pulmonary arteries with a fibro-thrombotic material. The etiology of CTEPH remains uncertain, and it is unknown why certain patients with acute pulmonary embolism develop this disorder. The evaluation for CTEPH is an important part of the evaluation for PH in general, and it is crucial not to overlook this diagnosis as it is the only form of PH that is potentially curable. Patients diagnosed with CTEPH should be referred to an expert center for consideration of pulmonary endarterectomy, surgical removal of the chronic thromboembolic material. Not all patients with CTEPH are surgical candidates, however, and there are emerging treatments -medical therapy and balloon pulmonary angioplasty- that have shown benefit in this patient population. Without treatment, CTEPH can lead to progressive pulmonary vascular obstruction, right heart failure, and death. Thus, it is important for clinicians to recognize this subtype of PH. In this review, we providing overview of current understanding of the pathogenesis of CTEPH and highlight recommendations and recent advances in the evaluation and treatment of CTEPH.
BACKGROUND Pulmonary hypertension (PH) is common in elderly patients, but a detailed analysis of the causes of PH in the elderly has not been performed. We hypothesized that pulmonary arterial ...hypertension (PAH) is rare in elderly patients and sought to describe the characteristics of these patients at a large referral center. METHODS Clinical and hemodynamic data were collected on consecutive patients ≥ 65 years of age referred for evaluation of PH. The subtype of PH was determined after standard evaluation using the World Health Organization (WHO) classification. Patients with PH not meeting criteria for PAH with “out-of-proportion” PH related to group 2 or group 3 disease were classified as “other/mixed PH.” A model using age, presence of connective tissue disease, and left atrial size was developed to predict the probability of PAH diagnosis. RESULTS Two hundred forty-six elderly patients were evaluated (mean age, 72.9 ± 5.5 years, 78% women); 36 had PAH (15%). Idiopathic PAH was rare (four patients, 1.6%). WHO group 2 PH was the most frequent diagnosis (n = 70, 28% of cohort); mixed/other PH (n = 43, 17%) and WHO group 3 PH (n = 34, 14%) were also common diagnoses. Connective tissue disease strongly predicted PAH diagnosis (OR, 27.2; 95% CI, 9.5-77.6). CONCLUSIONS PAH is an uncommon cause of PH in elderly patients, most frequently associated with connective tissue disease. WHO group 2 PH and mixed disease are common, highlighting a need for careful phenotyping of elderly patients with PH prior to initiating PAH therapy.
Background The 6-min walk test, commonly used to assess exercise capacity and response to therapy in pulmonary arterial hypertension (PAH), has many well-described limitations. Sedentary time is ...associated with adverse cardiovascular outcomes and reduced quality of life, and measuring sedentary time and physical activity using accelerometry is another potential way to quantify exercise capacity in PAH. Whether sedentary time is different in patients with PAH vs control subjects is unknown. Methods Physical activity was measured in 20 patients with PAH and 30 matched healthy control subjects using accelerometry for 7 consecutive days. Patients with PAH completed standard 6-min walk testing, and baseline demographics were recorded for all study participants. Total daily activity counts, sedentary time, and proportion of time at various activity levels were compared between groups. Results Sedentary time was significantly higher in patients with PAH (mean, 92.1% daily activity; 95% CI, 89.5-94.8%) than in control subjects (mean, 79.9% daily activity; 95% CI, 76.4%–83.5%; P < .001), and all levels of physical activity were reduced in the PAH group compared with the control group ( P < .01 for all). Daily moderate to vigorous physical activity was reduced in the PAH group (7.5 min; 95% CI; 0.8-15.6 min) compared with the control group (mean, 64.7 min; 95% CI, 51.1-78.2 min; P < .001). Activity counts correlated with 6-min walk distance in the PAH group (Spearman rank correlation = 0.72, P < .001). Conclusions Sedentary time is increased in patients with PAH and may lead to increased risk for metabolic and cardiovascular morbidity. Quantitation of daily activity and sedentary time using accelerometry may be a novel end point for PAH management and clinical trials.
Determining the cause for pulmonary hypertension is difficult in many patients. Pulmonary arterial hypertension (PAH) is differentiated from pulmonary venous hypertension (PVH) by a wedge pressure ...(PWP)>15 mm Hg in PVH. Patients undergoing right heart catheterization for evaluation of pulmonary hypertension may be dehydrated and have reduced intravascular volume, potentially leading to a falsely low measurement of PWP and an erroneous diagnosis of PAH. We hypothesized that a fluid challenge during right heart catheterization would identify occult pulmonary venous hypertension (OPVH).
We reviewed the results of patients undergoing fluid challenge in our pulmonary hypertension database from 2004 to 2011. Baseline hemodynamics were obtained and repeated after infusion of 0.5 L of normal saline for 5 to 10 minutes. Patients were categorized as OPVH if PWP increased to >15 mm Hg after fluid challenge. Baseline hemodynamics in 207 patients met criteria for PAH. After fluid challenge, 46 patients (22.2%) developed a PWP>15 mm Hg and were reclassified as OPVH. Patients with OPVH had a greater increase in PWP compared with patients with PAH, P<0.001, and their demographics and comorbid illnesses were similar to patients with PVH. There were no adverse events related to fluid challenge.
Fluid challenge at the time of right heart catheterization is easily performed, safe, and identifies a large group of patients diagnosed initially with PAH, but for whom OPVH contributes to pulmonary hypertension. These results have implications for therapeutic trials in PAH and support the routine use of fluid challenge during right heart catheterization in patients with risk factors for PVH.
BACKGROUND—The mechanisms of right ventricular (RV) failure in pulmonary arterial hypertension (PAH) are poorly understood. Abnormalities in fatty acid (FA) metabolism have been described in ...experimental models of PAH, but systemic and myocardial FA metabolism has not been studied in human PAH.
METHODS AND RESULTS—We used human blood, RV tissue, and noninvasive imaging to characterize multiple steps in the FA metabolic pathway in PAH subjects and controls. Circulating free FAs and long-chain acylcarnitines were elevated in PAH patients versus controls. Human RV long-chain FAs were increased and long-chain acylcarnitines were markedly reduced in PAH versus controls. With the use of proton magnetic resonance spectroscopy, in vivo myocardial triglyceride content was elevated in human PAH versus controls (1.4±1.3% triglyceride versus 0.22±0.11% triglyceride, P=0.02). Ceramide, a mediator of lipotoxicity, was increased in PAH RVs versus controls. Using an animal model of heritable PAH, we demonstrated reduced FA oxidation via failure of palmitoylcarnitine to stimulate oxygen consumption in the PAH RV.
CONCLUSIONS—Abnormalities in FA metabolism can be detected in the blood and myocardium in human PAH and are associated with in vivo cardiac steatosis and lipotoxicity. Murine data suggest that lipotoxicity may arise from reduction in FA oxidation.
Extracorporeal membrane oxygenation (ECMO) is given to individuals with severe acute respiratory distress syndrome (ARDS). (1) Extracorporeal membrane oxygenation (ECMO) may help with survival. ...During the coronavirus disease pandemic (COVID-19), the The number of COVID-19 patients referred for ECMO has outstripped the ability of specialized hospitals to perform the treatment (2, 3). Patients with COVID-19 who are eligible for ECMO but do not undergo it. Not because of a lack of capacity in the health-care system. There were 26 patients (10.8 percent) who did not complete the referral evaluation, 44 (18.3%) who did not meet the severity of lung injury criteria, 80 (33.3%) who had one or more absolute contraindications or more than three relative contraindications, and 90 patients (37.5%) who were determined to be medically eligible.
Animal and human data suggest insulin resistance is common in pulmonary arterial hypertension (PAH). Although routine assessment of insulin resistance is difficult, hemoglobin A(1c) (HbA(1c)) is a ...sensitive test to detect diabetes mellitus (DM) and those at high risk for DM. We aimed to define the prevalence of elevated HbA(1c) in PAH patients and to correlate HbA(1c) levels with functional assessment.
HbA(1c) was measured in 41 PAH patients without a diagnosis of DM, along with demographic, functional, and hemodynamic data. Using published criteria, HbA(1c) ≤ 5.9% defined normal, 6.0% to 6.4% was glucose intolerance, and ≥ 6.5% was DM.
Twenty-three patients (56%) had HbA(1c) ≥ 6.0%, and 6 (15%) had unrecognized DM (HbA(1c) ≥ 6.5%). Age and body mass index were similar in patients with HbA(1c) ≥ 6.0% vs < 6.0%. There was a trend towards lower mean 6-minute walk distance in patients with elevated HbA(1c) (331.0 ± 126.6 vs 413.6 ± 74.9 meters, p = 0.07). The 6-month event-free survival was not significantly different in patients with elevated HbA(1c).
Unrecognized glucose intolerance as assessed by HbA(1c) is common in PAH. Further studies are needed to discern if glucose or insulin dysregulation mediates PAH pathogenesis or is secondary to advanced PAH.
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