Pulmonary Arterial Hypertension in Women

Pulmonary hypertension and insulin resistance: a mechanistic overview

Pulmonary arterial hypertension (PAH) is a vascular remodeling disease, characterized by increased blood pressure levels in pulmonary circulation, leading to a restriction in the circulation flow and heart failure. Although the emergence of new PAH therapies has increased survival rates, this disease still has a high mortality and patients that receive diagnosis die within a few years. The pathogenesis of PAH involves multiple pathways, with a complex interaction of local and distant cytokines, hormones, growth factors, and transcription factors, leading to an inflammation that changes the vascular anatomy in PAH patients. These abnormalities involve more than just the lungs, but also other organs, and between these affected organs there are different metabolic dysfunctions implied. Recently, several publications demonstrated in PAH patients a disturbance in glucose metabolism, demonstrated by higher levels of glucose, insulin, and lipids in those patients. It is possible that a common molecular mechanism can have a significant role in this connection. In this regard, this narrative review intends to focus on the recent papers that mainly discuss the molecular determinants between insulin resistance (IR) associated PAH, which included obesity subclinical inflammation induced IR, PPAR gamma and Adiponectin, BMPR2, mitochondrial dysfunction and endoplasmic reticulum stress. Therefore, the following review will summarize some of the existing data for IR associated PAH, focusing on the better understanding of PAH molecular mechanisms, for the development of new translational therapies.

A claims-based, machine-learning algorithm to identify patients with pulmonary arterial hypertension

Many patients with pulmonary arterial hypertension (PAH) experience substantial delays in diagnosis, which is associated with worse outcomes and higher costs. Tools for diagnosing PAH sooner may lead to earlier treatment, which may delay disease progression and adverse outcomes including hospitalization and death. We developed a machine-learning (ML) algorithm to identify patients at risk for PAH earlier in their symptom journey and distinguish them from patients with similar early symptoms not at risk for developing PAH. Our supervised ML model analyzed retrospective, de-identified data from the US-based Optum® Clinformatics® Data Mart claims database (January 2015 to December 2019). Propensity score matched PAH and non-PAH (control) cohorts were established based on observed differences. Random forest models were used to classify patients as PAH or non-PAH at diagnosis and at 6 months prediagnosis. The PAH and non-PAH cohorts included 1339 and 4222 patients, respectively. At 6 months prediagnosis, the model performed well in distinguishing PAH and non-PAH patients, with area under the curve of the receiver operating characteristic of 0.84, recall (sensitivity) of 0.73, and precision of 0.50. Key features distinguishing PAH from non-PAH cohorts were a longer time between first symptom and the prediagnosis model date (i.e., 6 months before diagnosis); more diagnostic and prescription claims, circulatory claims, and imaging procedures, leading to higher overall healthcare resource utilization; and more hospitalizations. Our model distinguishes between patients with and without PAH at 6 months before diagnosis and illustrates the feasibility of using routine claims data to identify patients at a population level who might benefit from PAH-specific screening and/or earlier specialist referral.

The Glycobiology of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a progressive pulmonary vascular disease of complex etiology. Cases of PAH that do not receive therapy after diagnosis have a low survival rate. Multiple reports have shown that idiopathic PAH, or IPAH, is associated with metabolic dysregulation including altered bioavailability of nitric oxide (NO) and dysregulated glucose metabolism. Multiple processes such as increased proliferation of pulmonary vascular cells, angiogenesis, apoptotic resistance, and vasoconstriction may be regulated by the metabolic changes demonstrated in PAH. Recent reports have underscored similarities between metabolic abnormalities in cancer and IPAH. In particular, increased glucose uptake and altered glucose utilization have been documented and have been linked to the aforementioned processes. We were the first to report a link between altered glucose metabolism and changes in glycosylation. Subsequent reports have highlighted similar findings, including a potential role for altered metabolism and aberrant glycosylation in IPAH pathogenesis. This review will detail research findings that demonstrate metabolic dysregulation in PAH with an emphasis on glycobiology. Furthermore, this report will illustrate the similarities in the pathobiology of PAH and cancer and highlight the novel findings that researchers have explored in the field.

Heart-lung transplantation for idiopathic pulmonary arterial hypertension and giant pulmonary artery aneurysm - case report

Backgound

Idiopathic pulmonary arterial hypertension (IPAH) is a rare condition that requires lung transplantation in patients’ refractory to medical therapy. Pulmonary artery aneurysm (PAA) is a documented complication of IPAH however, optimal management and timing of intervention for this rare entity is not well understood.

Case report

We report a case of a 51-year-old female who underwent heart-lung transplantation for IPAH and giant PAA. The extreme size of the PAA and underlying pathology encountered in this case precluded both lung transplantation and conventional aneurysm repair.

Conclusion

This case demonstrates that heart-lung transplantation is a good surgical option for IPAH complicated by giant sized PAA and right heart failure.

The Role of Estrogen Receptors in Cardiovascular Disease

Cardiovascular Diseases (CVDs) are the leading cause of death globally. More than 17 million people die worldwide from CVD per year. There is considerable evidence suggesting that estrogen modulates cardiovascular physiology and function in both health and disease, and that it could potentially serve as a cardioprotective agent. The effects of estrogen on cardiovascular function are mediated by nuclear and membrane estrogen receptors (ERs), including estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), and G-protein-coupled ER (GPR30 or GPER). Receptor binding in turn confers pleiotropic effects through both genomic and non-genomic signaling to maintain cardiovascular homeostasis. Each ER has been implicated in multiple pre-clinical cardiovascular disease models. This review will discuss current reports on the underlying molecular mechanisms of the ERs in regulating vascular pathology, with a special emphasis on hypertension, pulmonary hypertension, and atherosclerosis, as well as in regulating cardiac pathology, with a particular emphasis on ischemia/reperfusion injury, heart failure with reduced ejection fraction, and heart failure with preserved ejection fraction.

Correlation of acute pulmonal embolism with D-dimer levels and the diameter of the pulmonary trunk in thoracic multislice computed tomography. A single-centre retrospective analysis of 100 patients

Purpose

The aim of this retrospective study was to evaluate the correlation between D-dimer levels in positive thromboembolic thoracic computed tomography (CT) with the diameter of the pulmonary trunk and to study the relation between the D-dimer and the uni- or bilateralism of the lesions and the presence of pulmonal trunk involvement. We also analysed gender-specific differences in patients with and without dilatation of the pulmonal trunk.

Material and methods

A total of 100 acute care patients (50 men and 50 women) with positive thromboembolic multiple detector computed tomography of the thorax, performed on two modern CT scanners, were retrospectively studied. All thoracic CTs were evaluated by two expert radiologists, with attention paid to the diameter of the pulmonary trunk and the correlation of D-dimer level with the uni-or bilateralism of the lesions. We also analysed sex-specific correlations. All patients underwent multislice computed tomography-examination after applying 70 ml iodinated non-ionic contrast media. Graphpad Prism 8.1.1 software was used for statistical data.

Results

The "strongest" weak correlation resulted between D-dimer levels and the axial diameter of the pulmonal trunk. Considering the correlation between the axial diameter of the pulmonal trunk and gender-related distributions, we found that female patients had higher axial diameters than men. Another weak relationship, almost zero, was found between the D-dimer level and gender. Regarding the correlation between the uni- or bilateralism of thromboembolism and the D-dimer levels, we also found a weak correlation.

Conclusions

This retrospective study showed that D-dimer levels, the diameter of the pulmonal trunk, the location, and gender-related distributions have almost no correlation and are not significantly predictive in imaging.