Diagnostic and therapeutic algorithm for pulmonary arterial hypertension

At a crossroads: coronavirus disease 2019 recovery and the risk of pulmonary vascular disease

PURPOSE OF REVIEW

The coronavirus disease 2019 (COVID-19) pandemic has led to almost 3,000,000 deaths across 139 million people infected worldwide. Involvement of the pulmonary vasculature is considered a major driving force for morbidity and mortality. We set out to summarize current knowledge on the acute manifestations of pulmonary vascular disease (PVD) resulting from COVID-19 and prioritize long-term complications that may result in pulmonary hypertension (PH).

RECENT FINDINGS

Acute COVID-19 infection can result in widespread involvement of the pulmonary vasculature, myocardial injury, evidence of persistent lung disease, and venous thromboembolism. Post COVID-19 survivors frequently report ongoing symptoms and may be at risk for the spectrum of PH, including group 1 pulmonary arterial hypertension, group 2 PH due to left heart disease, group 3 PH due to lung disease and/or hypoxia, and group 4 chronic thromboembolic PH.

SUMMARY

The impact of COVID-19 on the pulmonary vasculature is central to determining disease severity. Although the long-term PVD manifestations of COVID-19 are currently uncertain, optimizing the care of risk factors for PH and monitoring for the development of PVD will be critical to reducing long-term morbidity and improving the health of survivors.

Pulmonary Arterial Hypertension in Indonesia: Current Status and Local Application of International Guidelines

Recent advances in the diagnosis and management of pulmonary arterial hypertension (PAH) have led to a significant improvement in the outcomes for patients with PAH. However, prompt and accurate diagnosis of PAH remains an unmet challenge due to lack of awareness and lack of meticulous data to profile the etiology and pathophysiology of this rare progressive disease, especially in low- and middle-income country. In Indonesia, the true prevalence and incidence of different subtypes of PAH in general population is still unknown. The Congenital HeARt Disease in adult and Pulmonary Hypertension (COHARD-PH) registry was the first single-center prospective registry in Indonesia, which indicated that almost 80% of adult patients with congenital heart disease (CHD) had experienced PAH and even Eisenmenger syndrome due to delayed diagnosis. Screening for early detection of asymptomatic CHD in children is yet to be systematically established in Indonesia, leading to undiagnosed and uncorrected CHD in adulthood. There are no specific national guidelines focusing on diagnostic workup and treatment of PAH in Indonesia. Furthermore, the lack of adequate diagnostic facilities, limited treatment availability, and limited drug coverage under the National Health Insurance Scheme are key issues that remain unaddressed. This review focuses on the diagnosis, treatment, and management of PAH associated with CHD in Indonesia as per international guidelines. We have proposed recommendations to effectively control and prevent PAH associated with CHD in Indonesia. The paper should be of interest to readers in the area of medical management and policy makers especially in low- and middle-income countries.

Transcriptomic profiles in pulmonary arterial hypertension associate with disease severity and identify novel candidate genes

Using RNAseq, we identified a 61 gene-based circulating transcriptomic profile most correlated with four indices of pulmonary arterial hypertension severity. In an independent dataset, 13/61 (21%) genes were differentially expressed in lung tissues of pulmonary arterial hypertension cases versus controls, highlighting potentially novel candidate genes involved in pulmonary arterial hypertension development.

Diabetes Mellitus Associates with Increased Right Ventricular Afterload and Remodeling in Pulmonary Arterial Hypertension

BACKGROUND

Diabetes mellitus is associated with left ventricular hypertrophy and dysfunction. Parallel studies have also reported associations between diabetes mellitus and right ventricular dysfunction and reduced survival in patients with pulmonary arterial hypertension. However, the impact of diabetes mellitus on the pulmonary vasculature has not been well characterized. We hypothesized that diabetes mellitus and hyperglycemia could specifically influence right ventricular afterload and remodeling in patients with Group I pulmonary arterial hypertension, providing a link to their known susceptibility to right ventricular dysfunction.

METHODS

Using an adjusted model for age, sex, pulmonary vascular resistance, and medication use, associations of fasting blood glucose, glycated hemoglobin, and the presence of diabetes mellitus were evaluated with markers of disease severity in 162 patients with pulmonary arterial hypertension.

RESULTS

A surrogate measure of increased pulmonary artery stiffness, elevated pulmonary arterial elastance (P = .012), along with reduced log(pulmonary artery capacitance) (P = .006) were significantly associated with the presence of diabetes mellitus in patients with pulmonary arterial hypertension in a fully adjusted model. Similar associations between pulmonary arterial elastance and capacitance were noted with both fasting blood glucose and glycated hemoglobin. Furthermore, right ventricular wall thickness on echocardiography was greater in pulmonary arterial hypertension patients with diabetes, supporting the link between right ventricular remodeling and diabetes.

CONCLUSION

Cumulatively, these data demonstrate that an increase in right ventricular afterload, beyond pulmonary vascular resistance alone, may influence right ventricular remodeling and provide a mechanistic link between the susceptibility to right ventricular dysfunction in patients with both diabetes mellitus and pulmonary arterial hypertension.

Identification of multiple ACVRL1 mutations in patients with pulmonary arterial hypertension by targeted exome capture

Pulmonary artery hypertension (PAH) is characterized as sustained elevation of pressure in the pulmonary vascular system that is attributable to a variety of causes. More than a dozen genes have previously been proposed as being associated with PAH. To examine potential mutations of these genes in patients with PAH, we developed a targeted exome kit containing 22 PAH-associated genes for genetic screens of 80 unrelated patients with PAH. As a result, we identified 16 different mutations in the BMPR2 gene and four different mutations in ACVRL1, the gene for activin receptor-like kinase-1 (ACVRL1). However, no deleterious mutations were found in the remaining 20 genes. In the present study, we provided detailed characterization of the ACVRL1 mutations in four pedigrees, including two novel missense mutations (c.676G>A, p.V226M; c.955G>C, p.G319R) and two recurrent mutations (c.1231C>T, p.R411W; c.1450C>T, p.R484W). Furthermore, we showed that markedly reduced Smad1/5 phosphorylation levels and reduced activities of luciferase reporters in each of the four ACVRL1 mutant-transfected NIH-3T3 cells. Therefore, our findings demonstrated that missense mutations of ACVRL1 identified in the present study significantly affected the bone morphogenetic protein 9 (BMP-9) pathway, implicating PAH pathogenesis. Detailed genotype–phenotype correlation analysis revealed initial symptoms of hereditary haemorrhagic telangiectasia (HHT) in some of the patients, suggesting the importance of sequencing molecular markers for early identification and intervention of individuals at risk for PAH and potential HHT. We developed a customized exome sequencing system to identify mutations in these PAH-associated genes, and found two novel missense mutations and two recurrent mutations in the ACVRL1 gene in four unrelated Chinese families; we also determined hypomorphic alleles using functional studies.

Gibbs J. The changing landscape of pulmonary arterial hypertension and implications for patient care

Registries have provided a wealth of information on the clinical and disease characteristics of patients living with pulmonary arterial hypertension (PAH) since the 1980s. Certain PAH demographics, such as the prevalence of various PAH subgroups and preponderance of female patients, appear to have remained stable over time. Contemporary registry data indicate that the average age of patients diagnosed with PAH has increased, at least in the Western world. Older patients with PAH are more likely to be diagnosed with a more advanced stage of the disease, have lower exercise capacity and present with multiple comorbidities. They also have worse survival compared with younger patients. Within the PAH population, there is also a subset of patients with a lower diffusing capacity of the lung for carbon monoxide who are generally older and display more severe disease characteristics. This review discusses the implications that the increased age of the PAH population at diagnosis has on the treatment and management of the disease, as well as the need for earlier and improved diagnosis in these patients.