Pulmonary arterial enlargement and acute exacerbations of COPD

Right cardiac involvement in lung diseases: a multimodality approach from diagnosis to prognostication

Lung diseases are amongst the main healthcare issues in the general population, having a high burden of morbidity and mortality. The cardiovascular system has a key role in patients affected by respiratory disorders. More specifically, the right ventricle (RV) enables the impaired lung function to be overcome in an initial stage of disease process, reducing the severity of dyspnoea. In addition, two of the main causes of death in this setting are RV failure and sudden cardiac death (SCD). Echocardiography is regarded as a useful and easily available tool in assessing RV function. Several noninvasive echocardiographic parameters of elevated pulmonary pressures and RV function have been proposed. The combination of different parameters and imaging methods is paramount and researches regarding RV impairment using these indices has been specifically addressed in relation to the chronic obstructive and restrictive lung disease in order to guide the clinicians in the management of these patients. Cardiac involvement in lung diseases is often observed, and RV changes are reported also in early stages of pulmonary diseases. The role of right ventricle in chronic respiratory disease patients has to be evaluated in detail to describe the response to therapy and the degree of disease progression through multimodality and advanced imaging techniques. The aim of this review is to describe the different pathophysiological mechanisms of cardiac impairment in primary lung disease (such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF) and sarcoidosis) and to summarize the role of cardiac multimodality imaging in the diagnosis and the prognosis of these diseases.

Unmet needs in the management of exacerbations of chronic obstructive pulmonary disease

Exacerbations of chronic obstructive pulmonary disease (COPD) are episodes of acute worsening of respiratory symptoms that require additional therapy. These events play a pivotal role in the natural course of the disease and are associated with a progressive decline in lung function, reduced health status, a low physical activity level, tremendous health care costs, and increased mortality. Although most exacerbations have an infectious origin, the underlying mechanisms are heterogeneous and specific predictors of their occurrence in individual patients are currently unknown. Accurate prediction and early diagnosis of exacerbations is essential to develop novel targets for prevention and personalized treatments to reduce the impact of these events. Several potential biomarkers have previously been studied, these however lack specificity, accuracy and do not add value to the available clinical predictors. At present, microbial composition and host-microbiome interactions in the lung are increasingly recognized for their role in affecting the susceptibility to exacerbations, and may steer towards a novel direction in the management of COPD exacerbations. This narrative review describes the current challenges and unmet needs in the management of acute exacerbations of COPD. Exacerbation triggers, biological clusters, current treatment strategies, and their limitations, previously studied biomarkers and prediction tools, the lung microbiome and its role in COPD exacerbations as well as future directions are discussed.

The m6A methyltransferase METTL3 promotes hypoxic pulmonary arterial hypertension

AIMS

N⁶-methyladenosine (m⁶A) is the most prevalent internal chemical RNA modification in mammal mRNAs. Accumulating evidence has shown the critical role of m⁶A in cardiovascular diseases including cardiac hypertrophy, heart failure, ischemic heart disease, vascular calcification, restenosis, and aortic aneurysm. However, whether m⁶A participates in the occurrence and development of hypoxic pulmonary hypertension (HPH) remains largely unknown. The present study aims to explore the role of key transferase METTL3, in the development of HPH.

MATERIALS AND METHODS

Pulmonary artery smooth muscle cells (PASMCs) and hypoxic rat models were used to research the METTL3-mediated m⁶A in HPH. EdU, transwell and TUNEL were performed to evaluate the proliferation, migration and apoptosis rates. m⁶A RNA Methylation Quantification Kit and m⁶A-qPCR were utilized to measure the total m⁶A level and m⁶A level of PTEN mRNA. RNA immunoprecipitation was used to detect the interaction between METTL3 and PTEN mRNA.

KEY FINDINGS

Both METTL3 mRNA and protein were found abnormally upregulated in vivo and in vitro. Furthermore, downregulation of METTL3 attenuated PASMCs proliferation and migration. In addition, m⁶A binding protein YTHDF2 was found significantly increased in PASMCs under hypoxia. YTHDF2 recognized METTL3 mediated m⁶A modified PTEN mRNA and promoted the degradation of PTEN. Decreased PTEN led to over-proliferation of PASMCs through activation of PI3K/Akt signaling pathway.

SIGNIFICANCE

METTL3/YTHDF2/PTEN axis exerts a significant role in hypoxia induced PASMCs proliferation, providing a novel therapeutic target for HPH.

Our current understanding of and approach to the management of lung cancer with pulmonary hypertension

INTRODUCTION

Lung cancer is a frequent pathology for which the best curative treatment is pulmonary resection. Pulmonary arterial hypertension is a rare disease but pulmonary hypertension associated with parenchymal disease or left heart disease is frequently observed in these patients. The diagnosis of pulmonary hypertension before lung resection makes the perioperative management of these patients more difficult and sometimes leads to rejecting patients for surgery.

AREAS COVERED

We performed a review of literature on PubMed on Pulmonary hypertension associated lung resection, preoperative assessment of lung resection and perioperative management of PH patients, including guidelines and clinical trials.In this review, we summarize the current state of knowledge regarding the pre and perioperative management of patients with suspected or confirmed PH who can benefit from surgical treatment of lung cancer.

EXPERT OPINION

Management of PH patients before lung resection should include a very careful workup including at least right heart catheterization with evaluation of the targeted PH treatment in an expert center and evaluation of other comorbidities. Perioperative management must be carried out in a specialized center.

The Challenge to Decide between Pulmonary Hypertension Due to Chronic Lung Disease and PAH with Chronic Lung Disease

Chronic lung diseases are strongly associated with pulmonary hypertension (PH), and even mildly elevated pulmonary arterial pressures are associated with increased mortality. Chronic obstructive pulmonary disease (COPD) is the most common chronic lung disease, but few of these patients develop severe PH. Not all these pulmonary pressure elevations are due to COPD, although patients with severe PH due to COPD may represent the largest subgroup within patients with COPD and severe PH. There are also patients with left heart disease (group 2), chronic thromboembolic disease (group 4, CTEPH) and pulmonary arterial hypertension (group 1, PAH) who suffer from COPD or another chronic lung disease as co-morbidity. Because therapeutic consequences very much depend on the cause of pulmonary hypertension, it is important to complete the diagnostic procedures and to decide on the main cause of PH before any decision on PAH drugs is made. The World Symposia on Pulmonary Hypertension (WSPH) have provided guidance for these important decisions. Group 2 PH or complex developmental diseases with elevated postcapillary pressures are relatively easy to identify by means of elevated pulmonary arterial wedge pressures. Group 4 PH can be identified or excluded by perfusion lung scans in combination with chest CT. Group 1 PAH and Group 3 PH, although having quite different disease profiles, may be difficult to discern sometimes. The sixth WSPH suggests that severe pulmonary hypertension in combination with mild impairment in the pulmonary function test (FEV1 > 60 and FVC > 60%), mild parenchymal abnormalities in the high-resolution CT of the chest, and circulatory limitation in the cardiopulmonary exercise test speak in favor of Group 1 PAH. These patients are candidates for PAH therapy. If the patient suffers from group 3 PH, the only possible indication for PAH therapy is severe pulmonary hypertension (mPAP ≥ 35 mmHg or mPAP between 25 and 35 mmHg together with very low cardiac index (CI) < 2.0 L/min/m²), which can only be derived invasively. Right heart catheter investigation has been established nearly 100 years ago, but there are many important details to consider when reading pulmonary pressures in spontaneously breathing patients with severe lung disease. It is important that such diagnostic procedures and the therapeutic decisions are made in expert centers for both pulmonary hypertension and chronic lung disease.

Association between ratio for diameters of pulmonary artery to ascending aorta bifurcation in chest CT scan and number of involved vessels in coronary angiography

Objective

Coronary artery disease (CAD) is an important cause of mortality and morbidity, therefore, recognizing its severity and related factors is important. This study was performed to evaluate the association between ratio for diameters of pulmonary artery to ascending aorta bifurcation in chest CT scan and number of involved vessels in coronary angiography. In this observational cross-sectional comparative study, 110 patients who were under coronary angiography in Firoozgar Hospital in 2017 were enrolled, and the association between ratio for diameters of pulmonary artery to ascending aorta bifurcation in their chest CT scan and number of involved vessels in angiography were assessed.

Results

In this study, number of involved vessels in angiography was related to PA/Ao ratio (P = 0.001) and further vessels were accompanied with higher ratio. It may be concluded that, a higher ratio for diameters of pulmonary artery to ascending aorta bifurcation in chest CT scan is related to higher number of involved vessels in coronary angiography, and it may have a predictive role.

Added benefits of early detection of other diseases on low-dose CT screening

Low-dose CT screening for lung cancer provides images of the entire chest and upper abdomen. While the focus of screening is on finding early lung cancer, radiology leadership has embraced the fact that the information contained in the images presents a new challenge to the radiology profession. Other findings in the chest and upper abdomen were not the reason for obtaining the screening CT scan, nor symptom-prompted, but still need to be reported. Reporting these findings and making recommendations for further workup requires careful consideration to avoid unnecessary workup or interventions while still maximizing the benefit that early identification of these other diseases provided. Other potential findings, such as cardiovascular disease and chronic pulmonary obstructive diseases actually cause more deaths than lung cancer. Existing recommendations for workup of abnormal CT findings are based on symptom-prompted indications for imaging. These recommendations may be different when the abnormalities are identified in asymptomatic people undergoing CT screening for lung cancer. I-ELCAP, a large prospectively collected multi-institutional and multi-national database of screenings, was used to analyze CT findings identified in screening for lung cancer. These analyses and recommendations were made by radiologists in collaboration with clinicians in different medical specialties.

Nocturnal Hypoxemia and CT Determined Pulmonary Artery Enlargement in Smokers

Background: Pulmonary artery enlargement (PAE) detected using chest computed tomography (CT) is associated with poor outcomes in chronic obstructive pulmonary disease (COPD). It is unknown whether nocturnal hypoxemia occurring in smokers, with or without COPD, obstructive sleep apnoea (OSA) or their overlap, may be associated with PAE assessed by chest CT. Methods: We analysed data from two prospective cohort studies that enrolled 284 smokers in lung cancer screening programs and completing baseline home sleep studies and chest CT scans. Main pulmonary artery diameter (PAD) and the ratio of the PAD to that of the aorta (PA:Ao ratio) were measured. PAE was defined as a PAD ≥ 29 mm in men and ≥27 mm in women or as a PA:Ao ratio > 0.9. We evaluated the association of PAE with baseline characteristics using multivariate logistic models. Results: PAE prevalence was 27% as defined by PAD measurements and 11.6% by the PA:Ao ratio. A body mass index ≥ 30 kg/m² (OR 2.01; 95%CI 1.06–3.78), lower % predicted of forced expiratory volume in one second (FEV₁) (OR 1.03; 95%CI 1.02–1.05) and higher % of sleep time with O₂ saturation < 90% (T90) (OR 1.02; 95%CI 1.00–1.03), were associated with PAE as determined by PAD. However, only T90 remained significantly associated with PAE as defined by the PA:Ao ratio (OR 1.02; 95%CI 1.01–1.03). In the subset group without OSA, only T90 remains associated with PAE, whether defined by PAD measurement (OR 1.02; 95%CI 1.01–1.03) or PA:Ao ratio (OR 1.04; 95%CI 1.01–1.07). Conclusions: In smokers with or without COPD, nocturnal hypoxemia was associated with PAE independently of OSA coexistence.

Is lung resection appropriate for late octogenarians? Surgical outcomes of patients aged ≥ 80 years with lung cancer

PURPOSE

This study aimed to determine the outcomes and prognostic factors associated with octogenarians who underwent pulmonary resection for lung cancer.

METHODS/PATIENTS

From 2009 to 2018, 76 octogenarians underwent pulmonary surgery for lung cancer at the Kanazawa Medical University, Japan. They were divided into two groups (early and late octogenarians), and their clinicopathological characteristics and outcomes were investigated. Overall survival rates and recurrence-free survival rates were determined using Kaplan-Meier curves. Univariate and multivariate analyses were performed to identify prognostic factors.

RESULTS

Limited surgery was performed more often in the late octogenarian group; however, most perioperative factors were not significantly different between the two groups. The 3-year overall survival and recurrence-free survival rates were 61.2% and 52.8%, respectively. The median observation period was 37.5 (8.9-112.3) months postoperatively. Kaplan-Meier curves showed that age ≥ 85 years (late octogenarian), smoking history, and squamous cell carcinoma on histology were associated with worse survival rates. Multivariate analysis identified age ≥ 85 years (late octogenarian) (p = 0.011) and cigarette smoking (p = 0.025) as unfavorable prognostic factors for overall survival and recurrence-free survival, respectively.

CONCLUSIONS

Most octogenarians with an indication for surgery can tolerate pulmonary surgery. However, owing to the limitations of this retrospective, single-center study, future studies involving multiple-institutions are required to confirm our findings.

CT Imaging and Comorbidities in COPD: Beyond Lung Cancer Screening

Comorbidities significantly contribute to morbidity, mortality, and health-care costs in individuals with COPD. Comorbidity prevalence does not always correlate with lung disease severity, and the elevated risk of certain comorbidities is often independent of shared risk factors such as tobacco burden. Although COPD management guidelines recognize the importance of identifying and treating comorbidities as part of the comprehensive management of COPD patients, little guidance is provided regarding best screening practices. Whereas universal comorbidity screening in COPD patients is likely not cost-effective, targeted early screening and treatment in those at highest risk may have a significant impact on COPD outcomes. Recent studies suggest that certain radiographic features on thoracic imaging may serve as surrogate markers of comorbidity in patients with COPD. This review evaluates these studies in the context of the growing availability of chest CT scans in the lung cancer screening era and discusses how chest CT imaging can be leveraged to identify those COPD patients at highest risk for comorbid disease.

Computed tomography appearances of the lung parenchyma in pulmonary hypertension

Computed tomography (CT) is a valuable tool in the workup of patients under investigation for pulmonary hypertension (PH) and may be the first test to suggest the diagnosis. CT parenchymal lung changes can help to differentiate the aetiology of PH. CT can demonstrate interstitial lung disease, emphysema associated with chronic obstructive pulmonary disease, features of left heart failure (including interstitial oedema), and changes secondary to miscellaneous conditions such as sarcoidosis. CT also demonstrates parenchymal changes secondary to chronic thromboembolic disease and venous diseases such as pulmonary venous occlusive disease (PVOD) and pulmonary capillary haemangiomatosis (PCH). It is important for the radiologist to be aware of the various manifestations of PH in the lung, to help facilitate an accurate and timely diagnosis. This pictorial review illustrates the parenchymal lung changes that can be seen in the various conditions causing PH.

Association of plain computed tomography-determined pulmonary artery-to-aorta ratio with clinical severity of coronavirus disease 2019

Coronavirus disease (COVID-19) is associated with pulmonary hypertension due to pulmonary embolism, which affects subsequent outcomes. However, definitive diagnosis of pulmonary hypertension is difficult because of the risk of spreading the infection. Here, we assess the utility of plane computed tomography in noninvasively predicting the clinical severity of COVID-19.

CT-Derived Pulmonary Artery Diameters to Preselect for Echocardiography in COPD Patients Eligible for Bronchoscopic Treatments

BACKGROUND

Currently, patients with COPD who are evaluated for bronchoscopic treatments are routinely screened for pulmonary hypertension (PH) and systolic left ventricle dysfunction by echocardiography.

OBJECTIVES

We evaluated the prevalence of PH and systolic left ventricle dysfunction in this patient group and investigated if the previously proposed CT-derived pulmonary artery to aorta (PA:A) ratio >1 and PA diameter measurements can be used as alternative screening tools for PH.

METHODS

Two hundred fifty-five patients were included in this retrospective analysis (FEV1 25%pred, RV 237%pred). All patients received transthoracic echocardiography and chest CT scans on which diameters of the aorta and pulmonary artery were measured at the bifurcation and proximal to the bifurcation.

RESULTS

Following echocardiography, 3 patients (1.2%) had PH and 1 (0.4%) had systolic left ventricle dysfunction. Using a PA:A ratio >1, only 10.3% of the patients with a right ventricular systolic pressure (RVSP) ≥35 mm Hg were detected and none of the patients with an RVSP >50 mm Hg were detected. Patients with an RVSP ≥35 mm Hg had significantly higher PA diameters (29.5 vs. 27.5 mm; p = 0.02) but no significantly different PA:A ratios. All patients with an RVSP >50 mm Hg had PA diameters >30 mm.

CONCLUSIONS

The prevalence of PH and systolic left ventricle dysfunction is low in this preselected cohort of patients with severe COPD. In this population, a PA:A ratio >1 is not a useful cardiac screening tool for PH. A PA diameter >30 mm could substitute for routinely performed echocardiography in the screening for PH in this patient group.

Disproportionally Impaired Diffusion Capacity Relative to Airflow Limitation in COPD

Forced expiratory volume in 1 s (FEV₁) is a standard physiological index of chronic obstructive pulmonary disease (COPD), but reflects emphysema and vascular abnormalities less sensitively than diffusion capacity for carbon monoxide (D_LCO). This study tested whether a disproportionally impaired D_LCO relative to FEV₁ (FEV₁ z-score>-3 and D_LCO z-score≤-3) is a common functional COPD phenotype associated with distinct clinical and structural features and the prognosis of two cohorts. The cross-sectional analyses of the Korea COPD Subgroup Study (KOCOSS) cohort (multicenter study in Korea) included 743 males with COPD whose D_LCO was available. The cross-sectional and longitudinal analyses of the Kyoto University Cohort (single-center study in Japan) included 195 males with COPD who were prospectively followed for 10 years. A disproportionally impaired D_LCO relative to FEV₁ was observed in 29% and 31% of patients in the KOCOSS and Kyoto University cohorts, respectively. In the multivariable analysis, the disproportionally impaired D_LCO was associated with worse symptoms, shorter 6-minute walking distance, paraseptal and centrilobular emphysema on computed tomography, and reduced arterial oxygen and carbon dioxide pressures compared to the reference (FEV₁ z-score>-3 and D_LCO z-score>-3). In the multivariable Cox proportional hazard model, a higher long-term mortality was observed in the disproportionally impaired D_LCO group than in the reference group (hazard ratio [95% confidence interval] = 3.09 [1.52-6.29]) and similar to the D_LCO z-score≤-3 and FEV₁ z-score≤-3 group. The disproportionally impaired D_LCO relative to FEV₁ is common and associated with increased symptoms, emphysema, arterial blood gas abnormalities, and increased long-term mortality in patients with COPD.

Computerized Chest Imaging in the Diagnosis and Assessment of the Patient with Chronic Obstructive Pulmonary Disease

Computerized tomography in chronic obstructive pulmonary disease (COPD) has been the subject of intense interest in the research and clinical community. Methods have been developed to objectively detect and quantify processes affecting the lung parenchyma, airways and vasculature, as well as extrapulmonary manifestations of the noxious effects of chronic inhalational exposures, such as tobacco smoke. This article provides a brief overview of image-based advances in COPD research and then discusses how these advances have translated to clinical care, finishing with a brief description of a path forward for the convergence of research and care at the bedside.

Multimorbidity in Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a complex disease manifested primarily as airflow limitation that is partially reversible as confirmed by spirometry. COPD patients frequently develop systemic manifestations, such as skeletal muscle wasting and cachexia. COPD patients often develop other comorbid diseases, such as ischemic heart disease, heart failure, osteoporosis, anemia, lung cancer, and depression. Comorbidities complicate management of COPD and need to be evaluated because detection and treatment have important consequences. Novel approaches aimed at integrating the multiple morbidities seen in COPD and other chronic diseases will provide new avenues of research and allow developing more comprehensive and effective therapeutic approaches.

Co-Morbidity Patterns Identified Using Latent Class Analysis of Medications Predict All-Cause Mortality Independent of Other Known Risk Factors: The COPDGene® Study

PURPOSE

Medication patterns include all medications in an individual's clinical profile. We aimed to identify chronic co-morbidity treatment patterns through medication use among COPDGene participants and determine whether these patterns were associated with mortality, acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and quality of life.

MATERIALS AND METHODS

Participants analyzed here completed Phase 1 (P1) and/or Phase 2 (P2) of COPDGene. Latent class analysis (LCA) was used to identify medication patterns and assign individuals into unobserved LCA classes. Mortality, AECOPD, and the St. George's Respiratory Questionnaire (SGRQ) health status were compared in different LCA classes through survival analysis, logistic regression, and Kruskal-Wallis test, respectively.

RESULTS

LCA identified 8 medication patterns from 32 classes of chronic comorbid medications. A total of 8110 out of 10,127 participants with complete covariate information were included. Survival analysis adjusted for covariates showed, compared to a low medication use class, mortality was highest in participants with hypertension+diabetes+statin+antiplatelet medication group. Participants in hypertension+SSRI+statin medication group had the highest odds of AECOPD and the highest SGRQ score at both P1 and P2.

CONCLUSION

Medication pattern can serve as a good indicator of an individual's comorbidities profile and improves models predicting clinical outcomes.

Advances in Chronic Obstructive Pulmonary Disease Imaging

Chest computed tomography (CT) imaging is a useful tool that provides in vivo information regarding lung structure. Imaging has contributed to a better understanding of COPD, allowing for the detection of early structural changes and the quantification of extra-pulmonary structures. Novel CT imaging techniques have provided insight into the progression of the main COPD subtypes, such as emphysema and small airway disease. This article serves as a review of new information relevant to COPD imaging. CT abnormalities, such as emphysema and loss of airways, are present even in smokers who do not meet the criteria for COPD and in those with mild-to-moderate disease. Subjects with mild-to-moderate COPD, with the highest loss of airways, also experience the highest decline in lung function. Extra-pulmonary manifestations of COPD, such as right ventricle enlargement and low muscle mass measured on CT, are associated with increased risk for all-cause mortality. CT longitudinal data has also given insight into the progression of COPD. Mechanically affected areas of lung parenchyma adjacent to emphysematous areas are associated with a greater decline in FEV₁. Subjects with the greatest percentage of small airway disease, as measured on matched inspiratory-expiratory CT scan, also present with the greatest decline in lung function.

A perspective for chronic obstructive pulmonary disease (COPD) management: six key clinical questions to improve disease treatment

INTRODUCTION

In 2011, the GOLD recommendations for the treatment of Chronic Obstructive Pulmonary Disease (COPD) introduced new clinical elements to classify the severity of the disease and to guide pharmacological choice. For the first time in the GOLD documents, treatment decision was no longer guided only by pulmonary function, but by a more complex combination of pulmonary function and clinical aspects. The recent versions of the GOLD recommendations introduce new aspects for the clinicians and pose new question for the management of the disease. In addition, inflammatory biomarkers and blood eosinophil levels, have been considered to guide treatment selection.

AREA COVERED

The evolution of disease management proposed by the GOLD document opens several areas of debate. A series of roundtable discussions among respiratory physicians took place in Italy to address key clinical questions. Particularly, the role of lung function and the use of biomarkers, the adherence to international guidelines and the possibility to personalize the pharmacological approach in COPD patients have been discussed, summarized and analyzed.

EXPERT OPINION

The authors believe that the development of a precision medicine approach tailoring the specific treatment for each patient is the goal of COPD management and may be achieved by considering the phenotypic classification of COPD patients.

Update on noninvasive imaging of right ventricle dysfunction in pulmonary hypertension

Pulmonary hypertension (PH) is a progressive disease affecting patients across the life span. The pathophysiology primarily involves the pulmonary vasculature and right ventricle (RV), but eventually affects the left ventricular (LV) function as well. Safe, accurate imaging modalities are critical for diagnosis, serial monitoring, and tailored therapy. While cardiac catheterization remains the conventional modality for establishing diagnosis and serial monitoring, noninvasive imaging has gained considerable momentum in providing accurate assessment of the entire RV-pulmonary axis. In this state-of-the-art review, we will discuss the most recent developments in echocardiography, magnetic resonance imaging, and computed tomography in PH evaluation from pediatric to adult population.

A Risk Prediction Model for Mortality Among Smokers in the COPDGene® Study

BACKGROUND

Risk factor identification is a proven strategy in advancing treatments and preventive therapy for many chronic conditions. Quantifying the impact of those risk factors on health outcomes can consolidate and focus efforts on individuals with specific high-risk profiles. Using multiple risk factors and longitudinal outcomes in 2 independent cohorts, we developed and validated a risk score model to predict mortality in current and former cigarette smokers.

METHODS

We obtained extensive data on current and former smokers from the COPD Genetic Epidemiology (COPDGene®) study at enrollment. Based on physician input and model goodness-of-fit measures, a subset of variables was selected to fit final Weibull survival models separately for men and women. Coefficients and predictors were translated into a point system, allowing for easy computation of mortality risk scores and probabilities. We then used the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS) cohort for external validation of our model.

RESULTS

Of 9867 COPDGene participants with standard baseline data, 17.6% died over 10 years of follow-up, and 9074 of these participants had the full set of baseline predictors (standard plus 6-minute walk distance and computed tomography variables) available for full model fits. The average age of participants in the cohort was 60 for both men and women, and the average predicted 10-year mortality risk was 18% for women and 25% for men. Model time-integrated area under the receiver operating characteristic curve statistics demonstrated good predictive model accuracy (0.797 average), validated in the external cohort (0.756 average). Risk of mortality was impacted most by 6-minute walk distance, forced expiratory volume in 1 second and age, for both men and women.

CONCLUSIONS

Current and former smokers exhibited a wide range of mortality risk over a 10- year period. Our models can identify higher risk individuals who can be targeted for interventions to reduce risk of mortality, for participants with or without chronic obstructive pulmonary disease (COPD) using current Global initiative for obstructive Lung Disease (GOLD) criteria.

Nivolumab increases pulmonary artery pressure in patients treated for non-small cell lung cancer

PURPOSE

The widespread use of Nivolumab results in an increasing number of side effects and adverse events. Herein, we evaluated the impact of Nivolumab on crude and normalized pulmonary artery diameter (PAD).

METHODS

We analyzed clinical, morphometric, pathological and radiological data of lung cancer patients treated by Nivolumab in an 18-month period. Blinded radiological evaluation was performed, by three observers measuring axial PAD and Aorta diameter (AoD) in secondarily matched pre- and post-Nivolumab CT-scans. Correlation between ΔPAD and clinicopathological data was investigated.

RESULTS

59 patients receiving Nivolumab for treatment of advanced lung carcinoma were identified. Pre-and post-Nivolumab comparison of CT-scan measures revealed that mean PAD was 26.3 ± 2.8 mm versus 28.0 ± 3.0 mm (p < 0.001), and mean PAD/AoD ratio was 0.82 ± 0.09 versus 0.87 ± 0.11 (p <  0.001), respectively. Median ΔPAD was 0.05 [0.01-0.122] was significantly higher in hypometabolic patients exhibiting low Rest Energy Expenditure (p = 0.03). Patients exhibiting ΔPAD > 1% had significantly lower serum albumin level (p = 0.03), and higher nutritional risk (p = 0.02), compared to others. Unlike Nivolumab therapy, there was no increase of PAD after chemotherapy in the same cohort of patients with available scans (n = 45, 25.9 ± 2.9 mm pre-chemotherapy versus 25.7 ± 2.4 mm post-chemotherapy, p = 0.51). Anti-PD-1 treatment was associated with immune-related adverse events in 11 (18.6%) cases including 2 cases of life-threatening acute pulmonary hypertension, both exhibiting post-treatment PAD/AoD ratio > 1.

CONCLUSION

Nivolumab is associated to PAD enlargement, a potential marker of pulmonary hypertension, sometimes leading to lethal adverse events. Careful CT-scan and echocardiographic evaluation of PAD should be part of the therapeutic work-up of patients receiving Nivolumab, especially those suffering cancer-associated malnutrition.

Variability and Standardization of Quantitative Imaging: Monoparametric to Multiparametric Quantification, Radiomics, and Artificial Intelligence

Radiological images have been assessed qualitatively in most clinical settings by the expert eyes of radiologists and other clinicians. On the other hand, quantification of radiological images has the potential to detect early disease that may be difficult to detect with human eyes, complement or replace biopsy, and provide clear differentiation of disease stage. Further, objective assessment by quantification is a prerequisite of personalized/precision medicine. This review article aims to summarize and discuss how the variability of quantitative values derived from radiological images are induced by a number of factors and how these variabilities are mitigated and standardization of the quantitative values are achieved. We discuss the variabilities of specific biomarkers derived from magnetic resonance imaging and computed tomography, and focus on diffusion-weighted imaging, relaxometry, lung density evaluation, and computer-aided computed tomography volumetry. We also review the sources of variability and current efforts of standardization of the rapidly evolving techniques, which include radiomics and artificial intelligence.

Machine Learning and Prediction of All-Cause Mortality in COPD

BACKGROUND

COPD is a leading cause of mortality.

RESEARCH QUESTION

We hypothesized that applying machine learning to clinical and quantitative CT imaging features would improve mortality prediction in COPD.

STUDY DESIGN AND METHODS

We selected 30 clinical, spirometric, and imaging features as inputs for a random survival forest. We used top features in a Cox regression to create a machine learning mortality prediction (MLMP) in COPD model and also assessed the performance of other statistical and machine learning models. We trained the models in subjects with moderate to severe COPD from a subset of subjects in Genetic Epidemiology of COPD (COPDGene) and tested prediction performance in the remainder of individuals with moderate to severe COPD in COPDGene and Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE). We compared our model with the BMI, airflow obstruction, dyspnea, exercise capacity (BODE) index; BODE modifications; and the age, dyspnea, and airflow obstruction index.

RESULTS

We included 2,632 participants from COPDGene and 1,268 participants from ECLIPSE. The top predictors of mortality were 6-min walk distance, FEV1 % predicted, and age. The top imaging predictor was pulmonary artery-to-aorta ratio. The MLMP-COPD model resulted in a C index ≥ 0.7 in both COPDGene and ECLIPSE (6.4- and 7.2-year median follow-ups, respectively), significantly better than all tested mortality indexes (P < .05). The MLMP-COPD model had fewer predictors but similar performance to that of other models. The group with the highest BODE scores (7-10) had 64% mortality, whereas the highest mortality group defined by the MLMP-COPD model had 77% mortality (P = .012).

INTERPRETATION

An MLMP-COPD model outperformed four existing models for predicting all-cause mortality across two COPD cohorts. Performance of machine learning was similar to that of traditional statistical methods. The model is available online at: https://cdnm.shinyapps.io/cgmortalityapp/.

Association Between Systemic and Pulmonary Vascular Dysfunction in COPD

Introduction

In chronic obstructive pulmonary disease (COPD), endothelial dysfunction and stiffness of systemic arteries may contribute to increased cardiovascular risk. Pulmonary vascular disease (PVD) is frequent in COPD. The association between PVD and systemic vascular dysfunction has not been thoroughly evaluated in COPD.

Methods

A total of 108 subjects were allocated into four groups (non-smoking controls, smoking controls, COPD without PVD and COPD with PVD). In systemic arteries, endothelial dysfunction was assessed by flow-mediated dilation (FMD) and arterial stiffness by pulse wave analysis (PWA) and pulse wave velocity (PWV). PVD was defined by a mean pulmonary artery pressure (PAP) ≥25 mmHg at right heart catheterization or by a tricuspid regurgitation velocity >2.8 m/s at doppler echocardiography. Biomarkers of inflammation and endothelial damage were assessed in peripheral blood.

Results

FMD was lower in COPD patients, with or without PVD, compared to non-smoking controls; and in patients with COPD and PVD compared to smoking controls. PWV was higher in COPD with PVD patients compared to both non-smoking and smoking controls in a model adjusted by age and the Framingham score; PWV was also higher in patients with COPD and PVD compared to COPD without PVD patients in the non-adjusted analysis. FMD and PWV correlated significantly with forced expiratory volume in the first second (FEV₁), diffusing capacity for carbon monoxide (DL_CO) and systolic PAP. FMD and PWV were correlated in all subjects.

Discussion

We conclude that endothelial dysfunction of systemic arteries is common in COPD, irrespective if they have PVD or not. COPD patients with PVD show increased stiffness and greater impairment of endothelial function in systemic arteries. These findings suggest the association of vascular impairment in both pulmonary and systemic territories in a subset of COPD patients.

Thoracic Imaging at Exacerbation of Chronic Obstructive Pulmonary Disease: A Systematic Review

Exacerbations of chronic obstructive pulmonary disease (COPD) are currently diagnosed based on changes in respiratory symptoms. Characterizing the imaging manifestation of exacerbations could be useful for objective diagnosis of exacerbations in the clinic and clinical trials, as well as provide a mechanism for monitoring exacerbation treatment and recovery. In this systematic review, we employed a comprehensive search across three databases (Medline, EMBASE, Web of Science) to identify studies that performed imaging of the thorax at COPD exacerbation. We included 51 from a total of 5,047 articles which met all our inclusion criteria. We used an adapted version of the Modified Newcastle-Ottawa Quality Assessment Scale for cohort studies to assess the quality of the included studies. Conclusions were weighted towards higher-quality articles. We identified a total of 36 thoracic imaging features studied at exacerbation of COPD. Studies were generally heterogeneous in their measurements and focus. Nevertheless, considering studies which performed consecutive imaging at stable state and exacerbation, which scored highest for quality, we identified salient imaging biomarkers of exacerbations. An exacerbation is characterized by airway wall and airway calibre changes, hyperinflation, pulmonary vasoconstriction and imaging features suggestive of pulmonary arterial hypertension. Most information was gained from CT studies. We present the first ever composite imaging signature of COPD exacerbations. While imaging during an exacerbation is comparatively new and not comprehensively studied, it may uncover important insights into the acute pathophysiologic changes in the cardiorespiratory system during exacerbations of COPD, providing objective confirmation of events and a biomarker of recovery and treatment response.

Pulmonary artery to ascending aorta ratio by echocardiography: A strong predictor for presence and severity of pulmonary hypertension

BACKGROUND

The pulmonary artery (PA) to ascending aorta diameter ratio (PA:A) has been evaluated in numerous studies analyzing cardiac magnetic resonance (CMR) and computed tomography (CT) data. Previously, no transthoracic echocardiography (TTE) cutoffs have been published. We sought to evaluate (1) the feasibility to image the pulmonary trunk in a prospective cohort, and (2) the ability of PA:A derived by TTE to predict pulmonary hypertension (PH).

METHODS

We performed a post-hoc analysis of a prospectively recruited consecutive cohort of patients referred to our tertiary center cardiology department due to suspicion for PH. Invasive hemodynamic assessment and quasi-simultaneous TTE was performed in all participants.

RESULTS

A total of 84 patients were included in the analysis, median age was 70.5 years (IQR 58-75), 46 (55%) were female. The PA was significantly wider in the PH group (28mm vs. 22.5mm, p<0.001) with a resulting median PA:A of 0.84 vs. 0.66 (p<0.001). Both PA diameter (r = 0.524 and r = 0.44, both p<0.001) and PA:A (r = 0.652 and 0.697, both p<0.001) significantly correlated with mPAP and with PVR, respectively. Area under the curve for the detection of PH was 0.853 (95%CI 0.739-0.967, p<0.001).

CONCLUSION

The PA can be visualized in almost all echocardiographic exams, especially when it is dilated. A view showing the pulmonary trunk should be included in every routine TTE. An increased PA:A should raise suspicion for PH and prompt further evaluation and follow-up examinations of these patients.

Pulmonary vascular enlargement on thoracic CT for diagnosis and differential diagnosis of COVID-19: a systematic review and meta-analysis

Background

The 2019 coronavirus disease (COVID-19) has become a global pandemic. To date, although many studies have reported on the computed tomography (CT) manifestations of COVID-19, the vascular enlargement sign (VES) of COVID-19 has not been deeply examined, with the few available studies reporting an inconsistent prevalence. We thus performed a systematic review and meta-analysis based on the best available studies to estimate the prevalence and identify the underlying differential diagnostic value of VES.

Methods

We searched nine English and Chinese language databases up to April 23, 2020. Studies that evaluated CT features of COVID-19 patients and reported VES, with or without comparison with other pneumonia were included. The methodologic quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Meta-analyses with random effects models were performed to calculate the aggregate prevalence and pooled odds ratios (ORs) of VES. We also conducted meta-regression and subgroup analyses to analyze heterogeneity.

Results

VES findings from a total of 1969 patients were summarized and pooled across 22 studies. Our analysis demonstrated that the prevalence of VES among COVID-19 patients was 69.37% [95% confidence interval (CI): 57.40-79.20%]. Compared with non-COVID-19 patients, VES manifestation was more frequently observed in confirmed COVID-19 patients (OR =6.43, 95% CI: 3.39-12.22). Studies that explicitly defined distribution of VES in the lesion area demonstrated a significantly higher prevalence (P=0.03). Subgroup analyses also revealed a relatively higher VES rate in studies with a sample size larger than 50, but the difference was not statistically significant. No significant difference in VES rates was found between different countries (China/Italy), regions (Hubei/outside Hubei), average age groups (over/less than 50-year-old), or slice thicknesses of CT scan. Extensive heterogeneity was identified across most estimates (I²>80%). Some of the variations (R²=19.73%) could be explained by VES distribution, and sample size. No significant publication bias was seen (P=0.29).

Conclusions

VES on thoracic CT was found in almost two-thirds of COVID-19 patients, and was more prevalent compared with that of the non-COVID-19 patients, supporting a promising role for VES in identifying pneumonia caused by coronavirus.

Pulmonary artery enlargement on routine staging 18F-fluodeoxyglucose positron emission tomography/CT for lung and oesophageal cancer

OBJECTIVE

Pulmonary hypertension (PH) is an underdiagnosed condition associated with poor survival and increased post-operative mortality in lung cancer. CT-based parameters of pulmonary artery enlargement are strong predictors of PH. We used these parameters to investigate pulmonary artery enlargement in lung and oesophageal cancer.

METHODS

Consecutive patients with lung cancer (n = 100) or oesophageal cancer (n = 100) undergoing staging ¹⁸F-fluodeoxyglucose PET/CT were retrospectively identified. The transverse diameter of the main pulmonary artery (mPA) and ascending aorta, and the pulmonary artery-to-ascending aorta (PA:A) ratio were obtained. Abnormal values were defined following the Framingham Heart Study cohort.

RESULTS

Lung cancer patients had a significantly increased mPA diameter compared to the oesophageal cancer patients (males: 27.29 ± 0.39 vs. 25.88 ± 0.24 mm, females: 26.10 ± 0.28 vs. 24.45 ± 0.18 mm). Similarly, a significantly increased proportion of these patients had an abnormal mPA diameter (males: 35.1% vs 12.5%, females: 32.6% vs 10.7%). Lung cancer patients also had a significantly higher PA:A ratio (males: 0.83 ± 0.01 vs. 0.79 ± 0.008, females: 0.85 ± 0.01 vs. 0.79 ± 0.009), with a larger proportion having an abnormal PA:A ratio (males: 24.6% vs 11.1%, females: 27.9% vs 14.3%).

CONCLUSION

Simple measurements of mPA diameter and PA:A ratio reveal that lung cancer patients exhibit increased rates of pulmonary artery enlargement compared to oesophageal cancer patients.

ADVANCES IN KNOWLEDGE

This study demonstrates there is an increased prevalence of pulmonary enlargement in lung cancer, easily detected on routine staging scans, holding implications for further work-up and risk stratification.

Differences in routes of guiding catheters for left coronary artery according to access sites assessed by the combined angiography-computed tomography system

Differences in guiding catheters (GCs) manipulations and selections among different access sites are currently unclear. We examined the differences in the routes of GCs for the left coronary artery (LCA) among the right radial, left radial, and femoral approaches. We used a combined angiography-computed tomography (CT) system that enabled to perform CT scans during percutaneous coronary intervention (PCI). We enrolled 88 patients who underwent CT scans during LCA PCI or percutaneous transluminal septal myocardial ablation. To evaluate the route of GCs, we analyzed the positions of the catheter's contact point on the contralateral aortic wall to the LCA ostium, which were expressed by the angle formed by the vertical line and the diagonal line from the GC shaft to the center of the aorta. The procedures were performed via the right radial in 47 cases, left radial in 20, and femoral approach in 21. The positions of the catheter's contact point were significantly different depending on the approaches (interquartile range - 3.7 [- 14.3 to 7.8], - 46.5 [- 76.9 to - 9.3], and - 30.7 [- 39.4 to - 22.4] degrees, respectively; p < 0.001). Multivariate analysis demonstrated that access sites and LCA ostium locations had significant impacts on the positions of the catheter's contact point. The routes of LCA GCs were different among the right radial, left radial, and femoral approaches.

Normalized Pulmonary Artery Diameter Predicts Occurrence of Postpneumonectomy Respiratory Failure, ARDS, and Mortality

Hypothesizing that pulmonary artery diameter is a marker of subclinical pulmonary hypertension, we assessed its impact on postoperative outcome in patients requiring pneumonectomy. Morphometric, clinical, and laboratory data were retrospectively retrieved from files of 294 consecutive patients treated by pneumonectomy for malignancy (289 NSCLC). Pulmonary artery was measured at bifurcation level on CT scan and normalized by body surface area. Median normalized pulmonary artery diameter (cut-off for analyses) was 14 mm/m2. Postoperatively, 46 patients required re-do intubation and 30 had acute respiratory distress syndrome (ARDS). Multivariate analysis showed that Charlson Comorbidity Index >5 (p = 0.0009, OR 3.8 [1.76-8.22]), right side of pneumonectomy (p = 0.013, OR 2.37 [1.20-4.71]), and higher normalized pulmonary artery diameter (p = 0.029, OR 2.16 [1.08-4.33]) were independent predictors of re-do intubation, while Charlson Comorbidity Index >5 (p = 0.018, OR 2.55 [1.17-5.59]) and higher normalized pulmonary artery diameter (p = 0.028, OR = 2.52 [1.10-5.77]) were independently associated with occurrence of ARDS. Post-operative mortality was 8.5%. Higher normalized pulmonary artery diameter, (p = 0.026, OR 3.39[1.15-9.95]), right side of pneumonectomy (p = 0.0074, OR 4.11 [1.46-11.56]), and Charlson Comorbidity Index >5 (p = 0.0011, OR 5.56 [1.99-15.54]) were independent predictors of postoperative death. We conclude that pre-operative normalized pulmonary artery diameter predicts the risk of re-do intubation, ARDS and mortality in patients undergoing pneumonectomy for cancer.

Updated Perspectives on Pulmonary Hypertension in COPD

Pulmonary hypertension (PH) is a frequent and important complication of chronic obstructive pulmonary disease (COPD). It is associated with worse clinical courses with more frequent exacerbation episodes, shorter survival, and greater need of health resources. PH is usually of moderate severity and progresses slowly, without altering right ventricular function in the majority of cases. Nevertheless, a reduced subgroup of patients may present disproportionate PH, with pulmonary artery pressure (PAP) largely exceeding the severity of respiratory impairment. These patients may represent a group with an exaggerated vascular impairment (pulmonary vascular phenotype) to factors that induce PH in COPD or be patients in whom idiopathic pulmonary arterial hypertension (PAH) coexist. The present review addresses the current definition and classification of PH in COPD, the distinction among the different phenotypes of pulmonary vascular disease that might present in COPD patients, and the therapeutic approach to PH in COPD based on the available scientific evidence.

CT-derived pulmonary vascular metrics and clinical outcome in COVID-19 patients

To assess pulmonary vascular metrics on chest CT of COVID-19 patients, and their correlation with pneumonia extent (PnE) and outcome, we analyzed COVID-19 patients with an available previous chest CT, excluding those performed for cardiovascular disease. From February 21 to March 21, 2020, of 672 suspected COVID-19 patients from two centers who underwent CT, 45 RT-PCR-positives (28 males, median age 75, IQR 66-81 years) with previous CTs performed a median 36 months before (IQR 12-72 months) were included. We assessed PnE, pulmonary artery (PA) diameter, ascending aorta (Ao) diameter, and PA/Ao ratio. Most common presentations were fever and dyspnea (15/45) and fever alone (13/45). Outcome was available for 41/45 patients, 15/41 dead and 26/41 discharged. Ground-glass opacities (GGOs) alone were found in 29/45 patients, GGOs with consolidations in 15/45, consolidations alone in 1/45. All but one patient had bilateral pneumonia, 9/45 minimal, 22/45 mild, 9/45 moderate, and 5/45 severe PnE. PA diameter (median 31 mm, IQR 28-33 mm) was larger than before (26 mm, IQR 25-29 mm) (P<0.001), PA/Ao ratio (median 0.83, IQR 0.76-0.92) was higher than before (0.76, IQR 0.72-0.82) (P<0.001). Patients with adverse outcome (death) had higher PA diameter (P=0.001), compared to discharged ones. Only weak correlations were found between ΔPA or ΔPA/Ao and PnE (ρ≤0.453, P≤0.032), with 4/45 cases with moderate-severe PnE and minimal increase in PA metrics. In conclusion, enlarged PA diameter was associated to death in COVID-19 patients, a finding deserving further investigation as a potential driver of therapy decision-making.

Risk factors associated with pulmonary hemorrhage and hemoptysis following percutaneous CT-guided transthoracic lung core needle biopsy: a retrospective study of 1,090 cases

Background

Pulmonary hemorrhage and hemoptysis are the second-most common and potentially life-threatening complications after pneumothorax following percutaneous computed tomography-guided transthoracic lung biopsy (PCTLB). Preventing hemorrhagic complications after PCTLB requires an accurate estimation of risk factors. This study investigated the risk factors associated with pulmonary hemorrhage and hemoptysis following PCTLB, and whether the ratio of main pulmonary artery diameter (mPAD) to ascending aorta diameter (mPAD/AAD ratio) is a risk factor.

Methods

We retrospectively analyzed 1,090 cases of PCTLB obtained from 1,050 patients using a core needle. The risk factors for overall pulmonary hemorrhage, higher-grade pulmonary hemorrhage, and hemoptysis were evaluated by multivariate analysis of patient characteristics, computed tomography (CT) imaging data including pulmonary artery diameter (mPAD) to ascending aorta diameter (mPAD/AAD) ratio, technical variables related to the biopsy, and pathologic findings.

Results

Pulmonary hemorrhage occurred in 31.38% (342/1,090) of PCTLB cases, including lower-grade (24.4%, 266/1,090) and higher-grade hemorrhage (6.97%, 76/1,090). The incidence of hemoptysis was 3.03% (33/1,090). Multivariate analysis revealed significant associations between overall pulmonary hemorrhage and lesion location in the lower lobe, subsolid and smaller lesions, greater lesion depth, and lung metastases. For higher-grade pulmonary hemorrhage, an mPAD/AAD ratio >1, smaller lesions, greater lesion depth, emphysema, and lung metastases were risk factors. Risk factors for hemoptysis were history of hypertension and lower- and higher-grade pulmonary hemorrhage.

Conclusions

Pulmonary artery enlargement detected by CT (mPAD/AAD ratio >1) is independently associated with higher-grade pulmonary hemorrhage following PCTLB.

Pulmonary hypertension and obstructive sleep apnea

Nokes B, Raza H, Malhotra A. Pulmonary hypertension and obstructive sleep apnea. J Clin Sleep Med . 2020;16(4):649.

The association of silicosis severity with pectoralis major muscle and subcutaneous fat volumes and the pulmonary artery/aorta ratio evaluated by CT

PURPOSE

Silicosis is an incurable occupational disease that sometimes rapidly progresses with fatal outcomes. We aimed to evaluate the association between disease severity and the change in the pectoralis major muscle volume (PMV), subcutaneous fat volume (SFV), and the pulmonary artery/aorta (P/Ao) ratio in patients with silicosis using computed tomography (CT).

METHODS

The study included 41 male silicosis patients and 41 control group subjects with available chest CT images. Using dedicated software, we measured PMV and SFV from the axial CT images. We calculated the P/Ao ratio and obtained body mass index (BMI) and forced expiratory volume/forced vital capacity (FEV1/FVC) results from hospital records. We used the chest X-ray profusion score according to the International Labor Organization (ILO) classification to evaluate the severity of the silicosis.

RESULTS

The mean age was 33.5±4.4 and 34.7±4.7 years in the silicotic and control groups, respectively. The mean BMI, PMV, SFV, and P/Ao values significantly differed between the study and control groups (P = 0.0009, P < 0.0001, P < 0.0001, and P = 0.0029, respectively). According to the ILO classification, there were 12 silicosis patients in category 1, 13 in category 2, and 16 in category 3. A significant difference was found between disease categories in terms of PMV, SFV, P/Ao, BMI, and FEV1/FVC values (P = 0.0425, P = 0.0341, P = 0.0002, P = 0.0492, and P = 0.0004, respectively).

CONCLUSION

Disease severity had a stronger association with decreased PMV and SFV and increased P/Ao ratios than BMI in patients with silicosis caused by denim sandblasting. Thus, CT evaluation might be a useful indicator of disease severity.

Acute exacerbations of chronic obstructive pulmonary disease: in search of diagnostic biomarkers and treatable traits

Acute exacerbations of chronic obstructive pulmonary disease (COPD) are associated with a significant mortality, health and economic burden. Their diagnosis, assessment and management remain suboptimal and unchanged for decades. Recent clinical and translational studies revealed that the significant heterogeneity in mechanisms and outcomes of exacerbations could be resolved by grouping them etiologically. This is anticipated to lead to a better understanding of the biological processes that underlie each type of exacerbation and to allow the introduction of precision medicine interventions that could improve outcomes. This review summarises novel data on the diagnosis, phenotyping, targeted treatment and prevention of COPD exacerbations.

Genetic Advances in Chronic Obstructive Pulmonary Disease. Insights from COPDGene

Chronic obstructive pulmonary disease (COPD) is a common and progressive disease that is influenced by both genetic and environmental factors. For many years, knowledge of the genetic basis of COPD was limited to Mendelian syndromes, such as alpha-1 antitrypsin deficiency and cutis laxa, caused by rare genetic variants. Over the past decade, the proliferation of genome-wide association studies, the accessibility of whole-genome sequencing, and the development of novel methods for analyzing genetic variation data have led to a substantial increase in the understanding of genetic variants that play a role in COPD susceptibility and COPD-related phenotypes. COPDGene (Genetic Epidemiology of COPD), a multicenter, longitudinal study of over 10,000 current and former cigarette smokers, has been pivotal to these breakthroughs in understanding the genetic basis of COPD. To date, over 20 genetic loci have been convincingly associated with COPD affection status, with additional loci demonstrating association with COPD-related phenotypes such as emphysema, chronic bronchitis, and hypoxemia. In this review, we discuss the contributions of the COPDGene study to the discovery of these genetic associations as well as the ongoing genetic investigations of COPD subtypes, protein biomarkers, and post-genome-wide association study analysis.

Pulmonary hypertension in chronic obstructive pulmonary disease

Even mild pulmonary hypertension (PH) is associated with increased mortality and morbidity in patients with chronic obstructive pulmonary disease (COPD). However, the underlying mechanisms remain elusive; therefore, specific and efficient treatment options are not available. Therapeutic approaches tested in the clinical setting, including long-term oxygen administration and systemic vasodilators, gave disappointing results and might be only beneficial for specific subgroups of patients. Preclinical studies identified several therapeutic approaches for the treatment of PH in COPD. Further research should provide deeper insight into the complex pathophysiological mechanisms driving vascular alterations in COPD, especially as such vascular (molecular) alterations have been previously suggested to affect COPD development. This review summarizes the current understanding of the pathophysiology of PH in COPD and gives an overview of the available treatment options and recent advances in preclinical studies. LINKED ARTICLES: This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.1/issuetoc.

Understanding the impact of chronic obstructive pulmonary disease exacerbations on patient health and quality of life

Exacerbations of chronic obstructive pulmonary disease (COPD) represent a significant clinical problem, and are associated with decreased lung function, worsening quality of life and decreased physical activity levels, with even a single exacerbation having detrimental effects. The occurrence of COPD exacerbations can also have a considerable impact on healthcare costs and mortality rates, with over one-fifth of patients hospitalized for a COPD exacerbation for the first time dying within one year of discharge. This highlights the need for COPD exacerbations to be a major focus in clinical practice. Furthermore, the substantial effect that COPD exacerbations can have on patient mental health should not be underestimated. Despite their clinical importance, COPD exacerbations are poorly recognized and reported by patients, and improving patient understanding and reporting of exacerbations to ensure prompt treatment may minimize their deleterious effects. Renewed focus on improving current clinical practice with support from evidence-based guidelines is required. This also raises a challenge to payors, healthcare systems and government policies to do more to tackle the considerable outstanding burden of COPD exacerbations.

Increased main pulmonary artery diameter and main pulmonary artery to ascending aortic diameter ratio in smokers undergoing lung cancer screening

OBJECTIVES

Pulmonary hypertension (PH) is a progressive, potentially fatal disease, difficult to diagnose early due to non-specific nature of symptoms. PH is associated with increased morbidity and death in many respiratory and cardiac disorders, and with all-cause mortality, independent of age and cardiopulmonary disease. The main pulmonary artery diameter (MPA), and ratio of MPA to adjacent ascending aorta (AA), MPA:AA, on Chest CT are strong indicators of suspected PH. Our goal was to determine the prevalence of abnormally high values of these indicators of PH in asymptomatic low-dose CT (LDCT) screening participants at risk of lung cancer, and determine the associated risk factors.

METHODS

We reviewed consecutive baseline LDCT scans of 1949 smokers in an IRB-approved study. We measured the MPA and AA diameter and calculated MPA:AA ratio. We defined abnormally high values as being more than two standard deviations above the average (MPA ≥ 34 mm and MPA:AA ≥ 1.0). Regression analyses were used to identify risk factors and CT findings of participants associated with high values.

RESULTS

The prevalence of MPA ≥ 34 mm and MPA:AA ≥ 1.0 was 4.2% and 6.9%, respectively. Multivariable regression demonstrated that BMI was a significant risk factor, both for MPA ≥ 34 mm (OR = 1.07, p < 0.0001) and MPA:AA ≥ 1.0 (OR = 1.04, p = 0.003). Emphysema was significant in the univariate but not in the multivariate analysis.

CONCLUSIONS

We determined that the possible prevalence of PH as defined by abnormally high values of MPA and of MPA:AA was greater than previously described in the general population and that pulmonary consultation be recommended for these participants, in view of the significance of PH.

Pulmonary artery enlargement is associated with pulmonary hypertension and decreased survival in severe cystic fibrosis: A cohort study

BACKGROUND

Pulmonary artery (PA) enlargement, defined as pulmonary artery to ascending aorta diameter ratio (PA:A)>1 on computed tomography (CT), is a marker of pulmonary vascular disease in chronic lung diseases. PA enlargement is prevalent in cystic fibrosis (CF), but its relationship to hemodynamics and prognostic utility in severe CF are unknown. We hypothesized that the PA:A would have utility in identifying pulmonary hypertension (PH) in severe CF and that PA enlargement would be associated with reduced transplant-free survival.

METHODS

We conducted a retrospective study of adults with CF undergoing lung transplant evaluation at a single center between 2000 and 2015. CT, right heart catheterization (RHC), and clinical data were collected. The PA:A was measured from a single CT slice. We measured associations between PA:A and invasive hemodynamic parameters including PH defined as a mPAP ≥25mmHg using adjusted linear and logistic regression models. Kaplan-Meier and adjusted Cox regression models were used to measure associations between PA:A>1, RHC-defined PH, and transplant-free survival in severe CF.

RESULTS

We analyzed 78 adults with CF that had CT scans available for review, including 44 that also had RHC. RHC-defined PH defined as a mPAP ≥25mmHg was present in 36% of patients with CF undergoing transplant evaluation. The PA:A correlated with mPAP (r = 0.73; 95% CI 3.87-7.80; p<0.001) and PVR (r = 0.42, p = 0.005) and the PA:A>1 was an independent predictor of PH (aOR 4.50; 95% CI 1.05-19.2; p = 0.042). PA:A>1 was independently associated with increased hazards for death or transplant (aHR 2.69; 95% CI 1.41-5.14; P = 0.003). The presence of mPAP ≥25mmHg was independently associated with decreased survival in this cohort.

CONCLUSIONS

PA enlargement is associated with pulmonary hemodynamics and PH in severe CF. PA enlargement is an independent prognostic indicator of PH and decreased survival in this population.

Performance of pulmonary artery dimensions measured on high-resolution computed tomography scan for identifying pulmonary hypertension

Background

On high-resolution computed tomography (HRCT), pulmonary artery (PA) dimensions may hint at the presence of pulmonary hypertension. We aimed to determine how accurately various measures of the PA, as viewed on HRCT, predict right heart catheterisation (RHC)-confirmed pulmonary hypertension.

Methods

We retrospectively reviewed patients who had HRCT and RHC between 2010 and 2018. Analyses considered respiratory cycle, pulmonary hypertension diagnostic criteria, time between HRCT and RHC, and subgroup analysis in interstitial lung disease (ILD) and chronic obstructive pulmonary disease (COPD).

Results

Of 620 patients, 375 had pulmonary hypertension. For pulmonary hypertension (defined as mean PA pressure (mPAP) ≥25 mmHg) and from HRCT performed within 60 days of RHC, main PA diameter (MPAD) ≥29 mm had a sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 88%, 42%, 0.70 and 0.70, respectively, while ratio of the diameter of the PA to the diameter of the ascending aorta (PA:Ao) ≥1.0 showed 53%, 85%, 0.84 and 0.54, respectively. In general, results were similar when the interval between HRCT and RHC varied from 7 to 60 days and when measured on expiratory images. In ILD, the sensitivity of MPAD was higher; in COPD, the specificity of PA:Ao was higher. There was moderately positive correlation between mPAP and inspiratory MPAD, PA:Ao, right PA diameter (RPAD), left PA diameter (LPAD) and (RPAD+LPAD)/2 (r=0.48, 0.51, 0.34, 0.34 and 0.36, respectively), whereas there was weak negative correlation between mPAP and PA angle (r= -0.24).

Conclusions

Findings on HRCT may assist in the diagnosis of RHC-confirmed pulmonary hypertension. MPAD ≥29 mm had high sensitivity and PA:Ao ≥1.0 had high specificity. Compared with the entire cohort, MPAD had greater sensitivity in ILD and PA:Ao had higher specificity in COPD.

MicroRNA-143-5p modulates pulmonary artery smooth muscle cells functions in hypoxic pulmonary hypertension through targeting HIF-1α

This paper explores the potential mechanism of microRNA-143-5p regulation effects on pulmonary artery smooth muscle cells (PASMCs) functions in hypoxic pulmonary hypertension (HPH) via targeting HIF-1a, which may offer a new idea for HPH therapy. PASMCs were transfected with mimics control/miR-143-5p mimics or inhibitor control/miR-143-5p inhibitor. We used Western blotting and RT-qPCR to detect the protein and mRNA expressions, CCK-8 assay to detect cellular viability, Annexin V-FITC/PI staining and caspase- 3/cleaved caspase-3 protein to evaluate cellular apoptosis, transwell migration experiment for cellular migration measurement and Dual luciferase reporter gene assay to prove the target of miR-143-5p. Cells under hypoxic condition presented the decreased protein and mRNA expressions of α-smooth muscle actin (SM-α-actin), Myocardin, smooth muscle myosin heavy chain (SMMHC), and smooth muscle-22α (SM22α), Calponin1 and Hypoxia-inducible factor-1α(HIF-1α), the increased cell viability and miR-143-5p level; Overexpression of miR-143-5p obviously reduced vascular smooth muscle-specific contraction marker protein levels and cellular apoptosis, increased cellular migration of PASMCs with hypoxia stimulation; Low-expression of miR-143-5p caused the opposite changes, while co-transfected with Si HIF-1 α blocked the beneficial effects of miR-143-5p inhibition on PASMCs under hypoxia. MicroRNA-143-5p can promote the phenotype conversion, proliferation and migration of pulmonary artery smooth muscle cells under hypoxic condition through direct targeting of HIF-1α.

Serum bilirubin level is associated with exercise capacity and quality of life in chronic obstructive pulmonary disease

BACKGROUND

Bilirubin has antioxidant properties against chronic respiratory diseases. However, previous studies are limited by acquisition of serum bilirubin level at one time point and its analysis with clinical parameters. We evaluated the association of serum bilirubin levels with various clinical outcomes of chronic obstructive pulmonary disease (COPD) in Korean Obstructive Lung Disease (KOLD) cohort.

METHODS

We included 535 patients with COPD from the KOLD cohort. Serum bilirubin levels and various clinical parameters, such as lung function, 6-min walking (6 MW) distance, quality of life (QoL), and exacerbation, were evaluated annually; their association was analyzed using generalized estimating equations and the linear mixed model.

RESULTS

Among 535 patients, 345 (64.5%) and 190 (35.5%) were categorized into Global Initiative for Chronic Obstructive Lung Disease (GOLD) I-II and GOLD III-IV groups, respectively. 6 MW distance was positively associated with serum bilirubin levels, especially in the GOLD I-II group (estimated mean = 41.5). Among QoL indexes, the COPD assessment test score was negatively associated with serum bilirubin levels only in the GOLD I-II group (estimated mean = - 2.8). Higher serum bilirubin levels were independently associated with a higher number of acute exacerbation in the GOLD III-IV group (estimated mean = 0.45, P = 0.001). Multivariate analysis revealed that lung function and mortality were not associated with serum bilirubin levels.

CONCLUSIONS

Higher serum bilirubin levels were associated with a longer 6 MW distance and better QoL, especially in the GOLD I-II group, whereas they were related to a higher risk of acute exacerbation, especially in the GOLD III-IV group. Bilirubin levels may represent various conditions in COPD.