Prognostic impact of the ratio of the main pulmonary artery to that of the aorta on chest computed tomography in patients with idiopathic pulmonary fibrosis

A composite score based on cardiovascular parameters can predict the mortality risk of patients with newly diagnosed interstitial lung disease: A prospective observational study

BACKGROUND

It is crucial to identify factors that can predict the risk of mortality in patients newly diagnosed with interstitial lung disease (ILD). This study sought to develop and assess a composite scoring system for mortality prediction among ILD patients based on cardiovascular parameters, which were previously reported as predictors of survival.

METHODS

We prospectively enrolled patients with newly diagnosed ILD and monitored their survival status for 24 months. Surviving and deceased patients were compared regarding their baseline characteristics including clinical, pulmonary, and cardiovascular parameters. A system of composite scores was established based on significant cardiovascular parameters and the Gender-Age-Physiology (GAP) score. Receiver operating characteristic curves were generated to identify their optimal cut-off values. Univariate as well as multiple multivariate regression models were built to investigate the mortality prediction of different individual and combined parameters.

RESULTS

Ninety-six patients newly diagnosed with ILD underwent cardiovascular evaluation. In univariate analysis, three cardiovascular parameters were identified as significant predictors of mortality risk in ILD patients, either individually or as a combination of composite scores: tricuspid regurgitation velocity > 3.1 m/s; N-terminal pro-B-type natriuretic peptide level > 300 pg/ml and computed tomography pulmonary artery/ascending aorta diameter ratio > 0.9. In multivariate analysis, a composite score of those parameters [hazard ratio (HR) = 2.37 (confidence interval [CI]:1.06-5.33); p = 0.037; Score 1] and GAP score [HR = 1.62 (CI: 1.11-2.36); p = 0.012] were the most significant predictors for mortality among ILD patients. Combination of Score 1 and GAP score (Score 2) can increase the accuracy of survival predictions (area under the curve 0.83; p < 0.001).

CONCLUSIONS

A composite score based on cardiovascular parameters and the GAP score can be used to predict the risk of mortality of patients with ILD. Such a score achieved better diagnostic accuracy than the GAP score alone. Nevertheless, further larger-scale randomized controlled trials are required for evaluation of the newly proposed score and confirmation of our results.

The association between pulmonary artery enlargement and mortality in an Emergency Department population undergoing computed tomography pulmonary angiography

Findings of an enlarged pulmonary artery diameter (PAd) and increased pulmonary artery to ascending aorta ratio (PA:AA) on contrast-enhanced computed tomography pulmonary angiography (CTPA) are associated with increased mortality in particular groups of patients with cardiopulmonary disease. However, the frequency and prognostic significance of these incidental findings has not been studied in unselected patients evaluated in the Emergency Department (ED). This study aims to determine the prevalence and associated prognosis of enlarged pulmonary artery measurements in an ED cohort. We measured PA and AA diameters on 990 CTPA studies performed in the ED. An enlarged PA diameter was defined as >27 mm in females and >29 mm in males, while an increased PA:AA was defined as >0.9. Poisson regression was performed to calculate prevalence ratios for relevant comorbidities, and multivariable Cox regression was performed to calculate hazard ratios (HR) for mortality of patients with enlarged pulmonary artery measurements. An enlarged PAd was observed in 27.9% of 990 patients and was more commonly observed in older patients and in patients with obesity or heart failure. Conversely, PA:AA was increased in 34.2% of subjects, and was more common in younger patients and those with peripheral vascular disease or obesity. After controlling for age, sex, and comorbidities, both enlarged PAd (HR 1.29, 95% CI 1.00-1.68, p = 0.05) and PA:AA (HR 1.70, 95% CI 1.31-2.22 p < 0.01) were independently associated with mortality. In sum, enlarged PAd and increased PA:AA are common in patients undergoing CTPAs in the ED setting and both are independently associated with mortality.

Preoperative Pulmonary Artery-to-Aorta Diameter Ratio as a Predictor of Postoperative Severe Right Ventricular Failure and 1-Year Mortality After Left Ventricular Assist Device Implantation

OBJECTIVES

To evaluate the association of pulmonary artery diameter and pulmonary artery- to-aorta diameter ratio (PA/Ao) with right ventricular failure and mortality within 1 year after left ventricular assist device implantation.

DESIGN

This was a retrospective observational study between March 2013 and July 2019.

SETTING

The study was conducted at a single, quaternary-care academic center.

PARTICIPANTS

Adults (≥18 years old) receiving a durable left ventricular assist device (LVAD). Inclusion if (1) a chest computed tomography scan was performed within 30 days before the LVAD and (2) a right and left heart catheterization was completed within 30 days before the LVAD.

INTERVENTIONS

A left ventricular assist device was used for intervention.

MEASUREMENTS AND MAIN RESULTS

A total of 176 patients were included in this study. Median PA diameter and PA/Ao ratio were significantly greater in the severe right ventricular failure (RVF) group (p = 0.001, p < 0.001, respectively). Receiver operating characteristic analysis revealed PA/Ao and RVF as predictors for mortality (area under the curve = 0.725 and 0.933, respectively). Logistic regression analysis-predicted probability gave a PA/Ao ratio cutoff point of 1.04 (p < 0.001). Survival probability was significantly worse in patients with a PA/Ao ratio ≥1.04 (p = 0.005).

CONCLUSIONS

The PA/Ao ratio is an easily measurable noninvasive indicator that can predict RVF and 1-year mortality after LVAD implantation.

Association between pulmonary artery to aorta diameter ratio with pulmonary hypertension and outcomes in diffuse cystic lung diseases

To investigate the importance of pulmonary vascular measurements on computed tomography (CT) in predicting pulmonary hypertension (PH) and worse outcomes in diffuse cystic lung diseases (DCLDs).We conducted a cross-sectional study of patients with DCLDs. Patients underwent pulmonary function tests, a six-minute walk test (6MWT), chest CT, transthoracic echocardiography, and right heart catheterization. Pulmonary artery (PA) diameter and PA-ascending aorta ratio (PA-Ao ratio) were obtained from CT. Mean pulmonary artery pressure (mPAP) from right heart catheterization was correlated with tomographic, functional, and echocardiographic variables. The association between the PA-Ao ratio with outcomes was determined by Kaplan-Meier curves.Thirty-four patients were included (18 with pulmonary Langerhans cell histiocytosis and 16 with lymphangioleiomyomatosis, mean age 46 ± 9 years). Forced expiratory volume in the first second and lung diffusing capacity for carbon monoxide were 47 ± 20% and 38 ± 21% predicted, respectively. PA diameter and PA-Ao ratio were 29 ± 6 mm and 0.95 ± 0.24, respectively. PA-Ao ratio > 1 occurred in 38.2% of patients. PA-Ao ratio was a good predictor of PH. mPAP correlated best with PA-Ao ratio, PA diameter, oxygen desaturation during six-minute walk test, and echocardiographic variables. Patients with PA-Ao ratio > 1 had greater mPAP, and a higher risk of death or lung transplantation (log-rank, P < .001) than those with PA-Ao ratio ≤ 1.The PA-Ao ratio measured on CT scan has a potential role as a non-invasive tool to predict the presence of PH and as a prognostic parameter in patients with DCLDs.

Diagnostic approach of fibrosing interstitial lung diseases of unknown origin

Interstitial lung diseases encompass a broad range of numerous individual conditions, some of them characterized histologically by fibrosis, especially idiopathic pulmonary fibrosis, nonspecific interstitial pneumonia, chronic hypersensitivity pneumonia, interstitial lung disease associated with connective tissue diseases, and unclassifiable interstitial lung disease. The diagnostic approach relies mainly on the clinical evaluation, especially assessment of the patient's demographics, history, smoking habits, occupational or domestic exposures, use of drugs, and on interpretation of high-quality HRCT of the chest. Imaging is key to the initial diagnostic approach, and often can confirm a definite diagnosis, particularly a diagnosis of idiopathic pulmonary fibrosis when showing a pattern of usual interstitial pneumonia in the appropriate context. In other cases, chest HRCT may orientate toward an alternative diagnosis and appropriate investigations to confirm the suspected diagnosis. Autoimmune serology helps diagnosing connective disease. Indications for bronchoalveolar lavage and for lung biopsy progressively become more restrictive, with better considerations for their discriminate value, of the potential risk associated with the procedure, and of the anticipated impact on management. Innovative techniques and genetics are beginning to contribute to diagnosing interstitial lung disease and to be implemented routinely in the clinic. Multidisciplinary discussion, enabling interaction between pulmonologists, chest radiologists, pathologists and often other healthcare providers, allows integration of all information available. It increases the accuracy of diagnosis and prognosis prediction, proposes a first-choice diagnosis, may suggest additional investigations, and often informs the management. The concept of working diagnosis, which can be revised upon additional information being made available especially longitudinal disease behaviour, helps dealing with diagnostic uncertainty inherent to interstitial lung diseases and facilitates management decisions. Above all, the clinical approach and how thoroughly the patient's history and possible exposures are assessed determine the possibility of an accurate diagnosis.

Comparing effectiveness of prognostic tests in idiopathic pulmonary fibrosis

Introduction: Idiopathic pulmonary fibrosis (IPF) is a debilitating and progressive fibrotic interstitial lung disease often resulting in death over several years. Prediction of disease course or survival remains of keen interest for clinicians and patients though a commonly used test or tool remain elusive. Areas covered: We undertook a comprehensive review of the published literature highlighting prognostic indicators and predictors of survival in IPF. Baseline and longitudinal clinical, functional, histopathologic, and radiologic findings have been extensively studied as prognostic predictors, both individually and in composite models. Recent approaches include automated quantifiable radiologic scoring, circulating biomarkers, and genetic polymorphisms or abnormalities. This review highlights individual and composite predictors and their relative utility in clinical practice and research studies. Expert opinion: There is a growing body of knowledge highlighting readily available individual and composite predictors of outcome, though none have come to the forefront for common clinical use. Recent advances include quantitative imaging analysis, circulating serologic markers, and genetic testing, which may be more standardized and less prone to lead-time bias or related complications and comorbidities.