CТ densitometry as an additional method in the diagnosis of pulmonary hypertension: a prospective study

INTRODUCTION: This article presents the results of application of CT densitometry in the computed tomography (CT) of the chest to diagnose various forms of pulmonary hypertension.

OBJECTIVES: To determine the diagnostic value of CT densitometry using comparative analysis of lung tissue density in patients with various forms of pulmonary hypertension.

MATERIALS AND METHODS: The study included 528 patients diagnosed with pulmonary hypertension by means of right heart catheterization (RHC) of the National Research Cardiac Surgery Center, Republic of Kazakhstan. All patients were divided into 4 groups according to the classification of pulmonary hypertension of the World Health Organization (ESC/ERS Guidelines) from 2015. The first group included 254 patients with pulmonary hypertension pulmonary hypertension due to left heart disease (PHLHD). The second group included 210 patients with pulmonary arterial hypertension (PAH). The third group included 49 patients with chronic thromboembolic pulmonary hypertension (CTEPH). The fourth group — 15 patients with pulmonary hypertension due to respiratory disease (PHDRD). The mean age of the patients was 52.15±16.75 years. Contrast-enhanced chest CT imaging performed with a 64-slice multislice computed tomography system (Somatom Definition AS, Siemens) with post-processing to assess the lung tissue densitometric parameters, analyse the diameters of the pulmonary trunk and its main branches. The CT examination was carried in accordance with an «Embolism» protocol with intravenous administration of a contrast agent according to indications. Statistics: analysis was conducted using the Statistica 10 software. To quantitatively compare the two groups nonparametric Mann-Whitney test and the Kruskal-Wallace test were applied. Mean value and standard deviation in the format of «M±S» were used for quantitative parameters. Correlation analysis was carried out using Spearman’s nonparametric rank correlation.

RESULTS: In patients with severe pulmonary hypertension a tendency for fibrotic changes was most clearly observed in cases of pulmonary hypertension due to left heart disease (–809.92±26.52), and emphysematous changes in the pulmonary arterial hypertension group (–843.27±43.88).

CONCLUSION: CT lung densitometry should be performed in all patients with suspected pulmonary hypertension as an additional method of examination.

1. Hoeper M.M., Humbet M., Souza R. et al. A global view of pulmonary hypertension // Lancet Respir. Med. 2016. Vol. 4, No. 4. P. 306–322. doi: 10.1016/S22132600(15)00543-3.

2. Gilbertson A. Pulmonary artery catheterization and wedge pressure measurement in the general intensive care unit // Survey of anesthesiology. 1975. Vol. 19, No. 3. P. 291. doi: 10.1093/bja/46.2.97.

3. Okajima Y., Ohno Y., Washko G. et al. Assessment of Pulmonary Hypertension: What CT and MRI Can Provide // Academic Radiology. 2011. Vol. 18, No. 4. P. 437–453. doi: 10.1016/j.acra.2011.01.003.

4. Muller N.L., Stapels C.A., Miller R.R. et al. «Density Mask»: an objective method to quantitate mphysema using computed tomography // Chest. 1998. Vol. 94. P. 782–787. doi: 10.1378/chest.94.4.782.

5. Uppaluri R., Mitsa T., Sonka M. et al. Quantification of pulmonary emphysema from lung computed tomography images // American Journal of Respiratory аnd Critical Care Medicine. 1997. Vol. 156, No. 1. P. 248–254. doi: 10.1164/ajrccm.156.1.9606093.

6. Bankier A.A., de Maertelaer V., Keyzer C. et al. CT of pulmonary emphysema: subjective assessment and objective quantification by densitometry and macroscopic morphometry; Detection of emphysema with computed tomography: correlation with pulmonary function tests and chest radiography) // Radiology. 1999. Vol. 211, No. 3. P. 851–858. doi: 10.1148/radiology.211.3.r99jn05851.

7. Lauge S., Mads N., Jens P. et al. Chronic obstructive pulmonary disease quantification using CT texture analysis and densitometry: Results from the Danish lung cancer screening trial // American Journal of Roengenology. 2020. Vol. 214. P. 1269–1279. doi: 10.2214/AJR.19.22300.

8. Marialuisa B., Dario B., Michele D., Performance of a new quantitative computed tomography index for interstitial lung disease assessment in systemic sclerosis // Scientific reports. 2019. Vol. 9, No. 1. 9468. doi: 10.1038/s41598-019-45990-7.

9. Cottin V., Brown K.K. Interstitial lung disease associated with systemic sclerosis (SSc-ILD) // Respir. Res. 2019. Vol. 20, No. 1. Р. 13. doi: 10.1186/s12931-0190980-7.

10. Van Royen F.S. et al. Automated CT quantification methods for the assessment of interstitial lung disease in collagen vascular diseases: A systematic review // Eur. J. Radiol. 2019. Vol. 112. P. 200–206. doi: 10.1016/j.ejrad.2019.01.024.

11. Simonneau G., Montani D., Celermajer D.S. et al. Haemodynamic definitions and updated clinical classification of pulmonary hypertension // Eur. Respir. J. 2019. Vol. 53, No. 1. Р. 1–13. doi: 10.1183/13993003.01913-2018.

12. Swetabh P., Arsh G., Vinod J. еt al. Evaluation of Pulmonary Hypertension in Stable Chronic Obstructive Pulmonary Disease Patients using Transthoracic Echocardiography // Biomedical and Biotechnology Research Journal (BBRJ). 2019. Vol. 3, No. 1. P. 53–56. doi: 10.4103/bbrj.bbrj_4_19.