Chest
Volume 160, Issue 6, December 2021, Pages 2220-2231
Journal home page for Chest

Pulmonary Vascular: Original Research
Quantification of Arterial and Venous Morphologic Markers in Pulmonary Arterial Hypertension Using CT Imaging

https://doi.org/10.1016/j.chest.2021.06.069Get rights and content
Under a Creative Commons license
open access

Background

Pulmonary hypertension is a heterogeneous disease, and a significant portion of patients at risk for it have CT imaging available. Advanced automated processing techniques could be leveraged for early detection, screening, and development of quantitative phenotypes. Pruning and vascular tortuosity have been previously described in pulmonary arterial hypertension (PAH), but the extent of these phenomena in arterial vs venous pulmonary vasculature and in exercise pulmonary hypertension (ePH) have not been described.

Research Question

What are the arterial and venous manifestations of pruning and vascular tortuosity using CT imaging in PAH, and do they also occur in ePH?

Study Design and Methods

A cohort of patients with PAH and ePH and control subjects with available CT angiograms were retrospectively identified to examine the differential arterial and venous presence of pruning and tortuosity in patients with precapillary pulmonary hypertension not confounded by lung or thromboembolic disease. The pulmonary vasculature was reconstructed, and an artificial intelligence method was used to separate arteries and veins and to compute arterial and venous vascular volumes and tortuosity.

Results

A total of 42 patients with PAH, 12 patients with ePH, and 37 control subjects were identified. There was relatively lower (median [interquartile range]) arterial small vessel volume in subjects with PAH (PAH 14.7 [11.7-16.5; P < .0001]) vs control subjects (16.9 [15.6-19.2]) and venous small vessel volume in subjects with PAH and ePH (PAH 8.0 [6.5-9.6; P < .0001]; ePH, 7.8 [7.5-11.4; P = .004]) vs control subjects (11.5 [10.6-12.2]). Higher large arterial volume, however, was only observed in the pulmonary arteries (PAH 17.1 [13.6-23.4; P < .0001] vs control subjects 11.4 [8.1-15.4]). Similarly, tortuosity was higher in the pulmonary arteries in the PAH group (PAH 3.5 [3.3-3.6; P = .0002] vs control 3.2 [3.2-3.3]).

Interpretation

Lower small distal pulmonary vascular volume, higher proximal arterial volume, and higher arterial tortuosity were observed in PAH. These can be quantified by using automated techniques from clinically acquired CT scans of patients with ePH and resting PAH.

Key Words

arterial
CT imaging
exercise pulmonary hypertension
pulmonary arterial hypertension
tortuosity
venous

Abbreviations

ePH
exercise pulmonary hypertension
PAH
pulmonary arterial hypertension

Cited by (0)

Drs Rahaghi and Nardelli are joint first authors.

Drs Raúl San José Estépar and Washko are joint senior authors.

FUNDING/SUPPORT: This study was supported in part by National Heart, Lung, and Blood Institute Grants [1K23HL136905, F. N. R; 5R01HL116473, Raúl San José Estépar and G. R. W.; 1R01HL149877, Raúl San José Estépar; and 5K08HL145118, S. Y. A.].