Predicting pulmonary hypertension with standard computed tomography pulmonary angiography

Area of Science:

• Radiology
• Cardiology
• Pulmonology

Background:

• Pulmonary hypertension (PH) diagnosis relies on imaging, with computed tomography pulmonary angiography (CTPA) commonly showing an increased pulmonary artery to ascending aorta diameter ratio (PA/AAAX).
• The diagnostic utility of PA/AAAX alone in predicting precapillary PH requires enhancement.

Purpose of the Study:

• To evaluate if combining PA/AAAX measurements with ventricular dimensions improves CTPA's predictive value for precapillary PH.
• To compare the efficacy of different CTPA measurement combinations in predicting precapillary PH.

Main Methods:

• Analysis of baseline CTPA scans from 51 treatment-naïve precapillary PH patients and 25 non-PH controls.
• Comparison of three predictive models: PA/AAAX alone (model 1), PA/AAAX with axial ventricular ratio (RV/LVAX) (model 2), and PA/AAAX with four-chamber ventricular ratio (RV/LV4CH) (model 3).
• Statistical comparison using multivariable binary logistic regression, Receiver Operating Characteristic (ROC) analyses, and Decision Curve Analyses (DCA).

Main Results:

• Models 2 and 3 demonstrated improved predictive value over model 1, as indicated by logistic regression (-2LL values) and significantly higher Area Under the Curve (AUC) in ROC analyses (p=0.011 and p=0.007).
• DCA revealed increased clinical benefit for models 2 and 3 compared to model 1, with comparable predictive performance between models 2 and 3.
• An optimal cut-off for RV/LV ratio predicting precapillary PH was identified as ≥1.20.

Conclusions:

• Combining ventricular measurements with PA/AAAX on CTPA enhances predictive accuracy for precapillary PH.
• CTPA findings of PA/AAAX ≥1 or RV/LVAX ≥1.20 warrant further diagnostic evaluation for precapillary PH.