Table 1

Radiographic metrics

Hypothesized predictors of PH

How measured


Main pulmonary artery diameter (PA)

Widest lumen at or near level of PA bifurcation *


Right pulmonary artery diameter (RPA)

Widest lumen caudal to ascending aorta


Left pulmonary artery diameter (LPA)

Widest lumen


Right descending pulmonary artery (RDPA)

Distance from lateral wall of right bronchus intermedius to lateral wall of RDPA (equivalent to the RDPA measurement on a chest x-ray)


True right descending pulmonary artery (true RDPA)

RDPA lumen diameter only *


True left descending pulmonary artery (true LDPA)

Lumen diameter distal to left upper lobe bronchus takeoff


Right ventricular free wall (RV wall)

Mid-ventricle *


Right ventricular lumen diameter (RV lumen)

Mid-ventricle *


Left ventricular free wall (LV wall)

Mid-ventricle *


Left ventricular lumen diameter (LV lumen)

Mid-ventricle *


IV septum bowing into LV

Yes or no


Left apical artery to corresponding bronchus ratio

Most apical bronchovascular pair


Hilar diameter (HD)

At level of right middle lobe bronchus takeoff


Hilar/Thoracic ratio

HD/Inner thoracic diameter (TD) measured at same level as HD


Landmarks used to standardize predictors of PH


Ascending aorta diameter (AA)

Widest diameter at the level of the PA measurement *


Descending aorta diameter (DA)

At same level as AA *


* Also see Figure 1

Chan et al. BMC Medical Imaging 2011 11:7   doi:10.1186/1471-2342-11-7

Open Data