Data from: Contrast circulation time to assess right ventricular dysfunction in pulmonary embolism: a retrospective pilot study

Objective: To optimize enhancement of pulmonary arteries and facilitate
diagnosis of pulmonary embolism (PE), modern computed tomography
angiography (CTA) contains a contrast bolus tracking system. We explored
the diagnostic accuracy of the time-intensity curves given by this
automated system to identify right ventricular dysfunction (RVD) in acute
PE. Methods: 114 CTAs with a diagnosis of PE were reviewed. RVD was
defined as right-to-left ventricular diameter ratio of 1 or greater. Four
parameters on time-intensity curves were identified. Parameters between
CTAs with and those without RVD were compared with the Wilcoxon rank-sum
test. The ability of the four parameters to discriminate patients with RVD
was explored by compiling the area under the operating curves (AUC).
Results: The time needed by the contrast media to reach the pulmonary
artery [8 seconds (IQR: 7-9) versus 7 seconds (IQR: 6-8), p<0.01],
the time needed to reach 40 Hounsfield units (HU) [11 seconds (IQR:
8.5-14) versus 9.5 seconds (IQR: 8-10.5), p<0.01], and the contrast
intensity reached after 10 seconds [19 HU (IQR: 4-67) versus 53 HU (IQR:
32-80), p<0.05] were all statistically different between CTA with
and CTA without RVD. Those three parameters changed gradually across
severity categories of RVD (p<0.05 for trend). Their AUC to
identify RVD ranged from 0.63 to 0.66. The slope of contrast intensity
over time was not informative: [31 HU/s (IQR: 20-57) in CTA with, compared
to 36 HU/s (IQR: 22.5-53) in CTA without RVD, p=0.60]. Conclusion: Several
parameters of the time-intensity curve obtained by the bolus tracking
system are associated with RVD assessed on CTA images. Of those, the time
needed to reach a predefined threshold seems to be the easiest to obtain
in any CTA without additional processing time or contrast injection.
However, the performance of those parameters is globally low.