Skip Navigation LinksHome > September 2012 - Volume 27 - Issue 5 > The Variability in Prognostic Values of Right Ventricular-to...
Journal of Thoracic Imaging:
doi: 10.1097/RTI.0b013e3182350a35
Original Articles

The Variability in Prognostic Values of Right Ventricular-to-Left Ventricular Diameter Ratios Derived From Different Measurement Methods on Computed Tomography Pulmonary Angiography: A Patient Outcome Study

Kumamaru, Kanako K. MD; Hunsaker, Andetta R. MD; Wake, Nicole MS; Lu, Michael T. MD; Signorelli, Jason BS; Bedayat, Arash MD; Rybicki, Frank J. MD, PhD

Collapse Box

Abstract

Purpose: To evaluate variability in right ventricular-to-left ventricular (RV/LV) diameter ratios introduced by differences in measurement methods and the subsequent influence on the accuracy of predicting outcomes for patients with acute pulmonary embolism (PE).

Materials and Methods: For 200 consecutive computed tomography pulmonary angiograms positive for acute PE, RV/LV diameter ratios were retrospectively measured using 3 different 4-chamber reformations and from axial images alone. The first 4-chamber reformation method (4ch-1) was a single oblique technique using LV morphology landmarks; the other 2 methods (4ch-2 and 4ch-3) were double oblique techniques that created an intermediate short-axis image to identify the maximum RV diameter but with different approaches to reach short-axis images. Interobserver variability was measured using 30 cases. Receiver-operating characteristic analysis compared the accuracy of predicting outcomes among the 4 measurements for PE-related death, and for death or the need for intensive therapies (composite outcome).

Results: The difference in median RV/LV diameter ratios was insignificant among 4ch-2 (1.01), 4ch-3 (1.02), and axial (1.03) datasets, whereas that from 4ch-1 (0.93) was significantly lower (P<0.001). Correlation between observers was excellent for all 4 datasets (r=0.881 to 0.925). Compared with 4ch-1, the other 3 datasets equally achieved higher accuracy in predicting PE-related 30-day mortality (area under curve: 0.55 vs. 0.69 to 0.73, P=0.007 to 0.019) and a composite outcome (area under curve: 0.65 vs. 0.77 to 0.78, P=0.003 to 0.010).

Conclusions: Double oblique 4-chamber reformation methods that use intermediate short-axis images to optimize RV size predict outcomes better in patients with acute PE than do single oblique methods using only LV landmarks; however, their accuracy is not superior to that from measurements based on axial images.

© 2012 Lippincott Williams & Wilkins, Inc.

Login

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.