RESULTS

We retrospectively identified 49 patients who met the inclusion criteria. Their characteristics are presented in Table 1. They had 63 CMR and 2D TTE exams allowing measurements adequate for analysis and comparison. The means, SDs, and reference ranges of the RVOT diameters by CMR and 2D TTE, indexed to BSA, are presented in Table 2.
Figure 3 and Figure 4 show the correlation between the CMR and 2D TTE measurements. The RVOT diameter measured in the strict transverse view by CMR exhibited very strong correlation with the similar PSAX view by 2D TTE (r = 0.84; p <0.0001), and the RVOT diameter measured in the strict sagittal view by CMR exhibited strong correlation with the similar PLAX view by 2D TTE (r = 0.78;p <0.0001).
Figure 5 and Figure 6 show the agreement between the CMR and 2D TTE measurements. The RVOT diameter measurements in the strict transverse view by CMR and the similar PSAX view by 2D TTE exhibited poor agreement with significant bias (bias = -3.34 mm/m2 or -16.6%; SD of bias = 2.81 mm/m2 or 14.6%). The RVOT diameter measurements in the strict sagittal view by CMR and the similar PLAX view by 2D TTE also exhibited poor agreement with significant bias (bias = -3.90 mm/m2 or -19.7%; SD of bias = 3.18 mm/m2 or 13.4%).