Accuracy of right ventricular volume and function assessed with cardiovascular magnetic resonance: comparison with echocardiographic parameters.

BACKGROUND: Cardiac magnetic resonance imaging (MRI) is an essential imaging method used to assess patients with diseases of the left and right ventricles. Cardiac MRI is the gold standard for right ventricular measurements; however, the most suitable method for volumetric analysis of the right ventricle remains controversial. AIMS: To compare the accuracy of the short axis and four-chamber view segmentation methods in assessing the right ventricle in cardiac MRI studies, to determine the reproducibility of cardiac MR measurements, and to correlate cardiac MR methods with frequently used echocardiographic methods. METHODS: Eighty patients with different clinical indications were studied using a 1.5-Tesla resonance magnetic unit. In all patients, the end-diastolic volume, end-systolic volume, and right ventricle ejection fraction were measured in the short axis and four-chamber views. Twenty-three patients also underwent echocardiography on the same day the cardiac MRI was completed. RESULTS: Cardiac MRI revealed no statistically significant differences in the volume or function of the right ventricle, calculated by the two segmentation methods (p > 0.05). The correlation was excellent between both planes in the assessment of the volume (concordance correlation coefficient [CCC] = 0.97) and the ejection fraction (CCC = 0.90). The correlation was low between the right ventricular ejection fraction and the echocardiographic methods (CCC = 0.02 and CCC = 0.01). CONCLUSION: Right ventricular function in normal ventricles and in dilated ventricles was appropriately measured by cardiac MRI using either of the two segmentation methods. Both methods were highly accurate. However, the correlation with echocardiographic methods was rather poor.

Quantification of Right and Left Ventricular Function in Cardiac MR Imaging: Comparison of Semiautomatic and Manual Segmentation Algorithms.

The purpose of this study was to evaluate the performance of a semiautomatic segmentation method for the anatomical and functional assessment of both ventricles from cardiac cine magnetic resonance (MR) examinations, reducing user interaction to a "mouse-click". Fifty-two patients with cardiovascular diseases were examined using a 1.5-T MR imaging unit. Several parameters of both ventricles, such as end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF), were quantified by an experienced operator using the conventional method based on manually-defined contours, as the standard of reference; and a novel semiautomatic segmentation method based on edge detection, iterative thresholding and region growing techniques, for evaluation purposes. No statistically significant differences were found between the two measurement values obtained for each parameter (p > 0.05). Correlation to estimate right ventricular function was good (r > 0.8) and turned out to be excellent (r > 0.9) for the left ventricle (LV). Bland-Altman plots revealed acceptable limits of agreement between the two methods (95%). Our study findings indicate that the proposed technique allows a fast and accurate assessment of both ventricles. However, further improvements are needed to equal results achieved for the right ventricle (RV) using the conventional methodology.