Validation and application of single breath-hold cine cardiac MR for ventricular function assessment in children with congenital heart disease at rest and during adenosine stress.

PURPOSE: To validate the accuracy of ventricular function analysis using a single breath-hold real-time steady sate free precession (SSFP) cine MR method and demonstrate its application during adenosine stress imaging in children with congenital heart disease. MATERIALS AND METHODS: Twenty-eight subjects with congenital heart disease were studied (mean age 12.4 +/- 2.3 years) with MR imaging at 1.5 T. Short-axis images covering the entirety of both ventricles were acquired at rest, with a conventional segmented SSFP cine sequence acquired over multiple breath-holds and a single breath-hold real-time SSFP sequence. Seventeen subjects were given an infusion of adenosine, and the single breath-hold real-time short-axis stack was repeated during stress. Two independent observers performed the ventricular function analysis. Data was compared between the 2 acquisition methods at rest and between the single breath-hold acquisition at rest and during adenosine stress. RESULTS: There was good agreement between the multiple breath-hold and single breath-hold methods for measurement of end-diastolic volume (r = 0.95 and 0.96, p < .0001) and end-systolic volume (ESV) (r = 0.76 and 0.90, p < .0001) for the left and right ventricles respectively, and the left ventricular mass (r = 0.97, p < .0001). Adenosine was administered safely to all subjects. During stress there were significant changes in the heart rate and ESV, which led to a significant increase in cardiac output (mean 1.5 +/- 1.0 L/min, p < .001). CONCLUSION: Single breath-hold real-time SSFP cine imaging is robust and accurate in assessing cardiac function in children with congenital heart disease. An application of this method is the rapid assessment of cardiac function during adenosine stress.

Coronary artery calcium scoring using ECG-gated multidetector CT: effect of individually optimized image-reconstruction windows on image quality and measurement reproducibility.

OBJECTIVE: We studied the effect of using individually optimized image-reconstruction windows on image quality and measurement reproducibility in coronary artery calcium scoring using ECG-gated multidetector CT (MDCT). SUBJECTS AND METHODS: In 50 patients, the coronary arteries were investigated twice with ECG-gated MDCT with 500-msec rotation time. Per scan, three sets of images were reconstructed, respectively, at an image-reconstruction window of 40%, 50%, and 60% of the R-R interval. Image quality was assessed, and the optimal image-reconstruction window per scan and per coronary territory was determined. The interscan variability of calcium mass measurements was calculated for different strategies (use of fixed image-reconstruction window [40%, 50%, or 60%] versus individually optimized image-reconstruction window). RESULTS: A significant improvement in image quality was obtained by selecting the best of three reconstructed data sets (mean image quality score, 4.4 vs 3.7; p < 0.001). Even with individually optimized image-reconstruction window values, we obtained high values for interscan variability (mean +/- SD, 27% +/- 22% vs 31% +/- 35% with a fixed image-reconstruction window). CONCLUSION: The use of individually optimized image-reconstruction windows leads to a significant improvement in image quality. However, interscan variability of calcium mass measurements remains high.