Two- and three-dimensional CT ventriculography: A new application of helical CT

OBJECTIVE. We propose a new application of helical CT, CT ventriculography, which can produce two-dimensional (2D) and three-dimensional (3D) images o f different cardiac phases (plus animation). We sought to determine the acc uracy of CT ventriculography for assessing left ventricular volumes. MATERIALS AND METHODS. With a single breath-hold, the patient's entire hear t was scanned with an ECG-gating technique (3-mm-thick collimation, 2 mm pe r rotation table speed, 0.8 sec per rotation, and 50 rotations through 10 c m in total). Using a 0.2-mm (0.08-sec) interval (10 slices per rotation) ov erlapping reconstruction, about 500 axial slices were obtained and reordere d to separate different cardiac cycles. Then, 2D cardiac axes and 3D images were reconstructed and animated movies of the 2D and 3D images were produc ed. In 21 patients, the left ventricular end-diastolic volume, end-systolic volume, and ejection fraction were assessed and compared with left ventric ulography. Correlations and agreements between CT and left ventriculography were determined. RESULTS, Close correlations between CT and left ventriculography were obtai ned (r = 0.95, 0.98, and 0.91, for end-diastolic volume, end-systolic volum e, and left ventricular ejection fraction, respectively; p < 0.0001 for all values). The limits of agreement between CT and left ventriculography were 44.3 to -44.5 ml for end-diastolic volume, 19.8 to -29.0 ml for end-systol ic volume, and 19.7% to -9.5% for left ventricular ejection fraction. CONCLUSION. This cardiac application of helical CT provides a clear morphol ogy along the cardiac axes and 3D images and an assessment of left ventricu lar volumes (end-diastolic volume, end-systolic volume, and left ventricula r ejection fraction).