title: Integrated cardio-thoracic imaging with ECG-Gated 64-slice multidetector-row CT: initial findings in 133 patients.
abstract: The purpose of this study was to investigate the possibility of assessing the underlying respiratory disease as well as cardiac function during ECG-gated CT angiography of the chest with 64-slice multidetector-row CT (MDCT). One hundred thirty-three consecutive patients in sinus rhythm with known or suspected ventricular dysfunction underwent an ECG-gated CT angiographic examination of the chest without beta-blockers using the following parameters: (1) collimation: 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices (Sensation 64; Siemens); rotation time: 0.33 s; pitch: 0.3; 120 kV; 200 mAs; ECG-controlled dose modulation (ECG-pulsing) and (2) 120 ml of a 35% contrast agent. Data were reconstructed: (1) to evaluate the underlying respiratory disease (1-mm thick lung and mediastinal scans reconstructed at 55% of the R-R interval; i.e., "morphologic scans") and (2) to determine right (RVEF) and left (LVEF) ventricular ejection fractions (short-axis systolic and diastolic images; Argus software; i.e., "functional scans"). The mean heart rate was 73 bpm (range: 42-120) and the mean scan time was 18.11 +/- 2.67 s (range: 10-27). A total of 123 examinations (92%) had both lung and mediastinal images rated as diagnostic scans, whereas 10 examinations (8%) had non-diagnostic images altered by the presence of respiratory-motion artifacts (n = 4) or cyclic artifacts related to the use of a pitch value of 0.3 in patients with a very low heart rate during data acquisition (n = 6). Assessment of right and left ventricular function was achievable in 124 patients (93%, 95% CI: 88-97%). For these 124 examinations, the mean RVEF was 46.10% (+/- 9.5; range: 20-72) and the mean LVEF was 58.23% (+/- 10.88; range: 20-83). In the remaining nine patients, an imprecise segmentation of the right and left ventricular cavities was considered as a limiting factor for precise calculation of end-systolic and end-diastolic ventricular volumes. The mean (+/- SD) DLP value of the examinations was 279.86 (+/- 117.50) mGy.cm. Assessment of underlying respiratory disease and cardiac function from the same data set was achievable in 92% of the patients with ECG-gated 64-slice MDCT.
authors.affiliation: Department of Thoracic Imaging, Hospital Calmette, University Center of Lille, Boulevard Jules Leclerc, 59037, LILLE cedex, France.
authors.forename: Randa
authors.initials: R
authors.lastname: Salem
authors.forename: Martine
authors.initials: M
authors.lastname: Remy-Jardin
authors.forename: Damien
authors.initials: D
authors.lastname: Delhaye
authors.forename: Chadi
authors.initials: C
authors.lastname: Khalil
authors.forename: Antoine
authors.initials: A
authors.lastname: Teisseire
authors.forename: Valérie
authors.initials: V
authors.lastname: Delannoy-Deken
authors.forename: Alain
authors.initials: A
authors.lastname: Duhamel
authors.forename: Jacques
authors.initials: J
authors.lastname: Remy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011856:Radiographic Image Enhancement; D013902:Radiography, Thoracic / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*