New applications for noninvasive cardiac imaging: dual-source computed tomography.
Coronary catheter angiography is considered to be the standard of reference for the diagnosis of coronary artery disease (CAD) and the grading of coronary artery stenoses. Even with the established generation of 16- and 64-multislice CT (MSCT) systems, with remarkable results reported for diagnostic accuracy, a substantial number of limitations remain, hindering full acceptance of the method as a standard technique in the clinical cascade for CAD patients. Recently, dual-source CT (DSCT) with improved temporal resolution has been introduced into clinical routine, raising the hope that some of the earlier problems might be overcome. MSCTA with 64-slice CT scanners has successfully been validated for the evaluation of clinically relevant lumen reduction of the coronary arteries with high negative predictive values and for the simultaneous assessment of pulmonary embolism, coronary artery stenoses, and aortic dissection and aneurysm in patients with chest pain ("triple rule out"). However, certain limitations continue to exist including partial volume effects due to heavy calcium deposits in the coronary artery wall, impaired assessability of coronary artery branches smaller than 2 mm in diameter, and impaired assessability of patients with a high heart rate and/or arrhythmia. While MSCT has mainly been tested to detect obstructive CAD, an accurate assessment of regional and global ventricular function, as well as of the aortic and mitral valves, might be feasible using DSCT, since image reconstruction is possible in virtually any phase of the cardiac cycle with a sufficiently high temporal resolution. DSCT is a robust method for the evaluation of patients with higher heart rates and arrhythmias and, in most cases, obviates the need for beta-blocker premedication. While the evaluation of coronary artery stenoses will remain the primary clinical indication for cardiac DSCT, a simultaneous and sufficiently accurate assessment of global left ventricular functional parameters, regional wall motion, and valve assessment becomes feasible with a single scan.
Rist
Carsten
C
Department of Clinical Radiology, University Hospitals-Grosshadern, Ludwig-Maximilians University, Munich, Germany. carsten.rist@med.uni-muenchen.de
Johnson
Thorsten R
TR
Becker
Christoph R
CR
Reiser
Maximilian F
MF
Nikolaou
Konstantin
K
D016477:Artifacts; D002637:Chest Pain / Q000000981:diagnostic imaging; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D006801:Humans; D011237:Predictive Value of Tests; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media