Klinische Wertigkeit der Dual-Source-Computertomographie (DSCT) in der Primärdiagnostik der koronaren Herzkrankheit

Dual-source-CT-technology (DSCT) improves temporal resolution of cardiac computed tomography to 83 ms per heart-phase. In this study, the clinical performance of this new method is evaluated.

Materials and Methods

In fifty patients (33 male, 17 female; age 50±13 years) with suspected coronary heart disease, CT angiography (slice thickness 0,75 mm, contrast-agent 60–80 ml iomeprol) was performed with a Somatom Definition scanner. Based on the coronary 15-segment-model of the AHA, scores for image quality and lumen reduction were established to enable the observer, to give recommendations for further therapy.

Results

Out of 750 possible AHA-segments, 655 were depicted (87,3%). 591 segments (90,2%) were assessed without any limitation of quality, 49 (7,5%) segments showed moderate, and 15 (2,3%) segments severe limitation in image quality. 508 (77,6%) segments were without pathological findings, 92 (14,0%) segments had minimal atherosclerotic lesions, 42 (6,4%) segments suffered from stenoses with lumen reduction less than 70%, and 13 (2,0%) showed significant stenoses of more than 70%. In 31 patients (62%), coronary heart disease was ruled out by CT angiography without any need for further non-invasive or invasive diagnostics. 8 patients (16%) underwent stress-testing for ischemia. In 11 (22%) patients coronary angiography was recommended, and DSCT findings were confirmed in 10 cases. Only one LCx stenosis was overestimated in DSCT.

Conclusion

Contrast-enhanced DSCT is a powerful tool in diagnosis of coronary heart disease. 98% of coronary segments could be assessed in diagnostic quality, and at least 90% of haemodynamically significant coronary stenoses were detected.