Non-invasive intravenous coronary angiography using electron beam tomography and multislice computed tomography

Abstract

Background: Electron beam computed tomography (EBCT) and multislice computed tomography (MSCT) are both suitable for non-invasive identification of coronary stenoses. Objective: To compare intravenous coronary EBCT angiography (EBCTA) and MSCT angiography (MSCTA) with regard to image quality and diagnostic accuracy. Methods: EBCTA was done using an Imatron C-150 XP scanner in 101 patients following a standard protocol (slice thickness 3 mm, overlap 1 mm, acquisition time 100 ms, prospective ECG trigger). For MSCTA in a different set of 91 patients (using a Siemens Somatom Plus4VZ scanner), the whole volume of the heart was covered in a spiral technique by four simultaneous detector rows. Using retrospective ECG gating, the raw data were reconstructed in (mean (SD)) 215 (12) axial slices acquired in diastole (slice thickness 1.25 mm, overlap 0.5 mm, acquisition time 250 ms/slice). Results: With EBCTA, 76% of predetermined coronary segments in a nine segment model could be assessed with diagnostic image quality, and with MSCTA, 82%. A low contrast to noise ratio with EBCTA, and the presence of motion artefacts with MSCTA were the main reasons for inadequate image quality. Using conventional angiography as the gold standard, 77% of stenoses of > 50% could be identified correctly with EBCTA and 82% with MSCTA. Significant stenoses were correctly ruled out in 93% of segments with EBCTA, and in 96% of segments with MSCTA. The average contrast to noise ratio was higher with MSCTA than with EBCTA (9.4 v 6.5; p < 0.001).Conclusions: EBCTA and MSCTA show similarly high levels of accuracy for determining and ruling out significant coronary artery stenoses. MSCTA is capable of providing good image quality in more coronary segments than EBCTA because of its better contrast to noise ratio and higher spatial resolution. Motion artefacts seen at heart rates of > 75 beats/min and a higher radiation exposure are the main limitations of MSCTA.

Noninvasive Angiography and Assessment of Left Ventricular Function Using Multislice Computed Tomography in Patients With Type 2 Diabetes

“…Still, our results are very similar to those obtained in the few available comparisons between MSCT and MRI (13,14). Third, in the present study, 14% of coronary segments were uninterpretable, which is in line with previous studies (6,11,22). However, with the introduction of 32-and 64-slice systems, the percentage of uninterpretable segments is likely to decline further.…”

“…A promising new imaging technique for the noninvasive detection of CAD is multislice computed tomography (MSCT), which allows the acquisition of high-quality images of the entire heart within a single breathhold. Several studies have demonstrated the technique to be useful in the detection of coronary artery stenoses with sensitivities and specificities ranging from 72 to 95% and 75 to 99%, respectively (5)(6)(7)(8)(9)(10)(11).…”

Transitioning from 16-slice to 64-slice multidetector computed tomography for the assessment of coronary artery disease: Are we really making progress?

“…Initially, MDCT lacked the capacity to evaluate coronary artery stenosis, with diagnostic accuracies for four-slice MDCT ranging from 78% to 93% (3,4). Additionally, MDCT was unable to assess almost one-quarter of all coronary artery segments due to poor image quality.…”

Noninvasive Evaluation of the Coronary Arteries With Multislice Computed Tomography in Hypertensive Patients

“…Similar percentages have been reported previously. 13,19,27 In the near future, however, this limitation may be overcome by the introduction of 32-detector and 64-detector row scanners in combination with faster rotation times, which are likely to reduce the percentage of nonassessable segments. Second, an important drawback of MSCT is the radiation dose that is still considerably high: Ϸ8 mSv.…”