Correlation of Cardiac CTA to Conventional Cardiac Angiography in Diagnosing Coronary Artery Stenosis in a Community Based Center

Transcription

1 Correlation of Cardiac CTA to Conventional Cardiac Angiography in Diagnosing Coronary Artery Stenosis in a Community Based Center Mathieu Sabbagh, R3 Michigan State University Radiology Garden City Hospital Dennis P. Vollman, DO FAOCR Program Director Garden City Hospital 1

2 Disclosures Scientific Electronic Exhibit: Chest Radiology Michigan State Radiology - Garden City Division No disclosures or conflicts of interest. 2

3 Learning Objectives To correlate Cardiac CTA to Conventional Cardiac Angiography in diagnosing coronary artery stenosis in a community center. To review current literature comparing Cardiac CTA to Conventional Cardiac Angiography. To illustrate the capability of Cardiac CTA to identify significant cardiac pathology other than coronary artery disease. 3

4 Figure 1: The red arrow indicates 60% stenosis of the LAD on Cardia CTA. The blue arrow demonstrates a 60% stenosis of the LAD on coronary angiogram. 4

5 Study Purpose To correlate Cardiac CTA to Conventional Cardiac Angiography in diagnosing coronary artery stenosis in a community based center and to illustrate the capability of Cardiac CTA to identify significant cardiac pathology. 5

6 Figure 2: Partial calcified and soft plaque causing 40-60% stenosis of the LAD (red arrow). 6

7 Figure 3: The red arrow illustrates a mid right coronary artery 50% stenosis. 7

8 Background Cardiac CTA has been shown to be a useful noninvasive study to identify coronary artery stenosis and may even be considered a noninvasive alternative to diagnostic cardiac angiography. 1 Cardiac CTA is especially efficient at demonstrating the lack of coronary artery stenosis, hence ruling out coronary artery disease as a source of angina. Limitations to cardiac CTA include: inadequate spatial resolution, inadequate temporal resolution, severe coronary calcification, and suboptimal depiction of coronary plaque. 2 However, previous studies have shown cardiac CTA to have a sensitivity of 96-99% and specificity of 88-91% in identifying coronary artery disease. 3 8

9 Figure 4: Anomalous Origin of the left main coronary artery from the right main coronary artery on CTA (red arrow) and cardiac angiogram (blue arrow). 9

10 Methods A retrospective analysis 69 cardiac CTA studies was performed. The studies were done over a period of 7 years at a community based center. A cardiac CTA protocol was utilized using gated imaging with a Siemens 64 slice helical computed tomography scanner. Medical therapy with the use of a beta blocker and sublingual nitroglycerin tablet was utilized to achieve an ideal pulse rate and to dilate the coronary artery vessels, respectively. 10

11 Figure 5: Dilated Aortic root indicated by the red arrows. 11

12 Results Thirteen of the 69 cardiac CTAs were followed up with cardiac angiograms, two of which were failed attempts and could not be compared to cardiac CTA. One of the remaining cardiac CTA studies was nondiagnostic and could not be directly compared to its associated cardiac angiogram. Thus, 10 Cardiac CTAs were retrospectively compared to cardiac angiograms performed over a period of 7 years. 12

13 Figure 6: CTA 3 dimensional reconstruction demonstrating the right (red arrow) and left (blue arrow) main coronary arteries. 13

14 Results Of the 10 Cardiac CTAs utilized for this study: Three studies demonstrated similar results of no significant coronary artery stenosis. Four studies illustrated similar coronary artery stenosis (Figure 1, 2, and 3). Two studies depicted concordant aberrant or malignant anatomy (Figure 4). Only two studies had discordant findings of stenosis involving different coronary vessels or had significant dissimilar degree of stenosis. 14

15 Figure 7: CTA 3 dimensional reconstruction depicting the left anterior descending artery (red arrow). 15

16 Discussion Although this retrospective study is limited by its low power with only 10 cardiac CTAs directly compared to cardiac angiograms, it did demonstrate that even at a community based center there is an 80% concordance of findings made on cardiac CTA to conventional angiogram. Other substantial anatomical anomalies such as an aberrant left main coronary artery arising from the right main coronary artery and dilated aortic root were easily elucidated with cardiac CTA. These findings support the idea that cardiac CTA should be used more prevalently in the workup of angina alongside other radiology studies such as nuclear medicine cardiac stress tests. 16

17 Figure 8: CTA 3 dimensional reconstruction illustrating the left anterior descending (red arrow) and left circumflex artery (blue arrow) along the lateral posterior aspect of the heart. 17

18 Conclusion Cardiac CTA remains a viable noninvasive option in determining coronary artery stenosis and guiding later intervention in a patient with coronary artery disease. 18

19 References 1. Moscariello A, Vliegenthart R, Schoepf UJ, et al. Coronary CT Angiography versus Conventional Cardiac Angiography for Therapeutic Decision Making in Patients with High Likelihood of Coronary Artery Disease. Radiology. 2012;265(2): Machida H, Tanaka I, Fukui R, et al. Current and Novel Imaging Techniques in Coronary CT. RadioGraphics. 2015;35(4): Halpern EJ. Clinical applications of cardiac CT angiography. Insights into Imaging. 2010;1(4):