Incremental value of adenosine-induced stress myocardial perfusion imaging with dual-source CT at cardiac CT angiography

Abstract

Purpose: First, to assess the feasibility of a protocol involving stress-induced perfusion evaluated at computed tomography (CT) combined with cardiac CT angiography in a single examination and second, to assess the incremental value of perfusion imaging over cardiac CT angiography in a dual-source technique for the detection of obstructive coronary artery disease (CAD) in a high-risk population.

Materials and methods: Institutional review board approval and informed patient consent were obtained before patient enrollment in the study. The study was HIPAA compliant. Thirty-five patients at high risk for CAD were prospectively enrolled for evaluation of the feasibility of CT perfusion imaging. All patients underwent retrospectively electrocardiographically gated (helical) adenosine stress CT perfusion imaging followed by prospectively electrocardiographically gated (axial) rest myocardial CT perfusion imaging. Analysis was performed in three steps: (a)Coronary arterial stenoses were scored for severity and reader confidence at cardiac CT angiography, (b)myocardial perfusion defects were identified and scored for severity and reversibility at CT perfusion imaging, and (c)coronary stenosis severity was reclassified according to perfusion findings at combined cardiac CT angiography and CT perfusion imaging. The sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of cardiac CT angiography before and after CT perfusion analysis were calculated.

Results: With use of a reference standard of greater than 50% stenosis at invasive angiography, all parameters of diagnostic accuracy increased after CT perfusion analysis: Sensitivity increased from 83% to 91%; specificity, from 71% to 91%; PPV, from 66% to 86%; and NPV, from 87% to 93%. The area under the receiver operating characteristic curve increased significantly, from 0.77 to 0.90 (P < .005).

Conclusion: A combination protocol involving adenosine perfusion CT imaging and cardiac CT angiography in a dual-source technique is feasible, and CT perfusion adds incremental value to cardiac CT angiography in the detection of significant CAD.

Figure 1a:

Images in 63-year-old man with history of CAD and single episode of neurocardiogenic syncope. (a, d) Curved multiplanar reformatted cardiac CT angiographic images read before the perfusion image reading show (a) mixed proximal left anterior descending arterial lesion (arrow) deemed to be significant stenosis and (d) heavily calcified right coronary artery that was considered noninterpretable. (b, e) Thick short-axis CT perfusion images obtained at midventricular level show inferolateral perfusion defect during stress CT perfusion (arrows in b) that is completely reversible on rest CT perfusion image (arrows in e). (c, f) Reference-standard QCA images show mild disease in left anterior descending (white arrow) and right coronary arteries and subtotal occlusion of left circumflex artery (black arrow) causing a perfusion defect. The left circumflex arterial lesion is also appreciated at cardiac CT angiography (d).

Figure 1b:

Images in 63-year-old man with history of CAD and single episode of neurocardiogenic syncope. (a, d) Curved multiplanar reformatted cardiac CT angiographic images read before the perfusion image reading show (a) mixed proximal left anterior descending arterial lesion (arrow) deemed to be significant stenosis and (d) heavily calcified right coronary artery that was considered noninterpretable. (b, e) Thick short-axis CT perfusion images obtained at midventricular level show inferolateral perfusion defect during stress CT perfusion (arrows in b) that is completely reversible on rest CT perfusion image (arrows in e). (c, f) Reference-standard QCA images show mild disease in left anterior descending (white arrow) and right coronary arteries and subtotal occlusion of left circumflex artery (black arrow) causing a perfusion defect. The left circumflex arterial lesion is also appreciated at cardiac CT angiography (d).

Figure 1c:

Images in 63-year-old man with history of CAD and single episode of neurocardiogenic syncope. (a, d) Curved multiplanar reformatted cardiac CT angiographic images read before the perfusion image reading show (a) mixed proximal left anterior descending arterial lesion (arrow) deemed to be significant stenosis and (d) heavily calcified right coronary artery that was considered noninterpretable. (b, e) Thick short-axis CT perfusion images obtained at midventricular level show inferolateral perfusion defect during stress CT perfusion (arrows in b) that is completely reversible on rest CT perfusion image (arrows in e). (c, f) Reference-standard QCA images show mild disease in left anterior descending (white arrow) and right coronary arteries and subtotal occlusion of left circumflex artery (black arrow) causing a perfusion defect. The left circumflex arterial lesion is also appreciated at cardiac CT angiography (d).

Figure 1d:

Images in 63-year-old man with history of CAD and single episode of neurocardiogenic syncope. (a, d) Curved multiplanar reformatted cardiac CT angiographic images read before the perfusion image reading show (a) mixed proximal left anterior descending arterial lesion (arrow) deemed to be significant stenosis and (d) heavily calcified right coronary artery that was considered noninterpretable. (b, e) Thick short-axis CT perfusion images obtained at midventricular level show inferolateral perfusion defect during stress CT perfusion (arrows in b) that is completely reversible on rest CT perfusion image (arrows in e). (c, f) Reference-standard QCA images show mild disease in left anterior descending (white arrow) and right coronary arteries and subtotal occlusion of left circumflex artery (black arrow) causing a perfusion defect. The left circumflex arterial lesion is also appreciated at cardiac CT angiography (d).

Figure 1e:

Images in 63-year-old man with history of CAD and single episode of neurocardiogenic syncope. (a, d) Curved multiplanar reformatted cardiac CT angiographic images read before the perfusion image reading show (a) mixed proximal left anterior descending arterial lesion (arrow) deemed to be significant stenosis and (d) heavily calcified right coronary artery that was considered noninterpretable. (b, e) Thick short-axis CT perfusion images obtained at midventricular level show inferolateral perfusion defect during stress CT perfusion (arrows in b) that is completely reversible on rest CT perfusion image (arrows in e). (c, f) Reference-standard QCA images show mild disease in left anterior descending (white arrow) and right coronary arteries and subtotal occlusion of left circumflex artery (black arrow) causing a perfusion defect. The left circumflex arterial lesion is also appreciated at cardiac CT angiography (d).

Figure 1f:

Images in 63-year-old man with history of CAD and single episode of neurocardiogenic syncope. (a, d) Curved multiplanar reformatted cardiac CT angiographic images read before the perfusion image reading show (a) mixed proximal left anterior descending arterial lesion (arrow) deemed to be significant stenosis and (d) heavily calcified right coronary artery that was considered noninterpretable. (b, e) Thick short-axis CT perfusion images obtained at midventricular level show inferolateral perfusion defect during stress CT perfusion (arrows in b) that is completely reversible on rest CT perfusion image (arrows in e). (c, f) Reference-standard QCA images show mild disease in left anterior descending (white arrow) and right coronary arteries and subtotal occlusion of left circumflex artery (black arrow) causing a perfusion defect. The left circumflex arterial lesion is also appreciated at cardiac CT angiography (d).

Figure 2a:

Images in 51-year-old man with history of diabetes mellitus who presented with typical angina. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows prominent motion artifact in right coronary artery (arrows) that persisted through all cardiac phases. (b, d) Thick short-axis CT perfusion images obtained at midventricular levels show perfusion defect (arrows in b) during stress CT perfusion in the inferior and inferolateral segments that is partially reversible during rest CT perfusion (arrows in d). (c)Reference-standard invasive angiogram findings confirm the presence of severely stenotic lesion in right coronary artery (arrow) that was seen at postperfusion cardiac CT angiographic image reading.

Figure 2b:

Images in 51-year-old man with history of diabetes mellitus who presented with typical angina. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows prominent motion artifact in right coronary artery (arrows) that persisted through all cardiac phases. (b, d) Thick short-axis CT perfusion images obtained at midventricular levels show perfusion defect (arrows in b) during stress CT perfusion in the inferior and inferolateral segments that is partially reversible during rest CT perfusion (arrows in d). (c)Reference-standard invasive angiogram findings confirm the presence of severely stenotic lesion in right coronary artery (arrow) that was seen at postperfusion cardiac CT angiographic image reading.

Figure 2c:

Images in 51-year-old man with history of diabetes mellitus who presented with typical angina. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows prominent motion artifact in right coronary artery (arrows) that persisted through all cardiac phases. (b, d) Thick short-axis CT perfusion images obtained at midventricular levels show perfusion defect (arrows in b) during stress CT perfusion in the inferior and inferolateral segments that is partially reversible during rest CT perfusion (arrows in d). (c)Reference-standard invasive angiogram findings confirm the presence of severely stenotic lesion in right coronary artery (arrow) that was seen at postperfusion cardiac CT angiographic image reading.

Figure 2d:

Images in 51-year-old man with history of diabetes mellitus who presented with typical angina. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows prominent motion artifact in right coronary artery (arrows) that persisted through all cardiac phases. (b, d) Thick short-axis CT perfusion images obtained at midventricular levels show perfusion defect (arrows in b) during stress CT perfusion in the inferior and inferolateral segments that is partially reversible during rest CT perfusion (arrows in d). (c)Reference-standard invasive angiogram findings confirm the presence of severely stenotic lesion in right coronary artery (arrow) that was seen at postperfusion cardiac CT angiographic image reading.

Figure 3a:

Images in 70-year-old man with history of diabetes mellitus and CAD. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows stent in proximal left anterior descending artery, with proximal calcified plaque that was deemed to be significant disease (arrow). (b, d) Thick short-axis CT perfusion images obtained at midventricular level show no perfusion defect on (b) stress CT perfusion (arrows) or (d) rest CT perfusion (arrows) images in the left anterior descending distribution. (c)Reference-standard invasive angiogram findings confirm the absence of significant disease in left anterior descending distribution (arrow) determined at postperfusion cardiac CT angiographic image reading.

Figure 3b:

Images in 70-year-old man with history of diabetes mellitus and CAD. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows stent in proximal left anterior descending artery, with proximal calcified plaque that was deemed to be significant disease (arrow). (b, d) Thick short-axis CT perfusion images obtained at midventricular level show no perfusion defect on (b) stress CT perfusion (arrows) or (d) rest CT perfusion (arrows) images in the left anterior descending distribution. (c)Reference-standard invasive angiogram findings confirm the absence of significant disease in left anterior descending distribution (arrow) determined at postperfusion cardiac CT angiographic image reading.

Figure 3c:

Images in 70-year-old man with history of diabetes mellitus and CAD. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows stent in proximal left anterior descending artery, with proximal calcified plaque that was deemed to be significant disease (arrow). (b, d) Thick short-axis CT perfusion images obtained at midventricular level show no perfusion defect on (b) stress CT perfusion (arrows) or (d) rest CT perfusion (arrows) images in the left anterior descending distribution. (c)Reference-standard invasive angiogram findings confirm the absence of significant disease in left anterior descending distribution (arrow) determined at postperfusion cardiac CT angiographic image reading.

Figure 3d:

Images in 70-year-old man with history of diabetes mellitus and CAD. (a) Curved multiplanar reformatted cardiac CT angiographic image read before perfusion image reading shows stent in proximal left anterior descending artery, with proximal calcified plaque that was deemed to be significant disease (arrow). (b, d) Thick short-axis CT perfusion images obtained at midventricular level show no perfusion defect on (b) stress CT perfusion (arrows) or (d) rest CT perfusion (arrows) images in the left anterior descending distribution. (c)Reference-standard invasive angiogram findings confirm the absence of significant disease in left anterior descending distribution (arrow) determined at postperfusion cardiac CT angiographic image reading.