Non-Invasive Assessment and Clinical Strategy of Stable Coronary Artery Disease by Magnetic Resonance Imaging, Multislice Computed Tomography and Myocardial Perfusion SPECT

Abstract

Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp ecent development in non-invasive imaging modalities, such as multislice computed tomography (MSCT) and magnetic resonance imaging (MRI), have gained great attention in the field of diagnostic cardiology, especially in the diagnosis of coronary artery disease (CAD). These imaging modalities have clinical advantages over other imaging techniques including stress echocardiography and stress single-photon emission computed tomography (SPECT), because they permit direct visualization of the coronary artery rather than showing indirect evidence of CAD, such as stress-induced wall motion abnormalities and myocardial perfusion defects. Moreover, MSCT provides additional information to conventional coronary angiography, that is, the coronary artery plaque texture. However, coronary MSCT angiography is not a totally non-invasive method because it requires radiation exposure and contrast medium, which might be harmful in a certain number of patients. 1 However, coronary magnetic resonance angiography (MRA), which requires no radiation exposure or contrast medium can be performed safely, and it has potential to become a routine screening tool for participants with low likelihood of CAD, but currently available equipments do not provide information of coronary artery plaques so far. In this review, we discuss advantages and disadvantages of coronary MSCT angiography and MRA. We also discuss the role of myocardial perfusion imaging using myocardial perfusion SPECT in the determination of therapeutic strategies. Coronary MSCT Angiography Detection of Coronary Artery Stenoses and OcclusionsWe have shown, for the first time in Japan, that MSCT has potential to become the first choice of diagnostic modality for patients with suspected CAD and that MSCT would replace diagnostic coronary angiography. 2,3 The sensitivity and specificity of the first generation of MSCT (4 detector-row equipment) for the detection of angiographically significant CAD was 94% and 97%, respectively. In the era of 64 detectorrow MSCT, the diagnostic accuracy was increased because of improvements in spatial and temporal resolution; the accuracy had a sensitivity of 95-97% and specificity of 93-98%. 4-7 On segment-based analysis, 8 to 12% of coronary segments were not assessable due to heavily calcification, arrhythmia and motion artifacts. 6-9 However, coronary MSCT angiography has several shortcomings. First, evaluation of severely calcified coronary artery lesions is sometimes difficult because of overestimation of the size of calcium deposit due to partial volume effect, leading to overestimation of coronary artery stenosis. Dual-energy CT equipments that provide 2 different X-ray energy sources might allow clear Coronary multislice computed tomography (MSCT) angiography and magnetic resonance angiography (MRA) have emerged as new diagnostic techniques that allow direct visualization of the coronary artery. These new modalities have both advantages and dis...

Cardiac Event Risk in Japanese Subjects Estimated Using Gated Myocardial Perfusion Imaging, in Conjunction With Diabetes Mellitus and Chronic Kidney Disease

“…23 It has also been noted that induced ischemia was one of the major determinants for patient management. 3, 25 In other words, low-risk patients were considered to be suitable for medical treatment, and high-risk patients required more aggressive treatment including coronary revascularization. Hachamovitch et al found that patients with >10% ischemia could expect more beneficial effects from coronary revascularization.…”

Combined Assessment of Myocardial Perfusion and Function by ECG-Gated Myocardial Perfusion Single-Photon Emission Computed Tomography for the Prediction of Future Cardiac Events in Patients With Type 2 Diabetes Mellitus

“…We have previously documented that myocardial perfusion SPECT could be used to predict future cardiac events (nonfatal AMI and cardiac death (CD)) in a Japanese population. [7][8][9] In the present study we investigated whether ECG-gated SPECT can still give prognostic information for patients with DM in terms of those major cardiac events. Recently, a Japanese assessment of cardiac events and survival by quantitative gated SPECT (J-ACCESS 2) in patients with asymptomatic DM documented the short-term cardiac event rates (ie, in 1 year).…”

Estimation of Cardiac Event Risk by Gated Myocardial Perfusion Imaging and Quantitative Scoring Methods Based on a Multi-Center J-ACCESS Database

“…5, 19 In a Japanese population using MPI, a study demonstrated that advanced age, SSS, and summed difference score were independent predictors of cardiac death. 20, 21 The equation for predicting cardiac events was based on multi-variate analysis of J-ACCESS investigation. Based on a 3-year follow-up study of 4,629 patients, major cardiac events including cardiac death, non-fatal myocardial infarction, and severe heart failure requiring hospitalization could be estimated.…”