They include wider detector arrays that allow higher numbers of simultaneously acquired image slices, faster x-ray tube rotation times, and the use of alternative image reconstruction techniques that target image noise, all of which could improve the diagnostic value of CCTA in currently challenging scenarios, such as calcified coronary arteries and coronary stents. The improvement also will foster the study and clinical use of newer applications of cardiac CT, such as coronary plaque characterization, late enhancement imaging for the detection of myocardial scar, and MPI to detect myocardial ischemia.1252 Efforts currently under way to obtain perfusion information from CCTA images are promising,196 201 with one report also calculating FFR with CCTA.195 Moreover, plaque quantification soft- ware is in development and could further guide accurate detection of atherosclerotic disease burden.1253 Several new developments in stress nuclear MPI have occurred, including new radioisotopes: 1) an F18 PET perfu- sion agent (in Phase III trials), which will allow exercise PET I-beta-methyl-iodophenylpentadecanoic acid SPECT, with the unique ability to document metabolic alterations representing prior ischemic episodes (ie, ischemic I-labeled meta-iodobenzylguanidine SPECT, which could be helpful for assessment of arrhythmic risk in SIHD patients.1254 Several new SPECT cameras also have been introduced into the marketplace and offer the opportunity for improved image quality within a substantially shorter time period and with a lower radiation dose.1255,1256 Several studies have correlated atherosclerotic plaque char- acteristics with the extent of ischemic myocardium by stress nuclear MPI.202 206,215 Finally, the diagnostic and prognostic value of PET flow reserve data is currently under intense Echocardiography, being the most portable and widely available stress imaging technique, has developed novel methods that are promising in the assessment of SIHD patient. 