Cardiac PET-CT: advanced hybrid imaging for the detection of coronary artery disease

Abstract

Hybrid imaging of positron emission tomography (PET) together with computed tomography (CT) is rapidly emerging. In cardiology, this new advanced hybrid imaging modality allows quantification of cardiac perfusion in combination with assessment of coronary anatomy within a single scanning session of less than 45 minutes. The near-simultaneous anatomical evaluation of coronary arteries using CT and corresponding functional status using PET provides a wealth of complementary information in patients who are being evaluated for (suspected) coronary artery disease, and could help guide clinical patient management in a novel manner. Clinical experience gained with this recently introduced advanced hybrid imaging tool, however, is still limited and its implementation into daily clinical practice remains largely unchartered territory. This review discusses principles of perfusion PET, its diagnostic accuracy, and potential clinical applications of cardiac PET-CT in patients with ischaemic heart disease. (Neth Heart J 2010;18:90-8.).

Myocardial Oxygen Extraction Fraction Measured Using Bolus Inhalation of 15O-Oxygen Gas and Dynamic PET

“…In principle, parametric MBF or PTF images could be used for ROI definition instead. Although it was not possible to construct parametric MBF and PTF images of sufficient image quality using the 2-dimensional PET data in the present study, state-of-the-art PET/CT scanners with much improved scan statistics do allow for generation of good-quality parametric images and C 15 O scans will no longer be needed for delineation of myocardial segments (15,16). Apart from increasing patient comfort because of the shorter duration of the total procedure, this method also decreases the possibility of errors due to patient movement between the different scans.…”

Hybrid Imaging Using Quantitative H215O PET and CT-Based Coronary Angiography for the Detection of Coronary Artery Disease

“…Therefore, the noninvasive combined assessment of coronary anatomy and perfusion can yield complementary information and may reduce the number of diagnostic invasive coronary angiographies (ICAs) by a more judicious referral of patients to the catheterization lab. The integration of anatomy and function is possible within a single scan session with the currently available cardiac PET/CT protocols (4)(5)(6). PET has the unique ability to quantify myocardial blood flow (MBF) in absolute terms, generally with less radiation exposure to the patient, as compared with SPECT (7).…”

Low-Dose Quantitative Myocardial Blood Flow Imaging Using 15O-Water and PET Without Attenuation Correction

“…Several recent studies have stressed the added value of combined quantitative myocardial blood flow (MBF) and coronary flow reserve (CFR) measurements over qualitative myocardial perfusion imaging (1)(2)(3)(4)(5). The introduction of integrated PET/CT systems, equipped with a CT scanner of at least 64 slices, allows for measurements of calcium score, MBF at rest and MBF during pharmacologic stress, and CT coronary angiography in a single scan session, increasing the diagnostic efficiency and patient comfort (1,(5)(6)(7).…”

“…The introduction of integrated PET/CT systems, equipped with a CT scanner of at least 64 slices, allows for measurements of calcium score, MBF at rest and MBF during pharmacologic stress, and CT coronary angiography in a single scan session, increasing the diagnostic efficiency and patient comfort (1,(5)(6)(7). The necessity of an on-site cyclotron for the production of 15 O has been an obstacle for its introduction into routine clinical practice; however, because water is freely diffusible and has no metabolic interactions in tissue, PET using 15 O-water is considered to be the gold standard for noninvasive quantitative measurements of MBF (3,5).…”

“…The generation of quantitative parametric MBF images of diagnostic quality has long been hampered by poor count statistics of 15 Owater scans acquired using PET scanners with interplane septa. Improved sensitivity of the latest generation of PET/ CT scanners, however, results in better statistics and considerably better image quality, allowing for the generation of high-quality MBF images, even when using only 370 MBq of 15 O-water (5,22).…”