Quantification of Regional Myocardial Blood Flow Using First-Pass Multidetector-Row Computed Tomography and Adenosine Triphosphate in Coronary Artery Disease

Abstract

lectrocardiography (ECG)-gated multidetector-rowcomputed tomography (MDCT) has developed remarkably in the past several years, with improvements in spatial and temporal resolution. [1][2][3] Several studies have focused on its usefulness for assessing the coronary artery lumen, and others studies have demonstrated its capability to evaluate coronary plaques, so the technique has gained acceptance as a valuable tool for coronary imaging in the clinical setting. [4][5][6][7][8][9][10][11] Because of the retrospective acquisition, the same data acquired for coronary computed tomography (CT) imaging can also be reconstructed over a cardiac cycle, allowing dynamic cardiac imaging; and we recently reported that wall motion and systolic thickening could be accurately estimated as functional parameters. 12-14 ECG-gated MDCT technology can therefore evaluate cardiac blood flow from virtually any perspective, including important angles for the interventional approach and for myocardial perfusion.Of these potential applications of cardiac MDCT, myocardial perfusion has so far been less investigated, but its assessment is important for the diagnosis of ischemia and infarction, and for the therapeutic strategy and follow-up. An evaluation of myocardial blood flow (MBF) is also important for studying the pathophysiology of the disease process. A few studies have reported the utility of cardiac MDCT to qualitatively assess myocardial perfusion using a late-enhancement protocol and the adenosine triphosphate (ATP) load technique, [15][16][17][18][19] but quantitative evaluation studies have not been carried out.Therefore, in this study, we investigated the feasibility of cardiac MDCT technology for quantitative assessment of MBF using the ATP-load technique. Methods PatientsFrom April 2006 to May 2007, taking the exclusion criteria into account, 14 patients (11 men, 3 women, age range 52-79 years, mean 69.2 years) underwent ATP-provocation contrast enhanced MDCT, stress thallium-201 myocardial perfusion scintigraphy (MPS), and conventional coronary angiography (CAG). The entry criteria were: (i) de novo effort or rest angina (documented ST-T change on ECG, or relieved by administration of nitroglycerin); (ii) no history of CAG; and (iii) asymptomatic patients with a high probability of coronary artery disease (CAD) (ie, multiple coronary risk factors) or abnormal findings on stress ECG and single-photon emission computed tomography (SPECT). The ATP-load cardiac CT and CAG had an average 40-day interval, and the ATP-load cardiac CT and MPS inspection had an average interval of 29.2 days. Patient characteristics are shown in Table 1. No patient had a history of previous myocardial infarction (MI) and there were no significant differences between men and women in age, clinical symptoms and coronary risk factors.Circ J 2008; 72: 1086 -1091 (Received November 21, 2007; revised manuscript received February 5, 2008; accepted February 7, 2008

Cardiac purinergic signalling in health and disease

“…Affected coronaries fail to dilate properly resulting in a coronary steal phenomenon, manifested as a non-homogenous increase in coronary blood flow, which is reflected in the non-homogeneous distribution of the radio-isotope that can be mapped using a gamma-camera. Adenosine and ATP, and more recently a selective A2AR agonist (Lexiscan [458]), have been used as pharmacologic stressors in this setting [746][747][748][749][750][751][752][753][754]. The use of adenosine-cardiac magnetic resonance imaging for the detection of CAD has been recommended recently [755][756][757].…”

Detection of Myocardial Ischemia Using 64-Slice MDCT

“…[7][8][9] The first-pass imaging of MDCT using pharmacological stress has recently been used to assess myocardial perfusion quantitatively; however, detection of myocardial ischemia at rest using cardiac computed tomography (CT) alone has yet to be elucidated. [10][11][12] This is the purpose of the present study.…”

Cardiac CT for myocardial ischaemia detection and characterization—comparative analysis

“…Although early results of dynamic myocardial perfusion CT (DMP CT ) were demonstrated on a 16-slice scanner, 95 adequate volume coverage is considered a major factor for clinical feasibility of DMP CT . On 320-slice CT-scanner systems, the detector coverage makes dynamic imaging of the heart possible without table movement.…”