Radionuclide plethysmography for noninvasive evaluation of peripheral arterial blood flow

Abstract

We validated a noninvasive radionuclide plethysmography technique to evaluate peripheral arterial blood flow during reactive hyperemia. This method, based on the measurement of blood volume variations during repetitive venous occlusions, was compared with strain-gauge venous impedance plethysmography. The technique uses 99m Tc-labeled autologous red blood cells scintigraphy to determine the rate of change of forearm scintigraphic counts during venous occlusion. Thirteen subjects were simultaneously evaluated with radionuclide and impedance plethysmography. Six baseline flow measurements were performed to evaluate the reproducibility of each method. Twenty-seven serial measurements were then made to evaluate flow variation during forearm reactive hyperemia. After 30 min of recovery, resting forearm blood flows were again evaluated. Impedance and radionuclide methods showed excellent reproducibility with intraclass correlation coefficients of 0.96 and 0.93, respectively. There was also good correlation of flows between both methods during reactive hyperemia (r ϭ 0.87). Resting flows at 30 min after reactive hyperemia were slightly lower than at baseline with both methods. We conclude that radionuclide plethysmography could be used for the noninvasive evaluation of forearm blood flow and its dynamic variations during reactive hyperemia. endothelium; radioisotope; reactive hyperemia VENOUS PLETHYSMOGRAPHY OF the arms and legs has been extensively used to evaluate vascular function in normal and diseased states (4,14). With this method, vascular reactivity can be tested by the local infusion of pharmacological agents or by evaluation of hyperemic responses after a brief period of limb ischemia. Although it has been well validated, the use of venous plethysmography for the study of arterial reactivity has been limited to research because specialized equipment is needed and because expertise is not available in most clinical centers.Recently, there has been a growing interest in the clinical evaluation of peripheral vascular reactivity during reactive hyperemia because part of this physiological response is modulated by the integrity of the vascular endothelium (2, 8). Endothelial dysfunction is a diffuse process that occurs early in the development of atherosclerotic vascular disease (7, 9). Evidence shows that evaluation of endothelial function may be useful in risk stratification and in the assessment of response to pharmacological treatment (5). In that context, development of a simple, noninvasive, and reproducible test of the reactive hyperemic response is desirable not only for preclinical and clinical research purposes but also for its potential clinical utility.We have thus developed a noninvasive radionuclide plethysmography technique to evaluate peripheral arterial blood flow during reactive hyperemia. This method, based on the measurement of blood volume variations during repetitive venous occlusion, is analogous to impedance plethysmography (3, 12) and can also evaluate arterial blood flow into arms or leg...

Evaluation of biologic effects of an Ilex paraguariensis aqueous extract on the labeling of blood constituents with technetium-99m and on the morphology of red blood cells

“…These radiopharmaceuticals can be used for important applications, including imaging of cardiovascular system (Niemeyer et al, 1995;Crandall et al, 2008;Javadi et al, 2011), peripheral arterial blood flow (Blond and Madsen, 2000;Harel et al, 2005;Hsieh et al, 2009), evaluation of gastrointestinal bleeding (Zaman et al, 2004;Wong et al, 2004;Olds et al, 2005;Schillaci et al, 2009;Dolezal et al, 2011), measurement of red cell volume (Hladik III et al, 1987), hepatic hemangiomas (Artiko et al, 2004;Verdu et al, 2005;Yarlagadda et al, 2008), renal carcinoma (Cortes et al, 2003), splenic reticuloendothelial system (Jin et al, 2004;Slart et al, 2004) and imaging infection (Stoeckli et al, 1996) Tc to internal structures (Early and Soddee, 1995;Dewanjee et al, 1982). The band-3 anion transport system and calcium channels may be involved in transport of 99m TcO 4 -and Sn…”

Alteration of the labeling of blood constituents with technetium-99m and the morphology of red blood cells by Baccharis trimera extract

“…These radiobiocomplexes can be used for important applications, including imaging of cardiovascular system (Niemeyer et al, 1995), peripheral arterial blood flow (Blond and Madsen, 2000;Harel et al, 2005), evaluation of gastrointestinal bleeding (Wong et al, 2004;Zaman et al, 2004;Olds et al, 2005), measurement of red cell volume (Hladik III et al, 1987), hepatic hemangiomas (Artiko et al, 2004;Verdu et al, 2005), renal carcinoma (Cortes et al, 2003), splenic reticuloendothelial system (Jin et al, 2004;Slart et al, 2004) and imaging infection (Stoeckli et al, 1996). The labeling procedure of blood constituents with 99m Tc has been also considered as an experimental model to evaluate some properties and effects of natural and synthetic products (Oliveira et al, 2003a;Oliveira et al, 2003b;Frydman et al, 2004;Moreno et al, 2004;Fonseca et al, 2005;Bustani et al, 2009 Tc to internal structures (Dewanjee et al, 1982).…”

Effects of clove (Caryophyllus aromaticus L.) on the labeling of blood constituents with technetium-99m and on the morphology of red blood cells

“…Eugenol is known to inhibit the growth of bacteria and is a natural antibiotic (Suresh-Babu and Madhavi, 2001) with broad antimicrobial activities against gram-positive, gram-negative and acid fast bacteria, as well as fungi (Bisset, 1994;Lueng and Foster, 1996). Red blood cells labeled with technetium-99m (99mTc-RBC) are widely used in clinical nuclear medicine for several important applications (Wong et al, 2004;Jin et al, 2004;Zaman et al, 2004;Artiko et al, 2004;Harel et al, 2005;Verdu et al, 2005;Olds et al, 2005). The labeling of RBC with 99mTc has been used as assay to evaluate the properties of different chemical agents (Abreu et al, 2006;Fonseca et al, 2007).…”