Radionuclide angiography RNA n Gated equilibrium method Eq

Radionuclide angiography (RNA) n Gated equilibrium method (Eq. RNA) n First-pass method (FPRNA)

Gated equilibrium method (Eq. RNA) n Tc-99 m labeled RBCs: in vivo, in vitro, and modified in vivo approach n Tc-99 m human serum albumin

Comparison of First-pass & Gated perfusion methods for evaluation of ventricular function n n First-pass ¨ Needs 99 m. Tc based agents as compact bolus injection ¨ Needs high sensitivity detectors, programs ¨ May be performed with rest and stress ¨ LV & RV wall motion, volumes, and ejection fraction Gated ¨ May be performed with 201 Tl or 99 m. Tc based agents ¨ Uses conventional cameras ¨ May be performed with rest and stress ¨ Only LV wall motion, volumes, and ejection fraction ¨ Provides LV wall thickening ¨ Accuracy dependent on endothelial border definition

Dosimetry for Tc-99 m Red Blood Cells Organ Blood Liver Spleen Bladder Wall Testes Ovaries Heaart Wall Total Body Tc-99 m Red Blood Cells rad/m. Ci 0. 04 0. 03 0. 11 0. 02 0. 01 0. 02 0. 10 0. 015

Drug interfering with Tc-99 m RBC labeling Drug Mechanisms Heparin Formation of labeled heparin Methyldopa, hydralazine Oxidation of stannous ion Digoxin, prazosin, propranolol unknown Iodinated contrast media Competitionn with anion transport system

First-pass method (FPRNA) n Tc-99 m pertechnetate n Tc-99 m DTPA or Tc-99 m sulfur colloid n Short-lived agents: Au-195 m, Ir-191 m, Ta-178

Infarction-avid imaging n Radiopharmaceuticals: Tc-99 m Pyrophosphate, 20 m. Ci, i. v. n Time of imaging: 3 -4 hours after injection