USE OF TC-99M SESTAMIBI INFUSION FOR DETECTION OF HIBERNATING MYOCARDIUM - A PRELIMINARY-REPORT

To evaluate whether a prolonged infusion of Tc-99m sestamibi allows fo r visualization of viable myocardium in areas of hypoperfused myocardi um, 25 patients were prospectively studied. Each patient was imaged fo ur times in two consecutive days in the following manner: day 1: 1) im mediately after injection of TI-201 at rest, 2) 1 hour after a bolus i njection of Tc-99m sestamibi at rest; and day 2: 1) imaging in the TI- 201 window for 24 hour redistribution, 2) imaging after a 1-hour infus ion of Tc-99m sestamibi. The two Tc-99m sestamibi and two TI-201 studi es were evaluated for presence of redistribution, This was present bot h on the TI-201 and Tc-99m sestamibi studies (concordant) in 13 cases, and absent on both the TI-201 and Tc-99m sestamibi studies (concordan t) in 9 cases. In two cases redistribution was seen on the TI-201 imag es only, and in one case it was seen on the Tc-99m sestamibi images on ly (discordant). Tc-99m sestamibi infusion may provide information abo ut the presence of viable myocardium which is similar to that provided by TI-201 24-hour imaging.