Assessment of Ischemic Coronary Arteries Prevalence, Reversibility and Relative Dose Ratio% Using 99Mtc- Sestamibi and 201Tl

Abstract

The aim of this study was to assess the ischemic coronary arteries prevalence, reversibility and the relative dose ratio% using 99mTc-Sestamibi and 201TL. The method was adapted from the heart scintigraphy protocol i.e. a sample of one hundred and forty four patients with known or suspected ischemic heart disease (IHD)were administrated to a typically dose of 740 MBq (20 mCi) of 99mTc-MIBI and 74 to 111 MBq (2 to 3 mCi)of 201Tl, Patients under beta-blockers or calcium channel antagonists were asked to discontinue administration for 24 - 48 hours before the stress test, using the slandered Bruce protocol exercise followed by immediate SPECT study for stress ,One to two hours after injection, a rest 201Tl SPECT acquisition was performed, While acquiring rest images for 99mTc-MIBI were obtained two to three hours post stress phase, SPECT acquisition was acquired with 90 degree configuration using contouring centered on the heart. The results analysis was carried out using EXCELL software in form of bars and correlation, which showed that: the male were more common involved by ischemic disease compared to female during the age hood with plateau occurring among age group of 50-70 years old. And the common artery of the heart involved by Ischemia was the left anterior descending artery (LAD) which represented 43% relative to 31% and 26% for LCX and RCA respectively. The reversibility of ischemia in heart arteries were high in case of LAD (43%) and LCX (31%) when detected by 201Tl among male and 99mTc-MIBI among female respectively while RCA shows the less reversibility of ischemia as17% for male by 99mTc-MIBI, 10% for male by 201Tl, 9% for female by 99mTc-MIBI and 11% for female by 201Tl.Also both Tlalium-201 and 99mTc-MIBI can detect the ischemic artery successfully during rest and stress with considerable limited and low exposure dose to other anatomical organs as GIT, Left Lung, and Right Lung.