Thallium gated SPECT: relation between immediate post-stress evolution of ejection fraction and severity of perfusion pattern

Abstract

Good agreement exists between the severity of ischaemic perfusion pattern and LVEF degradation at stress, which is consistent with previously published data using 99Tc(m) gSPECT. Additionally, the use of 201Tl for immediate post-exercise imaging allows the observation of a physiological LVEF increase in normal and infarcted patients.

Myocardial Stunning During Gated Spect Indicates Presence of Severe Coronary Artery Disease. Biswas,G.** Shukkur, A.M.* Sayed, M.** Alsayed, Y.** and Masoud, M.** Department of Nuclear Medicine **and Cardiology*, Chest Hospital, Kuwait.

“…The results of some studies using imaging modalities that diagnose ischemia on the basis of transient development of regional wall motion abnormalities or fall in global LVEF suggest that ischemic LV dysfunction manifested by global depression of LV function resolves rapidly, whereas the results of other studies indicate that regional LV dysfunction may persist [1] . Good agreement exists between the severity of ischemic perfusion pattern and LVEF degradation at stress, which is consistent with previously published data using Tc99 (m) GSPECT [2] . Post exercise wall motion abnormality (WMA) in patients with normal resting myocardial perfusion may represent prolonged post ischemic stunning, and may be related to the presence of severe angiographically confirmed coronary artery disease (CAD).…”

Evaluation of post-stress left ventricular dysfunction and its relationship with perfusion abnormalities using gated SPECT in patients with cardiac syndrome X

“…Gated SPECT (G-SPECT) offers the potential advantage of combining information about myocardial function and perfusion without any extra cost, any discomfort and radiation risk to the patient [19][20][21][22][23][24]. In addition to the several previous studies, prolonged left ventricular dysfunction (WM abnormalities, LVEF and volume impairments) in post-stress G-SPECT images had been well correlated with myocardial perfusion abnormalities and degree of stenotic vessels in CAG in patients with coronary artery disease [25][26][27][28][29][30][31][32][33][34][35][36]. There are many studies in the literature that showed perfusion abnormalities in cardiac syndrome X patients using myocardial perfusion SPECT [5,6,[37][38][39][40].…”

Usefulness of gated SPECT myocardial imaging in evaluation of patients with inferior myocardial infarction

“…It has been suggested that the decrease in stress EF depends on reversibility of perfusion defect since patients with incomplete reversible ischemia show more impaired contractility [20]. Due to an imbalance between myocardial needs and supplies, perfusion changes are first seen followed by degradation of contraction.…”

“…In addition, we detected a significant decrease in post-stress EF to rest ([5%) in 12 of 77 (16%) patients with IMI, indicating myocardial stunning. The reported incidence of post-ischemic dysfunction ranges from 26 to 57% [6,16,[19][20][21]. These studies differ in patient selection criteria, study protocols, and definitions of myocardial stunning.…”