Ischaemic related transitory left ventricular dysfunction in 201Tl gated SPECT.

AIM: To report our data concerning the changes in post-stress and at-rest left ventricular ejection fraction and ventricular volumes in patients with thallium gated SPECT. METHODS: Post-stress and at-rest thallium gated SPECT was performed in 629 consecutive patients; left ventricular ejection fraction (LVEF), left ventricular volumes and quantitative perfusion data were obtained. Transitory left ventricular dysfunction was diagnosed when post-stress LVEF did not increase at least 5% from LVEF at-rest. RESULTS: In all patients post-stress LVEF was 64%+/-17 while at-rest LVEF was 66%+/-15 (P=0.6). Post-stress end diastolic volume (EDV) was 142 ml+/-7, at-rest EDV was 141 ml+/-92 (P=0.57), post-stress end systolic volume (ESV) was 54 ml+/-51 and at-rest ESV was 56 ml+/-59 (P=0.38). Data from the perfusion study were used to divide patients into three groups: normal patients (group I), patients with total or partially reversible defects (group II) and patients with fixed defects (group III). In group I and group III patients LVEF at-rest was lower than post-exercise (LVEF 75%+/-11 vs 81%+/-10 (P<0.001) and 57%+/-16 vs 60%+/-18 (P=0.025)), respectively. Patients in group II had a higher at-rest LVEF than post-exercise (LVEF 66%+/-14 vs 64%+/-16 (P=0.003)). While the left ventriuclar volumes in group I and III patients decreased with exercise, group II patients had increased post-stress ESV. CONCLUSIONS: Post-stress and at-rest LVEF are similar when all patients are considered but significant differences appear when patients are divided according to the results of the perfusion study. Normal and fixed defect patients have increased post-exercise LVEF. Patients with reversible defects have decreased LVEF, which is largely due to an increased ESV. Transitory left ventricular dysfunction is related to the presence of reversibility and may benefit from revascularization.

[Prognostic value of normal myocardial radionuclide scan in patients with positive treadmill test]. / Valor pronóstico de los estudios de perfusión miocárdica con TI-201 normal en pacientes con ergometría positiva.

The purpose of this study was to determine the prognostic value of a normal 201Tl scan in patients with a positive treadmill exercise stress test. We analyzed retrospectively 85 consecutive patients with a positive treadmill exercise test and normal Tl201 scan who were studied for the diagnosis of coronary artery disease from January 1996 to December 2000. The pretest probability of coronary artery disease was intermediate or high in all patients. Seventy-eight patients (89%) were followed up for 2.03 years. Forty patients (51%) were men. Age was 56 years. The cardiac events considered were angina, revascularization, nonfatal myocardial infarction, and cardiac death. During the follow-up period, none of the patients suffered a major cardiac event. Eight patients had episodes of chest pain and one had angor that required revascularization. Patients with an intermediate probability of coronary artery disease before the test and normal myocardial radionuclide scan had a very good prognosis even with a positive treadmill exercise test.