Diagnostic value of low dose Dobutamine gated SPECT in detection of myocardial viability and short-term prognosis following CABG in heart failure patients

Abstract

Ischemic heart disease is the main cause of mortality and morbidity and high economical costs. In patients with significant amount of viable myocardium muscle after MI, function of LV may recover considereably, because it has been proved that in patients with ischemic cardiomyopathy, systolic dysfunction of LV can be result of repetitive myocardial stunning or myocardial hybernation that can be restored by revascularization in contrast with condition in necrosis of myocardium. The main goal in these patients is prognosis of improvement of LV function. Viable myocardium can improve its function by factors that help myocardium to contract and Dobutamine in low doses has been proved as a prognostic factor of reserved function in patients with chronic coronary artery diseases. Goals: The main goal is Study of diagnostic value of myocardial viability using gated SPECT scan during infusion of low dose Dobutamine compared with detection of myocardial viability with TNG scan in determining short-term prognosis of heart failure patients are candidates for CABG. Material and Methods: 20 patients with past medical history of myocardial infarction that had the inclusion criteria are invited to the study. Patients scanned by gated SPECT and second scan during LDDGS in rest phase Then viable myocardium and scar assessed and compared Also before and 40 days after CABG echocardiography performed and recovery of EF was assessed Difference between TNG and LDDGS observed and diagnostic value of LDDGS scan in recovery of LVEF after revascularization reported. Results: There were no difference between LDDGS and rest TNG scan in assessing the viable myocardium and recovery of EF after 40 days post CABG data. EF after CABG recovered significantly and also diastolic function improved. Survival score also improved.