Usefulness of dobutamine Tc-99m sestamibi-gated single-photon emission computed tomography for prediction of left ventricular ejection fraction outcome after coronary revascularization for ischemic cardiomyopathy

Abstract

Gated single-photon emission computed tomography (SPECT) imaging allows analysis of myocardial perfusion and assessment of baseline global and regional left ventricular (LV) function and their changes during lowdose dobutamine infusion. The study examined whether the changes in LV ejection fraction induced by dobutamine and evaluated using technetium-99m sestamibigated SPECT predict the evolution of ejection fraction after revascularization in patients with ischemic cardiomyopathy. Thirty-seven patients underwent resting and dobutamine nitrate-enhanced sestamibi-gated SPECT before revascularization and baseline-resting sestamibi gated SPECT after intervention to assess global functional changes. A postrevascularization improvement in ejection fraction >5 U was defined as significant. At follow-up, ejection fraction increased significantly in 19 patients. According to receiver-operating characteristic curve analysis, an increase in ejection fraction >5 U during dobutamine was the optimal cutoff value for predicting a significant postrevascularization improvement, with 79% sensitivity, 78% specificity, and 78% accuracy. A significant correlation was found between dobutamine and postrevascularization ejection fraction (r ‫؍‬ 0.85; p <0.0001). The increase in ejection fraction during dobutamine is a good predictor of an improvement in ejection fraction after revascularization. This represents another important diagnostic contribution obtained using gated SPECT imaging for the assessment of myocardial viability in patients with ischemic cardiomyopathy. ᮊ2002 by Excerpta Medica, Inc.(Am J Cardiol 2002;89:817-821) T he acquisition of perfusion images using gated single-photon emission computed tomography (SPECT) allows the assessment of regional and global left ventricular (LV) function.1 These additional data are useful in detecting myocardial viability.2-4 Moreover, the acquisition of gated SPECT images during low-dose dobutamine infusion permits assessment of the regional contractile reserve of asynergic segments.5-8 On the other hand, using gated SPECT, LV volumes and ejection fraction can be estimated in a reliable and reproducible way.1 Thus, this study examines whether the changes in LV ejection fraction during dobutamine stimulation, evaluated using technetium-99m sestamibi-gated SPECT, predict changes in ejection fraction after revascularization in patients with ischemic cardiomyopathy. METHODSPatient group: We prospectively evaluated 63 consecutive patients (57 men, mean age 65 Ϯ 9) with coronary artery disease and impaired LV function (mean LV ejection fraction 32 Ϯ 9%, range 9% to 49%) referred to our laboratory for viability assessment using dobutamine nitrate-enhanced gated sestamibi SPECT. Patients with recent (Ͻ1 month) myocardial infarction or unstable angina, heart disease other than coronary artery disease, atrial fibrillation, or history of sustained ventricular tachycardia were excluded. Of this group, 37 patients (33 men, mean age 63 Ϯ 9) who underwent complete myocardial revascularization (14 wit...

The expanding role of left ventricular functional assessment using gated myocardial perfusion SPECT: the supporting actor is stealing the scene

“…The reaction to low-dose dobutamine can be predictive of the left ventricular functional response to revascularisation. Our group observed that an ejection fraction increase by ≥5 units during dobutamine predicted an increase of ≥5 units after revascularisation with an accuracy of 77%, a positive predictive value of 73% and a negative predictive value of 81% [111]. In patients with recent-onset idiopathic dilated cardiomyopathy, Kasama et al demonstrated that the ejection fraction changes induced by low-dose dobutamine and evaluated using gated SPECT were predictive of spontaneous improvement at 1-year follow-up [112].…”

Detection of hibernate myocardium by 99mTc sestamibi gated SPECT during low-dose dobutamine infusion plus nitrate in patients with first acute myocardial infarction

“…Recently, the simultaneous assessment of myocardial cellular integrity using perfusion imaging and of contractile reserve using dobutamine gated SPECT has been suggested as a new approach to viability detection [18][19][20][21]. Various studies demonstrated that the combination of perfusion quantification and contractile reserve evaluation achieved results that were significantly superior to perfusion or contractile reserve data applied separately.…”

“…99m Tc sestamibi gated SPECT is a novel and interesting method for identifying myocardial viability because, in a single stress study, it can provide information about the degree of regional asynergy, segmental tracer uptake, and regional contractile reserve, obviating the need for separate tests to assess reversible dysfunction. The addition of functional data to stress and rest perfusion images significantly improves their specificity and reduces the uncertainty in test interpretation, with a better separation of normal from abnormal studies [18][19][20][21].…”

Technetium‐99m‐labelled HL91 and technetium‐99m‐labelled MIBI SPECT imaging for the detection of ischaemic viable myocardium: a preliminary study

“…, 1995), regional wall contraction by low‐dose dobutamine echography, gated SPECT and MRI (Qureshi et al. , 1997a,b; Leoncini et al. , 2002), regional or global perfusion and functional recovery, etc (Tillisch et al.…”

“…Currently, there have been a variety of end-points proposed for detecting the viability, including myocardium metabolism (Di Carli et al, 1994), biopsy followed by histological examination (Zimmermann et al, 1995), regional wall contraction by low-dose dobutamine echography, gated SPECT and MRI (Qureshi et al, 1997a,b;Leoncini et al, 2002), regional or global perfusion and functional recovery, etc (Tillisch et al, 1986;vom-Dahl et al, 1994;Udelson et al, 1994;Tamaki et al, 1995). From the clinical point of view, the improved perfusion and function following revascularization are optimal endpoints in viability studies, because these have been considered as the main goals of revascularization.…”