shu-508 and technetium-tc-99m-tetrofosmin

The value of stress harmonic power Doppler imaging (HPDI) for the evaluation of myocardial perfusion has never been assessed in patients after acute coronary syndrome (ACS).. To evaluate the agreement between stress HPDI and single photon emission computed tomography (SPECT) imaging for the assessment of myocardial perfusion after unstable angina or myocardial infarction.. Thirty patients with a recent ACS underwent HPDI and SPECT. Images were obtained at rest and during dipyridamole infusion (0.56 mg/kg over 4 min). Apical two- and four-chamber views were used for HPDI. Ten myocardial segments were scored for myocardial perfusion. Semiquantitative and quantitative video intensity analysis with background subtraction were performed.. Concordance by patients between quantitative HPDI and SPECT was 76% (kappa=0.40, Phi=0.46) for normal versus abnormal perfusion. When semiquantitative analysis was used, concordance was 72% (kappa=0.42, Phi=0.46). Agreement between methods was best in the left anterior descending artery territory for quantitative (80%) (kappa=0.60, Phi=0.60) and semiquantitative analysis (78%) (kappa=0.51, Phi=0.60) for normal versus abnormal perfusion. Discrepancies between HPDI and SPECT were most important in the circumflex territory, with a concordance of 59% (kappa=0.22) for identification of normal perfusion versus irreversible and reversible defects.. These results suggest that HPDI can detect myocardial perfusion at rest and during pharmacological stress in patients after a recent ACS. Given the suboptimal agreement with SPECT, further advances are required before the routine use of contrast echocardiography is possible for the assessment of myocardial perfusion.

Topics: Acute Disease; Aged; Aged, 80 and over; Contrast Media; Coronary Circulation; Coronary Disease; Echocardiography; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Polysaccharides; Radiopharmaceuticals; Research Design; Syndrome; Tomography, Emission-Computed, Single-Photon

The aim of the study was to evaluate the accuracy of intermittent, harmonic power Doppler (HPD) during intravenous Levovist infusion in identifying myocardial perfusion abnormalities in patients with recent infarction. Fifty-five patients with first acute myocardial infarction, successfully treated by primary PTCA, were studied after 1 month by myocardial contrast echocardiography (MCE), 99mTc tetrofosmin single photon emission computed tomography (SPECT), and low dose dobutamine echocardiography (DE). Scoring myocardial perfusion as normal, moderately, or severely reduced; MCE and SPECT were in agreement in 71% of segments(k = 0.414). Discordance was mainly due to ventricular walls with normal enhancement by MCE and moderate perfusion abnormalities by SPECT. Scoring perfusion as present or absent, the agreement significantly improved up to 86% (k = 0.59). Sensitivity and specificity of HPD for identifying SPECT perfusion defects were 63% and 93%, respectively. The agreement between MCE and SPECT was higher(85%, k = 0.627)in patients with anterior infarction. An improvement in regional contractile function was noted after dobutamine in 79 dysfunctional segments. A normal perfusion or a moderate perfusion defect by MCE were detected in 71 of 79 of these segments, while a severe perfusion defect was observed in 59 of 85 ventricular segments without dobutamine-induced wall-motion improvement. Sensitivity and specificity by HPD in detecting segments with contractile reserve were 90% and 69%, respectively. Thus, intermittent HPD during Levovist infusion allows myocardial perfusion abnormalities to be detected in patients with recent infarction. This method has a limited sensitivity but a high specificity in detecting SPECT perfusion defects, and a good sensitivity but a limited specificity in detecting contractile reserve.

Topics: Contrast Media; Coronary Circulation; Dobutamine; Echocardiography; Female; Heart; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Polysaccharides; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

To compare the accuracy and feasibility of harmonic power Doppler and digitally subtracted colour coded grey scale imaging for the assessment of perfusion defect severity by single photon emission computed tomography (SPECT) in an unselected group of patients.. Cohort study.. Regional cardiothoracic unit.. 49 patients (mean (SD) age 61 (11) years; 27 women, 22 men) with known or suspected coronary artery disease were studied with simultaneous myocardial contrast echo (MCE) and SPECT after standard dipyridamole stress.. Regional myocardial perfusion by SPECT, performed with (99m)Tc tetrafosmin, scored qualitatively and also quantitated as per cent maximum activity.. Normal perfusion was identified by SPECT in 225 of 270 segments (83%). Contrast echo images were interpretable in 92% of patients. The proportion of normal MCE by grey scale, subtracted, and power Doppler techniques were respectively 76%, 74%, and 88% (p < 0.05) at > 80% of maximum counts, compared with 65%, 69%, and 61% at < 60% of maximum counts. For each technique, specificity was lowest in the lateral wall, although power Doppler was the least affected. Grey scale and subtraction techniques were least accurate in the septal wall, but power Doppler showed particular problems in the apex. On a per patient analysis, the sensitivity was 67%, 75%, and 83% for detection of coronary artery disease using grey scale, colour coded, and power Doppler, respectively, with a significant difference between power Doppler and grey scale only (p < 0.05). Specificity was also the highest for power Doppler, at 55%, but not significantly different from subtracted colour coded images.. Myocardial contrast echo using harmonic power Doppler has greater accuracy than with grey scale imaging and digital subtraction. However, power Doppler appears to be less sensitive for mild perfusion defects.

Topics: Aged; Cohort Studies; Contrast Media; Coronary Disease; Dipyridamole; Echocardiography, Doppler; Echocardiography, Doppler, Color; False Positive Reactions; Feasibility Studies; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Polysaccharides; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon