Noninvasive diagnosis of coronary artery stenosis in women with limited exercise capacity: comparison of dobutamine stress echocardiography and 99mTc sestamibi single-photon emission CT

OBJECTIVES: To compare the accuracy of dobutamine stress echocardiography (DSE) and simultaneous 99mTc sestamibi (MIBI) single-photon emission CT (SPECT) imaging for the diagnosis of coronary artery stenosis in women. PATIENTS: Seventy women with limited exercise capacity referred for evaluation of myocardial ischemia. METHODS: DSE (up to 40 microg/kg/min) was performed in conjunction with stress MIBI SPECT. Resting MIBI images were acquired 24 h after the stress test. Ischemia was defined as new or worsened wall motion abnormalities confirmed by DSE and as reversible perfusion defects confirmed by MIBI. Significant coronary artery disease was defined as > or = 50% luminal diameter stenosis. RESULTS: DSE was positive for ischemia in 35 of 45 patients with coronary artery stenosis and in 2 of 25 patients without coronary artery stenosis (sensitivity = 78% CI, 68 to 88; specificity = 92% CI, 85 to 99; and accuracy = 83% CI, 74 to 92). A positive MIBI study for ischemia occurred in 29 patients with coronary artery stenosis and in 7 patients without coronary artery stenosis (sensitivity = 64% CI, 53 to 76; specificity = 72% CI, 61 to 83; and accuracy = 67% CI, 56 to 78 [p < 0.05 vs DSE]). In the 59 vascular regions with coronary artery stenosis, the regional sensitivity of DSE was higher than MIBI (69% CI, 62 to 77 vs 51% CI, 42 to 59, p < 0.05), whereas specificity in the 81 vascular regions without significant stenosis was similar (89% CI, 84 to 94 vs 88% CI, 82 to 93, respectively). CONCLUSION: DSE is a useful noninvasive method for the diagnosis of coronary artery stenosis in women and provides a higher overall and regional diagnostic accuracy than dobutamine MIBI SPECT in this particular population

Impact of severity of coronary artery stenosis and the collateral circulation on the functional outcome of dyssynergic myocardium after revascularization in patients with healed myocardial infarction and chronic left ventricular dysfunction

The aim of this study was to assess the influence of the severity of coronary artery stenosis and the grade of collateral circulation on myocardial viability in patients with chronic left ventricular (LV) dysfunction undergoing coronary artery bypass grafting. Forty patients (age 59 ± 8 years) with old myocardial infarction were studied by dobutamine stress echocardiogrophy (DSE) before coronary artery bypass grafting. LV function was assessed using a 16-segment, 5-grade score model. Viability and functional recovery were respectively defined as a reduction in wall motion score ≤ 1 at low-dose DSE and at follow-up echocardiograms obtained 3 months after surgery. There were 56 stenotic coronary arteries subtending severely dyssynergic myocardial segments, of which 38 were occluded. Among 186 severely dyssynergic segments, functional recovery occurred in 42 (23%). There was no significant difference between myocardial regions with patent or occluded coronary arteries with respect to prevalence of viability or functional recovery and percentage of viable or recovered segments relative to the total number of dyssynergic segments. In patients with total occlusion, these parameters were not different between regions with different collateral grades. Sensitivity, specificity, and accuracy of low-dose DSE for prediction of regional functional recovery were 71%, 90%, and 86%, r

Gender differences in the accuracy of dobutamine stress echocardiography for the diagnosis of coronary artery disease

The accuracy of dobutamine stress echocardiography (DSE) for the diagnosis of coronary artery disease (CAD) has not been yet evaluated in women. We studied the effect of gender on the accuracy of DSE for the diagnosis of CAD in 306 consecutive patients (210 men and 96 women) with limited exercise capacity and suspected myocardial ischemia who underwent coronary angiography within 3 months of DSE. There were no serious complications during DSE. Men had a higher prevalence of nonsustained ventricular tachycardia (7% vs 0.03%, p <0.05) and supraventricular tachycardia (9% vs 0.03%, p <0.05) during the test compared with women. Peak stress rate-pressure product was not different in men and women (18,140 ± 4,187 vs 18,543 ± 4,223). Significant CAD (≤50% luminal diameter stenosis) was present in 171 men (81%) and in 62 women (65%, p <0.005). The sensitivity, specificity, and accuracy of ischemic pattern at DSE for the diagnosis of significant CAD were 76% (confidence interval [CI] 67 to 84), 94% (CI 89 to 99), and 82% (C175 to 90) in women and 73% (CI 67 to 79), 77% (CI 71 to 83), and 74% (Cl 68 to 80) in men, respectively. Overall specificity was higher in women than in men (p <0.05). Regional accuracy of DSE was significantly higher in women than in men in the 3 arterial regions (84% [CI 79 to 88] vs 75% [CI 72 to 79], p <0.005). It is concluded that DSE is a safe and feasible method for the diagnosis of CAD in women.

Phenotypic and functional characterization of T cells in white matter lesions of multiple sclerosis patients

T cells are considered pivotal in the pathology of multiple sclerosis (MS), but their function and antigen specificity are unknown. To unravel the role of T cells in MS pathology, we performed a comprehensive analysis on T cells recovered from paired blood, cerebrospinal f

Relation between ST segment elevation during dobutamine stress test and myocardial viability after a recent m

OBJECTIVE: To assess the relation between ST segment elevation during the dobutamine stress test and late improvement of function after acute Q wave myocardial infarction. PATIENTS AND DESIGN: 70 patients were studied a mean (SD) 8 (3) days after acute myocardial infarction with high dose dobutamine-atropine stress echocardiography and a follow up echocardiogram at 85 (10) days. A score model based on 16 segments and four grades was used to assess left ventricular function. Functional improvement was defined as a reduction of wall motion score > or = 1 in > or = 1 segments at follow up. INTERVENTION: Myocardial revascularisation was performed in 23 patients (33%) before follow up studies. RESULTS: ST segment elevation occurred in 40 patients (57%). Late functional improvement occurred in 35 patients (50%). Functional improvement was more common in patients with ST segment elevation (68% v 30%, P < 0.005) and they had a higher mean (SD) number of improved segments at follow up (1.9 (2.2) v 0.5 (1.1), P < 0.005). The wall motion score index decreased between baseline and follow up in patients with ST segment elevation (1.54 (0.50) v 1.48 (0.43), P < 0.05) but not in patients without ST segment elevation (1.39 (0.60) v 1.45 (0.47)). The accuracy of ST segment elevation for the prediction of functional improvement was similar to that of low dose dobutamine echocardiography in patients with anterior infarction (80% v 83%) and in patients who underwent revascularisation (78% v 83% respectively). CONCLUSION: In patients with a recent Q wave myocardial infarction, dobutamine-induced ST segment elevation is a valuable marker of myocardial viability particularly when the test is performed without or with suboptimal echocardiographic imaging