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ABSTRACT: We assessed the value of positron emission tomography to predict long-term outcome in patients with diabetes and ischemic left ventricular (LV) dysfunction. Circumferential profiles of nitrogen-13 ammonia (NH3) and fluorine-18 fluorodeoxyglucose uptakes were obtained in 61 patients who had diabetes and ischemic LV dysfunction. Patient profiles were compared with those from a normal database. NH3 and fluorine-18 fluorodeoxyglucose defect sizes and extent of perfusion-metabolism mismatch (percentage of myocardium with fluorine-18 fluorodeoxyglucose uptake minus NH3 uptake >2 SD above the normal difference) were determined. Patients were followed every 6 months. Over a mean follow-up of 4.3 years, cardiac death occurred in 52% of patients who underwent revascularization and 61% of those who underwent medical therapy (p = 0.69). No clinical or imaging variables predicted cardiac death in patients who underwent revascularization. In those who received medical therapy, mismatch in > or =3% of the left ventricle (risk ratio 4.0, p = 0.01) was the only multivariate predictor of cardiac death. Revascularization improved survival of patients who had mismatch of > or =3% at 4 years (p = 0.003) and at 8 years (p = 0.012) of follow-up. Patients who had mismatch > or =3% and ejection fraction <30% had the greatest improvement in survival with revascularization compared with medical therapy (p <0.0001). Revascularization also improved 4-year survival of patients who had NH3 perfusion defects of > or =25% of the left ventricle (p = 0.02). In conclusion, mismatch identifies medically treated patients who have diabetes and LV dysfunction, who are at high risk for cardiac death. Intermediate- and long-term survival of patients who have diabetes and mismatch may be improved with revascularization, and those who have significant mismatch and severe LV dysfunction have the greatest benefit.
The American Journal of Cardiology 07/2005; 96(1):2-8. · 3.37 Impact Factor
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ABSTRACT: Tissue Doppler imaging (TDI) patterns from the left atrial appendage (LAA) were evaluated by transesophageal echocardiography. Reproducible, characteristic triphasic or biphasic tissue velocities similar to Doppler flow of the LAA were obtained. Patient peak TDI velocities correlated well with flow and were measurable in atrial fibrillation. Patients with an embolic cerebrovascular accident and in sinus rhythm had higher tissue TDI velocities from the LAA compared with patients without an event, and the groups had similar flow velocities. Hence, Doppler tissue contraction dynamics determined by TDI may complement flow velocities in evaluating LAA function for risk assessment of thromboembolism.
The American Journal of Cardiology 05/2005; 95(8):1011-4. · 3.37 Impact Factor
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Stephen G Sawada,
Stephen J Lewis, Judy Foltz,
Agota Ando,
Samer Khouri,
Shawn Kaser,
Irmina Gradus-Pizlo,
William Gill,
Naomi Fineberg,
Douglas Segar,
Harvey Feigenbaum
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ABSTRACT: This study examined the value of wall motion scores at rest and with low- and high-dose dobutamine infusion for prediction of outcome and benefit from revascularization in patients with ischemic cardiomyopathy. Follow-up was obtained in 139 patients with ischemic cardiomyopathy who had echocardiography at rest, and during low- (10 microg/kg/min) and high-dose dobutamine (maximal dose 50 microg/kg/min) infusion. Both rest and low-dose wall motion scores were multivariate predictors of cardiac death, but ischemia and peak dose scores were not predictors. Rest scores risk stratified patients into 3 groups: score (1.00 to 1.99) with 11% cardiac death; score (2.00 to 2.49) with 30% death; and score > or =2.50 with 47% death. One third of patients with rest scores > or =2.50 had improvement in scores to < 2.50 with low-dose dobutamine. Their frequency of cardiac death was reduced to 23% compared with 60% (p = 0.04) in those who remained with low-dose scores > or =2.50. Low-dose scores also identified those who benefited from revascularization. In patients with low-dose scores (1.00 to 1.99), the frequency of cardiac death was marginally lower in revascularized than nonrevascularized patients (10% vs 21%, p = 0.28). In patients with scores (2.00 to 2.49), revascularized patients had a significantly lower frequency of cardiac death than nonrevascularized patients (15% vs 41%, p < 0.05). The frequency of death in those with low-dose scores > or =2.50 was very high in both revascularized (75%) and nonrevascularized (56%, p = 0.42) patients. Thus, rest and low-dose wall motion scores enable risk stratification of patients with ischemic cardiomyopathy and identify those who do and do not benefit from revascularization.
The American Journal of Cardiology 04/2002; 89(7):811-6. · 3.37 Impact Factor
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ABSTRACT: Positron emission tomography (PET) is considered the gold standard for detecting myocardial viability. Unfortunately, PET is limited by availability and cost. Dobutamine echocardiography (DE) may be a cost effective and more available method of detecting viability. This report compared DE with PET in 33 patients (pts) with advanced coronary disease using a 16 segment model for left ventricular wall motion and uptake of fluorodeoxyglucose (FDG). PET viability was defined as normal or mildly reduced uptake of FDG. DE viability was defined as preserved wall motion at rest or augmentation during DE. PET showed evidence of viability in 93% (157/169) of segments with normal rest wall motion, 85% (62/73) of mildly hypokinetic segments and 93% (68/73) of severely hypokinetic segments. DE and PET were concordant in only 41% (71/175) of akinetic segments (46 nonviable and 25 viable). To investigate this discordance we evaluated follow up echocardiograms (≥four weeks) after coronary bypass surgery in 8 pts with 36 akinetic segments at rest. The ability of PET and DE to predict functional recovery of wall motion is as shown:(+)PV(−)PVSensSpecPET0.440.850.850.44DE0.600.730.460.83PV = predictive valueFull-size tableConclusions1) Normal, mildly hypokinetic or severely hypokinetic rest wall motion on echo correlates strongly with PET evidence of viability. 2) For functional recovery of akinetic segments, PET is sensitive but not specific and DE is specific but not sensitive.
Journal of the American College of Cardiology 25(2):125. · 14.16 Impact Factor
