title: Preoperative comparison of different noninvasive strategies for predicting improvement in left ventricular function after coronary artery bypass grafting.
abstract: Thallium-201 (Tl-201) imaging and dobutamine stress echocardiography (DSE) are the most frequently used tests in the clinical setting for assessing viability. However, Tl-201 has a suboptimal specificity and DSE a suboptimal sensitivity to predict functional improvement after revascularization. F18-fluorodeoxyglucose (FDG) imaging is considered highly accurate, but availability is limited. Sequential imaging of Tl-201 and DSE may improve accuracy for assessing viability and may be comparable to FDG. Forty-seven patients with ischemic cardiomyopathy underwent Tl-201 single-photon emission computed tomography (SPECT) at rest (4-hour delayed imaging), DSE, and FDG SPECT before bypass surgery. Sensitivity, specificity, and accuracy of 2 sequential strategies were compared with those of FDG SPECT. Strategy 1 considered Tl-201 imaging as the first step, followed by DSE in patients with an intermediate likelihood of viability on Tl-201. Strategy 2 considered DSE as the first step, followed by Tl-201 imaging. Left ventricular ejection fraction was assessed before and 6 months after revascularization, and improvement of >/=5% was considered significant. Tl-201 had a high sensitivity (95%, p <0.05 vs DSE) with a low specificity (57%, p <0.05 vs DSE). DSE had a low sensitivity (63%, p <0.05 vs Tl-201) with a high specificity (89%, p <0.05 vs Tl-201). Both strategies 1 and 2 resulted in high sensitivities (89% and 89%, respectively) and high specificities (89% and 86%, respectively), compared with FDG SPECT (sensitivity 89%, specificity 86%). Sequential testing by Tl-201 SPECT and DSE has a comparable accuracy to FDG SPECT to predict improvement in left ventricular ejection fraction after revascularization. In centers without access to FDG, sequential imaging with Tl-201 and DSE offers an accurate alternative for assessing myocardial viability.
authors.affiliation: Department of Cardiology, University Hospital Leiden, Leiden, The Netherlands. jbax@knoware.nl
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: Bax
authors.forename: Jamshid
authors.initials: J
authors.lastname: Maddahi
authors.forename: Don
authors.initials: D
authors.lastname: Poldermans
authors.forename: Abdou
authors.initials: A
authors.lastname: Elhendy
authors.forename: Arend
authors.initials: A
authors.lastname: Schinkel
authors.forename: Eric
authors.initials: E
authors.lastname: Boersma
authors.forename: Roelf
authors.initials: R
authors.lastname: Valkema
authors.forename: Eric P
authors.initials: EP
authors.lastname: Krenning
authors.forename: Jos R T C
authors.initials: JR
authors.lastname: Roelandt
authors.forename: Ernst E
authors.initials: EE
authors.lastname: van der Wall
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass; D025401:Echocardiography, Stress; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011237:Predictive Value of Tests; D015635:Radionuclide Ventriculography; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000000981:diagnostic imaging
chemical_list: D019275:Radiopharmaceuticals; D013794:Thallium Radioisotopes; D019788:Fluorodeoxyglucose F18