Application of Appropriateness Criteria to Stress Single-Photon Emission Computed Tomography Sestamibi Studies and Stress Echocardiograms in an Academic Medical Center

ObjectivesThe purpose of this study was to apply published appropriateness criteria for single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in a single academic medical center.BackgroundThe American College of Cardiology Foundation (ACCF) and the American Society of Nuclear Cardiology (ASNC) have developed appropriateness criteria for stress SPECT MPI to address concern about the growth in cardiac imaging studies.MethodsWe retrospectively examined 284 patients who underwent stress SPECT MPI and 298 patients who underwent stress echocardiography before publication of these criteria.ResultsThe overall level of agreement in characterizing appropriateness between 2 experienced cardiovascular nurse abstractors was modest (kappa = 0.56), but noticeably poorer (kappa = 0.27) for patients with previous SPECT or echo studies. Similar percentages of each imaging modality were assigned to the 3 appropriateness categories: 64% of stress SPECT and 64% of stress echo studies were classified appropriate; 11% of stress SPECT and 9% of stress echo were of uncertain appropriateness; and 14% of stress SPECT and 18% of stress echo were inappropriate. Of the inappropriate studies, 88% were performed for 1 of 4 indications. Approximately 10% of the patients were unclassifiable.ConclusionsApplication of existing SPECT MPI appropriateness criteria is demanding and requires an established database or detailed data collection, as well as a number of assumptions. Fourteen percent of stress SPECT studies and 18% of stress echo studies were performed for inappropriate reasons. Quality improvement efforts directed at reducing the number of these inappropriate studies may improve efficiency in the health care system

Recurrent Superior Labral Anterior-to-Posterior Tears after Surgery: Detection and Grading with CT Arthrography

Purpose:To retrospectively evaluate the sensitivity and specificity of multidetector computed tomographic (CT) arthrography for the detection of recurrent superior labral anterior-toposterior (SLAP) tears in the shoulder of patients who have previously undergone shoulder surgery and are clinically suspected of having a recurrent tear. Materials and Methods: The hospital ethics board did not require patient approval or informed consent for this retrospective review of case records. Multidetector CT arthrograms of 45 shoulders of 45 patients (35 men, 10 women; mean age, 29 years; age range, 21–38 years) who had undergone conventional arthroscopy within 30 days after the CT arthrographic examination were reviewed. Owing to the referral patterns at the authors’ institution, all patients were professional athletes. Volumetric multidetector CT arthrography was performed by using a 16-detector CT scanner after the intraarticular injection of iodinated contrast material. All images were independently reviewed by two experienced musculoskeletal radiologists, with disagreements resolved by a third experienced musculoskeletal radiologist. The sensitivity and specificity of multidetector CT arthrography in the detection of any Snyder type II–IV tear was evaluated by using arthroscopy as the reference standard. The numbers and percentages of tears that were assigned the correct Snyder classification with multidetector CT arthrography were reported. Interobserver agreement regarding the correct Snyder classification with multidetector CT arthrography was determined by using statistics. Results: With multidetector CT arthrography, recurrent SLAP tears were correctly identified in 35 of 37 patients (95% sensitivity), and the absence of these tears was correctly noted in seven of eight patients (88% specificity). Multidetector CT arthrography– and arthroscopy-derived tear grades were in agreement in 30 (81%) of 37 patients with recurrent SLAP tears. Interobserver agreement at multidetector CT arthrography was substantial ( 0.76). Conclusion: In the described highly selected patient population, multidetector CT arthrography was useful for evaluating recurrent SLAP tears

Aortic valve area calculation in aortic stenosis by CT and Doppler echocardiography

Objectives The aim of this study was to verify the hypothesis that multidetector computed tomography (MDCT) is superior to echocardiography for measuring the left ventricular outflow tract (LVOT) and calculating the aortic valve area (AVA) with regard to hemodynamic correlations and survival outcome prediction after a diagnosis of aortic stenosis (AS). Background MDCT demonstrated that the LVOT is noncircular, casting doubt on the AVA measurement by 2-dimensional (2D) echocardiography. Methods A total of 269 patients (76 ± 11 years of age, 61% men) with isolated calcific AS (mean gradient 44 ± 18 mm Hg; ejection fraction 58 ± 15%) underwent Doppler echocardiography and MDCT within the same episode of care. AVA was calculated by echocardiography (AVAEcho) and by MDCT (AVACT) using each technique measurement of LVOT area. In the subset of patients undergoing dynamic 4-dimensional MDCT (n = 135), AVA was calculated with the LVOT measured at 70% and 20% of the R-R interval and measured by planimetry (AVAPlani). Results Phasic measurements of the LVOT by MDCT yielded slight differences in eccentricity and size (all p < 0.001) but with excellent AVA correlation (r = 0.92, p < 0.0001) and minimal bias (0.05 cm2), whereas the AVAPlani showed poor correlations with all other methods (all r values <0.58). AVACT was larger than AVAEcho (difference 0.12 ± 0.16 cm2; p < 0.0001) but did not improve outcome prediction. Correlation gradient-AVA was slightly better with AVAEcho than AVACT (r = -0.65 with AVAEcho vs. -0.61 with AVACT; p = 0.01), and discordant gradient-AVA was not reduced. For long-term survival, after multivariable adjustment, AVAEcho or AVACT were independently predictive (hazard ratio [HR]: 1.26, 95% confidence interval [CI]: 1.13 to 1.42; p < 0.0001 or HR: 1.18, 95% CI: 1.09 to 1.29 per 0.10 cm2 decrease; p < 0.0001) with a similar prognostic value (p = 0.80). Thresholds for excess mortality differed between methods: AVAEcho =1.0 cm2 (HR: 4.67, 95% CI: 2.22 to 10.50; p < 0.0001) versus AVACT =1.2 cm2 (HR: 3.16, 95% CI: 1.64 to 6.43; p = 0.005), with simple translation of spline-curve analysis. Conclusions Head-to-head comparison of MDCT and Doppler echocardiography refutes the hypothesis of MDCT superiority for AVA calculation. AVACT is larger than AVAEcho but does not improve the correlation with transvalvular gradient, the concordance gradient-AVA, or mortality prediction compared with AVAEcho. Larger cut-point values should be used for severe AS if AVACT (<1.2 cm2) is measured versus AVAEcho (<1.0 cm2)