Thomas J Brady

Publications of Thomas J Brady

• Coronary computed tomography angiography during arrhythmia: Radiation dose reduction with prospectively ECG-triggered axial and retrospectively ECG-gated helical 128-slice dual-source CT.

  Authors: Ashley M Lee, Leif-Christopher Engel, Baiju Shah, Gary Liew, Manavjot S Sidhu, Mannudeep Kalra, Suhny Abbara, Thomas J Brady, Udo Hoffmann, Brian B Ghoshhajra

  Journal of cardiovascular computed tomography. 04/2012;

  BACKGROUND: Arrhythmia during coronary computed tomography angiography (coronary CTA) acquisition increases the risk of nondiagnostic segments and high radiation exposure. An advanced arrhythmiaBACKGROUND: Arrhythmia during coronary computed tomography angiography (coronary CTA) acquisition increases the risk of nondiagnostic segments and high radiation exposure. An advanced arrhythmia rejection algorithm for prospectively electrocardiogram (ECG)-triggered axial scans using dual-source CT (DSCT) examinations has recently been reported. OBJECTIVE: We compared image quality and effective dose at DSCT examinations using prospectively ECG-triggered axial scanning with advanced arrhythmia rejection software (PT-AAR) versus retrospectively ECG-gated helical scanning with tube-current modulation (RG-TCM) during arrhythmia. METHODS: This was a retrospective case-control study of 90 patients (43 PT-AAR, 47 RG-TCM) with arrhythmia (defined as heart rate variability [HRV] > 10 beats/min during data acquisition) referred for physician-supervised coronary CTA between April 2010 and September 2011. A subset of 22 cases matched for body mass index, HR, HRV, and other scan parameters was identified. Subjective image quality (4-point scale) and effective dose (dose length product method) were compared. RESULTS: PT-AAR was associated with lower effective dose than RG-TCM (4.1 vs 12.6 mSv entire cohort and 4.3 vs 9.1 mSv matched controls; both P < 0.01). Image quality scores were excellent in both groups (3.9 PT-AAR vs 3.6 RG-TCM) and nondiagnostic segment rates were low (0.1% vs 0.6%). Significantly higher image quality scores were found with PT-AAR in the entire cohort (P < 0.05), and in matched controls with high HRV > 28 beats/min (P < 0.05). CONCLUSIONS: In patients with variable heart rates, prospectively ECG-triggered axial DSCT with arrhythmia rejection algorithm is feasible and can decrease radiation exposure by ∼50% versus retrospectively ECG-gated helical DSCT, with preserved image quality.

• A Computed Tomography-Based Coronary Lesion Score to Predict Acute Coronary Syndrome Among Patients With Acute Chest Pain and Significant Coronary Stenosis on Coronary Computed Tomographic Angiogram.

  Authors: Maros Ferencik, Christopher L Schlett, Brian B Ghoshhajra, Mathias F Kriegel, Subodh B Joshi, Pal Maurovich-Horvat, Ian S Rogers, Dahlia Banerji, Fabian Bamberg, Quynh A Truong, Thomas J Brady, John T Nagurney, Udo Hoffmann

  The American journal of cardiology. 04/2012;

  We tested the hypothesis that morphologic lesion assessment helps detect acute coronary syndrome (ACS) during index hospitalization in patients with acute chest pain and significant stenosis onWe tested the hypothesis that morphologic lesion assessment helps detect acute coronary syndrome (ACS) during index hospitalization in patients with acute chest pain and significant stenosis on coronary computed tomographic angiogram (CTA). Patients who presented to an emergency department with chest pain but no objective signs of myocardial ischemia (nondiagnostic electrocardiogram and negative initial biomarkers) underwent CT angiography. CTA was analyzed for degree and length of stenosis, plaque area and volume, remodeling index, CT attenuation of plaque, and spotty calcium in all patients with significant stenosis (>50% in diameter) on CTA. ACS during index hospitalization was determined by a panel of 2 physicians blinded to results of CT angiography. For lesion characteristics associated with ACS, we determined cutpoints optimized for diagnostic accuracy and created lesion scores. For each score, we determined the odds ratio (OR) and discriminatory capacity for the prediction of ACS. Of the overall population of 368 patients, 34 had significant stenosis and 21 of those had ACS. Scores A (remodeling index plus spotty calcium: OR 3.5, 95% confidence interval [CI] 1.2 to 10.1, area under curve [AUC] 0.734), B (remodeling index plus spotty calcium plus stenosis length: OR 4.6, 95% CI 1.6 to 13.7, AUC 0.824), and C (remodeling index plus spotty calcium plus stenosis length plus plaque volume <90 HU: OR 3.4, 95% CI 1.5 to 7.9, AUC 0.833) were significantly associated with ACS. In conclusion, in patients presenting with acute chest pain and stenosis on coronary CTA, a CT-based score incorporating morphologic characteristics of coronary lesions had a good discriminatory value for detection of ACS during index hospitalization.

• Comparison of cardiac computed tomography examination appropriateness under the 2010 revised versus the 2006 original Appropriate Use Criteria.

  Authors: Meagan M Wasfy, Thomas J Brady, Suhny Abbara, Khurram Nasir, Udo Hoffmann, Ricardo C Cury, Marcelo F Di Carli, Ron Blankstein

  Journal of cardiovascular computed tomography. 03/2012; 6(2):99-107.

  The 2006 Cardiac CT Appropriate Use Criteria (AUC) were recently revised in 2010. In addition to rating an expanded number of indications, the new criteria adjusted the appropriateness of existingThe 2006 Cardiac CT Appropriate Use Criteria (AUC) were recently revised in 2010. In addition to rating an expanded number of indications, the new criteria adjusted the appropriateness of existing indications to reflect changes in clinical practice and new evidence since 2006. We sought to determine how the appropriateness of cardiac CT examinations performed at a tertiary-care hospital changed under the revised criteria compared with the original AUC. Data were collected from the medical records and personal interview of 267 consecutive patients referred for cardiac CT in 2008. With the use of the 2010 and 2006 AUCs, two physicians designated each examination's indication as appropriate, inappropriate, uncertain, or "not classified" if examination indication could not be assigned. With the use the new 2010 AUC, a highly significant change was observed in the classification of examination appropriateness (P < 0.001), with 40% of examinations changing appropriateness level compared with the 2006 AUC. Under the 2010 AUC, there were an increased proportion of both appropriate examinations (59% vs. 45%; P < 0.001) and inappropriate examinations (15% vs. 10%; P < 0.001), and approximately the same proportion with uncertain appropriateness (13% vs. 16%; P = 0.33). Consequently, the proportion of examinations that were not classified was significantly reduced under the 2010 AUC (29% vs. 13%; P < 0.001). The revision of the AUC for cardiac CT had a significant effect on examination appropriateness. In comparison to the 2006 AUC, the 2010 AUC provided improved clarification of examination appropriateness. This shift was because of the inclusion of many previously unaddressed indications and the designation of more examinations as either appropriate or inappropriate.

• Comparison of Exercise Treadmill Testing With Cardiac Computed Tomography Angiography Among Patients Presenting to the Emergency Room With Chest Pain: The Rule Out Myocardial Infarction Using Computer-Assisted Tomography (ROMICAT) Study.

  Authors: Ron Blankstein, Waleed Ahmed, Fabian Bamberg, Ian S Rogers, Christopher Lothar Schlett, Khurram Nasir, Joao Fontes, Ahmed Tawakol, Thomas J Brady, John T Nagurney, Udo Hoffmann, Quynh A Truong

  Circulation. Cardiovascular imaging. 02/2012; 5(2):233-42.

  Background- The aims of our study were to (1) examine how data from exercise treadmill testing (ETT) can identify patients who have coronary plaque or stenosis, using CT angiography (CTA) as theBackground- The aims of our study were to (1) examine how data from exercise treadmill testing (ETT) can identify patients who have coronary plaque or stenosis, using CT angiography (CTA) as the reference standard, and (2) identify patient characteristics that may be used in selecting ETT versus CTA. Methods and Results- The Rule Out Myocardial Infarction Using Computer-Assisted Tomography (ROMICAT) trial was an observational cohort study of acute chest pain patients presenting to the emergency department with normal initial troponin and a nonischemic ECG. Univariate and multivariable analyses were performed to assess the relationship of baseline clinical data and ETT parameters with coronary plaque and stenosis on CTA. Of the 220 patients who had ETT (mean age, 51 years; 63% men), 21 (10%) had positive results. A positive ETT had a sensitivity of 30% and specificity of 93% to detect >50% stenosis. The sensitivity increased to 83% after excluding uninterpretable segments and evaluating the ability to detect a >70% stenosis. Predictors of plaque included older age, male sex, diabetes, hypertension, hyperlipidemia, lower functional capacity, and a lower Duke Treadmill Score. Both a positive ETT and a low Duke Treadmill Score were significant univariate and multivariable predictors of stenosis >50% on CTA Whereas the prevalence of stenosis by CTA was greater among patients with more risk factors, coronary stenosis was not present among men <40 years old or women <50 years old or individuals who achieved at least 13 metabolic equivalents on ETT. Conclusions- Among low- to intermediate-risk patients with acute chest pain, a positive ETT has a limited sensitivity but high specificity for the detection of >50% stenosis by CTA. Although patients with a high number of clinical risk factors are more likely to have obstructive coronary artery disease, those who are young or who would be expected to have a very high exercise capacity are unlikely to have coronary stenosis and therefore may benefit from initial ETT testing instead of CTA.

• Comparison of the Diamond-Forrester Method and Duke Clinical Score to Predict Obstructive Coronary Artery Disease by Computed Tomographic Angiography.

  Authors: Meagan M Wasfy, Thomas J Brady, Suhny Abbara, Khurram Nasir, Brian B Ghoshhajra, Quynh A Truong, Udo Hoffmann, Marcelo F Di Carli, Ron Blankstein

  The American journal of cardiology. 01/2012;

  We sought to evaluate the ability of the Diamond and Forrester method (DFM) and the Duke Clinical Score (DCS) to predict obstructive coronary artery disease (CAD) on coronary computed tomographicWe sought to evaluate the ability of the Diamond and Forrester method (DFM) and the Duke Clinical Score (DCS) to predict obstructive coronary artery disease (CAD) on coronary computed tomographic angiography (CCTA) and the effect of these different risk scores on the appropriateness level using the 2010 Appropriate Use Criteria. Consecutive symptomatic patients who underwent CCTA for evaluation of CAD (n = 114) were classified as having a low, intermediate, or high pretest probability using the DFM and DCS. Using the Appropriate Use Criteria, the indications for CCTA were classified according to the pretest probability and previous testing. The CCTA results were classified as revealing obstructive (≥70% stenosis), nonobstructive (<70%), or no CAD. When the patients' risk was classified using the DFM, 18% were low, 65% intermediate, and 17% high risk. When using the DCS, 53% of patients had a reclassification of their risk, most of whom changed from intermediate to either low or high risk (50% low, 19% intermediate, 35% high risk). The net reclassification improvement for the prediction of obstructive CAD was 51% (p = 0.01). Of the 37 patients who were reclassified as low risk, 36 (97%) lacked obstructive CAD. Appropriateness for CCTA was reclassified for 13% of patients when using the DCS instead of the DFM, and the number of appropriate examinations was significantly fewer (68% vs 55%, p <0.001). In conclusion, reclassification of risk using the DCS instead of the DFM resulted in improved prediction of obstructive CAD on CCTA, especially in low-risk patients. More patients were categorized as having a high pretest probability of CAD, resulting in reclassification of their examination indications as uncertain or inappropriate. These results identify the need for improved pretest risk scores for noninvasive tests such as CCTA and suggest that the method of risk assessment could have important implications for patient selection and quality assurance programs.

• Distribution of inflammation within carotid atherosclerotic plaques with high-risk morphological features: a comparison between positron emission tomography activity, plaque morphology, and histopathology.

  Authors: Amparo L Figueroa, Sharath S Subramanian, Ricardo C Cury, Quynh A Truong, Joseph A Gardecki, Guillermo J Tearney, Udo Hoffmann, Thomas J Brady, Ahmed Tawakol

  Circulation. Cardiovascular imaging. 01/2012; 5(1):69-77.

  Several high-risk morphological features (HRM) of plaques, especially in combination, are associated with an increased risk of a clinical event. Although plaque inflammation is also associated withSeveral high-risk morphological features (HRM) of plaques, especially in combination, are associated with an increased risk of a clinical event. Although plaque inflammation is also associated with atherothrombosis, the relationship between inflammation and number of HRM is not well understood. Thirty-four patients underwent (18)flurodeoxyglucose positron emission tomography (FDG-PET) imaging, and carotid atherosclerotic inflammation was assessed (target-to- =0.0003) and increased with the number of HRM observed (P<0.001 for trend). Similarly, inflammation within atherosclerotic specimens (% CD68 staining) was higher in plaques with (versus without) HRM (median [interquartile range]: 10 [0, 19.85] versus 0 [0, 1.55], P=0.01) and increased with the number of HRM observed (P<0.001 for trend). Inflammation, as assessed by both FDG uptake and histology, is increased in plaques containing HRM and increases with increasing number of HRM. These data support the concept that inflammation accumulates relative to the burden of morphological abnormalities.

• Comparison of dual-source 64-slice adenosine stress CT perfusion with stress-gated SPECT-MPI for evaluation of left ventricular function and volumes.

  Authors: Shanmugam Uthamalingam, Gagandeep S Gurm, Manavjot S Sidhu, Daniel J Verdini, Yongkasem Vorasettakarnkij, Leif-Christopher Engel, Ron Blankstein, Wilfred S Mamuya, Udo Hoffman, Thomas J Brady, Ricardo C Cury, Brian B Ghoshhajra

  Journal of cardiovascular computed tomography. 01/2012; 6(1):24-30.

  Evaluation of left ventricular (LV) volumes and ejection fraction (LVEF) represent important components of pharmacologic stress imaging with either myocardial CT perfusion (CTP) or gatedEvaluation of left ventricular (LV) volumes and ejection fraction (LVEF) represent important components of pharmacologic stress imaging with either myocardial CT perfusion (CTP) or gated single-photon emission CT (SPECT) myocardial perfusion imaging (SPECT-MPI). We compared measurements of left ventricular function and volumes obtained with CTP and SPECT-MPI. Forty-seven patients (mean age, 62 ± 11 years; male, n = 39) underwent stress CTP and SPECT-MPI. LVEF (in %), end-systolic volume (ESV; in mL), and end-diastolic volume (EDV; in mL) derived from stress CTP images were compared with SPECT-MPI. Stress CTP was in good agreement with SPECT-MPI for quantification of LVEF (r = 0.91), EDV (r = 0.75), and ESV (r = 0.83; all P < 0.001). The mean LVEF measured by stress CTP (66% ± 17%) was similar to SPECT-MPI (64% ± 15%). Similar values were also derived for mean EDV (123 ± 30 mL vs 120 ± 34 mL) and ESV (44 ± 28 mL vs 51 ± 34 mL) for CTP and SPECT-MPI, respectively. Good agreement was also shown between both techniques for the assessment of regional wall motion with identical wall motion scores in 95.3% of the segments (κ = 0.79). LVEF and LV volume parameters as determined by dual-source 64-slice adenosine stress CTP show a high correlation with values obtained with stress-gated SPECT-MPI.

• A decomposition-based CT reconstruction formulation for reducing blooming artifacts.

  Authors: Synho Do, W Clem Karl, Zhuangli Liang, Mannudeep Kalra, Thomas J Brady, Homer H Pien

  Physics in medicine and biology. 11/2011; 56(22):7109-25.

  Cardiac computed tomography represents an important advancement in the ability to assess coronary vessels. The accuracy of these non-invasive imaging studies is limited, however, by the presence ofCardiac computed tomography represents an important advancement in the ability to assess coronary vessels. The accuracy of these non-invasive imaging studies is limited, however, by the presence of calcium, since calcium blooming artifacts lead to an over-estimation of the degree of luminal narrowing. To address this problem, we have developed a unified decomposition-based iterative reconstruction formulation, where different penalty functions are imposed on dense objects (i.e. calcium) and soft tissue. The result is a quantifiable reduction in blooming artifacts without the introduction of new distortions away from the blooming observed in other methods. Results are shown for simulations, phantoms, ex vivo, and in vivo studies.

• Infarct detection with a comprehensive cardiac CT protocol.

  Authors: Brian B Ghoshhajra, Pal Maurovich-Horvat, Tust Techasith, Hector M Medina, Daniel Verdini, Manavjot S Sidhu, Ron Blankstein, Thomas J Brady, Ricardo C Cury

  Journal of cardiovascular computed tomography. 11/2011; 6(1):14-23.

  Cardiac CT has the potential to offer comprehensive infarct detection by assessing regional wall motion abnormalities (RWMAs), rest perfusion defects (RPDs), and delayed contrast enhancement (DCE).Cardiac CT has the potential to offer comprehensive infarct detection by assessing regional wall motion abnormalities (RWMAs), rest perfusion defects (RPDs), and delayed contrast enhancement (DCE). However, the diagnostic accuracy of these techniques for the detection of myocardial infarction (MI) is unknown. Forty-eight patients with intermediate-to-high probability for coronary artery disease after single-photon emitting CT myocardial perfusion imaging were prospectively enrolled for a research comprehensive 64-detector row dual-source cardiac CT protocol that included cine images for RWMA, first-pass images for RPD, and delayed images for DCE. Blinded readers independently assessed each technique. Subsequently, a final combined analysis (cine + rest + DCE) was performed. The universal definition for MI by the 2007 American Heart Association task force was used as the "gold standard." Twenty-four of 48 patients (50%) had infarct by the universal definition. The combined CT analysis was most accurate (90%) with the highest per-patient sensitivity (88%) and specificity (92%) versus individual assessments (RWMA, 79% and 88%; RPD, 67% and 92%; DCE, 79% and 88%). Similar findings were observed on a per-vessel basis analysis. A combination of DCE and cine showed a good accuracy (85%) and high sensitivity (92%). Infarct detection with CT is feasible with overall good diagnostic accuracy compared with the universal definition. A combined evaluation that included all techniques (cine, RPD, and DCE) had the highest diagnostic accuracy. These findings may have implications when designing future clinical and research CT protocols for optimal infarct detection.

• A comparison of reconstruction and viewing parameters on image quality and accuracy of stress myocardial CT perfusion.

  Authors: Brian B Ghoshhajra, Ian S Rogers, Pal Maurovich-Horvat, Tust Techasith, Daniel Verdini, Manavjot S Sidhu, Nicola K Drzezga, Hector M Medina, Ron Blankstein, Thomas J Brady, Ricardo C Cury

  Journal of cardiovascular computed tomography. 11/2011; 5(6):459-66.

  Myocardial stress computed tomography perfusion (CTP) has similar diagnostic accuracy for detecting perfusion defects (PDs) versus single-photon emission computed tomography (SPECT). However, theMyocardial stress computed tomography perfusion (CTP) has similar diagnostic accuracy for detecting perfusion defects (PDs) versus single-photon emission computed tomography (SPECT). However, the optimal diagnostic viewing and image processing parameters for CTP are unknown. We sought to compare the diagnostic accuracy of different image processing techniques, cardiac phases, slice thicknesses, and viewing parameters for detection of PDs. A stress and rest dual-source CTP protocol was performed with adenosine. Twelve subjects with severe stenosis proven by quantitative coronary angiography (QCA), with corresponding territorial defects at SPECT, were selected as well as 7 controls (subjects with similar clinical suspicion but negative QCA and SPECT). Short-axis stress images were processed with 3 techniques: minimum intensity projection (MinIP), maximum intensity projection, and average intensity multiplanar reconstruction (MPR), 3 thicknesses (1, 3, 8 mm), and 2 phases (systolic, mid-diastolic). The resulting images (n = 1026) were randomized and interpreted by independent readers. Diastolic reconstructions (8-mm MPR) showed the highest sensitivity (81%) to detect true PDs. The highest accuracy was achieved with the 8-mm (61%) and 1-mm (61%) MPR diastolic images. The most sensitive and accurate systolic reconstructions were 3-mm MinIP images. These findings related to viewing in relatively narrow window width and window level settings. Viewing parameters for optimal accuracy in detection of perfusion defects on CTP differ for systolic and diastolic images.

• Incremental value of myocardial perfusion over regional left ventricular function and coronary stenosis by cardiac CT for the detection of acute coronary syndromes in high-risk patients: a subgroup analysis of the ROMICAT trial.

  Authors: Hiram G Bezerra, Ricardo Loureiro, Thomas Irlbeck, Fabian Bamberg, Christopher L Schlett, Ian Rogers, Ron Blankstein, Quynh A Truong, Thomas J Brady, Ricardo C Cury, Udo Hoffmann

  Journal of cardiovascular computed tomography. 11/2011; 5(6):382-91.

  To determine the incremental benefit of assessing myocardial perfusion defects (MPD) for acute coronary syndromes (ACS) over coronary and functional assessment by rest cardiac computed tomographyTo determine the incremental benefit of assessing myocardial perfusion defects (MPD) for acute coronary syndromes (ACS) over coronary and functional assessment by rest cardiac computed tomography (CT) in patients with acute chest pain. Assessment of myocardial perfusion is feasible with cardiac CT; however, the diagnostic value of this assessment in patients at risk for ACS has not been demonstrated. The study included patients who presented to the emergency department with acute chest pain, nonischemic initial electrocardiogram (ECG), and negative cardiac biomarkers but had clinical suspicion for ACS and underwent invasive coronary angiography (ICA). Results were blinded to caregivers and patients. CT data sets were independently assessed for the presence of coronary plaque and stenosis, regional left ventricular function, and myocardial perfusion deficits by 2 blinded observers. Coronary angiography was assessed for the presence of stenosis, TIMI myocardial perfusion grade, and corrected TIMI frame count. The endpoint was ACS during index hospitalization. We analyzed data from 35 subjects (69% male, mean age 58 ± 9 years) of whom 22 (63%) had ACS. The sensitivity and specificity of MPD for ACS were 86% (95% CI: 64%-96%) and 62% (95% CI: 32%-85%), respectively. Combined, MPD and RWMA assessment resulted in specificity and sensitivity of 86% (95% CI: 64%-96%) and 85% (95% CI: 54%-97%), respectively. Adding MPD and RWMA to the assessment for significant stenosis (>50%) resulted in a higher sensitivity of 91% (69-98%) and specificity of 85% (54-97%) and a significantly increased overall diagnostic accuracy when compared with assessment for stenosis (AUC: 0.88 vs 0.79; respectively, P = 0.02). Diagnostic accuracy of CT was not associated with impaired CTFC >40 or myocardial TIMI perfusion grade < 3. Assessment of myocardial perfusion and regional wall motion abnormalities may enhance the ability of CT to detect ACS in patients with acute chest pain.

• Imaging of the aortic valve using fluorodeoxyglucose positron emission tomography increased valvular fluorodeoxyglucose uptake in aortic stenosis.

  Authors: Gergana Marincheva-Savcheva, Sharath Subramanian, Sadia Qadir, Amparo Figueroa, Quynh Truong, Jayanthi Vijayakumar, Thomas J Brady, Udo Hoffmann, Ahmed Tawakol

  Journal of the American College of Cardiology. 06/2011; 57(25):2507-15.

  Because fluorodeoxyglucose positron emission tomography (FDG-PET) imaging provides a noninvasive index of inflammation, we sought to assess whether FDG uptake in the aortic valve (AV) is increased inBecause fluorodeoxyglucose positron emission tomography (FDG-PET) imaging provides a noninvasive index of inflammation, we sought to assess whether FDG uptake in the aortic valve (AV) is increased in aortic stenosis (AS). AS is associated with valvular inflammation. FDG-PET/computed tomography data were retrospectively evaluated in 84 patients (age 73 ± 9 years, 45% female), 42 patients with AS, and 42 age-matched controls. FDG uptake was determined within the AV while blinded to AS severity. Target-to-background ratio (TBR) was calculated as valvular/blood activity. Stenosis severity was established on echocardiography, and presence of AV calcification was independently assessed on computed tomography. The aortic valve PET signal (TBR) was increased in AS compared with controls (median 1.53 [interquartile range (IQR): 1.42 to 1.76] vs. 1.34 [IQR: 1.20 to 1.55]; p < 0.001). Further, compared with controls, TBR was increased in mild (median 1.50 [IQR: 1.36 to 1.75]; p = 0.01) and moderate (median 1.70 [IQR: 1.52 to 1.94]; p < 0.001), but not in severe AS (median 1.49 [IQR: 1.40 to 1.54]; p = 0.08). When subjects were categorized according to AV calcification, valvular FDG uptake was increased in mildly (median 1.50 [IQR: 1.36 to 1.79]; p < 0.01) and moderately (median 1.67 [IQR: 1.50 to 1.85]; p < 0.001), but not severely calcified valves (median 1.51 [IQR: 1.38 to 1.54]; p = 0.15), compared with noncalcified valves (median 1.35 [IQR: 1.20 to 1.52]). This study supports the hypothesis that AS is an inflammatory condition and suggests that inflammation may be reduced in late-stage disease. This may have important implications in the design of studies assessing the effect of therapeutic agents in modifying progression of AS.

• Prognostic value of CT angiography for major adverse cardiac events in patients with acute chest pain from the emergency department: 2-year outcomes of the ROMICAT trial.

  Authors: Christopher L Schlett, Dahlia Banerji, Emily Siegel, Fabian Bamberg, Sam J Lehman, Maros Ferencik, Thomas J Brady, John T Nagurney, Udo Hoffmann, Quynh A Truong

  JACC. Cardiovascular imaging. 05/2011; 4(5):481-91.

  The aim of this study was to determine the 2-year prognostic value of cardiac computed tomography (CT) for predicting major adverse cardiac events (MACE) in patients presenting to the emergencyThe aim of this study was to determine the 2-year prognostic value of cardiac computed tomography (CT) for predicting major adverse cardiac events (MACE) in patients presenting to the emergency department (ED) with acute chest pain. CT has high potential for early triage of acute chest pain patients. However, there is a paucity of data regarding the prognostic value of CT in this ED cohort. We followed 368 patients from the ROMICAT (Rule Out Myocardial Infarction Using Computer Assisted Tomography) trial (age 53 ± 12 years; 61% male) who presented to the ED with acute chest pain, negative initial troponin, and a nonischemic electrocardiogram for 2 years. Contrast-enhanced 64-slice CT was obtained during index hospitalization, and caregivers and patients remained blinded to the results. CT was assessed for the presence of plaque, stenosis (>50% luminal narrowing), and left ventricular regional wall motion abnormalities (RWMA). The primary endpoint was MACE, defined as composite cardiac death, nonfatal myocardial infarction, or coronary revascularization. Follow-up was completed in 333 patients (90.5%) with a median follow-up period of 23 months. At the end of the follow-up period, 25 patients (6.8%) experienced 35 MACE (no cardiac deaths, 12 myocardial infarctions, and 23 revascularizations). Cumulative probability of 2-year MACE increased across CT strata for coronary artery disease (CAD) (no CAD 0%; nonobstructive CAD 4.6%; obstructive CAD 30.3%; log-rank p < 0.0001) and across combined CT strata for CAD and RWMA (no stenosis or RWMA 0.9%; 1 feature-either RWMA [15.0%] or stenosis [10.1%], both stenosis and RWMA 62.4%; log-rank p < 0.0001). The c statistic for predicting MACE was 0.61 for clinical Thrombolysis In Myocardial Infarction risk score and improved to 0.84 by adding CT CAD data and improved further to 0.91 by adding RWMA (both p < 0.0001). CT coronary and functional features predict MACE and have incremental prognostic value beyond clinical risk score in ED patients with acute chest pain. The absence of CAD on CT provides a 2-year MACE-free warranty period, whereas coronary stenosis with RWMA is associated with the highest risk of MACE.

• Use of 100 kV versus 120 kV in cardiac dual source computed tomography: effect on radiation dose and image quality.

  Authors: Ron Blankstein, Michael A Bolen, Rodrigo Pale, Meagan K Murphy, Amar B Shah, Hiram G Bezerra, Ammar Sarwar, Ian S Rogers, Udo Hoffmann, Suhny Abbara, Ricardo C Cury, Thomas J Brady

  The international journal of cardiovascular imaging. 04/2011; 27(4):579-86.

  To evaluate the effective radiation dose and image quality resulting from use of 100 vs. 120 kV among patients referred for cardiac dual source CT exam (DSCT). Prospective data was collected on 294To evaluate the effective radiation dose and image quality resulting from use of 100 vs. 120 kV among patients referred for cardiac dual source CT exam (DSCT). Prospective data was collected on 294 consecutive patients referred for DSCT. For each scan, a physician specializing in cardiac CT chose all parameters including tube current and voltage, axial versus helical acquisition, and use of tube current modulation. Lower tube voltage was selected for thinner patients or when lower radiation was desired for younger patients, particularly females. For each study, image quality (IQ) was rated on a subjective IQ score and contrast (CNR) and signal-to-noise (SNR) ratios were calculated. Tube voltage of 100 kV was used for 77 (26%) exams while 120 kV was used for 217 (74%) exams. Use of 100 kV was more common in thinner patients (weight 166 lbs vs. 199 lbs, P < .001). The effective radiation dose for the 100 and 120 kV scans was 8.5 and 15.4 mSv respectively. Among scans utilizing 100 and 120 kV, there was no difference in exam indication, use of beta blockers, heart rate, scan length and use of radiation saving techniques such as prospective ECG triggering and tube current modulation. The IQ score was significantly higher for 100 kV scans. While 100 kV scans were found to have higher image noise then those utilizing 120 kV, the contrast-to-noise and signal-to-noise were significantly higher (SNR: 9.4 vs. 8.3, P = .02; CNR: 6.9 vs. 6.0, P = .02). In selected non-obese patients, use of low kV results in a substantial reduction of radiation dose and may result in improved image quality. These results suggest that low kV should be used more frequently in non-obese patients.

• Usefulness of comprehensive cardiothoracic computed tomography in the evaluation of acute undifferentiated chest discomfort in the emergency department (CAPTURE).

  Authors: Ian S Rogers, Dahlia Banerji, Emily L Siegel, Quynh A Truong, Brian B Ghoshhajra, Thomas Irlbeck, Suhny Abbara, Rajiv Gupta, Ricardo J Benenstein, Garry Choy, Laura L Avery, Robert A Novelline, Fabian Bamberg, Thomas J Brady, John T Nagurney, Udo Hoffmann

  The American journal of cardiology. 03/2011; 107(5):643-50.

  Newer cardiac computed tomographic (CT) technology has permitted comprehensive cardiothoracic evaluations for coronary artery disease, pulmonary embolism, and aortic dissection within a single breathNewer cardiac computed tomographic (CT) technology has permitted comprehensive cardiothoracic evaluations for coronary artery disease, pulmonary embolism, and aortic dissection within a single breath hold, independent of the heart rate. We conducted a randomized diagnostic trial to compare the efficiency of a comprehensive cardiothoracic CT examination in the evaluation of patients presenting to the emergency department with undifferentiated acute chest discomfort or dyspnea. We randomized the emergency department patients clinically scheduled to undergo a dedicated CT protocol to assess coronary artery disease, pulmonary embolism, or aortic dissection to either the planned dedicated CT protocol or a comprehensive cardiothoracic CT protocol. All CT examinations were performed using a 64-slice dual source CT scanner. The CT results were immediately communicated to the emergency department providers, who directed further management at their discretion. The subjects were then followed for the remainder of their hospitalization and for 30 days after hospitalization. Overall, 59 patients (mean age 51.2 ± 11.4 years, 72.9% men) were randomized to either dedicated (n = 30) or comprehensive (n = 29) CT scanning. No significant difference was found in the median length of stay (7.6 vs 8.2 hours, p = 0.79), rate of hospital discharge without additional imaging (70% vs 69%, p = 0.99), median interval to exclusion of an acute event (5.2 vs 6.5 hours, p = 0.64), costs of care (p = 0.16), or the number of revisits (p = 0.13) between the dedicated and comprehensive arms, respectively. In addition, radiation exposure (11.3 mSv vs 12.8 mSv, p = 0.16) and the frequency of incidental findings requiring follow-up (24.1% vs 33.3%, p = 0.57) were similar between the 2 arms. Comprehensive cardiothoracic CT scanning was feasible, with a similar diagnostic yield to dedicated protocols. However, it did not reduce the length of stay, rate of subsequent testing, or costs. In conclusion, although this "triple rule out" protocol might be helpful in the evaluation of select patients, these findings suggest that it should not be used routinely with the expectation that it will improve efficiency or reduce resource use.

• Positron emission tomography measurement of periodontal (18)f-fluorodeoxyglucose uptake is associated with histologically determined carotid plaque inflammation.

  Authors: Kenneth M Fifer, Sadia Qadir, Sharath Subramanian, Jayanthi Vijayakumar, Amparo L Figueroa, Quynh A Truong, Udo Hoffmann, Udo Hoffman, Thomas J Brady, Ahmed Tawakol

  Journal of the American College of Cardiology. 02/2011; 57(8):971-6.

  This study aimed to test the hypothesis that metabolic activity within periodontal tissue (a possible surrogate for periodontal inflammation) predicts inflammation in a remote atherosclerotic vessel,This study aimed to test the hypothesis that metabolic activity within periodontal tissue (a possible surrogate for periodontal inflammation) predicts inflammation in a remote atherosclerotic vessel, utilizing (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging. Several lines of evidence establish periodontal disease as an important risk factor for atherosclerosis. FDG-PET imaging is an established method for measuring metabolic activity in human tissues and blood vessels. One hundred twelve patients underwent FDG-PET imaging 92 ± 5 min after FDG administration (13 to 25 mCi). Periodontal FDG uptake was measured by obtaining standardized uptake values from the periodontal tissue of each patient, and the ratio of periodontal to background (blood) activity was determined (TBR). Standardized uptake value measurements were obtained in the carotid and aorta as well as in a venous structure. Localization of periodontal, carotid, and aortic activity was facilitated by PET coregistration with computed tomography or magnetic resonance imaging. A subset of 16 patients underwent carotid endarterectomy within 1 month of PET imaging, during which atherosclerotic plaques were removed and subsequently stained with anti-CD68 antibodies to quantify macrophage infiltration. Periodontal FDG uptake was compared with carotid plaque macrophage infiltration. Periodontal FDG uptake (TBR) is associated with carotid TBR (R = 0.64, p < 0.0001), as well as aortic TBR (R = 0.38; p = 0.029). Moreover, a strong relationship was observed between periodontal TBR and histologically assessed inflammation within excised carotid artery plaques (R = 0.81, p < 0.001). FDG-PET measurements of metabolic activity within periodontal tissue correlate with macrophage infiltration within carotid plaques. These findings provide direct evidence for an association between periodontal disease and atherosclerotic inflammation.

• Appropriateness and utilization of cardiac CT: implications for development of future criteria.

  Authors: Meagan K Murphy, Thomas J Brady, Khurram Nasir, G Scott Gazelle, Fabian Bamberg, Quynh A Truong, Wilfred S Mamuya, Suhny Abbara, Thomas H Lee, Ron Blankstein

  Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology. 10/2010; 17(5):881-9.

  The cardiac CT (CCT) appropriateness criteria (AC) were jointly published by multiple societies to ensure effective utilization of CCT. We sought to determine how these criteria apply to CCT scansThe cardiac CT (CCT) appropriateness criteria (AC) were jointly published by multiple societies to ensure effective utilization of CCT. We sought to determine how these criteria apply to CCT scans performed at a tertiary-care hospital. Data were collected from medical records and interviews of 267 consecutive patients referred for CCT. Two physicians designated exam indication as appropriate, inappropriate, or uncertain as per AC, or "not known" if not listed in AC. CCT exam indication was appropriate in 47%, inappropriate in 9%, uncertain in 15%, and not known in 29%. The most common appropriate indication was evaluation of CAD in symptomatic patients with equivocal stress test, whereas the most common inappropriate referral was evaluation of asymptomatic patients with low pretest probability of CAD. Most exams (69%) were for evaluation of CAD, with the remaining exams performed to evaluate other elements of cardiac structure or function. Exams for these non-CAD indications were more likely to be appropriate and less likely to have an undetermined (uncertain or not known) level of appropriateness than those for CAD indications. There was no difference in exam appropriateness whether ordered by cardiologists or internists, but providers who completed training >25 years ago ordered fewer appropriate and more inappropriate exams than younger providers. In applying the AC to a large academic medical center, few CCT exams were inappropriate; however, many patients referred for CCT, particularly for evaluation of CAD, had an indication for which the level of appropriateness remained undetermined. Given the rapid adoption of CCT, these results emphasize the need to refine current criteria for appropriate utilization.

• Evaluation of dual-energy CT for differentiating intracerebral hemorrhage from iodinated contrast material staining.

  Authors: Rajiv Gupta, Catherine M Phan, Christianne Leidecker, Thomas J Brady, Joshua A Hirsch, Raul G Nogueira, Albert J Yoo

  Radiology. 10/2010; 257(1):205-11.

  To evaluate the efficacy of dual-energy computed tomography (CT) in the differentiation of intracerebral hemorrhage (ICH) from iodinated contrast material in patients who received contrast materialTo evaluate the efficacy of dual-energy computed tomography (CT) in the differentiation of intracerebral hemorrhage (ICH) from iodinated contrast material in patients who received contrast material via intraarterial or intravenous delivery. This retrospective study was approved by the local institutional review board, which waived the informed consent requirement for the analysis. Sixteen patients with acute stroke and two with head trauma who had undergone intraarterial or intravenous administration of iodinated contrast material were evaluated by using dual-energy CT to differentiate areas of hyperattenuation secondary to contrast material staining from those representing ICH. A dual-energy CT scanner was used for imaging at 80 and 140 kV, and a three-material decomposition algorithm was used to obtain virtual unenhanced images and iodine overlay images. The sensitivity, specificity, and accuracy of dual-energy CT in the prospective differentiation of intraparenchymal contrast material from hemorrhage were obtained. Follow-up images were used as the standard of reference. There were 28 intraparenchymal areas of hyperattenuation classified at dual-energy CT as iodinated contrast material staining (n = 20, 71%), hemorrhage (n = 5, 18%), or both (n = 3, 11%). Two of the three areas of hyperattenuation seen on both virtual unenhanced and iodine overlay images were related to mineralization. The sensitivity, specificity, and accuracy of dual-energy CT in the identification of hemorrhage were 100% (six of six areas), 91% (20 of 22 areas), and 93% (26 of 28 areas), respectively. Dual-energy CT can help differentiate ICH from iodinated contrast material staining with high sensitivity and specificity in patients who have recently received intraarterial or intravenous iodinated contrast material.

• Incremental diagnostic value of regional left ventricular function over coronary assessment by cardiac computed tomography for the detection of acute coronary syndrome in patients with acute chest pain: from the ROMICAT trial.

  Authors: Sujith K Seneviratne, Quynh A Truong, Fabian Bamberg, Ian S Rogers, Michael D Shapiro, Christopher L Schlett, Claudia U Chae, Ricardo Cury, Suhny Abbara, Thomas J Brady, John T Nagurney, Udo Hoffmann

  Circulation. Cardiovascular imaging. 07/2010; 3(4):375-83.

  The incremental value of regional left ventricular function (LVF) over coronary assessment to detect acute coronary syndrome (ACS) is uncertain. We analyzed 356 patients (mean age, 53+/-12 years; 62%The incremental value of regional left ventricular function (LVF) over coronary assessment to detect acute coronary syndrome (ACS) is uncertain. We analyzed 356 patients (mean age, 53+/-12 years; 62% men) with acute chest pain and inconclusive initial emergency department evaluation. Patients underwent 64-slice contrast-enhanced cardiac computed tomography before hospital admission. Caregivers and patients remained blinded to the results. Regional LVF and presence of coronary atherosclerotic plaque and significant stenosis (>50%) were separately assessed by 2 independent readers. Incremental value of regional LVF to predict ACS was determined in the entire cohort and in subgroups of patients with nonobstructive coronary artery disease, inconclusive assessment for stenosis (defined as inability to exclude significant stenosis due to calcium or motion), and significant stenosis. During their index hospitalization, 31 patients were ultimately diagnosed with ACS (8 myocardial infarction, 22 unstable angina), of which 74% (23 patients) had regional LV dysfunction. Adding regional LVF resulted in a 10% increase in sensitivity to detect ACS by cardiac computed tomography (87%; 95% confidence interval, 70% to 96%) and significantly improved the overall accuracy (c-statistic: 0.88 versus 0.94 and 0.79 versus 0.88, for extent of plaque and presence of stenosis, respectively; both P<0.03). The diagnostic accuracy of regional LVF for detection of ACS has 89% sensitivity and 86% specificity in patients with significant stenosis (n=33) and 60% sensitivity and 86% specificity in patients with inconclusive coronary computed tomographic angiography (n=33). Regional LVF assessment at rest improves diagnostic accuracy for ACS in patients with acute chest pain, especially in those with coronary artery disease and thus may be helpful to guide further management in patients at intermediate risk for ACS.

• Performance of electrocardiographic criteria for left ventricular hypertrophy as compared with cardiac computed tomography: from the Rule Out Myocardial Infarction Using Computer Assisted Tomography trial.

  Authors: Quynh A Truong, Leon M Ptaszek, Elizabeth M Charipar, Carolyn Taylor, Joao D Fontes, Matthias Kriegel, Thomas Irlbeck, Michael Toepker, Christopher L Schlett, Fabian Bamberg, Ron Blankstein, Thomas J Brady, John T Nagurney, Udo Hoffmann

  Journal of hypertension. 05/2010; 28(9):1959-67.

  Cardiac computed tomography (CT) is a state-of-the-art technology that provides an accurate noninvasive method to quantify left ventricular mass for analysis of left ventricular hypertrophy (LVH). WeCardiac computed tomography (CT) is a state-of-the-art technology that provides an accurate noninvasive method to quantify left ventricular mass for analysis of left ventricular hypertrophy (LVH). We aimed to examine seven ECG-based LVH criteria against two CT indexation criteria for LVH: a CT-specific body surface area cutoff and the obesity-independent height criteria. In 333 patients (mean age 53 +/- 12 years, 61% men), 64-slice contrast-enhanced CT was performed and 12-lead surface ECG within 24 h. Left ventricular mass was measured at end-diastole. Using both CT indexation criteria, the cohort was subdivided into patients with LVH and without LVH. The seven ECG criteria for LVH were the Cornell voltage index, Cornell voltage duration product, Cornell/strain index, Sokolow-Lyon index, Romhilt-Estes scores at least 4 and at least 5, and Gubner-Ungerleider. The ECG parameters had high specificities (85-97%) and variable low sensitivities (4-43%) when compared to either CT criteria of LVH. The three Cornell-based methods performed the best (test-positive likelihood ratio: 4.5-6.7), followed by the Sokolow-Lyon and Romhilt-Estes scores (test-positive likelihood ratio: 2.3-4.0). With the exception of the Gubner-Ungerleider criterion, the other six ECG criteria were associated with at least one of the CT-based LVH (adjusted odds ratio 2.4-9.5) and had incremental predictive value beyond that of hypertension history. Using cardiac CT as a gold standard for LVH assessment, ECG criteria for LVH have high specificities with the three Cornell-based criteria providing the best test performance for identifying patients with LVH.