Evaluating cardiac anatomy as a predictor for success after pulmonary vein isolation for the treatment of atrial fibrillation

Introduction: Atrial Fibrillation is a condition characterized by the production of ectopic beats by the heart. One common treatment for Atrial Fibrillation is catheter guided pulmonary vein isolation (PVI), however this treatment is only effective in around 60-70% of the population. Our research hopes to elucidate a link between cardiac anatomy and successful treatment of A-fib by pulmonary vein isolation. Methods: The medical records for 78 consecutive patients who underwent PVI for atrial fibrillation at Jefferson from July 2013 to March 2016 were gathered. Included in these charts were ECG-gated cardiac CT angiogram and two-year follow up history. Different variables from the imaging data such as left atrial volume, ejection fraction, and pulmonary vein area were analyzed and compared to likelihood of recurrence of A-Fib after PVI. A T-test was used to compare continuous variables in patients who had recurrence versus those that did not and a Chi-Squared Test was used to compare likelihood of recurrence in those with persistent versus paroxysmal A-Fib. Results: Recurrent atrial fibrillation was found in 32/72 (44%) of treated patients by 24 months. Univariate analysis demonstrated a higher incidence of recurrent atrial fibrillation among patients who remained on anti-arrhythmic medications 14/22 = as compared to those who did not 18/50, p = 0.03. There was a lower incidence of recurrent atrial fibrillation in males 20/52 (38%) as compared with females 12/19 (63%), though this difference was only marginally significant (p = 0.056). Multivariate analysis of additional variables with logistic regression demonstrated a marginally significant association of reduced ejection fraction with recurrent atrial fibrillation (p= 0.064). Logistic regression analysis demonstrated no significant differences in recurrence rate based upon age, paroxysmal/persistent fibrillation, left atrial volume, CHADS2 score, pulmonary vein area, and catheter type. Discussion: The only marginal predictors for recurrent atrial fibrillation after PVI were Gender and left ventricular ejection fraction. The other variables including anatomical features and the catheter type used for the procedure had no significant impact on long-term recurrence rates after PVAI. This was a surprising result given other data in the field, which seemed to indicate a link between cardiac anatomy and recurrence of A-Fib after PVI. More research should be conducted in this area, perhaps with a larger data set then was used in this study

Diagnosis of coronary stenosis with CT angiography comparison of automated computer diagnosis with expert readings.

RATIONALE AND OBJECTIVES: To compare computer-generated interpretation of coronary computed tomography angiography (cCTA) by commercially available COR Analyzer software with expert human interpretation. MATERIALS AND METHODS: This retrospective Health Insurance Portability and Accountability Act‑compliant study was approved by the institutional review board. Among 225 consecutive cCTA examinations, 207 were of adequate quality for automated evaluation. COR Analyzer interpretation was compared to human expert interpretation for detection of stenosis defined as ≥50% vessel diameter reduction in the left main, left anterior descending (LAD), circumflex (LCX), right coronary artery (RCA), or a branch vessel (diagonal, ramus, obtuse marginal, or posterior descending artery). RESULTS: Among 207 cases evaluated by COR Analyzer, human expert interpretation identified 48 patients with stenosis. COR Analyzer identified 44/48 patients (sensitivity 92%) with a specificity of 70%, a negative predictive value of 97% and a positive predictive value of 48%. COR Analyzer agreed with the expert interpretation in 75% of patients. With respect to individual segments, COR Analyzer detected 9/10 left main lesions, 33/34 LAD lesions, 14/15 LCX lesions, 27/31 RCA lesions, and 8/11 branch lesions. False-positive interpretations were localized to the left main (n = 16), LAD (n = 26), LCX (n = 21), RCA (n = 21), and branch vessels (n = 23), and were related predominantly to calcified vessels, blurred vessels, misidentification of vessels and myocardial bridges. CONCLUSIONS: Automated computer interpretation of cCTA with COR Analyzer provides high negative predictive value for the diagnosis of coronary disease in major coronary arteries as well as first-order arterial branches. False-positive automated interpretations are related to anatomic and image quality considerations

A glance at imaging bladder cancer.

Purpose: Early and accurate diagnosis of Bladder cancer (BCa) will contribute extensively to the management of the disease. The purpose of this review was to briefly describe the conventional imaging methods and other novel imaging modalities used for early detection of BCa and outline their pros and cons. Methods: Literature search was performed on Pubmed, PMC, and Google scholar for the period of January 2014 to February 2018 and using such words as bladder cancer, bladder tumor, bladder cancer detection, diagnosis and imaging . Results: A total of 81 published papers were retrieved and are included in the review. For patients with hematuria and suspected of BCa, cystoscopy and CT are most commonly recommended. Ultrasonography, MRI, PET/CT using 18F-FDG or 11C-choline and recently PET/MRI using 18F-FDG also play a prominent role in detection of BCa. Conclusion: For initial diagnosis of BCa, cystoscopy is generally performed. However, cystoscopy can not accurately detect carcinoma insitu (CIS) and can not distinguish benign masses from malignant lesions. CT is used in two modes, CT and computed tomographic urography (CTU), both for dignosis and staging of BCa. However, they cannot differentiate T1 and T2 BCa. MRI is performed to diagnose invasive BCa and can differentiate muscle invasive bladder carcinoma (MIBC) from non-muscle invasive bladder carcinoma (NMIBC). However, CT and MRI have low sensitivity for nodal staging. For nodal staging PET/CT is preferred. PET/MRI provides better differentiation of normal and pathologic structures as compared with PET/CT. Nonetheless none of the approaches can address all issues related for the management of BCa. Novel imaging methods that target specific biomarkers, image BCa early and accurately, and stage the disease are warranted

Sixty-four-slice multidetector computed tomography: the future of ED cardiac care

Multidetector computed tomography (MDCT) imaging, a technological advance over traditional CT, is a promising possible alternative to cardiac catheterization for evaluating patients with chest pain in the emergency department (ED). In comparison with traditional CT, MDCT offers increased spatial and temporal resolution that allows reliable visualization of the coronary arteries. In addition, a triple scan, which includes evaluation for pulmonary embolism and thoracic aortic dissection, can be incorporated into a single study. This test will enable emergency physicians to rapidly evaluate patients for life-threatening illnesses and may allow safer and earlier discharges of many patients with chest pain in comparison with a traditional rule-out protocol. In this article, we will highlight the technological advances of MDCT imaging, review the literature on coronary angiography via MDCT, and discuss the future of this technology as it relates to the ED

Characterization and Normal Measurements of the Left Ventricular Outflow Tract by ECG-gated Cardiac CT: Implications for Disorders of the Outflow Tract and Aortic Valve.

RATIONALE AND OBJECTIVES: Studies suggest that electrocardiographically gated coronary computed tomographic angiography provides a clear definition of the left ventricular outflow tract (LVOT), and normal LVOT morphology may not be round, as assumed when the continuity equation is applied during echocardiography. The aims of this study were to demonstrate the morphology of the LVOT on coronary computed tomographic angiography and to establish normal values for LVOT measurements. MATERIALS AND METHODS: Two independent readers retrospectively measured anterior-posterior (AP) and transverse diameters of the LVOT and performed LVOT planimetry on coronary computed tomographic angiographic studies of 106 consecutive patients with normal aortic valves. RESULTS: Excellent interobserver agreement was observed for all measurements (r = 0.78-0.94). The LVOT was ovoid, with a larger transverse diameter than AP diameter during diastole and systole (P \u3c .001). However, the ratio of AP diameter to transverse diameter was closer to 1.0 during systole (P \u3c .001). Mean indexed LVOT area was minimally larger in systole than in diastole (P = .01-.04) and was larger in men than in women during diastole (P ≤ .001) and systole (P ≤ .01). Mean LVOT area indexed to body surface area was 2.3 ± 0.5 cm(2)/m(2) in women and 2.6 ± 0.7 cm(2)/m(2) in men. LVOT area demonstrated significant correlation with aortic root diameter. CONCLUSIONS: The normal LVOT is ovoid in shape. LVOT is more circular during systole, but the AP diameter remains smaller than the transverse diameter throughout the cardiac cycle. The oval shape of the LVOT has important implications when LVOT area is calculated from LVOT diameters. Normal LVOT area values established in this study should facilitate diagnosis of the fixed component of LVOT obstruction

Left atrial volume: comparison of 2D and 3D transthoracic echocardiography with ECG-gated CT angiography.

RATIONALE AND OBJECTIVES: Left atrial volume (LAV) measurement by conventional two-dimensional (2D) transthoracic echocardiography (TTE) may be limited by the geometric model, by suboptimal definition of left atrial endocardium, or by chamber foreshortening. Three-dimensional (3D) TTE is posited to eliminate chamber foreshortening, and LAV measurement by 3D TTE should be more reflective of true LAV. The aim of this study was to compare conventional 2D TTE and newer 3D TTE for measurements of LAV to multidetector computed tomographic (MDCT) measurements using automated chamber reconstruction (ACR). MATERIALS AND METHODS: Twenty-two subjects consented to undergo 2D TTE and 3D TTE immediately prior to or following coronary computed tomographic angiography. LAV was calculated from 2D TTE using the area-length method (ALM) and from 3D TTE with the ALM as well as with a 3D model. Electrocardiographically gated coronary computed tomographic angiography was performed in helical mode. LAV was measured using the ALM as well as ACR. RESULTS: LAV was significantly smaller by 2D TTE (80 ± 21 mL) and 3D-TTE (90 ± 24 mL with the ALM, 61 ± 16 mL with the 3D model) compared to MDCT ACR (120 ± 30 mL) (P \u3c .01). Correlation between MDCT ALM and MDCT ACR was excellent (mean Δ = -1.4 ± 14 mL, r = 0.91). Correlation with MDCT ACR was no better for 3D TTE (r = 0.80) than for 2D TTE (r = 0.80). CONCLUSIONS: LAV is underestimated by both 2D TTE and 3D TTE relative to coronary computed tomographic angiography. Excellent agreement between the ALM and ACR with MDCT imaging suggests that the geometric model plays a negligible role in the underestimation of LAV. Underestimation of LAV by echocardiography is likely related to suboptimal definition of left atrial contour

Adaptive Statistical Iterative Reconstruction-V for Lung Nodule Analysis

Introduction: Low-dose CT in lung cancer screening has demonstrated benefits in select patients. As the traditional filtered back projection (FBP) technique is limited by poor image quality, adaptive statistical iterative reconstruction-V (ASIR-V) algorithm has been developed to achieve higher image quality with processing efficiency. Objective: To investigate the impact of various CT scan parameters on the semi-automated measurement of lung nodules using a Computer Aided Detection (CAD) program. Methods: This IRB-exempt phantom experiment was conducted with a CT scanner capable of ASIR-V algorithm. Eight lung nodules sized 5-12 mm, of solid or ground glass type, were placed inside a multipurpose chest phantom with or without fat slabs. Voltage (kV), current (mA), and ASIR-V levels were varied, and series of CT images were produced. A CAD program semiautomatically analyzed the series and produced nodule diameters and volumes. Nodule measurement variance and the significance of variables were analyzed by one-way ANOVA and univariate regression. Results: Nodule diameter and type contributed to error in both diameter and volume measurements. Current also impacted diameter measurement error. ASIR-V, kV, and fat slabs did not contribute to nodule measurement systematic error. On regression analysis, error is negatively related to mA and solid nodules, but is positively related to nodule diameter or volume. Discussion: These results reinforce that nodule size, type, and mA have the highest influence on CAD software performance nodule quantification accuracy. ASIR-V and kV do not significantly alter the measurement error but, instead, maintain the accuracy of nodule evaluation while minimizing radiation dose

Association between Medicaid expansion status and lung cancer screening exam growth: findings from the ACR lung cancer registry.

PURPOSE: To determine if Medicaid expansion is associated with increased volumes of lung cancer screenings. METHODS: A quasi-experimental study was performed to compare the annual growth rates in lung cancer screenings between states that expanded Medicaid (n = 31) versus those that did not (n = 17). Using the American College of Radiology Lung Cancer Screening Registry, we calculated the average annual growth rate between 2016 and 2019 for both groups. Secondary analyses between these two groups also included calculations of the percentages of studies considered appropriate by USPSTF criteria. RESULTS: No significant difference was identified in the average annual growth in lung cancer screenings between Medicaid expanding and non-expanding states (57.6%, 50.3%, P = 0.51). No difference was observed in the percentage of studies considered appropriate (Medicaid expanding = 89.6%, non-expanding = 90.2%, P = 0.72). At baseline, there were socioeconomic differences between both groups of states. Medicaid expanding states had a more urban population (76.5% versus 67.9%, P = 0.05) and higher average incomes ($56,947,$49,876, P \u3c 0.05). CONCLUSION: No association is found between Medicaid expansion and increasing volumes of lung cancer screening exams. Although no data is available in the registry for screening exams before the implementation of Medicaid expansion (2014), most nationwide estimates of lung screening rates report a low baseline (\u3c5%). Furthermore, despite being advantaged in other ways, such as with a more urban population or with higher incomes, the Medicaid expansion cohort does not demonstrate a higher growth rate. These findings suggest Medicaid expansion alone will not increase lung cancer screenings

Decision analytic model for evaluation of suspected coronary disease with stress testing and coronary CT angiography.

RATIONALE AND OBJECTIVES: The aim of this study was to apply a decision analytic model for the evaluation of coronary artery disease (CAD) to define the optimal utilization of coronary computed tomographic angiography (cCTA) and stress testing. MATERIALS AND METHODS: The model tested in this study assumes that CAD is evaluated with a stress test and/or cCTA and that a patient with positive evaluation results undergoes cardiac catheterization. On the basis of values of sensitivity, specificity, and radiation dose from the published literature and test costs from the Medicare fee schedule, a decision tree model was constructed as a function of disease prevalence. RESULTS: The false-negative rate is lowest when cCTA is used as an isolated test. The false-positive rate is minimized when cCTA is used in combination with stress echocardiography. Effective radiation is minimized by use of stress electrocardiography or stress echocardiography alone or prior to cCTA. When the pretest probability of CAD is low, a strategy that uses stress echocardiography followed by cCTA minimizes the false-positive rate and effective radiation exposure, with relatively low imaging costs and with a false-negative rate only slightly higher than a strategy including stress myocardial scintigraphy. As the pretest probability of CAD increases above 20%, the false-negative rate of stress echocardiography followed by cCTA increases by \u3e5% relative to cCTA alone. CONCLUSION: Effective radiation dose and imaging costs for the workup of CAD may be minimized by an appropriate combination of stress testing and cCTA. A strategy that uses stress echocardiography followed by cCTA is most appropriate for the evaluation of low-risk patients with CAD with a pretest probability \u3c 20%, while cCTA alone may be more appropriate in intermediate-risk patients

Sonoelastography of the Common Flexor Tendon of the Elbow with Histologic Agreement: A Cadaveric Study.

Purpose To determine the correlation of the results of conventional B-mode ultrasonography (US) and compression sonoelastography with histologic results in common flexor tendons of the elbow in human cadavers. Materials and Methods Twenty-five common flexor tendons were evaluated in 16 fresh, unembalmed cadavers of 11 women with a median age of 85 years (range, 71-101 years) and five men with a median age of 78 years (range, 70-88 years). Informed consent was provided according to the last will of the donors. B-mode US results were classified as grade 1, normal tendon with homogeneous fibrillar pattern; grade 2, tendon thickening or hypoechoic areas and/or calcifications in less than 30% of the tendon; or grade 3, hypoechoic areas and/or calcifications greater than 30% of the tendon. Sonoelastographic results were grade 1, blue (hardest) to green (hard); grade 2, yellow (soft); and grade 3, red (softest). The intraclass correlation coefficient was calculated to determine agreement with histologic findings for each B-mode US, sonoelastographic, and combined B-mode US and sonoelastographic examination. Histologic results were grade 1, normal, with parallel fibrillar pattern; grade 2, mild tendinopathy, with cellular infiltration, angiogenesis, or fatty vacuoles; or grade 3, severe tendinopathy, with loss of parallel collagen structure and necrosis. Results Histologic alterations were detected in 44% (11 of 25) of biopsy specimens. Intraclass correlation with histologic results was 0.57 for B-mode US, 0.68 for sonoelastography, and 0.84 for the combination of the two approaches. Conclusion The addition of sonoelastography to B-mode US provided statistically significant improvement in correlation with histologic results compared with the use of B-mode US alone (P \u3c .02). (©) RSNA, 2016 Online supplemental material is available for this article