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Jane M Kasper

Publications and source records attributed to Jane M Kasper.

9 recordsLinked to original sources
PubMed2005

Potential clinical impact of variability in the measurement of coronary artery calcification with sequential MDCT.

OBJECTIVE: The potential clinical impact of variability in the measurement of coronary artery calcification with sequential MDCT was evaluated using Agatston, volume, and mass scoring algorithms. SUBJECTS AND METHODS: Fifty-six patients were imaged twice using an identical prospectively ECG-triggered sequential scanning protocol. The Agatston, volume, and mass scores were computed by two observers independently. In addition, a patient's total Agatston score was referenced to an age- and sex-stratified database to determine a percentile ranking. Interscan, interobserver, and intraobserver variability and the resultant impact on patients' risk stratifications were assessed. RESULTS: Significant interscan differences were found for all mean coronary calcium scores (Wilcoxson's signed rank test, p <0.0001). Although the median percentage of interscan variability was low for all scoring methods, the interquartile range was wide, indicating significant variability in the data. Median scores (lower quartile-upper quartile) for observers 1 and 2, respectively, were as follows: Agatston, 5% (0-79%) and 6% (0-83%); volume, 12% (0-51%) and 12% (0-57%); and mass, 14% (0-57%) and 14% (0-58%). Interobserver and intraobserver differences between mean calcium scores were not significant, and consequently, lower interobserver and intraobserver variabilities (narrow interquartile ranges of 0-5%) were observed for all scores. Despite significant interscan differences in calcium scores, the percentile ranking assigned to the two scans differed in only 13% of patients. Interobserver differences resulted in a change in the percentile ranking in 7-9% of patients, whereas intraobserver differences caused a change in only 5% of patients. CONCLUSION: The accuracy of sequential MDCT for coronary calcium quantification is sufficient in most cases for stratification of patient risk.

Adult↗
PubMed2004

Extent of myocardial scarring on nonstress delayed-contrast-enhancement cardiac magnetic resonance imaging correlates directly with degrees of resting regional dysfunction in chronic ischemic heart disease.

BACKGROUND: Hyper-enhancement on delayed-enhancement magnetic resonance imaging (DE-MRI) is a marker of irreversible myocardial injury. Both reversible and irreversible ischemically injured regions of myocardium develop reductions in systolic function compared with unaffected regions. This study evaluated whether there is a relationship between myocardial hyper-enhancement from remote scarring on DE-MRI and the degree of myocardial circumferential shortening (%CS) as determined with dynamic MRI tissue tagging (TAG-MRI) in the setting of chronic ischemic heart disease (CIHD). METHODS: Thirty-five patients with CIHD and 8 control patients underwent nonstress, resting DE-MRI and TAG-MRI. A total of 168 CIHD and 96 control segments from the basal- and middle-thirds of the left ventricle (LV) were selected to achieve a balanced test set. With a 16-segment model, segmental myocardial scarring was graded on the basis of the amount of hyper-enhancement on DE-MRI. With TAG-MRI images, segmental %CS was calculated. RESULTS: Patients with CIHD had lower LV ejection fraction compared with the control patients (28% vs 67%). The %CS of normal segments was notably different from %CS of CIHD segments, regardless of the presence or absence of myocardial hyper-enhancement on DE-MRI. Among the CIHD segments, however, %CS correlated inversely with the amount of myocardial hyper-enhancement from scarring (P <.0001, r = -0.38). CONCLUSIONS: On cardiac MRI for CIHD, myocardial hyper-enhancement correlates inversely with %CS, supporting the direct relationship between the amount of remote myocardial scarring determined with nonstress DE-MRI and baseline resting functional impairment.

Adult↗
PubMed2004

Acute dissection of the descending aorta: noncommunicating versus communicating forms.

BACKGROUND: Noncommunicating dissecting intramural hematoma is an aortic dissection variant, characterized by absent flow within the false lumen. Noncommunicating dissecting intramural hematoma is thought to be more stable than communicating dissection when beginning in the descending aorta. This study assessed clinical characteristics, anatomic characteristics, and 1-year outcomes in acute descending noncommunicating dissecting intramural hematoma versus communicating dissection. METHODS: Retrospective database review identified patients who underwent magnetic resonance or computed tomography imaging revealing acute descending noncommunicating dissecting intramural hematoma or communicating dissection. Comparisons of clinical and anatomic characteristics and 1-year outcomes were performed. RESULTS: Twenty-four noncommunicating dissecting intramural hematoma and 36 communicating dissection cases were identified. Patients with noncommunicating dissecting intramural hematoma were older (68.5 +/- 8.8 versus 61.8 +/- 11.6 years; p < 0.05). Although noncommunicating dissecting intramural hematoma often showed abdominal aorta extension (50%), the infrarenal level was spared. Communicating dissection characteristically extended beyond the diaphragm (89%), including into the infrarenal aorta (28%). There was no significant difference in rates of adverse clinical events for noncommunicating dissecting intramural hematoma versus communicating dissection (13% versus 30%; 0.10 > p > 0.05). By follow-up imaging (87% of population), aortic deterioration was more frequent in noncommunicating dissecting intramural hematoma versus communicating dissection cases (60% versus 15%; p < 0.005). CONCLUSIONS: Acute descending noncommunicating dissecting intramural hematoma and communicating dissection represent two variants, with differing clinical and anatomic characteristics, but comparable levels of 1-year morbidity.

Acute Disease↗
PubMed2003

Do segmented reconstruction algorithms for cardiac multi-slice computed tomography improve image quality?

PURPOSE: To evaluate segmented reconstruction algorithms for spiral multi-slice computed tomography (MSCT) that use data from two cardiac cycles to improve temporal resolution (tau) for imaging of the heart. MATERIALS AND METHODS: An initial group of 78 cardiac patients (heart rates [HR] = 63-167 beats per minute [bpm]) were imaged on a 4-slice, 500 ms gantry rotation time scanner (scanner 1). Images were reconstructed with a single-segment algorithm using data from one cardiac cycle with a reconstruction window of fixed length (tau = 250 ms). Images were also reconstructed with two variants of a multi-segment algorithm using data from two cardiac cycles where only one end of the reconstruction window was fixed and the other end was freely moveable to allow adjustment of tau according to HR: (1) "2-segment fixed start" with fixed start of reconstruction, (2) "2-segment fixed end" with fixed end of reconstruction (for both, tau = 125-250 ms). The resulting image sets were ranked from best to worst (1-3, respectively) in a side-by-side, blinded comparison by two independent readers. A second group of 26 patients (HR = 74-90 bpm) were imaged on a 12-slice, 420 ms gantry rotation time scanner (scanner 2). Data were reconstructed with a single-segment algorithm (tau = 210 ms) and a "2-segment fixed start" algorithm (tau = 105-210 ms) and image sets were ranked from best to worst (1-2, respectively). RESULTS: There was no clear evidence that any one technique is superior for imaging on scanner 1. Reader 1 ranked single-segment images the highest for all HRs, but statistically significant differences among the three algorithms were only found for the lowest HRs (< 80 bpm), where reader 1 preferred single-segment over "2-segment fixed end" techniques (p = 0.048). The highest rankings given by reader 2 varied according to HR: single-segment images were superior for lowest HRs, while "2-segment fixed start" images were superior for HRs > 80 bpm; none of these comparisons reached statistical significance. Improved performance of 2-segment reconstruction was found with scanner 2. Both readers ranked "2-segment fixed start" images the highest (p < 0.01). CONCLUSIONS: The added value of 2-segment cardiac reconstruction algorithms for spiral MSCT was not demonstrated for a 4-slice, 500 ms gantry rotation time scanner but shown to be beneficial for a 12-slice, 420 ms gantry rotation time scanner in the crucial HR range of 74-90 bpm.

Adolescent↗
PubMed2003

Quantitative clinical assessment of chronic anterior myocardial infarction with delayed enhancement magnetic resonance imaging and QRS scoring.

BACKGROUND: Both the regional and global myocardial extent of chronic myocardial infarction (MI) are important prognostic factors for length and quality of life and also crucial for the choice of therapy in patients with ischemic heart disease. Our aim was to develop and validate techniques for comparison between regional and global size of remote anterior MI in the left ventricle quantified with both magnetic resonance imaging (MRI) and electrocardiogram (ECG). METHODS: Delayed-enhancement (DE) MRI was used as a clinical "gold standard" for MI size to evaluate the extent of MI estimated with the commonly available standard 12-lead ECG. A method for comparing global and regional quantifications of MI with DE-MRI and ECG was developed. The Selvester QRS-scoring system was used for estimating MI size electrocardiographically. RESULTS: Twenty-five patients with chronic single anterior MI, documented with DE-MRI, were studied. The best agreement for mean % MI per regional segment of the left ventricle was found in the middle third (26% vs 27%), whereas the most significant discrepancy was found in the apex (56% vs 30%). The global MI size of the left ventricle averaged 21 +/- 9% with DE-MRI and 22% +/- 12% with ECG, with a correlation of r = 0.40 (P <.05). CONCLUSIONS: The current Selvester QRS scoring system performs well for quantifying anterior MI in the mid-regions of the left ventricle. The diagnostic performance of the Selvester QRS-scoring system for quantifying MI in the other regions, particularly the left ventricular apex, can potentially be improved, with DE-MRI as the gold standard.

Adult↗
PubMed2003

Nonstress delayed-enhancement magnetic resonance imaging of the myocardium predicts improvement of function after revascularization for chronic ischemic heart disease with left ventricular dysfunction.

BACKGROUND: The extent of myocardial scarring of the left ventricle (LV) is important in patients with chronic ischemic heart disease (CIHD). With delayed-enhancement magnetic resonance imaging (DE-MRI), scarred myocardium (hyper-enhanced) is easily distinguishable from viable (dark) myocardium. This investigation assessed the use of DE-MRI for predicting functional improvement after coronary artery bypass grafting (CABG) in patients with CIHD and significant LV dysfunction. METHODS: The patient population (n = 29) with CIHD and LV dysfunction (ejection fraction 28% +/- 10%) underwent both DE-MRI, to delineate scarred regions before revascularization, and echocardiography (Echo), to assess segmental function before and after CABG (interval 188 +/- 57 days). Using a 16-segment model, LV myocardium was semiquantitatively analyzed for scarring based on DE-MRI and for improvements in resting function by pre- and post-CABG Echo. RESULTS: Before CABG, 82% of targeted myocardial segments had abnormal contraction; 78% showed scarring, including 38% with greater than mild amounts (25%-100%). Normal contraction was found in 18% of segments before revascularization; scarred areas were identified in 42%, 84% of which had, at most, minimal amounts (0%-24%). Of segments with pre-CABG dysfunction, 82% with no evidence of scar recovered, compared to only 18% with > or =50% scarring. Amount of hyper-enhancement was a very good indicator of improvement of function, especially at the > or =50%/segment threshold; overall accuracy was 0.74 (95% CI 0.66-0.82, P <.001). CONCLUSIONS: In patients with CIHD and significant LV dysfunction, DE-MRI can predict likelihood of functional improvement after revascularization.

Adult↗
PubMed2003

Persistent abnormal left ventricular systolic torsion in dilated cardiomyopathy after partial left ventriculectomy.

OBJECTIVE: Rotation of the left ventricular apex relative to the base, or left ventricular torsion, is related to myocardial contractility and structure and is a sensitive indicator of cardiac dysfunction. We have quantified left ventricular systolic rotation and torsion in patients with dilated cardiomyopathy before and after partial left ventriculectomy in an attempt to characterize the effects of this surgical procedure on ventricular ejection mechanics. METHODS: Magnetic resonance imaging with tissue tagging was performed before partial left ventriculectomy in 24 patients, 9 of whom underwent repeat imaging 3 months after surgery. Left ventricular rotation was quantified in each patient at three short-axis levels: apex, midventricle, and base. Torsion was defined as the difference between basal and apical rotation at any time. Results were subdivided for regional analysis at each level and related to cardiac function (ejection fraction, cardiac index, and velocity of circumferential fiber shortening). RESULTS: Before surgery, left ventricular rotation was regionally heterogeneous and abnormal in magnitude and pattern, and increased end-systolic torsion was associated with better cardiac function. After surgery, clinical indices of cardiac function showed improvement; however, rotation magnitude was unchanged at the apex and reduced at the base and midventricle, particularly in the anterior wall and septum. CONCLUSIONS: The pattern and magnitude of ventricular rotation were impaired by dilated cardiomyopathy. Left ventricular rotation and torsion were further diminished after partial left ventriculectomy, indicating that improvement in clinical indices of cardiac function was not reflective of an improvement in this measure of myocardial mechanics.

Adolescent↗
PubMed2003

Non-invasive assessment of plaque morphology and remodeling in mildly stenotic coronary segments: comparison of 16-slice computed tomography and intravascular ultrasound.

BACKGROUND: Non-invasive identification and characterization of mildly stenotic atherosclerotic lesions is an increasingly important focus of coronary imaging. DESIGN: We examined the accuracy of multi (16)-slice computed tomography (MSCT) for imaging of these lesions in comparison with intravascular ultrasound (IVUS). MATERIALS: Mildly stenotic segments of the left coronary artery were identified by coronary angiography and analyzed using IVUS and contrast-enhanced MSCT. Independent reviewers evaluated the accuracy of MSCT for presence, composition and distribution of atherosclerotic plaque and remodeling response in comparison to IVUS using receiver operating characteristic (ROC) data analysis. RESULTS: Of 46 segments in 14 patients, diagnostic characterization by MSCT was possible in 37 (80.4%) segments. In these segments the accuracy of MSCT for identifying plaque presence, calcification, distribution and positive remodeling was consistently greater than 0.90 (reader 1) and 0.87 (reader 2). CONCLUSION: State-of-the-art MSCT can accurately identify mildly stenotic coronary atherosclerosis and provide an assessment of morphology and remodeling response.

Adult↗