Faculty Bibliography
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58
Feature Tracking-Derived Peak Systolic Strain Compared to Late Gadolinium Enhancement in Troponin-Positive Myocarditis: A Case-Control Study
Cardiac magnetic resonance (CMR) assesses myocardial involvement in myocarditis (MYO). Current techniques are qualitative, subjective, and prone to interpretation error. Feature tracking (FT) analyzes myocardial strain using CMR and has not been examined in MYO. We hypothesize that regional left ventricular (LV) strain is abnormal in MYO. Regional strain by FT was compared to late gadolinium enhancement (LGE) and troponin leak as measures of myocardial involvement. This single-center, retrospective CMR study reviewed patients with clinical MYO and structurally normal hearts who underwent CMR at our institution. Young adults with normal cardiac anatomy, function, and absent LGE served as controls. MYO patients with documented troponin leak and normal global ejection fraction (EF > 50 %) were included in comparison. FT determined regional myocardial peak systolic strain (pkS) in longitudinal and circumferential distributions. T tests compared strain values between cases and controls. Receiver operating characteristic curves determined pkS values with highest sensitivity and specificity for concurrent troponin leak and LGE. FT was performed on 57 patients: 37 MYO and 20 controls. Twenty-eight cases with normal EF, and 20 control patients were included in final analysis. Nearly all cases with normal function demonstrated abnormal regional pkS (27/28, 96 %). Cases had significantly diminished pkS when compared to controls in all regions except the longitudinal 2C distribution. FT-derived longitudinal and circumferential pkS is sensitive and specific in identifying myocardial involvement, namely the presence of troponin leak and LGE. FT may be a useful adjunctive, objective measure of myocardial involvement in patients with MYO and normal LV function.
PMID: 26717912
ISSN: 1432-1971
CID: 2712232
Assessment of Left Ventricular Mass and Hypertrophy by Cardiovascular Magnetic Resonance Imaging in Pediatric Hypertension
Cardiovascular magnetic resonance (CMR) imaging in adults is considered the gold standard for assessment of left ventricular mass (LVM) and left ventricular hypertrophy (LVH). The authors aimed to evaluate agreement of LVM measurements and LVH determination between echocardiography (ECHO) and CMR imaging in children with hypertension (HTN) confirmed by 24-hour ambulatory blood pressure monitoring (ABPM). The children (n=22) underwent contemporaneous ECHO, CMR imaging, and ABPM. Patients had a mean body mass index of 30.9+/-7.5 (kg/m2 ), and 81.8% had severe HTN. LVM measured by ECHO was 189.6+/-62.1 g and by CMR imaging was 164.6+/-44.7 g (P<.0001). Bland-Altman analysis revealed significant variability between ECHO and CMR imaging in the measurement of LVM. Interobserver error was higher with ECHO than with CMR imaging. ECHO had high sensitivity and low specificity in LVH determination. In conclusion, ECHO overestimates LVM and is less accurate in measuring LVM as compared with CMR imaging in children with HTN. Further prospective study using CMR imaging to assess LVM in children is warranted.
PMID: 26988578
ISSN: 1751-7176
CID: 2712222
Blood Pool Segmentation Results in Superior Virtual Cardiac Models than Myocardial Segmentation for 3D Printing
The method of cardiac magnetic resonance (CMR) three-dimensional (3D) image acquisition and post-processing which should be used to create optimal virtual models for 3D printing has not been studied systematically. Patients (n = 19) who had undergone CMR including both 3D balanced steady-state free precession (bSSFP) imaging and contrast-enhanced magnetic resonance angiography (MRA) were retrospectively identified. Post-processing for the creation of virtual 3D models involved using both myocardial (MS) and blood pool (BP) segmentation, resulting in four groups: Group 1-bSSFP/MS, Group 2-bSSFP/BP, Group 3-MRA/MS and Group 4-MRA/BP. The models created were assessed by two raters for overall quality (1-poor; 2-good; 3-excellent) and ability to identify predefined vessels (1-5: superior vena cava, inferior vena cava, main pulmonary artery, ascending aorta and at least one pulmonary vein). A total of 76 virtual models were created from 19 patient CMR datasets. The mean overall quality scores for Raters 1/2 were 1.63 +/- 0.50/1.26 +/- 0.45 for Group 1, 2.12 +/- 0.50/2.26 +/- 0.73 for Group 2, 1.74 +/- 0.56/1.53 +/- 0.61 for Group 3 and 2.26 +/- 0.65/2.68 +/- 0.48 for Group 4. The numbers of identified vessels for Raters 1/2 were 4.11 +/- 1.32/4.05 +/- 1.31 for Group 1, 4.90 +/- 0.46/4.95 +/- 0.23 for Group 2, 4.32 +/- 1.00/4.47 +/- 0.84 for Group 3 and 4.74 +/- 0.56/4.63 +/- 0.49 for Group 4. Models created using BP segmentation (Groups 2 and 4) received significantly higher ratings than those created using MS for both overall quality and number of vessels visualized (p < 0.05), regardless of the acquisition technique. There were no significant differences between Groups 1 and 3. The ratings for Raters 1 and 2 had good correlation for overall quality (ICC = 0.63) and excellent correlation for the total number of vessels visualized (ICC = 0.77). The intra-rater reliability was good for Rater A (ICC = 0.65). Three models were successfully printed on desktop 3D printers with good quality and accurate representation of the virtual 3D models. We recommend using BP segmentation with either MRA or bSSFP source datasets to create virtual 3D models for 3D printing. Desktop 3D printers can offer good quality printed models with accurate representation of anatomic detail.
PMID: 27041098
ISSN: 1432-1971
CID: 2712202
Use of 3-dimensional printing to demonstrate complex intracardiac relationships in double-outlet right ventricle for surgical planning [Case Report]
PMID: 25904574
ISSN: 1942-0080
CID: 2712262
Use of a 1.0 Tesla open scanner for evaluation of pediatric and congenital heart disease: a retrospective cohort study
BACKGROUND: Open cardiovascular magnetic resonance (CMR) scanners offer the potential for imaging patients with claustrophobia or large body size, but at a lower 1.0 Tesla magnetic field. This study aimed to evaluate the efficacy of open CMR for evaluation of pediatric and congenital heart disease. METHODS: This retrospective, cross-sectional study included all patients
PMCID:4490663
PMID: 26004027
ISSN: 1532-429x
CID: 2712252
Two-dimensional speckle-tracking-derived segmental peak systolic longitudinal strain identifies regional myocardial involvement in patients with myocarditis and normal global left ventricular systolic function
The presence of myocardial late gadolinium enhancement (LGE) by cardiac magnetic resonance (CMR) imaging in concert with electrocardiography and elevated biomarkers helps support the diagnosis of acute myocarditis. Two-dimensional echocardiography is limited to global and qualitative regional function assessment and may not contribute to the diagnosis, especially in the presence of normal LV systolic function. Two-dimensional speckle-tracking (2D-STE)-derived segmental peak systolic (pkS) longitudinal strain (LS) may identify segmental myocardial involvement in myocarditis. We sought to identify an association between segmental pkS, LGE, and troponin levels in patients with myocarditis. Retrospective analysis of myocardial segmental function by 2D-STE segmental strain was compared to the presence of LGE and admission peak troponin levels in patients with acute myocarditis and preserved global LV systolic function. American Heart Association 17-segment model was used for comparison between imaging modalities. Global function was assessed by m-mode-derived shortening fraction (SF). Descriptive statistics and regression analysis were utilized. Forty-four CMRs performed to evaluate for myocarditis were identified. Of the 44, 10 patients, median age 17.5 years (14-18.5 years) and median SF 35 % (28-44 %), had paired CMR and 2D-STE data for analysis, and 161/170 segments could be analyzed by both methods for comparison. PkS LS was decreased in 51 % of segments that were positive for LGE with average pkS of -14.7 %. Segmental pkS LS abnormalities were present in all but one patient who had abnormal pkS circumferential strain. Global pkS LS was decreased in patients with myocarditis. There is a moderate correlation between decreased pkS LS and the presence of LGE by CMR, 2D-STE for myocardial involvement in acute myocarditis can serve as an useful noninvasive adjunct to the existing tests used for the diagnosis of acute myocarditis and might have a role in prognostication.
PMID: 25617227
ISSN: 1432-1971
CID: 2712272
Frequency of aortic dilation in Noonan syndrome
Noonan syndrome (NS) is a genetic disorder caused by mutations altering proteins relevant to RAS/mitogen-activated protein kinase signal transduction. Cardiac involvement is common, most prevalently pulmonary valve stenosis and hypertrophic cardiomyopathy. Because abnormal mitogen-activated protein kinase signaling contributes to the aortopathy in Marfan syndrome and with rare reports of aortic aneurysm in NS, we undertook a retrospective study of ascending aortic anatomy in 37 patients with NS and without confounding medical conditions. Age ranged from 0.6 to 32 years. Based on the most recent echocardiogram, the aortic annulus and root were dilated in the cohort (mean z scores of 1.14 and 0.98, respectively, p <0.005) but the sinotubular junction and ascending aorta were not (mean z scores of 0.05 and 0.19, respectively). The aortic root was aneurysmal (>2 z scores) in 8 subjects (21.6%). PTPN11 mutations were present in 14 subjects, whose aortic status was similar to the cohort overall. Comparison of age and z scores revealed a modest tendency for the aortic annulus and root to dilate over time. Among 13 subjects with multiple imaging studies over an average of 6.8 years, the average z score increased to 0.78 and 0.39 for the aortic annulus and root, respectively. Multivariate analysis revealed that age accounted for 7.0% and 11.0% of the variance in the aortic annular and root diameters, respectively. In conclusion, we found that aortic annular dilation and aortic root aneurysm are prevalent in NS, often presenting during childhood and progressing over time. Further study is needed to identify potential risks associated with these abnormalities.
PMCID:3947366
PMID: 24220280
ISSN: 1879-1913
CID: 2712282
NOVEL APLICATION OF VIRTUAL 3D MODELS DERIVED FROM CARDIAC CT AND MRI TO ASSESS CANDIDACY FOR TWO VENTRICLE REPAIR IN PATIENTS WITH COMPLEX CONOTRUNCAL DEFECTS [Meeting Abstract]
ISI:000359579101256
ISSN: 1558-3597
CID: 2713192
The role of right ventricular function in paediatric idiopathic dilated cardiomyopathy
INTRODUCTION: The prevalence of right ventricular dysfunction in idiopathic dilated cardiomyopathy is incompletely studied in children. Furthermore, right ventricular function may signal worse outcomes. We evaluated recently published right ventricular function echocardiographic indices in identifying dysfunction in children with idiopathic dilated cardiomyopathy and the impact of right ventricular dysfunction on long-term prognosis. METHODS: A retrospective database review of right ventricular function indices in 30 patients with idiopathic dilated cardiomyopathy was compared with 60 age- and sex-matched controls from January, 2001 until December, 2010. Right ventricular function was assessed by Doppler tissue peak systolic S', early and late diastolic E' and A' waves and isovolumic acceleration at the tricuspid valve annulus; pulsed wave Doppler tricuspid valve inflow E and A waves; right ventricular myocardial performance index; tricuspid annular plane systolic excursion; right ventricular fractional area change. RESULTS: Right ventricular systolic and diastolic function in idiopathic dilated cardiomyopathy was significantly impaired. All measured indices except for isovolumic acceleration and fractional area change were significantly reduced, with a p-value less than 0.05. There was no right ventricular index predictive of death or transplantation. Patients with poor outcome were significantly more likely to need inotropic support (p-value equal to 0.018), be placed on a ventricular assist device (p equal to 0.005), and have a worse left ventricular ejection fraction z-score (p-value equal to 0.002). CONCLUSION: Right ventricular dysfunction is under-recognised in children presenting with idiopathic dilated cardiomyopathy. The need for clinical circulatory support and left ventricular ejection fraction z-score less than minus 8 were primary determinants of outcome, independent of the degree of derangement in right ventricular function.
PMID: 22914442
ISSN: 1467-1107
CID: 2712322
Comparison between proximal thoracic vascular measurements obtained by contrast-enhanced magnetic resonance angiography and by transthoracic echocardiography in infants and children with congenital heart disease
Accurate assessment of the proximal thoracic vasculature in infants and children with congenital heart disease (CHD) is vital for deciding the appropriate surgical or interventional procedure and predicting outcomes. This information usually is obtained by transthoracic echocardiography (TTE). Contrast-enhanced magnetic resonance angiography (CE-MRA) frequently is used to obtain diagnostic data when the image quality by TTE is limited. Calculation of z-scores for measurements obtained by CE-MRA in this population currently is not possible due to the lack of normative data. A reasonable agreement between vessel dimensions by CE-MRA and TTE will allow the use of TTE-based z-scores on measurements from CE-MRA. This study examines the accuracy and agreement of proximal thoracic vascular measurements obtained by CE-MRA versus TTE. Infants and children younger than 3 years with CHD who had a CE-MRA between August 2006 and May 2011 were retrospectively identified. Main and branch pulmonary arteries, ascending aorta, distal transverse arch, and aortic isthmus were measured from CE-MRA and TTE in analogous imaging planes and locations by two investigators blinded to each other. The study enrolled 35 subjects with CHD. The median age was 129 days (range, 0-1077 days), and the median weight was 5.8 kg (range, 2.16-17 kg). The median interval between the two imaging methods was 9 days (range, 0-60 days). Data analysis was performed with 129 of the 210 possible paired measurements. The remaining 81 paired measurements could not be performed due to inaccurate visualization of vessel borders or an unavailable imaging plane from TTE, CE-MRA, or both. The range of vessel sizes measured from 2.8 to 23.4 mm. There was excellent correlation between CE-MRA and TTE (r = 0.94, p < 0.001). The mean difference between the measurements was -0.1 +/- 1.2 mm, and the limits of agreement were -2.5 to 2.3 mm. Proximal thoracic vascular measurements obtained by CE-MRA and TTE in infants and children with CHD have a strong correlation. The agreement between these two imaging methods is adequate. Until normative data for vessel size measurements obtained from CE-MRA are available for this population, TTE-based z-scores can be applied to the measurements obtained by CE-MRA.
PMID: 22923009
ISSN: 1432-1971
CID: 2712312
