Faculty Bibliography

BACKGROUND:It is unknown that dysglycemia in obese adolescents has effects on myocardial deformation that are more pronounced when compared to obesity alone. We hypothesized that obesity associated abnormal glucose tolerance (dysglycemia) would have adverse effects on two-dimensional speckle tracking echocardiography derived longitudinal, radial and circumferential strain (LS, RS, CS) compared to age and gender lean controls. We also examined if changes in deformation would be reflected in abnormal ventricular vascular coupling indices (VVI). METHODS:In a prospective cross-sectional design 39 obese adolescents (15.9 ± 1.7 years; 101.5 ± 39 kg; female - 58%) were compared to age and gender matched lean controls (15.7 ± 1.8 yrs, 60 ± 12.8 kg). Based on results from an oral glucose tolerance test (OGTT), obese adolescents were categorized as obese normoglycemic (ONG, n = 25) or obese dysglycemic (ODG, n = 14). Left ventricular (LV) global and average LS, CS, RS and strain rate were measured. LV ejection fraction and mass index were measured and VVI approximated as ratio of arterial elasticity (Ea) and end-systolic elastance (Ees). RESULTS:Adolescents with ODG had significantly (P = 0.005) impaired global LS (- 20.98% ± 2.8%) compared to controls (- 23.01% ± 2.3%). A similar (P = 0.0027) reduction was observed in average LS for adolescents with ODG (18.87% ± 2.5%) compared to controls (20.49% ± 2%). Global CS was also decreased (P = 0.03) in ODG (- 23.95%) compared to ONG (- 25.80). A similar trend was observed in average CS after multivariate regression for BMI and blood pressure. CS correlated with HbA1c in both groups (P = 0.05). VVI had a negative correlation with both LS (r = - 0.4, P = 0.025) and CS rate (r = - 0.36, P = 0.04). CONCLUSIONS:Myocardial strain and strain rate were significantly altered in obese adolescents. Unfavorable subclinical reductions in global and average CS were more pronounced in adolescents with dysglycemia compared to obese adolescents with normoglycemia and controls. These data indicate progressive worsening of subendocardial function across the spectrum of glucose tolerance. Strain rate was predictive of VVI in obese adolescents, suggesting strain rate may be a sensitive marker for cardiac remodeling in abnormal glucose homeostasis states.

Quantification of left ventricular (LV) mass by echocardiography has not been validated against the gold standard of cardiac magnetic resonance imaging (CMR) in the pediatric population. The purpose of this study was to compare LV mass by two-dimensional and conventional M-mode echocardiography versus CMR in children. Consecutive CMR studies were paired with echocardiograms and retrospectively analyzed in children age ≤ 16 years (3 days old to 16 years old). Studies performed > 3 months between modalities and single ventricle anatomy were excluded. Unindexed LV mass was calculated using M-mode, area-length (AL), and truncated ellipsoid (TE) methods via echocardiography, and compared to cine stack CMR images. There were 46 patients included in the study (both MRI and echocardiography). Good correlations were observed for LV mass measured by CMR and all echocardiographic methods: M-mode (R = 0.965), AL (R = 0.975), and TE (R = 0.975). There was a significant overestimation using TE echocardiography, by a mean of 10.5 g (95% confidence interval 5.7-15.2 g, p < 0.05). There was no significant over- or underestimation of LV mass observed by M-mode or AL echocardiographic measurements, with tight limits of agreement when compared to CMR (95% confidence interval - 5.2 to 4.4 g and - 1.5 to 6.7 g, respectively). Interobserver agreement was good for each of the echocardiographic measurements, but inferior with M-mode (ICC, 0.89) compared to two-dimensional methods (ICC, 0.97). Echocardiographic estimates of LV mass have good correlation with CMR in children. Performance comparison showed AL echocardiographic method provides the most accurate measurement of LV mass with the best reproducibility compared to other methods.

Right atrial (RA) size is a prognostic indicator for heart failure and cardiovascular death in adults. Data regarding use of RA area (RAA) by two-dimensional echocardiography as a surrogate for RA size and allometric modeling to define appropriate indexing of the RAA are lacking. Our objective was to validate RAA as a reliable measure of RA size and to define normal reference values by transthoracic echocardiography (TTE) in a large population of healthy children and develop Z-scores using a validated allometric model for indexing RAA independent of age, sex, and body size. Agreement between RAA and volume by 2D, 3D TTE, and MRI was assessed. RAA not volume by 2D TTE is an excellent surrogate for RA size. RAA/BSA¹ has an inverse correlation with BSA with a residual relationship to BSA (r = - 0.54, p < 0.0001). The allometric exponent (AE) derived for the entire cohort (0.85) also fails to eliminate the residual relationship. The entire cohort divided into two groups with a BSA cut-off of 1 m² to provide the best-fit allometric model (r = 0). The AE by least square regression analysis for each group is 0.95 and 0.88 for BSA < 1 m² and > 1 m², respectively, and was validated against an independent sample. The mean indexed RAA ± SD for BSA ≤ 1 m² and > 1 m² is 9.7 ± 1.3 cm² and 8.7 ± 1.3 cm², respectively, and was used to derive Z-scores. RAA by 2D TTE is superior to 2D or 3D echocardiography-derived RA volume as a measure of RA size using CMR as the reference standard. RAA when indexed to BSA¹, decreases as body size increases. The best-fit allometric modeling is used to create Z scores. RAA/BSA^0.95 for BSA < 1 m² and RAA/BSA^0.88 for those with BSA > 1 m² can be used to derive Z scores.

Background: Hypoplastic left heart syndrome (HLHS) is of the highest risk lesions in congenital heart disease. The initial surgery typically involves the Norwood procedure, frequently with Sano modification. Despite surgical advances, interstage mortality remains approximately 10%, with diminished right ventricular (RV) systolic function a risk factor for death. Tricuspid regurgitation (TR) derived dP/dT has been shown to correlate with catheter derived dP/dT in patients with HLHS, and is frequently used in assessment of RV systolic function. However, in patients without an adequate TR Doppler signal, this modality cannot be used. The purpose of this study was to evaluate the correlation between a Sano derived RV dP/dT and TR derived RV dP/dT in the assessment of RV systolic function following Norwood operation with Sano modification. Methods: An echocardiographic retrospective review was performed in patients following a Norwood/Sano operation, and assessed for the presence of a continuous wave Doppler tracing across the tricuspid valve and Sano shunt. 46 studies met this criteria. A dP/dT for both methods was measured between 1 and 3 m/s, and a qualitative assessment of function was also assigned to each study. Results: The mean value of TR derived dP/ dT and Sano derived dP/dT was 979.9 mmHg/s and 1102.89 mmHg/s respectively. A linear relationship exists between a Sano and TR derived RV dP/dT, where the TR derived RV dP/dT = 387+0.73x, (p=0.001). There was also a statistically significant relationship between the Sano derived dP/dT and the qualitative analysis of RV systolic function, particularly in the higher values. Moderately diminished function was found to have a Sano derived dP/dT of 860 to 1093, mildly diminished 732 to 1325, and normal function 866 to 2048. Conclusions: Sano derived RV dP/dT can be effectively used as a surrogate for TR derived RV dP/dT, which may be of use in patients with inadequate TR. There is a statistically significant correlation between the Sano dP/dT and the qualitative assessment of function (Figure presented)

OBJECTIVES: Residual respiratory motion degrades image quality in conventional cardiac cine MRI (CCMRI). We evaluated whether a free-breathing (FB) radial imaging CCMRI sequence with compressed sensing reconstruction [extradimensional (e.g. cardiac and respiratory phases) golden-angle radial sparse parallel, or XD-GRASP] could provide better image quality than a conventional Cartesian breath-held (BH) sequence in an unselected population of patients undergoing clinical CCMRI. MATERIALS AND METHODS: One hundred one patients who underwent BH and FB imaging in a midventricular short-axis plane at a matching location were included. Visual and quantitative image analysis was performed by two blinded experienced readers, using a five-point qualitative scale to score overall image quality and visual signal-to-noise ratio (SNR) grade, with measures of noise and sharpness. End-diastolic and end-systolic left ventricular areas were also measured and compared for both BH and FB images. RESULTS: Image quality was generally better with the BH cines (overall quality grade for BH vs FB images 4 vs 2.9, p < 0.001; noise 0.06 vs 0.08 p < 0.001; SNR grade 4.1 vs 3, p < 0.001), except for sharpness (p = 0.48). There were no significant differences between BH and FB images regarding end-diastolic or end-systolic areas (p = 0.35 and p = 0.12). Eighteen of the 101 patients had poor BH image quality (grade 1 or 2). In this subgroup, the quality of the FB images was better (p = 0.0032), as was the SNR grade (p = 0.003), but there were no significant differences regarding noise and sharpness (p = 0.45 and p = 0.47). CONCLUSION: Although FB XD-GRASP CCMRI was visually inferior to conventional BH CCMRI in general, it provided improved image quality in the subgroup of patients with respiratory-motion-induced artifacts on BH images.

BACKGROUND: Pulmonary artery intimal spindle cell sarcomas are rare and carry with them a poor prognosis and high rate of recurrence. In extremely rare cases, this tumor can infiltrate the pulmonic valve and manifest as adult-onset pulmonic stenosis. CASE PRESENTATION: We report an unusual case of a patient with symptomatic, adult-onset severe pulmonic stenosis who was referred for possible balloon valvuloplasty but was subsequently found to have pulmonary artery intimal sarcoma infiltrating the pulmonary valve leading to progressive exertional dyspnea. CONCLUSION: The presence of adult-onset pulmonic stenosis should prompt the clinician to investigate further as most cases of pulmonic stenosis are congenital in nature and present early in life. Careful diagnostic evaluation in concert with multimodal imaging should take place to arrive at the correct and challenging diagnosis of sarcoma-induced adult-onset severe pulmonic stenosis. Given the poor prognosis and rapid progression of disease, early diagnosis is crucial.

Background/Hypothesis: The clinical importance of intracardiac echogenic foci(ICEF)on prenatal ultrasound remains debatable amongst pediatric cardiologists and obstetricians. It has previously been discredited as a marker of triploidy and no clear association with congenital heart disease (CHD) has been established. Yet it continues to be a frequent reason for referral for fetal echocardiogram. The aim of this study was to assess the presence of CHD in patients with ICEF and to determine if it represents echocardiographic artifact. We hypothesized that there is no significant association between ICEF and CHD and that ICEF represents echocardiographic artifact. Materials and Methods: The institutional fetal echocardiography database was retrospectively searched for reports containing the diagnosis of echogenic focus from November 2014-November 2016. Each study was evaluated by a single reviewer. The presence of ICEF in the 3 standard views analogous to the apical 4 chamber, parasternal short axis, and parasternal long axis views was recorded. In addition, the presence of CHD, pericardial effusion, and/or fetal arrhythmia for each study was documented. Statistical analysis was performed using cross-tabulation with chi-square analysis. Results: 55 patients, yielding 145 studies were reviewed. 6 patients (10.9%) had CHD, which included VSD(n= 3), PA/VSD(n =2), and vascular ring(n =1). ICEF was noted in all 3 views in 33 studies(23%), in 2 views in 45 studies(31%), in 1 view in 22 studies (15%), and resolved in 45 studies (31%)(see table). Of those studies with ICEF noted in all 3 views, 19%(n=6) were associated with CHD, indicating a significant association in this highly selective population (p =0.039). Conclusions: There is a higher incidence of CHD in fetuses with ICEF compared to the general population. The presence of ICEF was more likely to be identified in multiple views, suggesting it is unlikely echocardiographic artifact

Rapid prototyping may be beneficial in properly selected cases of complex congenital heart disease, providing detailed anatomical understanding that helps to guide potential surgical and cardiac catheterization interventions. We present a case of double-outlet right ventricle, where the decision to obtain a three-dimensional printed model helped for better understanding of the anatomy, with the additional advantage of surgical simulation in planning the surgical approach and type of surgical repair.

BACKGROUND: It is still thought by some that a common wall is to be found in the normal heart between the attachments of the caval and pulmonary veins, with absence of this wall underscoring the presence of sinus venosus defects. Recent findings using episcopic microscopy in developing mice have shown the deficiencies of this notion. Understanding that the superior rim of the oval fossa is a fold, rather than a true septum, which can be distorted in the presence of partially anomalous pulmonary venous drainage, has provided an alternative explanation for the morphogenesis of sinus venosus defects. METHODS: We reviewed our experience with patients suspected of having a sinus venosus defect from August, 2011, through October, 2015, analysing the findings in light of the current hypotheses used to explain the development of the defects, along with correlations made by inspection of autopsy specimens. RESULTS: We evaluated findings from 16 patients, with a mean age of 7.7 years, ranging from 2.7 to 15 years. Of the group, 13 were ultimately diagnosed with a superior sinus venosus defect, two with an inferior defect, and one with isolated anomalous pulmonary venous connection in the absence of an interatrial communication. Initially, two patients were thought to have oval fossa defects, one from each subtype, but were correctly diagnosed following cardiac magnetic resonance interrogation. Anomalous pulmonary venous connections were present in all cases. CONCLUSION: Appreciation of the changes occurring during normal cardiac development helps in understanding the anatomical substrate underscoring the spectrum of sinus venosus defects. The lesions are veno-venous connections due to partially anomalous pulmonary venous connections, producing interatrial communications outside the confines of the interatrial septum.