Periscopic technique in Norwood operation is associated with better preservation of early ventricular function
Objective/UNASSIGNED:Although the right ventricle (RV) to pulmonary artery conduit in stage 1 Norwood operation results in improved interstage survival, the long-term effects of the ventriculotomy used in the traditional technique remain a concern. The periscopic technique (PT) of RV to pulmonary artery conduit placement has been described as an alternative technique to minimize RV injury. A retrospective study was performed to compare the effects of traditional technique and PT on ventricular function following Norwood operation. Methods/UNASSIGNED:A retrospective study of all patients who underwent Norwood operation from 2012 to 2019 was performed. Patients with baseline RV dysfunction and significant tricuspid valve regurgitation were excluded. Prestage 2 echocardiograms were reviewed by a blinded experienced imager for quantification of RV function (sinus and infundibular RV fractional area change) as well as for regional conduit site wall dysfunction (normal or abnormal, including hypokinesia, akinesia, or dyskinesia). Wilcoxon rank-sum tests were used to assess differences in RV infundibular and RV sinus ejection fraction and the Fisher exact test was used to assess differences in regional wall dysfunction. Results/UNASSIGNED:Â =Â .002). Conclusions/UNASSIGNED:The PT for RV to pulmonary artery conduit in Norwood operation results in better preservation of early RV global and regional systolic function. Whether or not this benefit translates to improved clinical outcome still needs to be studied.
Surgical Management of Giant Intrapericardial Teratoma Encasing the Coronary Artery
Intrapericardial teratomas are rare, predominantly benign tumors that warrant surgical resection in the neonatal period because of their potential detrimental effects on the cardiorespiratory system. Surgical resection can be a challenge when the tumor encases and obscures a coronary artery. Adherence to certain operative principles is necessary to achieve successful outcomes.
Inferior Right Ventricular Wall Thickness by Echocardiogram: A Novel Method of Assessing Hypertrophy in Neonates and Infants
An established echocardiographic (echo) standard for assessing the newborn right ventricle (RV) for hypertrophy has not been thoroughly developed. This is partially due to the RV's complex architecture, which makes quantification of RV mass by echo difficult. Here, we retrospectively evaluate the thickness of the inferior RV wall (iRVWT) by echo in neonates and infants with normal cardiopulmonary physiology. Inferior RVWT was defined at the medial portion of the inferior wall of the RV at the mid-ventricular level, collected from a subxiphoid, short axis view. iRVWT was indexed to body surface area (BSA) to the 0.5 power and normalized to iLVWT to explore the best normalization method. Ninety-eight neonates and 32 infants were included in the final analysis. Mean age for neonates and infants was 2Â days and 59Â days, respectively. Meanâ€‰Â±â€‰SD for neonate and infant end-diastole iRVWT was 2.17â€‰Â±â€‰0.35Â mm and 1.79â€‰Â±â€‰0.28Â mm, respectively. There was no residual relationship between the index iRVWT and BSA (râ€‰=â€‰0.03, pâ€‰=â€‰NS). In the infant cohort, the iRVWT was significantly lower and iLVWT was significantly higher compared to neonate, consistent with known physiologic changes of RV and LV mass. Thus, iRVWT may serve as a reliable and accurate proxy for RV mass and the parameter warrants further evaluation.
Diagnosis of anomalous origin of the right subclavian artery from the right pulmonary artery in a patient with D-transposition of the great arteries utilizing transthoracic echocardiography
Diagnosis of anomalous origin of the right subclavian artery (AORSA) from the right pulmonary artery (RPA) is usually made using CT, MRI, or invasive angiography. We report a patient diagnosed using transthoracic echocardiography (TTE). A newborn girl prenatally known to have d-TGA presented with cyanosis sparing the right hemithorax and arm. Oxygen saturations on the right hand were persistently higher than on the right ear and other extremities. Repeat TTE using a modified echocardiographic imaging plane allowed for full visualization of the entire subclavian artery course, revealing AORSA from RPA. We discuss further the approach to echocardiographic diagnosis and surgical implications.
Left Ventricular Mass Quantification by Two-Dimensional Echocardiography in a Pediatric Population: Correlation with Cardiac Magnetic Resonance Imaging
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 ageâ€‰â‰¤â€‰16Â years (3Â days old to 16Â years old). Studies performedâ€‰>â€‰3Â 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 (Râ€‰=â€‰0.965), AL (Râ€‰=â€‰0.975), and TE (Râ€‰=â€‰0.975). There was a significant overestimation using TE echocardiography, by a mean of 10.5Â g (95% confidence interval 5.7-15.2Â g, pâ€‰<â€‰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 -â€‰5.2 to 4.4Â g and -â€‰1.5 to 6.7Â 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.
Validation of Right Atrial Area as a Measure of Right Atrial Size and Normal Values of in Healthy Pediatric Population by Two-Dimensional Echocardiography
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 (râ€‰=â€‰-â€‰0.54, pâ€‰<â€‰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 1Â m2 to provide the best-fit allometric model (râ€‰=â€‰0). The AE by least square regression analysis for each group is 0.95 and 0.88 for BSA <â€‰1Â m2 and >â€‰1Â m2, respectively, and was validated against an independent sample. The mean indexed RAAâ€‰Â±â€‰SD for BSAâ€‰â‰¤â€‰1Â m2 and >â€‰1Â m2 is 9.7â€‰Â±â€‰1.3Â cm2 and 8.7â€‰Â±â€‰1.3Â 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/BSA0.95 for BSAâ€‰<â€‰1Â m2 and RAA/BSA0.88 for those with BSAâ€‰>â€‰1Â m2 can be used to derive Z scores.
Normal Left Ventricular Size in Premature Newborns by the Echocardiographic Bullet Method
Optimal radiologic position of an umbilical venous catheter tip as determined by echocardiography in very low birth weight newborns
OBJECTIVE: To compare chest X-ray with echocardiogram (ECHO) in the localization of an umbilical venous catheter (UVC) tip in very low birth weight infants (VLBW). Secondary objectives determined the association between techniques for tip placement by the vertebral body level on X-ray, as well as the length of the thoracic inferior vena cava-right atrial (TIVC-RA) junction by ECHO. STUDY DESIGN: Prospective, sequentially enrolled, masked, single regional perinatal center study. Shortly after birth, one or more anterior-posterior X-rays were ordered by the clinical team to verify that the UVC tip was fixed in the central right atrium (cRA) or at the TIVC-RA junction. An echocardiogram was performed as soon as possible after the last X-ray and UVC tip location was interpreted by a pediatric cardiologist. The pediatric radiologist and cardiologist were masked with regard to each other's reading. RESULTS: The newborns (n = 51) were 27 (+/-3) weeks by gestational age with birth weights of 1029 (+/-288) grams (mean+/-SD). The radiologist read 50 UVC tips (98%) in the cRA or TIVC-RA junction and 1 (2%) in the LA. The cardiologist read 22 (43%) in the cRA or TIVC-RA, 21 (41%) in the LA and 8 (16%) tips could not be located in the heart. When the UVC tip was interpreted by X-ray as located in the TIVC-RA junction 8/29 (28%) were in the LA by echocardiogram. There was no agreement between vertebral level and tip position in the TIVC-RA junction, RA or LA. The TIVC-RA junction measured 6+/-1 mm and correlated with birth weight r = 0.54 (p < 0.001). CONCLUSION: In VLBW newborns, placement of the UVC tip into the cRA or TIVC-RA junction by X-ray does not avoid misplacement in the left atrium as demonstrated by echocardiography. For VLBW infants, it is suggested that echocardiography may be helpful in verifying that the original placement or migration of the UVC tip into the LA has not occurred.
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.
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.