Establishment of Myocardial Strain Measurement Data in Pediatric Patients Without Structural Heart Disease: A Single Center Study.

Accurate assessment of LV systolic function remains a challenge, especially in the pediatric population. Myocardial strain measurement by 2D speckle tracking echocardiography (2DSTE) is a relatively new modality for assessment of regional and global myocardial wall motion. This study aims to establish the normative value among various pediatric age groups at a large pediatric tertiary care institution and to describe the challenges encountered in establishing such strain data. Transthoracic echocardiograms were acquired in 121 healthy children (age 0-21 years) and were retrospectively analyzed. The global longitudinal strain (GLS) was obtained by 2D speckle tracking using Philips Epiq7® and QLAB post processing software. The normative value for left ventricular GLS (%) obtained in our study was - 20.8 ± 2.3 (< 1 year); - 21.4 ± 2.2 (1-4 years); - 19.6 ± 2.4 (5-9 years); - 19.4 ± 2.6 (10-14 years); - 18.9 ± 3.0 (15-21 years). There was a statistically significant difference in GLS between the different age groups. The BMI (kg/m2) of assessed subjects were 14.6 ± 2.3 (< 1 year); 16.3 ± 1.5 (1-4 years); 16.7 ± 2.3 (5-9 years); 21.3 ± 4.6 (10-14 years); 23.9 ± 5.9 (15-21 years). There was no significant difference in GLS by gender or by BMI found in our study. We present our experience with establishment of normative values of 2DSTE in our pediatric echocardiography lab. This study shows that age is the major determinant of variation in peak GLS in healthy subjects, emphasizing the importance of establishment of normative data among various age groups in pediatrics.

Emerging trends in the prenatal diagnosis of complex CHD and its influence on infant mortality in this cohort.

BACKGROUND: Fetal echocardiography is the main modality of prenatal diagnosis of CHD. This study was done to describe the trends and benefits associated with prenatal diagnosis of complex CHD at a tertiary care centre. METHODS: Retrospective chart review of patients with complex CHD over an 18-year period was performed. Rates of prenatal detection along with early and late infant mortality outcomes were studied. RESULTS: Of 381 complex CHD patients born during the study period, 68.8% were diagnosed prenatally. Prenatal detection rate increased during the study period from low-50s in the first quarter to mid-80s in the last quarter (p=0.001). Rate of detection of conotruncal anomalies increased over the study period. No infant mortality benefit was noted with prenatal detection. CONCLUSIONS: Improved obstetrical screening indications and techniques have contributed to higher proportions of prenatal diagnosis of complex CHD. However, prenatal diagnosis did not confer survival benefits in infancy in our study.

Cardiac Physiology for Radiologists: Review of Relevant Physiology for Interpretation of Cardiac MR Imaging and CT.

Cardiac computed tomography (CT) and magnetic resonance (MR) imaging provide clinicians with important insights into cardiac physiology and pathology. However, not all radiologists understand the language and concepts of cardiac physiology that are used daily by cardiologists. This review article covers basic cardiac physiology as it relates to cardiac CT and MR imaging. Topics include a review of the cardiac cycle and left ventricular pressure-volume loops as they relate to different pathologic states, evaluation of cardiac function, and calculation of key parameters such as left ventricular volumes and the ejection fraction. The hemodynamics of cardiac shunts are covered, with an emphasis on factors important to cardiologists, including the ratio of pulmonary flow to systemic flow. Additionally, valvular physiologic function is reexamined, with a focus on understanding pressure gradients within the heart and also the changes associated with valvular pathologic conditions, including measurement of regurgitant fractions in patients with valvular insufficiency. Understanding these basic concepts will help radiologists tailor the reporting of cardiac studies to clinically relevant information.

Describing congenital heart disease by using three-part segmental notation.

The segmental classification of congenital heart disease, first conceptualized nearly 50 years ago, is now well established. The Van Praagh classification system, in particular, is commonly used throughout North America to facilitate communication between physicians from various specialties who are involved in diagnosing and managing congenital cardiovascular abnormalities. In the Van Praagh system, a three-part notation consisting of letters separated by commas and encompassed by a set of braces is used to succinctly describe the visceroatrial situs, the orientation of the ventricular loop, and the position and relation of the great vessels. For example, the notation "{S, D, S}" describes the normal anatomic configuration, in which the morphologic right atrium and largest hepatic lobe are on the patient's right side and the morphologic left atrium, stomach, and spleen are on the left side (situs solitus); the ventricular loop is curved rightward (dextro- or d-loop); and the aorta is posterior to and rightward of the main pulmonary artery (situs solitus). Because the Van Praagh notation imposes on its users a systematic approach to anatomic description, it is a helpful device for structuring the interpretation of imaging studies as well as the reporting of results: First, the morphologic right and left atria and ventricles must be identified; next, the visceroatrial situs and ventricular loop orientation may be determined from the positions of the cardiac chambers; and last, the position and relation of the great vessels (normal, inverted, transposed, or malpositioned) can be established. The article provides concise, step-by-step guidance for applying the Van Praagh system in the radiology reading room.

Rapid Involution of Large Cardiac Rhabdomyomas With Everolimus Therapy.

Rhabdomyoma of the fetal heart is a rare disease accounting for about 1% of all fetal cardiac structural anomalies. They are often found in association with tuberous sclerosis complex. Large cardiac rhabdomyomas can compromise the cardiac function. We report a case of multiple large rhabdomyomas of the right and left ventricles, affecting the cardiac function, which was successfully treated with the chemotherapeutic and immunosuppressive medication everolimus, in a neonate with genetically confirmed tuberous sclerosis complex with multisystem manifestations. There was rapid involution of the tumors in response to everolimus therapy in this infant.

Transthoracic echocardiographic guidance of transcatheter atrial septal defect closure.

This study examines the safety and efficacy of transthoracic echocardiographic (TTE) guidance of atrial septal defect (ASD) device closure. We evaluated 74 patients for TTE-guided ASD closure. Fifty-six patients had successful device implantation using TTE guidance. Twelve patients were referred for surgical ASD closure on the basis of TTE evaluation. Five patients with multiple ASDs or poor transthoracic acoustic windows had ASD device closure guided by transesophageal echocardiography (TEE).

Transmyocardial migration of a temporary epicardial pacing wire: a pediatric case report.

Transmyocardial migration of a retained temporary epicardial pacing wire has been rarely reported in adult patients after heart surgery. We present the case of a child in whom a temporary epicardial pacing wire was discovered incidentally in the right ventricular outflow tract one year after surgical repair of congenital heart disease. The pacing wire was subsequently extracted using the snare method during cardiac catheterization. Clinicians caring for patients after congenital heart surgery should be aware of this uncommon though potentially life-threatening complication.

Ventricular structure and function in children with sickle cell disease using conventional and tissue Doppler echocardiography.

Conventional 2-dimensional, M-mode, and spectral Doppler echocardiographic techniques have documented abnormal ventricular function in adults with sickle cell disease (SCD), but assessments in children are conflicting. Tissue Doppler echocardiography (TDE) provides additional information about myocardial function. Two-dimensional, M-mode, tricuspid regurgitation jet velocity (TRJV) data, and tissue Doppler echocardiographically derived myocardial velocity measurements of left ventricular (LV) and right ventricular function were taken from children with SCD compared to those of similar healthy historical controls and correlated with clinical characteristics and hemoglobin levels. Compared to 55 controls, 54 children with SCD (mean age 14.2 years, range 6 to 21) had a larger left ventricle, greater LV mass, and higher LV fractional shortening; 30% had increased pulmonary artery pressure (TRJV ≥2.5 m/s). Conventional echocardiographic measurements of LV systolic function and spectral Doppler measurements of LV and right ventricular diastolic function were essentially normal, but TDE indicated that 31% of SCD children had evidence of LV diastolic dysfunction (peak early diastolic velocity of LV inflow Doppler/peak early diastolic velocity at lateral mitral valve annulus >8), a finding that correlated with lower hemoglobin levels. Although decreasing hemoglobin levels in children with SCD correlated with LV hypertrophy, LV dilation, and LV diastolic dysfunction, long-term transfusion or hydroxyurea therapy did not affect these measurements. In conclusion, 1/3 of children with SCD had tissue Doppler echocardiographic evidence of LV diastolic dysfunction, which was correlated with hemoglobin levels. Adding serial assessments of ventricular function with TDE to conventional echocardiography may detect early cardiac changes, especially in children with severe anemia.

Enhancing our view of the doubly committed ventricular septal defect.

A case of a doubly committed ventricular septal defect is presented that highlights the value of 3-dimensional echocardiography in the preoperative planning of surgical closure.

Supravalvar mitral ring with complete atrioventricular septal defect: a case report and three-dimensional echocardiography evaluation.

Supravalvar mitral ring (SVMR) is a rare cause of congenital mitral stenosis. It can occur in isolation but often coexists with other cardiac anomalies, such as a ventricular septal defect or left-sided obstructive lesions. Conversely, a complete atrioventricular septal defect (AVSD) is a much more common anomaly. An AVSD may be associated with other major cardiac defects, such as tetralogy of Fallot, transposition of the great arteries, or double-outlet right ventricle. The authors describe what they believe is the first case of SVMR and complete AVSD occurring together; the SVMR was diagnosed by two-dimensional echocardiography, and its morphology could be more accurately delineate using three-dimensional echocardiography.