Aarti Hejmadi Bhat

Fetal Ventricular Mass Determination on Three-Dimensional Echocardiography Studies in Normal Fetuses and Validation Experiments

Background—Estimation of ventricular volume and mass is important for baseline and serial evaluation of fetuses with normal or abnormal hearts. Direct measurement of chamber wall volumes and mass can be made without geometric assumptions by 3D fetal echocardiography. Our goals were to determine the feasibility of using fast nongated 3D echocardiography for fetal volumetric and mass assessments, to validate the accuracy of the ultrasound system and the measurement technique, and if satisfactory, to develop normal values for fetal ventricular mass during the second and third trimesters. Methods and Results—This was a prospective outpatient study of 90 consecutive normal pregnancies during routine obstetric services at Oregon Health & Science University (Portland). Optimized 3D volumes of the fetal thorax and cardiac chambers were rapidly acquired and later analyzed for right and left ventricular mass by radial summation technique from manual epicardial and endocardial traces. Experiments to validate the ultrasound system and measurement technique were performed with modified small balloon models and in vivo and ex vivo small animal experiments. Our study established the feasibility of fetal ventricular mass measurements with 3D ultrasound technology and developed normal values for right and left ventricular mass from 15 weeks’ gestation to term. Conclusions—Nongated fast 3D fetal echocardiography is an acceptable modality for determination of cardiac chamber wall volume and mass with good accuracy and acceptable interobserver variability. The method should be especially valuable as an objective serial measurement in clinical fetal studies with structurally or functionally abnormal hearts.

Validation of volume and mass assessments for human fetal heart imaging by 4-dimensional spatiotemporal image correlation echocardiography in vitro balloon model experiments

Objective. This study was designed to validate a slow‐sweep real‐time 4‐dimensional (4D) spatiotemporal image correlation method for producing quantitatively accurate dynamic fetal heart images using an in vitro pulsatile balloon model and apparatus. Methods. To model fetal heart chambers, asymmetric double‐walled finger stalls (tips of surgical latex gloves) were used and attached to a laboratory‐designed circuit that allowed calibrated changes in the inner balloon volume as well as an intermediate gel mass interposed between the 2 layers. The water‐submerged model was attached to a small‐volume pulsatile pump to produce phasic changes in volume within the inner balloon at a fixed rate. A sonography system with 4D spatiotemporal image correlation (STIC) capabilities was used for 3‐dimensional (3D) and 4D data acquisition. Volume data were analyzed by customized radial summation techniques with 4D data analysis software and compared with known volumes and masses. Results. Fifty‐six individual volumes ranging from 2.5 to 10 mL were analyzed. Volume and mass measurements with 4D STIC were highly correlated (R2 > 0.90). The mean percentage error was better (<6%) for volumes exceeding 4 mL and was as low as 0.3% for 6‐mL estimations. Measurements in the diastolic phase were the most accurate, followed by mass estimations equivalent to chamber walls. There was a wider range of percentage error in the lowest volumes tested (2.5 mL), which might have arisen from difficulties in spatial resolution or distortions from within the model apparatus itself. Resolution limitations of 4D technology in combination with extremely small volume targets may explain higher error rates at these small volumes. Conclusions. Four‐dimensional STIC is an acceptably accurate method for volume and mass estimations in the ranges comparable with mid‐ and late‐gestation fetal hearts. It is particularly accurate for diastolic estimations, for chamber wall mass measurements, and at volumes of greater than 2.5 mL. This study validates use of 4D STIC technology to overcome the limitations of nongated 3D technology for phasic and quantitative assessments in fetal echocardiography.

Congenital heart disease never goes away, even when it has been 'treated': the adult with congenital heart disease

Purpose of review As the specialties of pediatrics and pediatric cardiology continue to forge ahead with better diagnoses, medical care, and surgical results, an expanding population of patients with congenital heart disease (CHD) outgrows the pediatric age group, yet does not quite graduate to routine adult cardiology or general medicine. The adult with congenital heart disease (ACHD) faces medical, surgical, and psychosocial issues that are unique to this population and must be addressed as such. This review attempts to discuss and highlight some of the important advances and controversies brought up in the past year, in the care and management of these patients. Recent findings The past five to 10 years have seen dynamic interest in understanding sequelae of corrected, uncorrected, or palliated congenital heart disease. The search for the ideal surgery, optimal prosthesis, and a smooth transition to adult care continues and is reflected in the vast amount of academic work and publications in this field. Of particular interest, conduit reoperations and single ventricle pathway modifications are still an art and a science in evolution. Summary While all are agreed that there is a pressing need to focus on the delivery of care to the adult with congenital heart disease, this essentially requires a clearer understanding of late sequelae of CHD. The sheer heterogeneity of anatomy, age, surgery, and institutional management protocols can make it difficult to develop clear guidelines. This review attempts to give an up-to-date perspective on some of the new findings related to the more common lesions and problems faced in this group.

Latest advances and topics in fetal echocardiography

Purpose of review Fetal diagnosis and the supporting specialties of perinatology, neonatology, and surgery have made rapid strides in the last decade. Numerous centers are focusing on this multifaceted niche area as the medical field realizes its vast promise and potential. The authors review some of the major advancements in thought and practice in the field of fetal echocardiography while attempting to give a less detailed overview for the less involved perinatologist. Recent findings First trimester fetal echocardiography has been an area of recent interest as transducer technology improves. As a result, optimum timing of first and subsequent scans and the population profile they are to be applied to have become an issue that begs consensus. Three-dimensional and four-dimensional fetal echocardiography have also received a boost for the same reasons, and both are being studied for feasibility and accuracy. Fetal tissue Doppler and spectral Doppler imaging are potential areas for exploration; the early steps have been taken. Awareness of associated ultrasound markers, such as exaggerated nuchal translucency, as clues to the presence of congenital heart disease is important, even if controversial. Summary The issue of missed prenatal diagnosis is disturbing, especially when it arises against a background of tremendous skill and technologic support. Strategies to minimize mistakes in this critical aspect need to be agreed on by the involved teams and put in place in a multidisciplinary manner if they are to have an important impact.

Fetal Cardiovascular Imaging: A Disease-Based Approach

Jack Rychik, Zhiyun Tian, eds. 511 pages. Philadelphia, PA, USA: Elsevier Saunders; 2012.

1112-151 Digital velocity propagation time compared to color M-mode to assess flow propagation across the left ventricular inflow: An in vitro study

152.95. ISBN: 978-1-4160-3172-7 This is the most recent and updated textbook on fetal cardiology in a specialty field that has come into its own over the past decade or so. Fetal cardiology, like many other imaging-intense fields, is a focused combination of knowledge base and imaging expertise. Meticulous attention to imaging detail and compulsive description of segmental anatomy are integral to accurate fetal cardiac diagnosis. This textbook highlights the importance of the knowledge base, and the imaging component, as well. One of its most attractive features is that it uses a case discussion format in pictures to complete a clinical scenario in specific cardiac lesions. Each chapter is very conveniently divided into 3 parts: a didactic component, then a section to describe fetal echocardiographic findings, and then a conclusion with a case discussion tying it all together. Key echocardiographic features set up the framework for each lesion, and each chapter ends with imaging essentials that feed into supporting those key points. As such, this is an innovative format and an effective one that care providers can use for their first and subsequent fetal cardiac diagnosis. …

Myocardial strain rate is a superior method for evaluation of left ventricular subendocardial function compared with tissue Doppler imaging.

heavier (body mass index 32.7±8.9 vs. 31.1±6.3 kg/m2, p 30 kg/m2, 93% vs 90%) and in normal to overweight participants (98% vs 93%)(both p<0.05). Conclusion: introduction of harmonic imaging has increased the yield of LV measurements needed to quantitate LV geometry and function on a population basis, including elderly and obese adults, which have posed a particular challenge to echocardiography.