Cecilia Meagher

Effects of Childhood Primary Hypertension on Carotid Intima Media Thickness: A Matched Controlled Study

To determine whether carotid intima media thickness is increased in children with primary hypertension, the current study compared carotid intima media thickness in hypertensive children with that of normotensive control subjects matched closely for body mass index and determined the relationship between carotid intima media thickness and hypertension severity determined by ambulatory blood pressure monitoring. Children with newly diagnosed office hypertension (n=28) had carotid intima media thickness, left ventricular mass index, and ambulatory blood pressure monitoring performed. Carotid intima media thickness was performed in normotensive control subjects (n=28) matched pairwise to hypertensive subjects for age (±1 year), gender, and body mass index (±10%). Eighty-two percent of subjects were overweight or obese (body mass index ≥85th percentile). The median carotid intima media thickness of hypertensive subjects was greater than that of matched controls (0.67 versus 0.63 mm; P=0.045). In the hypertensive subjects, carotid intima media thickness correlated strongly with several ambulatory blood pressure monitoring parameters, with the strongest correlation for daytime systolic blood pressure index (r=0.57; P=0.003). In the hypertensive group, the prevalence of left ventricular hypertrophy was 32%, but unlike carotid intima media thickness, left ventricular mass index did not correlate with ambulatory blood pressure monitoring. Together, the findings that hypertensive subjects had increased carotid intima media thickness compared with matched controls and that higher carotid intima media thickness correlated with more severe hypertension by ambulatory blood pressure monitoring provide strong evidence that carotid intima media thickness is increased in childhood primary hypertension, independent of the effects of obesity.

Left ventricular mass index in children with white coat hypertension

OBJECTIVES To determine whether children with white coat hypertension (WCH) have evidence of target-organ damage by comparing the left ventricular mass index (LVMI) of subjects with WCH with that of matched normotensive and hypertensive controls. STUDY DESIGN Each subject in the WCH group was matched by body mass index (BMI; +/- 10%), age (+/- 1 year), and sex to a normotensive control and a hypertensive control. Echocardiograms were reviewed to determine the LVMI for each subject. These triple matches were analyzed using repeated-measures analysis of variance to detect differences in LVMI among the 3 groups. RESULTS A total of 27 matched triplets were established. The groups were comparable for sex, age, and BMI. Mean LVMI was 29.2 g/m(2.7) for the normotensive group, 32.3 g/m(2.7) for the WCH group, and 35.1 g/m(2.7) for the sustained hypertensive group (normotensive vs WCH, P = .028; WCH vs sustained hypertension, P = .07). Left ventricular hypertrophy was not present in any subject in the normotensive or WCH groups, but was found in 26% of the sustained hypertensive subjects (P < .001). CONCLUSIONS After controlling closely for BMI, the LVMI in the subjects with WCH was between that of the normotensives and sustained hypertensives, suggesting that WCH may be associated with hypertensive end-organ effects.

Decreased Incidence of Supravalvar Pulmonary Stenosis After Arterial Switch Operation

Background— Supravalvar pulmonary stenosis (SVPS) is frequently observed after arterial switch. Traditionally the coronary arteries are removed from the neopulmonic root by excising the entire sinus of Valsalva. As a result, reconstruction of the neopulmonic root requires a pericardial patch encompassing two-thirds of the anastomosis between the neopulmonic root and pulmonary artery. We present a technique where the coronary arteries are removed as limited buttons of sinus tissue, leaving the transected edge of the neopulmonic root intact. We hypothesize that maintaining native arterial tissue in the anastomosis between the neopulmonic root and the pulmonary artery bifurcation reduces postoperative SVPS. Methods and Results— We performed a retrospective review of neonates with D-transposition of the great arteries undergoing arterial switch procedure from 1996 to 2009. Charts were reviewed, and clinical outcomes recorded for each patient. Most recent echocardiograms were evaluated for right ventricular outflow tract obstruction. A total of 120 patients received arterial switch using this technique. There was 99% survival and no injuries to the coronary arteries regardless of anatomy. Total follow-up was 564 patient-years. Mean follow-up at last clinical visit was 66±46 months. Evaluation of the most recent outpatient echocardiogram revealed an average peak instantaneous gradient across the neopulmonic root of 22.5±5 mm Hg. Only 7 (5%) patients required reintervention (balloon dilation, n=5; surgery, n=2). Conclusions— Our technique of removing the coronary arteries as limited buttons, and anastomosis of the pulmonary artery using only native arterial tissue provides excellent midterm results with minimal SVPS.

A Simple Method of Measuring Thoracic Aortic Pulse Wave Velocity in Children: Methods and Normal Values

BACKGROUND The objective of this study was to define a simple method of measuring thoracic aortic pulse-wave velocity (PWV) using only an aortic length regression equation based on the subjects height and two pulsed Doppler recordings of the aorta. METHODS The thoracic aortas of 80 subjects (age range, 0-20 years) were measured retrospectively by direct echocardiographic visualization. A simple linear regression equation for thoracic aortic length on the basis of height was derived. PWV was defined as the thoracic aortic length, derived from the subjects height, divided by pulse transit time. Pulse transit time was defined as the difference in the time of onset of two pulsed Doppler recordings placed at the level of the aortic valve leaflet tips and the diaphragm. Normative data were retrospectively defined in 206 children. RESULTS Thoracic aortic length was linearly related to subject height by the equation thoracic aortic length (cm)=1.7 cm+0.1 (height [cm]) (R2=0.98, P<.0001). Thoracic aortic PWV was independent of age (median, 3.04 m/s). CONCLUSION Thoracic aortic PWV can be simply calculated from a routine echocardiogram, it is constant throughout childhood, and it may improve the assessment of left ventricular load.

Surgical Strategy for Aortic Coarctation Repair Resulting in Physiologic Arm and Leg Blood Pressures

OBJECTIVE The goal of aortic coarctation repair is laminar aortic blood flow resulting in a negative or absent arm:leg blood pressure (BP) gradient. Despite satisfactory relief of coarctation, associated arch hypoplasia can result in residual obstruction and postoperative upper body hypertension. INTERVENTION We devised a surgical strategy to create a tension-free anastomosis with a diameter as large as both the adjacent proximal and distal aorta using a radically extended end-to-end anastomosis via sternotomy and/or thoracotomy. Sternotomy is chosen when there is significant transverse arch hypoplasia defined as a distal transverse arch ≤ diameter of the left carotid artery, presence of a common brachiocephalic trunk, or coexisting intracardiac lesion requiring repair. Thoracotomy is used in all other cases. RESULTS From 2000 to 2008, 95 consecutive patients were repaired using this approach, 35 with sternotomy and 60 with thoracotomy. At a mean follow-up of 50 ± 23 months, mean systolic BP was 94 ± 10 mm Hg, and 84% of patients had no residual arm:leg BP gradient. Mean arm:leg BP gradient was not statistically different between groups (-8.5 ± 15 sternotomy and -7.0 ± 10 mm Hg thoracotomy, P= .7). With Doppler echocardiography, 96% of patients demonstrated normal early diastolic reversal of blood flow in the descending thoracic aorta. CONCLUSIONS For aortic coarctation repair in infancy, a strategy designed to directly address aortic arch hypoplasia results in excellent intermediate-term results with normal BP, physiologic arm:leg BP relationship, and near normal descending aortic blood flow velocities by Doppler.

Young–Simpson syndrome (YSS), a variant of del(1)(p36) syndrome?

The Young–Simpson syndrome (YSS) and 1p36 deletion syndrome are both characterized by facial and heart abnormalities, congenital hypothyroidism, and severe growth and developmental retardation. However, the YSS is characterized by the presence of blepharophimosis and epicanthus inversus, findings not described in monosomy 1p36 patients. We describe a girl with YSS, who presented with the typical facial findings, global retardation, congenital hypothyroidism, and congenital dilated cardiomyopathy. Comparative genomic hybridization chromosomal microarray analysis showed a 1p36.3 deletion, a finding not previously reported in other YSS cases. We propose that YSS is a variant of the 1p36 deletion syndrome.

Neurodevelopmental outcomes after neonatal cardiac surgery: Role of cortical isoelectric activity

OBJECTIVES Neonates with congenital heart disease are at risk for impaired neurodevelopment after cardiac surgery. We hypothesized that intraoperative EEG activity may provide insight into future neurodevelopmental outcomes. METHODS Neonates requiring surgery had continuous intraoperative EEG and hemodynamic monitoring. The level of EEG suppression was classified as either: slow and continuous; moderate burst suppression; severe burst suppression; or isoelectric (no brain activity for >3 minutes). Follow-up neurodevelopmental outcomes were assessed using the Vineland Adaptive Behavior Scale II (Vineland-II). RESULTS Twenty-one neonates requiring cardiac surgery developed a slow and continuous EEG pattern after general anesthesia. Ten neonates (48%) maintained continuous brain electrical activity with moderate burst suppression as the maximum level of EEG suppression. Eleven neonates (52%) developed severe burst suppression that progressed into an isoelectric state during the deep hypothermic period required for circulatory arrest. However, the duration of this state was significantly longer than circulatory arrest times (111.1 ± 50 vs 22.3 ± 17 minutes; P < .001). At a mean follow-up at 5.6 ± 1.0 years, compared with neonates with continuous brain electrical activity, neonates who developed an isoelectric state had lower Vineland-II scores in communication. There was an inverse relationship between composite Vineland-II scores and duration of isoelectric activity (R = -0.75, P = .01). Of neonates who experienced an isoelectric state, durations of >90 minutes were associated with the lowest Vineland-II scores (125.0 ± 2.6 vs 81.1 ± 12.7; P < .01). CONCLUSIONS The duration of cortical isoelectric states seems related to neurodevelopmental outcomes. Strategies using continuous EEG monitoring to minimize isoelectric states may be useful during complex congenital heart surgery.

Transesophageal echocardiography in pediatric congenital heart disease.

The uses of transesophageal echocardiography have expanded dramatically over the last decade. With advances in technology, this imaging modality has become readily available for evaluation of the complex pediatric population with congenital heart disease. This article discusses the many uses of transesophageal echocardiography in this population, in the outpatient setting, in the peri-operative period, and in the cardiac catheterization laboratory.