Pediatric nomograms for left ventricle biplane 2D volumes in healthy Caucasian children

BACKGROUND

Left ventricular (LV) volumes are basic parameters used to estimate ventricular size and function; however, normal values are not available in children. The aim of our study is to provide normal values for LV volumes (measured with the biplane Simpson method) in healthy children.

MATERIALS AND METHODS

We prospectively studied 1320 healthy Caucasian Italian children (age 0 days-17 years, 49.4% female). Echocardiographic measurements on LV volumes were performed. Age, heart rate (HR), and body surface area (BSA) were used as independent variables in different analyses to predict the mean values of each measurement.

RESULTS

Models with exponential (ln[y] = a + b*ln[x]) equations resulted in the best fit for LV volumes. The association with BSA was found to be stronger than the association of HR and age. Thus BSA was used for normalization of our data. Predicted values and Z-score boundaries by BSA are provided.

CONCLUSIONS

We report normal values for 2D biplane LV volumes in a population of healthy children. These data cover a gap in current pediatric echocardiographic nomograms and may serve as baseline for evaluation of children with cardiac defects characterized by LV dilatation or hypoplasia.

Selective perfusion of coronary vasculature in preterm sheep: a methodological innovation undermined by unfavourable operation of the foramen ovale

Antenatal cardiac intervention affords new prospects for hypoplastic left heart syndrome. Its success, however, may come not only from absence of impediments to blood flow but also from a sufficiently developed cardiac wall. Here, we examined the feasibility to perfuse selectively the fetal coronary circulation for treatment with growth promoting agents. Pregnant sheep (94-114 days gestation, term 145 days) were used. An aortic stop-flow procedure was developed for intracoronary access in the nonexposed fetus and human mesenchymal stem cells and their exosomes served as test agents. We found that aortic stop-flow ensures preferential distribution of fluorescent microspheres to the heart. However, intracoronary administration of stem cells or exosomes was detrimental, with fetal demise occurring around surgery or at variable intervals afterwards. Coincidentally, stop-flow caused by itself a marked rise of intraluminal pressure within the occluded aorta along with histological signs of coronary obstruction. We conclude that it is feasible to perfuse selectively the coronary circulation of the preterm fetus, but treatments are not compatible with survival of the animals. The cause for failure is found in the absence of hemodynamic compensation to stop-flow via a left-to-right shunt. This unexpected event is attributed to a largely membranous foramen ovale, characteristic of sheep, that collapses under pressure.

Cardiac Children's Hospital Early Warning Score: Italian Validation

BACKGROUND/PURPOSE

The Cardiac Children's Hospital Early Warning Score (C-CHEWS) is an early warning scale used to identify paediatric patients experiencing clinical deterioration which may warrant a transfer to an ICU. However, no studies have tested the C-CHEWS in an Italian paediatric cardiac population. The aims of this study were to translate/back-translate and validate the Italian version of the C-CHEWS and its algorithm.

DESIGN AND METHOD

Retrospective study. Sensitivity, specificity, accuracy, positive predictive value, negative predictive value were used to evaluate the performance of C-CHEWS. In additions the Cohen's kappa statistic was calculated to evaluate the agreement between patient's status described by C-CHEWS score (≥5) and actual ICU transfer.

RESULTS

High discrimination was observed for sensitivity (81.5%), specificity (99.6%), accuracy (99.7%), positive predictive value (86.7%), and negative predictive value (99.8%). The Cohen's kappa score was observed to be equal to 0.837 (p-value <0.001) indicating there was excellent significant agreement between a C-CHEWS score ≥ 5 and effective evaluation for patients transfer to an ICU.

CONCLUSION

The Italian version of the C-CHEWS proved to be a sensitive, specific and reliable tool in the early detection of a physical deterioration of hospitalized paediatric cardiac surgical patients.

PRACTICE IMPLICATIONS

This tool may help doctors, nurses and all healthcare professionals to promptly recognize and treat clinical deterioration and facilitate urgent transfers to the PICU.

Double Orifice Mitral Valve in Tricuspid Atresia: A Rare Association

We here report a neonate with prenatal echocardiographic diagnosis of tricuspid atresia, with normally related great vessels, and large ventricular septal defect. This diagnosis could be confirmed with echocardiography at birth. An additional double mitral orifice was also seen. This is a very rare association.

Prognostic Value of a New Lung Ultrasound Score to Predict Intensive Care Unit Stay in Pediatric Cardiac Surgery

BACKGROUND

Lung ultrasound (LUS) in pediatric cardiac surgery is gaining consensus. We (1) evaluated the prognostic value of a new LUS-score in pediatric cardiac surgery, and (2) compared LUS-score to conventional risk factors including age, The Society of Thoracic Surgeons/European Association of Cardio-Thoracic Surgery (STAT) score, cardiopulmonary bypass time, and prognostic biomarkers including brain natriuretic peptide and cystatin-C.

METHODS

LUS examinations were performed in 237 children (median age, 0.55 years; interquartile range, 0.09-4.15 years) at 12 to 36 hours after surgery. For each hemithorax, 3 areas (anterior/lateral/posterior) were evaluated in the upper and lower halves, constituting 12 total scanning areas. For each site a score was assigned: 0 (rare B lines), 1 (separated B lines), 2 (coalescent B lines), 3 (loss of aeration), and total LUS score was calculated as sum of all sites. The primary endpoints were intensive care unit length of stay and extubation time.

RESULTS

The mean total LUS score was 12.88 ± 6.41 (range, 0-26) and was higher in newborns (16.77 ± 5.25) compared with older children (5.36 ± 5.57; P < .001). On univariate analysis, LUS score was associated inversely with age (beta 0.26; P = .004) and body surface area (beta 3.41 P = .006) and positively with brain natriuretic peptide (beta 1.65; P < .001) and cystatin-C (beta 2.41; P < .001). The LUS score, when added as continuous predictor to a conventional risk model (age, STAT score, and cardiopulmonary bypass time) emerged significant both for intensive care unit length of stay (beta 0.145, P = .047) and extubation time (beta 1.644; P = .024). When single quadrants were analyzed, only anterior LUS score was significant (intensive care unit length of stay beta, 0.471; P = .020; extubation time beta 5.530; P = .007).

CONCLUSIONS

Our data show the prognostic incremental value of a new LUS score over traditional risk factors in pediatric cardiac surgery.

Normal basic 2D echocardiographic values to screen and follow up the athlete's heart from juniors to adults: What is known and what is missing. A critical review

In the last few years, multiple echocardiographic nomograms have been published. However, normal values calculated in the general population are not applicable to athletes, whose hearts may be enlarged and hypercontractile. Accordingly, athletes require specific nomograms. Our aim is to provide a critical review of echocardiographic nomograms on two-dimensional (2D) measures for athletes. We performed a systematic search in the National Library of Medicine for Medical Subject Headings and free text terms including echocardiography, athletes, normal values and nomograms. The search was refined by adding the keywords heart, sport, elite, master, children and young. Twenty-eight studies were selected for the final analysis. Our research revealed that currently available ranges of normality for athletes reported by different authors are quite consistent, with limited exceptions (e.g. atria, aorta). Numerical and methodological limitations, however, emerged. Numerical limitations included a limited sample size (e.g. < 450 subjects) of the population assessed and the paucity of data in women, non-Caucasian athletes, and junior and master athletes. Some data on M-mode measurements are available, while those for some specific structures (e.g. left atrial (LA) area and volumes, right ventricular diameters and aorta) are limited or rare (e.g. LA area). There was heterogeneity in data normalization (by gender, sport type and ethnicity) and their expression was limited to mean values (Z-scores have rarely been employed), while variability analysis was often lacking or incomplete. We conclude that comprehensive nomograms using an appropriate sample size, evaluating a complete dataset of 2D (and three-dimensional) measures and built using a rigorous statistical approach are warranted.

Normative Data for Left and Right Ventricular Systolic Strain in Healthy Caucasian Italian Children by Two-Dimensional Speckle-Tracking Echocardiography

BACKGROUND

There is an increasing interest in echocardiographic strain (ε) measurements for the assessment of ventricular myocardial function in children; however, pediatric nomograms remain limited. Our aim was to establish pediatric nomograms for the left ventricular (LV) and the right ventricular (RV) ε measured by two-dimensional speckle-tracking echocardiography (2D-STE) in a large cohort of healthy children prospectively enrolled.

METHODS

Echocardiographic measurements included STE LV longitudinal and circumferential and RV longitudinal global end-systolic ε. Age, weight, height, heart rate (HR), and body surface area (BSA) were used as independent variables in different analyses to predict the mean values of each measurement. Echocardiograms were performed by Philips-iE33 systems (Philips, Bothell, WA) and offline measurements on Philips-Q-Lab-9.

RESULTS

In all, 721 subjects (age 31 days to 17 years; 48% female) were studied. Low coefficients of determination (R²) were noted among all of the ε parameters evaluated and adjusted for age, weight, height, BSA, and HR (i.e., R² all ≤ 0.10; range, 0.01-0.088). This hampered the possibility of performing z-scores with a sufficient reliability. Thus, we are limited to presenting data as mean values (±SD) stratified for age groups and divided by gender. LV longitudinal ε values decreased with age (P < .001), while no significant age-related variations were noted for RV longitudinal ε. A significant base-to-apex (lowest to highest) gradient in circumferential LV ε values was noted at all ages (P < .001).

CONCLUSIONS

We report pediatric echocardiographic normative data for 2D-STE for the LV and RV ε by using vendor-specific software. Our results confirm previous observations, showing only little variations of strain parameters with age and gender.

Adult echocardiographic nomograms: overview, critical review and creation of a software for automatic, fast and easy calculation of normal values

There is a crescent interest on normal adult echocardiographic values and the introduction of new deformation imaging and 3D parameters pose the issue of normative data. A multitude of nomograms has been recently published, however data are often fragmentary, difficult to find, and their strengths/limitations have been never evaluated.

AIMS

(I) to provide a review of current echocardiographic nomograms; (II) to generate a tool for easy and fast access to these data. A literature search was conducted accessing the National Library of Medicine using the keywords: 2D/3D echocardiography, strain, left/right ventricle, atrial, mitral/tricuspid valve, aorta, reference values/nomograms/normal values. Adding the following keywords, the results were further refined: range/intervals, myocardial velocity, strain rate and speckle tracking. Forty one published studies were included. Our study reveals that for several of 2D/3D parameters sufficient normative data exist, however, a few limitations still persist. For some basic parameters (i.e., mitral/tricuspid/pulmonary valves, great vessels) and for 3D valves data are scarce. There is a lack of studies evaluating ethnic differences. Data have been generally expressed as mean values normalised for gender and age instead of computing models incorporating different variables (age/gender/body sizes) to calculate z scores. To summarize results a software (Echocardio-Normal Values) who automatically calculate range of normality for a broad range of echocardiographic measurements according to age/gender/weight/height, has been generated. We provide an up-to-date and critical review of strengths/limitation of current adult echocardiographic nomograms. Furthermore we generated a software for automatic, easy and fast access to multiple echocardiographic normative data.

Echocardiographic nomograms for upper abdominal aorta Doppler systolic wave values and systo-diastolic diameters variations in children

BACKGROUND

Abdominal aorta pulsatility and blood flow patterns are important diagnostic indicators in congenital heart disease. Reference values for these indexes are lacking.

METHODS

We prospectively studied abdominal aorta pulsed-wave Doppler systolic peak velocity, deceleration time, and wave duration, and two-dimensional vessel diameters in systole and diastole in healthy Caucasian children. Heteroscedasticity was accounted for by White or Breusch-Pagan test. Age, weight, height, heart rate (HR), and body surface area (BSA) were used as independent variables in different analyses to predict the mean values of each measurement. Structured Z-scores were then computed.

RESULTS

In all, 853 subjects (age 0 days to 17 years; 45% females; BSA 0.12-2.12m²) were studied. The predicted values and Z-score boundaries are presented. Data are also presented as mean±2 SDs for a given BSA.

CONCLUSIONS

We report paediatric echocardiographic nomograms for multiple proximal abdominal aorta parameters including pulsed-wave Doppler systolic velocities, deceleration time, wave duration, and two-dimensional vessel diameter variations. Significant variations in these functional indexes with age were found that should be taken into account in clinical practice. At lower ages, steeper and shorter pulsed-wave Doppler peak velocity and limited pulsatility should be expected as physiologic findings.

Nomograms for echocardiographic right ventricular sub-costal view dimensions in healthy Caucasian children: A new approach to measure the right ventricle

BACKGROUND

The sub-costal examination of the heart is part of routine examination in pediatric echocardiography, and has the advantage to visualize also the infundibulum part of the right ventricle (RV). Despite this fact, currently nomograms for sub-costal RV dimensions are lacking.

METHODS

We prospectively studied healthy Caucasian Italian children by two-dimensional echocardiography. Measurements included: sub-costal end diastolic basal-apical and latero-lateral diameters, end diastolic and end systolic area, 4 chamber end diastolic and end systolic area and length, end diastolic basal (RV1) and mid-cavity (RV2) diameters. Age, weight, height, heart rate (HR), and body surface area (BSA) were used as independent variables in different analyses to predict the mean values of each measurement. Structured Z scores were then computed. Agreement of RV diameters and areas in subcostal view and 4-chamber view were investigated.

RESULTS

732 subjects (age 0 days-17 years; 48% female; BSA 0.12-2.12 m2) were studied. The Haycock formula was used when presenting data as predicted values (mean ± 2 SDs) for a given BSA and within equations relating echocardiographic measurements to BSA. The predicted values and Z-score boundaries for all measurements are presented. Excellent correlations were found among two-dimensional diameters and area calculated in sub-costal view with those evaluated in 4-chamber view.

CONCLUSIONS

We report echocardiographic nomograms for RV diameters and areas measured in the sub-costal view. Our data may implement normative data for 2D echocardiography evaluation of the RV in children.

Review and status report of pediatric left ventricular systolic strain and strain rate nomograms

Interest in strain (ε) and strain rate (SR) for the assessment of pediatric left ventricular (LV) myocardial function has increased. However, the strengths and limitations of published pediatric nomograms have not been critically evaluated. A literature search was conducted accessing the National Library of Medicine using the keywords myocardial velocity, strain, strain rate, pediatric, reference values, and nomograms. Adding the following keywords, the results were further refined: neonates, infants, adolescents, range/intervals, and speckle tracking. Ten published studies evaluating myocardial velocities, ε, or SR nomograms were analyzed. Sample sizes were limited in most of these studies, particularly in terms of neonates. Heterogeneous methods-tissue Doppler imaging, two- and three-dimensional speckle tracking-were used to perform and normalize measurements. Although most studies adjusted measurements for age, classification by specific age subgroups varied. Few studies addressed the relationships of ε and SR measurements to body size and heart rate. Data have been generally expressed by mean values and standard deviations; Z scores and percentiles that are commonly employed for pediatric echocardiographic quantification have been never used. Reference values for ε and SR were found to be reproducible in older children; however, they varied significantly in neonates and infants. Pediatric nomograms for LV ε and SR are limited by (a) small sample sizes, (b) inconsistent methodology used for derivation and normalization, and (c) scarcity of neonatal data. Some of the studies demonstrate reproducible patterns for systolic deformation in older children. There is need for comprehensive nomograms of myocardial ε and SR involving a large population of normal children obtained using standardized methodology.

Strengths and Limitations of Current Adult Nomograms for the Aorta Obtained by Noninvasive Cardiovascular Imaging

Normalized measurements for the evaluation of aortic disease severity are preferred to the adoption of generic cutoff values. The purpose of this review is to evaluate the strengths and limitations of currently available aortic nomograms by echocardiography, computed tomography (CT), and magnetic resonance imaging (MRI). A literature search was conducted accessing the National Library of Medicine using the keywords normal values, aorta, echocardiography, CT, and MRI. Addition of these keywords further refined the results: reference values, nomograms, aortic arch, and adults. Thirty studies were included in the final analysis. Despite the strengths noted in the recent investigations, multiple methodological and numerical limitations emerged. The numerical limitations included sample size limitation in most of the studies (only few investigations consisted of >800 subjects and many had 70-300), lack of aortic arch measurements, and paucity of data for non-Caucasian subjects. Methodological limitations consisted of lack of standardization in measurements (systole vs. diastole, internal vs. external border, axial vs. orthogonal planes), heterogeneity and data normalization issues (various age intervals used, body size often not evaluated, data expressed as observed values rather than estimated values by z-score), and study design issues. The designs were mostly retrospective with poorly defined inclusion and exclusion criteria. The nomograms presented range of normality with significant differences, but also with some reproducible pattern. Despite recent advances, multiple methodological or numerical limitations exist in adult nomograms for the aorta. Comprehensive nomograms of aortic dimensions at multiple levels including the aortic arch for different imaging techniques, involving a wide sample size, and using standardized methodology for measurements and data normalization are warranted. The availability of robust nomograms may encourage the use of personalized rather than generic cutoff values.

Custodiol Solution and Cold Blood Cardioplegia in Arterial Switch Operation: Retrospective Analysis in a Single Center

BACKGROUND

The cardioplegia is one of the most significant tools used to increase myocardial protection. The aim of our study is to compare the use of Custodiol solution versus intermitted blood cardioplegia in a retrospective analysis of data for patients who underwent arterial switch operation in our institution.

MATERIAL AND METHODS

From January 2008 to March 2011, myocardial protection was performed in 44 neonates (blood group) with intermittent blood cardioplegia. From March 2011 to November 2014, myocardial protection was performed in 50 neonates (Custodiol group) with one-shot anterograde Custodiol cardioplegia.

RESULTS

Cardiopulmonary bypass and aortic cross-clamp were more favorable in Custodiol group (p-value 0.005 and ≤ 0.00001). The rate of delayed sternal closure was 63.6% in the blood group and 52% in the Custodiol group (p = 0.25). In the postoperative outcomes we did not find differences between the two groups. The 30-day mortality was one patient in the blood group (p = 0.46). We observed a transient ischemic electrocardiogram in 10 patients of the blood group and in 14 of the Custodiol group (p = 0.72), all cases with full resolution during hospitalization without coronary reoperation. A trend of higher peak of troponin-I and brain natriuretic peptide in Custodiol group has been reported.

CONCLUSION

No prefect cardioplegia exists, the Custodiol solution does not cause extra/additional myocardial damage in arterial switch operation. In our experience this strategy seems warranted to simplify the procedure and to be more comfortable for the surgeon.

Nomograms for mitral inflow Doppler and tissue Doppler velocities in Caucasian children

BACKGROUND

Pediatric echocardiographic nomograms for systolic/diastolic functional indices are limited by small sample size and inconsistent methodologies. Our aim was to establish pediatric nomograms for mitral valve (MV) pulsed wave Doppler (PWD) and tissue Doppler imaging (TDI) velocities.

METHODS

We performed PWD/TDI measurements of MV velocities and generated models testing for linear/logarithmic/exponential/square root relationships. Heteroscedasticity was accounted for by White test or Breusch-Pagan test. Age, weight, height, heart rate (HR), and body surface area (BSA) were used as independent variables in different analyses to predict the mean values of each measurement.

RESULTS

In all, 904 Caucasian Italian healthy children (age 0 days-17 years; 45.5% females; BSA 0.12-2.12m(2)) were prospectively studied. No individual variable provided equations with an acceptable coefficient of determination (R(2)) and even the inclusion of multiple variables in the model resulted in only a partial amelioration of the R(2). Higher R(2) were obtained for PWD-E deceleration time (0.53), septal (Se') and lateral (Le') MV-TDI e' velocity (Se': 0.54; Le': 0.55). Variability was higher at lower age and BSA. In older children patterns were more reproducible; however, the exclusion of neonates did not substantially improve the final models. The low R(2) hampered building of z-scores and calculation of estimated percentiles. Thus normative data have been presented as observed percentile according to age for all measurements.

CONCLUSIONS

We report normal ranges for PWD and TDI mitral velocities derived from a large population of Caucasian children. Variability of diastolic patterns especially at lower ages needs to be taken into account.