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Aims There are significant variations in the published normal values of two-dimensional speckle tracking–derived strain and strain rate. These occur even when authors use the same software. To measure strain, the operator creates a region of interest (ROI) to define the myocardium to be analyzed. The purpose of this study was to test the hypothesis that measurements vary significantly with the chosen ROI width. Methods and Results In 20 healthy subjects (11 males, mean age 17.6 ± 6.18 years) an apical four-chamber view (4CH) and parasternal short-axis view (SAX) were analyzed. Initially ROI width was set automatically by the software. Two subsequent measurements were obtained from each cine loop by choosing the ROI width one step narrower and one step wider than the automatic ROI width. The mean differences between the measurements of narrower and automatic ROI and between automatic and wider ROI were −1.8 ± 0.7% and −0.9 ± 0.5% for global longitudinal strain (SL), −2.2 ± 0.6% and −1.7 ± 0.7% for global circumferential strain (SC), −0.10 ± 0.06/sec and −0.07 ± 0.06/sec for global longitudinal strain rate (SrL), and −0.15 ± 0.09/sec and −0.12 ± 0.07/sec for global circumferential strain rate (SrC) (all P

Objective: The development of the left cardiac structures in the early life of small for gestational age (SGA) preterm infants has been inadequately studied. The aim of the study was to compare the left ventricular cardiac dimensions between SGA and appropriate for gestational age (AGA) preterm infants. Methods: Echocardiography was performed on day 2 (T1) and at age 1 month (T2) in 19 SGA preterm infants (birthweight rd percentile) and 21 AGA controls (P25-50) matched for gestational age ( Results: The left ventricular cardiac dimensions did not differ significantly between SGA and AGA infants at either T1 or T2 after correction for body length. The left ventricular mass was similar for SGA and AGA infants at T1 and T2 after correction for body weight or body length. The left ventricular output increased significantly from T1 to T2 in both SGA and AGA infants [SGA: 350 (T1)–640 (T2) mL/kg/min, P Conclusions: The left cardiac structures related to body length are comparable between SGA and AGA preterm infants in the first month of life and show similar development.

To study the impact of the maturational process of diastolic left ventricular function on trans-mitral Doppler flow parameters. In a survey we examined pulsed-wave Doppler signals and diastolic time intervals from 238 healthy neonates and infants. Using multiple linear regression analysis, we evaluated the impact of physiological determinants on parameter expression. Early-filling and atrial-filling peak velocities, early-filling acceleration and deceleration rates, and the atrial-filling time velocity integral reached a climax within 2 months after birth, while early-filling time velocity integral followed increasing throughout the study period. The isovolumic relaxation time was found to be significantly longer for neonates than for infants older than 2 months. The observed parameter movements could be attributed to changes of stroke volume and mitral valve area for early filling-time velocity integral (R2 = 0.93), and of heart rate, stroke volume, and mitral valve area for early filling peak velocity (R2 = 0.84), and atrial-filling time velocity integral (R2 = 0.65). Isovolumic relaxation time and atrial-filling peak velocity became heart rate dependent not before 3 months after birth. The observed parameter changes are powerful indicators for the maturational process in diastolic function. This process is mainly completed by 3 months of age.

Objectives In preterm infants, postnatal myocardial adaptation may be complicated by bronchopulmonary dysplasia (BPD). We aimed to describe the development of left ventricular function by serial 2D, Doppler, and speckle tracking echocardiography (2D-STE) in infants with and without BPD during the neonatal period and compare these to anthropometric and conventional hemodynamic parameters. Study Design Prospective echocardiography on day of life (DOL) 1, 7, 14, and 28 in 119 preterm infants 10%) were seen for the apical segment. While anthropometric parameters show rapid development during the first 4 weeks of life, the speckle tracking parameters did not differ statistically significantly during the neonatal period. Infants with and without BPD differed significantly (p

Background: Preterm infants may have cardiac stress related to patent ductus arteriosus (PDA) or bron-chopulmonary dysplasia (BPD). In this study, we examined the development of cardiac function in pre-term infants by measuring tissue Doppler–derived peak systolic strain (PSS) and strain rate (PSSR) in thefirst 28 days of life. Methods: Peak systolic strain and strain rate were measured in series in the free wallof the right (RV) and left (LV) ventricles on days 1, 7, 14, and 28 of life in 119 preterm infants

Aims To assess the effects of region of interest (ROI) size and strain length (SL) on the quality of analysis and to determine the feasibility and reproducibility of tissue Doppler–derived cardiac strain (S) and strain rate (SR) measurements for preterm infants

To assess the prevalence and detection rate of major anomalies (MAs) by applying first trimester anomaly scan (FTAS) including first trimester fetal echocardiography (FTFE) to all fetuses and discuss ethical implications.The study group included 6879 consecutive fetuses with known outcome of pregnancy (follow-up: 98%), 6565 with 'normal' nuchal translucency (NT) (≤ P95), 314 with 'increased' NT (P95). All fetuses received FTAS/FTFE. As MAs with the potential of being detected at FTAS/FTFE, we defined anomalies present at conception or developed during first trimester.Prevalence of MAs in fetuses with 'normal' NT reached 1.7%. Although 29.8% of chromosomal abnormalities were found in the group of 'normal' NT, 77% of MAs accompanied by a normal karyotype were found in this group. In fetuses with 'normal' NT and MA, diagnosis was made prenatally in 87.4% (FTAS/FTFE: 58.6%).A relevant number of MA is present in fetuses with 'normal' NT. More than half will be detected by FTAS/FTFE. As consequence, one should discuss a concept in which also in fetuses with 'normal' NT, FTAS/FTFE should be offered. This concept can also be justified from an ethical point of view, which focuses on the principles of nonmaleficence, justice and respect for autonomy of the pregnant woman.

The aim of this study was to investigate the degree of myocardial injury following catheter radiofrequency (RF) ablation (RFA) or cryoablation and its clinical significance in children and patients with congenital heart disease. Cardiac troponin T (cTnT) or cardiac troponin I (cTnI), creatine kinase (CK), and its cardiac isoenzyme MB (CK-MB) were measured in 269 patients who underwent catheter ablation (216 RFA, 53 cryoablation) just before the procedure and again 6 hours after the end of the procedure. Follow-up studies included echocardiography and 12 lead electrocardiographics (ECGs). No clinical, ECG, nor ECG signs of ischemia were detected. Biomarkers were increased in 57.7–75.5 %. A linear regression analysis illustrated the ablation target site and the number of RF applications as a function of higher cTnI and cTnT levels, with the maximum increase due to ventricular ablation and higher numbers of RF applications. No significant difference in cTnT levels after RFA or cryoablation were observed for AV nodal reentrant tachycardia procedures and no significant differences were observed after nonirrigated tip or irrigated tip RFA in atrial wall or ventricular wall ablation. Elevations in both troponin T and troponin I levels were commonly observed after ablation, especially in ventricular wall ablation as well as with increasing numbers of radiofrequency applications. However, unlike in patients with acute coronary syndrome, these elevated levels had no specific significance. Reference values for each ablation target site were proposed in order to potentially detect additional subclinical injuries to the coronary arteries.

Anorexia nervosa (AN) is an eating disorder with somatic complications. The aim of the study was to analyse echocardiographic abnormalities in patients with AN at initial examination and after weight restoration. A total of 173 consecutively admitted adolescents (aged 12-17 years), diagnosed with DSM-IV AN (307.1) were evaluated in a child and adolescent psychiatric department of a major university hospital from December 1997 to August 2008. In addition, 40 healthy adolescents of the same age with normal weight were examined. In patients with AN, 34.7% had a pericardial effusion (PE) which was clinically silent. In contrast, none of the controls presented with PE (p < 0.001). No differences across AN subtypes were observed. Patients with PE showed significantly lower body mass index (BMI) (p = 0.016) than patients without PE. They had more prominent low-T3 syndrome (p = 0.003) and longer duration of hospitalisation (p = 0.008) after controlling for BMI at admission. Remission of PE was observed in 88% of the patients after weight restoration. Left ventricular end-diastolic and end-systolic dimensions in AN were significantly lower than in controls (p < 0.001). There were no differences in interventricular septum thickness, posterior wall thickness and fractional shortening. This report indicates that adolescents with AN show cardiac abnormalities in comparison to healthy young women. Furthermore, PE is a frequent cardiac complication in patients with AN and it is associated with BMI, low T3 serum levels and duration of hospitalisation.

Although most Doppler-derived left ventricular diastolic function parameters undergo permanent changes during growth and maturation, isovolumic relaxation time (IVRT) normalized to heart rate has a constant value from the fourth month of life through adolescence. No reference values exist for IVRT in babies less than 3 months of age. However, this is the period when the most profound maturational changes in diastolic ventricular function are observed. To fill this gap, we conducted a survey with echocardiographic examinations concentrating primarily on the measurement of diastolic time intervals in 75 healthy term neonates and infants of up to 3 months of age (Table). These infants were either term newborns during their stay in the hospital after birth or scheduled patients referred to our outpatient department for the clearing of innocent heart murmurs. All patients had an uneventful history and physical examination, normal electrocardiogram findings, blood pressure within normal limits, and underwent a complete echocardiographic examination of the heart and the great vessels. We used 7.5to 5-MHz transducers on commercially available systems (77020AC, Hewlett Packard, and Sonos 1500, Hewlett Packard Medical Systems Inc, Andover, Mass). We derived IVRT and early filling acceleration time exclusively from pulsed wave Doppler shift signals, following the method described in a previous article. Differences between age groups were verified by the Kruskal-Wallis signed rank test and interactions between variables were tested by 1-way analysis of variance. The observer reliability of IVRT measurements was calculated from 20 randomly selected data sets. Correlation coefficients were good with R 0.96 for intraobserver and R 0.92 for interobserver vari

In very low birth weight neonates, a left-to-right shunt via persistent ductus arteriosus (PDA) may interact with diastolic left ventricular function, but specific changes of Doppler parameters have yet to be reported. In a serial transmitral Doppler study, we investigated the impact of a PDA on diastolic function parameters. Twenty-two patients with and without PDA were examined on day 3.8+/-1 and day 14+/-2 after birth. By the first examination, 13 out of 22 patients had a PDA; by the second examination, the number was still 8 out of 22. Peak early and atrial flow velocities (44.8+/-15 and 50.1+/-13 cm/s, respectively) were higher (p

Transmitral flow parameters in preterm and term infants were compared in order to study differences in signal expression and temporal dynamics of left ventricular diastolic function. In 63 preterm infants between 26 and 33 weeks of gestation and 102 term infants, a Doppler survey was performed during 6 months after birth. Early and atrial filling-time velocity integrals and peak velocities were significantly lower in the preterm neonates. Atrial filling parameters reached the level observed in term infants by 2 months of age. Peak early filling velocity was still lower for 2-month-old preterms and attained the term infants' level by 3 months of age. Preterm infants continued having high atrial filling fraction (AFF) (0.51+/-0.07) during 2 months after birth, while in term infants the fraction decreased continuously from 0.41+/-0.06 to 0.37+/-0.05. Isovolumic relaxation time (IVRT) was the only parameter without differences between preterm and term infants, and it decreased from 54+/-7 ms in neonates to 41+/-4 ms over 3 months. Stroke volume passing the mitral valve doubled in preterm (4+/-1 to 7.9+/-1.5 ml/cm2), but increased by only 37% (6.9+/-1.6 to 9.5+/-2.2 ml/cm2) in term infants. Our observations show that the maturational period of diastolic function appears prolonged in preterm infants. As preterm infants have to cope with a higher physiologic preload augmentation during growth, part of the delay in parameter changes might be caused by preload stress rather than by persistence of functional impairment. Although doing well under physiological conditions, preterm neonates may be at higher risk for diastolic dysfunction than term infants when an additional preload challenge is encountered.

Isovolumic relaxation time (IVRT) is a valuable adjunct to Doppler flow signals measured at mitral valve level for proper interpretation of left-ventricular diastolic performance. Few data exist on reference values in the pediatric age group. Moreover, routine evaluation of IVRT in patients with limited cooperation ability is impeded by the common technique of simultaneous phono and Doppler shift measurements. To overcome these disadvantages, the IVRT measurements presented are exclusively derived from Doppler shift signals. We set up reference values and investigated the influence of heart rate on that parameter. In 143 healthy participants aged 3 months through 19 years, a complete cardiologic examination was performed in the final evaluation of heart murmurs. We used a Hewlett Packard system 77020AC (Andover, Mass) and 5-, 3.5-, or 2.5-MHz transducers. A total of 63 data sets from a previous study on early and atrial Doppler flow parameters were introduced to this study. IVRT was measured from an apical 4-chamber view, positioning the pulsed wave Doppler sample volume in the left ventricle as much deviated from mitral inflow to left-ventricular outflow so as to visualize, sequentially, both the cessation of aortic outflow and the offspring of mitral flow from the Doppler shift 0 line (Figure 1). Low wall filtering is crucial for this technique. Continuous wave Doppler may be used for IVRT measurements alone, but for inflow measurements continuous wave Doppler is not appropriate. Paper speed was 100 mm/s and the signals were stored on videotape for offline evaluation. Reference values were derived from the mean of measurements in 6 consecutive heart cycles. In addition, we corrected the absolute values of IVRT for heart rate by dividing the absolute value by the square root of cardiac cycle length. Statistical analysis was performed using software (SPSS 9.0, Chicago, Ill). Median values and commercial percentiles for IVRT, and mean and SD for heart rate-corrected IVRT and heart rate were calculated. The influence of heart rate on IVRT was tested by univariate analysis of variance. Informed consent was obtained from the patients or their parents, and the study and local ethics committees approved the study. IVRT has its lowest absolute value during infancy to early childhood and then gradually advances with growth to a level known from investigations in adults (Figure 2). Normalizing the absolute values to cycle length disclosed a powerful inverse correlation between heart rate and IVRT (analysis of variance, R 0.64, P .001), which is in accordance with previous reports. By this correction it was possible to calculate a single reference value of 63 7 milliseconds for all patients in the pediatric age group besides newborns and infants in the second month of life (Figure 3). Measurement reproducibility tested in 20 randomly selected data sets was excellent with R 0.94 for intraobserver variability and R 0.92 for interobserver variability. Both data acquisition exclusively using Doppler shift signals and the ability of working with a single reference value is of major advantage and facilitates substantially the use of IVRT measurements as a routine parameter in echocardiographic examinations in children.

Prolonged and/or fractionated depolarization due to tissue degeneration of the ventricular myocardium is a feature of cardiomyopathy. Signal averaged electrocardiography uses high-pass filters of the Butterworth type to quantify, noninvasively, fractionated high-frequency components at the end of the QRS complex. In this study a finite impulse response high-pass filter of the 90th order (cutoff at 37 Hz) was applied to magnetocardiograms (MCGs) and high-resolution electrocardiograms (ECGs) order to quantify high-frequency components throughout the myocardial depolarization. Additionally, late-potential analysis on the signal-averaged ECG was performed. A prospective investigation was made of 23 cardiologically asymptomatic patients, 11 females and 12 males, with type I diabetes mellitus. Their mean age was 21.7 years (range, 13-34 years). The mean duration of diabetes was 14 years (range, 1-27 years). Data were compared with those of 22 control subjects (12 females, 10 males) of mean age, 23.2 years (range, 11-35 years). The ECGs and MCGs were simultaneously recorded and signal-averaged, digitally filtered, and quantified by a score obtained by multiplying the amplitude variation of the signal by the number of maximal/minimal in the QRS complex. Echocardiograms were used to calculate the left ventricular mass and to document the presence of cardiomyopathy. Scores were higher in the MCGs of with type I diabetes mellitus than in the control subjects (P < .001). High scores correlated with an increased left ventricular muscular mass index (P < .05) and duration of the diabetes (P < .05). The high-resolution ECG, processed analogously, showed similar results in relation to left ventricular mass (P = .06) and duration of diabetes (P = .07), respectively (nonsignificant). No late potentials were found. These findings suggest that using a linear-phase high-pass finite impulse response filter may be useful for the noninvasive identification of patients with cardiomyopathy who exhibit possible disturbances of intraventricular depolarization. Our findings also suggest that analysis using the total QRS complex, rather than the final part of the QRS complex only, may improve identification of patients at risk.

Signals from 37 magnetocardiographic sensors and simultaneously recorded 32 ECG leads were obtained in three healthy male subjects (including two reinvestigations). After recordings at rest, the heart rate was increased by pharmacologic stress (117 to 142 beats/min). Comparison of the repolarization of rest and stress showed substantial changes in the magnetocardiogram (MCG) up to T wave inversions during stress. In the ECG only junctional ST-T segment shifts were present. For quantification, correlation coefficients between pairs of rest and stress MCG and rest and stress ECG distributions were calculated for the same time instant at the beginning of T wave under rest and stress conditions. In addition, equivalent electrical current dipole moment and magnetic dipole moment vectors were calculated from the MCG, and their change from rest to stress evaluated. Correlation coefficients for MCG comparison ranged from 0.3 to 0.5; ECG comparison suggested much less change from stress, ranging from 0.7 to 1.0. Current dipole moment changes at T wave onset were marginal; in contrast, the magnetic dipole moment changed substantially. Since the magnetic dipole reflects vortex currents, changes in its intensity and/or orientation during repolarization suggest this as the biophysical basis of the striking difference in the response of the MCG and ECG to pharmacologic stress. Normal ECG findings at rest and under stress in healthy subjects support the conclusion that the repolarization changes in the MCG were of nonpathologic origin.

Summary Open lung biopsy is performed in patients with congenital heart disease to determine the suitability for surgical correction. Controversy exists as to whether arterial density can be graded with certainty. We studied the influence on the grading (Heath-Edwards) of two morphometric techniques. Lung tissue from 14 controls and biopsy specimens from 80 patients with atrial septal defect (n=10), ventricular septal defect (n=27), complete atrioventricular canal (n=27), miscellaneous lesions (n=8) and tetralogy of Fallot (n=8) were analyzed with a planimetric method. Additionally, wall thickness was determined in 52 patients by distance measurements. The ratio of alveoli/arteries per area of lung tissue was measured. Medial thickness was “increased” on distance measurements in 15% of the cases where planimetric data showed normal wall thickness. The ratio of alveoli/arteries varied up to 43% from the mean. Hemodynamic data obtained at a median (range) time of 2 months (1 day to 18 months) before the operation did not correlate with morphologic findings. In 27 patients hemodynamic data were recorded at a median time of 1 year (3 days to 44 months) after the operation. Intimal fibrosis occupying more than 1 0% of the vessel lumen was associated with persistent high pulmonary vascular resistance. We conclude that morphometric techniques are useful to determine the degree of fibrosis in advanced vascular lesions. Arterial density cannot be determined in biopsy specimens with adequate certainty.

Endothelin-1 (ET-1) has been implicated in the pathogenesis of pulmonary vascular disease in patients with congenital heart disease. We studied the effect of pulmonary blood flow on plasma ET-1 concentrations. Systemic venous, pulmonary arterial, and pulmonary venous blood samples were obtained from 40 patients with atrial septal defect II (n = 21), ventricular septal defect (n = 10), persistent ductus arteriosus (n = 6), and complete (n = 2) and partial (n = 1) atrioventricular canal at cardiac catheterization and analyzed by radioimmunoassay. Median age (range) was 5.2 years (8 months to 66 years), and the resistance ratio ( Rp Rs ) was 0.08 (0.03 to 0.67). Pulmonary vein to pulmonary artery ET-1 ratio in patients with “high flow” ( n = 26, Qp Qs ≥ 1.5 ; ET-1 ratio = 0.8) did not differ from those with “low flow” ( n = 14, Qp Qs ; ET-1 ratio = 1.0). We conclude that an increase in pulmonary blood flow alone does not result in an increase in plasma ET-1.

Long-term variability (LTV) of heart rate was calculated continuously by a microprocessor in 25 preterm infants undergoing indomethacin treatment for closure of patent ductus arteriosus (PDA), in 24 preterm infants without signs of PDA, and in 10 neonates treated with prostaglandin E1 for cyanotic heart malformation. In infants with patent ductus arteriosus, LTV was lower than in controls. Following indomethacin, LTV increased most markedly (from 1.5 to 3.2; p < 0.01) in infants with improved ventilation. The increase was less marked (from 1.8 to 2.5; p < 0.05) in infants whose degree of respiratory failure did not change. LTV remained largely unchanged in infants who deteriorated. In 9 out of the 10 neonates treated with prostaglandin E1, LTV increased. We conclude that LTV corresponds to brain stem oxygenation and may be a useful tool to monitor treatment of PDA.

Three patients with pacemaker interactive drug resistant tachycardia underwent invasive electrophysiological studies. In the first patient, the retrograde conduction of the artificial reciprocating tachycardia was provided by two right-sided accessory pathways and the antegrade conduction by an atrial synchronous pulse generator. In addition, AV-nodal tachycardia occurred alternately. In the second patient with intermittent atrial flutter, the AV node and, coincidentally, an AV sequential pulse generator provided high-rate antegrade conduction to the ventricles. In the third patient with surgical complete heart block, intermittent AV-nodal tachycardia induced retrograde atrial activation while an atrial synchronous pacemaker provided the antegrade conduction. Electrode catheter exploration of the heart allowed localization and closed-chest ablation of the accessory pathways or AV node by delivering two to seven 200-joule direct-current shocks through the appropriate electrode of the exploring catheter. Thereby, pacemaker-mediated arrhythmias could be controlled in these patients in the follow-up of 6 to 8 months.

Objectives. The aim of this study was to set up reference values for Doppler flow-derived left ventricular filling parameters and to evaluate physiologic determinants of changes in signal expression related to maturation.Background. In left ventricular diastolic function studies, age-related modulations in signal expression are observed. Assuming degenerative myocardial changes to be absent during childhood and adolescence, the determinants of these modulations must be different from those suspected in adults.Methods. Pulsed wave Doppler signals from the mitral valve tip region were recorded in 329 healthy subjects aged 2 months to 39 years. Multiple linear regression was used to evaluate statistical relations between Doppler flow signals and stroke volume in the mitral valve area.Results. Increasing early filling time velocity integral throughout maturation caused a decrease in atrial filling fraction from 0.34 ± 0.06 to 0.24 ± 0.04 (p < 0.005). Peak flow velocities during atrial systole decreased from infancy to adolescence (66 ± 15 to 41 ± 10 cm/s). Main effects on signal modulation were caused by heart rate, stroke volume and mitral ring area with a linear model fit (R2) of 0.79 for early filling phase (E)-time velocity integral, 0.6 for atrial filling phase peak velocity 0.84 for total E duration and 0.73 for E deceleration time. Atrial filling phase-time velocity integral, albeit significantly dependent on heart rate, was stable throughout growth.Conclusions. During infancy and childhood, the stroke volume crossing the mitral valve is a main modulator for early filling phase (E)-time velocity integral and diastolic time intervals during early filling, whereas atrial filling phase parameters are mainly dependent on heart rate. This results in a more pronounced atrial filling during infancy and childhood.

22Na and 36Cl fluxes in isolated human cornea preparations were measured under short-circuited conditions. At pH 7.3-PH 7.6 sodium net flux was directed from aqueous humour to tear side, chloride net flux was statistically not different from zero. Alkalinization of the bathing solution to pH 8.6 stimulated unidirectional sodium and chloride fluxes from aqueous humour to tear side resulting in net sodium and chloride fluxes towards the tear side which both were statistically different from zero. Cyclic AMP (10(-3) M) was found to stimulate sodium and chloride unidirectional fluxes from aqueous humour to tear side, thus leading to significant net sodium and chloride fluxes in the same direction. Epinephrine (10(-4) M) increased the unidirectional chloride flux from aqueous humour to tear side more pronounced than in the opposite direction, producing a significant net chloride flux towards the tear side. The results are consistent with the hypothesis that the electrolyte pumps may under certain conditions contribute to the dehydration of the stroma.