Myocardial performance index in active and inactive paediatric systemic lupus erythematosus.

OBJECTIVES: To evaluate cardiac structure and function in paediatric SLE patients without clinical evidence of cardiovascular disease in active and inactive diseases. METHODS: Patients aged ≤20 years who fulfilled the diagnostic criteria of active SLE underwent transthoracic echocardiography to evaluate cardiac structure and function, and were then followed up echocardiographically every 3-4 months until SLE disease was inactive. Patients with heart failure, myocarditis, pericarditis, endocarditis, coronary artery disease, or abnormal structural heart disease were excluded. RESULTS: Twenty-six active SLE patients, mean age 13.2±3.3 years, of whom 20 were female (77%), were enrolled. Most patients had cardiac abnormalities especially LV global dysfunction assessed by left ventricular myocardial performance index (LV MPI). LV MPI by conventional method, by tissue Doppler imaging (TDI) at medial and lateral mitral valve annulus were significantly decreased when compared to LV MPI in patients with inactive disease (0.44±0.14 vs. 0.30±0.05, 0.52±0.09 vs. 0.36±0.04, and 0.51±0.09 vs. 0.35±0.05, p<0.001). Using receiver operating characteristic, LV MPI cut-off at 0.37, 0.40, and 0.40 by conventional, medial TDI, lateral TDI had sensitivity and specificity of 90% and 84%, 90% and 96%, 90% and100%, respectively. CONCLUSIONS: Left ventricular global dysfunction was found to be common in paediatric patients with active SLE. LV MPI by TDI might be useful to diagnose active SLE in paediatric patients.

Ultrasound Versus Traditional Palpation to Guide Radial Artery Cannulation in Critically Ill Children: A Randomized Trial.

OBJECTIVES: To identify success rates for radial artery cannulation in a pediatric critical care unit using either palpation or ultrasound guidance to cannulate the radial artery. METHODS: A prospective randomized comparative study of critically ill children who required invasive monitoring in a tertiary referral center was conducted. All patients were randomized by a stratified block of 4 to either ultrasound-guided or traditional palpation radial artery cannulation. The primary outcomes were the first attempt and total success rates. RESULTS: Eighty-four children were enrolled, with 43 randomized to the palpation technique and 41 to the ultrasound-guided technique. Demographic data between the groups were not significantly different. The total success and first attempt rates for the ultrasound-guided group were significantly higher than those for the palpation group (success ratio, 2.03; 95% confidence interval, 1.13-3.64; P = .018; and success ratio, 4.18; 95% confidence interval, 1.57-11.14; P = .004, respectively). The median time to success for the ultrasound-guided group was significantly shorter than that for the palpation group (3.3 versus 10.4 minutes; P < .001). Cannulation complications were lower in the ultrasound-guided group than the palpation group (12.5% versus 53.3%; P < .001). CONCLUSIONS: The ultrasound-guided technique could improve the success rate and allow for faster cannulation of radial artery catheterization in critically ill children.

Intrapulmonary vascular dilation in children with chronic liver diseases: pre- and post-liver transplantation.

BACKGROUND AND STUDY AIMS: Chronic liver disease (CLD) can cause hepatopulmonary syndrome (HPS), defined as triad of liver disease, hypoxemia, and intrapulmonary vascular dilation (IPVD). The aim of this study was to determine the evidence of IPVD in a cohort of pediatric patients with CLD pre- and post-liver transplantation (LT). MATERIAL AND METHODS: All pediatric patients with CLD listed for LT were studied. Pulse oxygen saturation (SpO(2)), technetium-99m-labeled macroaggregated albumin ((99m)Tc- MAA) perfusión scan (positive test: uptake of the isotope ≥ 6% in the brain), and echocardiography with saline bubble test (SBT) were performed. SBT was re-evaluated at 3-6 months after LT. Grading of SBT included grade 0 (no bubble), I (1-9 bubbles), grade II (10-20 bubbles), and grade III (> 20 bubbles). RESULTS: Eighteen patients, median age 22.5 months (8-108), were enrolled. Most had biliary atresia (77.8%). Pre-LT, all patients had SpO(2) of 100% and none had positive (99)mTc- MAA perfusion scan. Two patients (11%) had negative SBT (grade 0), 1 (5.5%) had grade I, 3 (16.5%) had grade II, and 12 (67%) had grade III, respectively. Post-LT SBT became negative in all survivors (n = 16), (p = 0.0001). CONCLUSIONS: Most cirrhotic children in this cohort study had evidence of IPVD by positive SBT. However, none of these met the criteria for diagnosis of HPS. This evidence of IPVD subsided after LT.

Accuracy of bedside glucometry in critically ill children with peripheral hypoperfusion.

The accuracy of glucose test strip in critically care has been questioned. We investigated the accuracy of glucose test strip in critically ill children. Patients, aged from 1 month to 18 years admitted in pediatric intensive care unit. Demographic data, hemodynamic parameters, and perfusion index (PI) were recorded. Glucose test strips were performed from finger stick blood [capillary blood glucose (CBG)] and from whole blood [whole blood glucose (WBG)] along with laboratory plasma blood glucose (PBG) from either arterial or venous blood samples. The accuracy of glucose test strips was defined according to ISO 15197 and Clarke error grid (CEG). One hundred and eighty one blood samplings including 117 arterial blood (CBG, WBGa, PBGa) and 64 venous blood (CBG, WBGv, PBGv) were obtained. The accuracy of WBGa was 98.3 and 95.2% when compared to the accuracy of CBG (88.7 and 83.3%. The accuracy of WBGv was 92.2% and 87.0 when compared to the accuracy of CBG which was 79.7 and 72.9% (ISO 15197: 2003 and 2013, respectively). Bland-Altman plot demonstrated bias and precision of 7.4±17.7 mg/dL in acceptable PI group compared to 30.2±23.4 mg/dL in low PI group (PI≤0.3). The CBG test strip must be interpreted carefully in critically ill children. A low PI was associated with poor CBG strip accuracy. WBG test strip from arterial blood was more appropriate for glucose monitoring in children with peripheral hypoperfusion.

Non-invasive cardiac output assessment in critically ill paediatric patients.

OBJECTIVE: Recently, non-invasive methods for cardiac output (CO) assessment have been developed including the ultrasonic cardiac output monitor (USCOM). This technique uses the same concept as Doppler echocardiography but differs in two aspects including continuous wave (CW) Doppler and estimated outflow tract diameter (OTD) used in USCOM compared to pulsed wave Doppler and directed measurement of OTD used in echocardiography. We sought to assess the agreement between CO assessment by USCOM and echocardiography in critically ill paediatric patients. METHODS: Paired measurements of CO in critically ill paediatric patients were simultaneously and independently obtained by USCOM and echocardiography. Agreement between OTD, velocity time integral (VTI), CO, and cardiac index (CI) were assessed by percentage error and Bland-Altman analysis. RESULTS: Thirty-four children (aged 7.86 +/- 5.78years, 44.1% male) had a mean OTD (1.47 +/- 0.38, 1.41 +/- 0.40), VTI (19.13 +/- 6.06, 23.53 +/- 7.31 cm), CO (3.88 +/- 2.19,4.41 +/- 2.83 l/min) and CI (4.23 +/- 1.19,4.77 +/- 1.43 l/min/m2) by echocardiography and USCOM, respectively. Bias +/- precision and percentage of error of OTD, VTI, CO, and CI were -0.07 +/- 0.20 cm, 27.80%; -4.40 +/- 3.84 cm, 31.99%; -0.53 +/- 1.23 l/min, 54.66%; and 0.54 +/- 1.03 l/min/m2, 42.32%, respectively. The bias +/- precision and percentage error were more important in patients with septic shock (n = 16). CONCLUSION: USCOM was an unreliable tool for absolute value measurement of CO and CI due to the errors of VTI by CW Doppler.

N-terminal-pro-brain natriuretic peptide: a guide for early targeted indomethacin therapy for patent ductus arteriosus in preterm Infants.

AIM: To determine whether N-terminal-pro-brain natriuretic peptide (NT-proBNP) level could be an effective guide for early targeted indomethacin therapy for patent ductus arteriosus (PDA) in preterm infants. METHODS: An interventional study involved preterm infants, born at <33 weeks of gestation, who had plasma NT-proBNP levels obtained at day 2 of life. Indomethacin therapy was given if plasma NT-proBNP level was ≥10,180 pg/mL, the cut-off for predicting hemodynamic significant PDA (hsPDA). Echocardiograms were performed within 6 h at the time of plasma NT-proBNP collection and again at day 7, or whenever clinical hsPDA was suspected. Primary outcomes were the incidence of later hsPDA and unnecessary exposure rate to indomethacin. RESULTS: Fifty infants were enrolled. On day 2, 19 (38%) infants had plasma NT-proBNP above the cut-off and received indomethacin therapy; none of them developed later hsPDA, while 1 of 31 infants with NT-proBNP below the cut-off level developed clinical hsPDA. Unnecessary exposure to indomethacin occurred in two infants (11%). Overall, no enrolled infants had either reopening of ductus or PDA ligation. CONCLUSION: Using NT-proBNP level on day 2 as a guide for early targeted indomethacin therapy reduced later onset of hsPDA and the number of unnecessary exposures to indomethacin.

QT dispersion in childhood obstructive sleep apnoea syndrome.

The difference between maximal and minimal QT interval and corrected QT interval defined as QT dispersion and corrected QT dispersion may represent arrhythmogenic risks. This study sought to evaluate QT dispersion and corrected QT dispersion in childhood obstructive sleep apnoea syndrome. Forty-four children (34 male) with obstructive sleep apnoea syndrome, aged 6.2 plus or minus 3.5 years along with 38 healthy children (25 male), 6.6 plus or minus 2.1 years underwent electrocardiography to measure QT and RR intervals. Means QT dispersion and corrected QT dispersion were significantly higher in obstructive sleep apnoea syndrome than controls, 52 plus or minus 27 compared to 40 plus or minus 14 milliseconds (p equal to 0.014), and 71 plus or minus 29 compared to 57 plus or minus 19 milliseconds (p equal to 0.010), respectively. Interestingly, QT dispersion and corrected QT dispersion in obstructive sleep apnoea syndrome with obesity, 57 plus or minus 30 and 73 plus or minus 31 milliseconds, were significantly higher than in control, 40 plus or minus 14 and 57 plus or minus 19 milliseconds (p equal to 0.009 and 0.043, respectively). However, QT dispersion and corrected QT dispersion in obstructive sleep apnoea syndrome without obesity, 43 plus or minus 20 and 68 plus or minus 26 milliseconds, were not significantly different. In conclusion, QT dispersion and corrected QT dispersion were significantly increased only in childhood obstructive sleep apnoea syndrome with obesity. Obesity may be the factor affecting the increased QT dispersion and corrected QT dispersion.

Infection-associated hemophagocytic syndrome among patients with dengue shock syndrome and invasive aspergillosis: a case series and review of the literature.

The authors report four autopsy cases of previously healthy children with dengue shock syndrome complicated with infection-associated hemophagocytosis and invasive aspergillosis. Hemophagocytosis is confirmed by histopathology of autopsied reticuloendothelial organs. All four children were identified to have invasive aspergillosis by histopathology and three cases were positive on fungal culture for Aspergillus spp. Regarding the cause of death among the four children without pre-existing underlying disease, three cases were directly ascribable to invasive aspergillosis and the remaining case was ascribed to dengue shock syndrome. The transmigration of preexisting fungi from the respiratory mucosa damaged by the dengue shock process is postulated as the pathogenesis of invasive aspergillosis. The main predisposing factor was found to be prolonged dengue shock syndrome. We reviewed the clinicopathologic features and therapeutic management of infection-associated hemophagocytic syndrome in patients with dengue shock syndrome and invasive aspergillosis.

Pulmonary atresia and ventricular septal defect with collaterals to right lung associated with anomalous left pulmonary artery from the ascending aorta.

We present a 10-month-old boy with cyanosis. This is a rare case of pulmonary atresia, ventricular septal defect (VSD), major aorto-pulmonary collateral arteries (MAPCAs) to the right lung with absent native right pulmonary artery (RPA) in association with anomalous left pulmonary artery (LPA) from the ascending aorta (AAo). Echocardiography was unable to identify all of the cardiovascular abnormalities. Multidetector CT demonstrated all of these abnormalities and is the investigation of choice instead of cardiac catheterization.

P-wave dispersion as a simple tool for screening childhood obstructive sleep apnea syndrome.

INTRODUCTION: The gold standard for the diagnosis of childhood obstructive sleep apnea syndrome (OSAS) diagnosis is polysomnography; however, electrocardiography (ECG) may provide a simpler alternative. P-wave dispersion (PWD), the difference between the maximum and minimum P-wave duration measured by 12-lead ECG, is increased in adult OSAS but has not been researched in childhood OSAS. The aims of this study were to determine the PWD and cut-off value for the diagnosis of childhood OSAS and its association with severity. METHODS: A total of 77 children with confirmed OSAS and 44 control participants underwent surface 12-lead ECG. P-wave duration was measured using a digital caliper by a researcher blinded to the groups. RESULTS: Median (interquartile range) PWD in children with OSAS (median age = 82.8 months, range = 24-194 months) was significantly higher than that in the control group (median age = 73.4 months, range = 12-156 months): 38.3 (29.7-50.5) vs 25.5 (20.5-30.5) milliseconds, respectively (p < 0.0001). Subgroup analysis according to OSAS severity categorized by the apnea-hypopnea index from polysomnography demonstrated that PWD in the severe OSAS group (n = 24) was significantly higher than that in the mild-to-moderate OSAS group (n = 53): 48.5 (34.7-67.4) vs 35.5 (28.2-47.8) milliseconds, respectively (p = 0.006). A cut-off value of PWD at 26.5 ms from the receiver operating characteristic curve for the diagnosis showed the area under the curve to be 0.839, with a sensitivity of 89.6% and a specificity of 61.4%. CONCLUSION: PWD was significantly increased in children with OSAS, particularly in severe cases. PWD could be a useful tool for screening childhood OSAS.

A Randomized Controlled Trial of Immediate versus Delayed Umbilical Cord Clamping in Multiple-Birth Infants Born Preterm.

BACKGROUND: Delayed cord clamping (DCC) improves placental transfusion and increases blood volume in preterm infants when compared with immediate cord clamping (ICC). However, evidence to support DCC in multiple-birth preterm infants is still lacking. OBJECTIVE: To compare the outcomes of ICC versus DCC in preterm infants of multiple births. STUDY DESIGN: Women with a multiple pregnancy, including twins and triplets with a gestational age of 28-36 weeks, were randomized to receive ICC (23 women and 50 infants) or DCC for 30-60 s (24 and 51 infants). The infants' hematocrit on admission, superior vena cava (SVC) flow measured within 24 h, and hematocrit at 8 weeks of age were compared. The use of uterotonic agents during delivery was not controlled in this study. RESULT: All infants were delivered by cesarean section (CS) except for 2 sets of twins, 1 in each group. Maternal and infant baseline characteristics in both groups were comparable. There were no significant differences between the groups in admission hematocrit, SVC flow measured within 24 h, hematocrit at 8 weeks of age, or any other neonatal outcomes. The incidence of maternal postpartum hemorrhage (PPH) was higher in the DCC group (4.3% in ICC vs. 25% in DCC, p = 0.04). CONCLUSION: DCC for 30-60 s did not improve placental transfusion or increase systemic blood flow in multiple-birth infants born preterm, mostly by CS, when compared with ICC. The finding of a higher PPH rate in the DCC group raises concerns about the maternal safety of this procedure in this patient population.

Comparison of three non-invasive hemodynamic monitoring methods in critically ill children.

INTRODUCTION: Hemodynamic parameters measurements were widely conducted using pulmonary artery catheter (PAC) with thermodilution as a reference standard. Due to its technical difficulties in children, transthoracic echocardiography (TTE) has been widely employed instead. Nonetheless, TTE requires expertise and is time-consuming. Noninvasive cardiac output monitoring such as ultrasonic cardiac output monitor (USCOM) and electrical velocimetry (EV) can be performed rapidly with less expertise requirement. Presently, there are inconsistent evidences, variable precision, and reproducibility of EV, USCOM and TTE measurements. Our objective was to compare USCOM, EV and TTE in hemodynamic measurements in critically ill children. MATERIALS AND METHODS: This was a single center, prospective observational study in critically ill children. Children with congenital heart diseases and unstable hemodynamics were excluded. Simultaneous measurements of hemodynamic parameters were conducted using USCOM, EV, and TTE. Inter-rater reliability was determined. Bland-Altman plots were used to analyse agreement of assessed parameters. RESULTS: Analysis was performed in 121 patients with mean age of 4.9 years old and 56.2% of male population. Interrater reliability showed acceptable agreement in all measured parameters (stroke volume (SV), cardiac output (CO), velocity time integral (VTI), inotropy (INO), flow time corrected (FTC), aortic valve diameter (AV), systemic vascular resistance (SVR), and stroke volume variation (SVV); (Cronbach's alpha 0.76-0.98). Percentages of error in all parameters were acceptable by Bland-Altman analysis (9.2-28.8%) except SVR (30.8%) and SVV (257.1%). CONCLUSION: Three noninvasive methods might be used interchangeably in pediatric critical care settings with stable hemodynamics. Interpretation of SVV and SVR measurements must be done with prudence.

Cardiac dimensions and function in children with obesity.

BACKGROUND: Obesity can cause alterations in cardiac dimensions and function. Cardiac dysfunction during childhood may affect the quality of life in adulthood. This study evaluated left ventricular (LV) dimensions, systolic function and left ventricular myocardial performance index (LMPI) in children with obesity. METHODS AND RESULTS: Thirty-three obese children with mean age of 9.8 +/- 2.4 years, weight 61.3 +/- 20.8 kg, BMI 29.5 +/- 5.8 kg/m2 and percentage of actual weight to ideal body weight for height (%IBW) 170 +/- 25%, underwent echocardiography to assess LV dimensions, systolic and global functions. There were 2, 14 and 17 children with mild (160%IBW), respectively. The mean ratio of left ventricular end-diastolic dimension (LVEDD) to predicted LVEDD expressed in percentage (%LVEDD) was 98.3 +/- 7.8%, the left ventricular shortening fraction (LVFS) was 37.5 +/- 4.9% and the left ventricular ejection fraction (LVEF) was 67.5 +/- 5.9%. All were within normal range except that 2 children (6%) had mild LV dilatation. The mean LMPI was 0.35 +/- 0.08. However, 11 children (33%) had abnormal LMPI (>0.4). The severity of obese children did not correlate with the global LV dysfunction. CONCLUSION: The left ventricular dimensions and systolic function in children with obesity were essentially normal. LMPI which indicates LV global function was found to be abnormal in 33% of children with obesity and may be used to do early detection of LV global dysfunction.

Cardiac dimensions and function in children with obesity.

BACKGROUND: Obesity can cause alterations in cardiac dimensions and function, and cardiac dysfunction during childhood may affect the quality of life in adulthood. This study was done to evaluate left ventricular dimensions, systolic function, and the left ventricular myocardial performance index in children with obesity. MEHTODS AND RESULTS: Thirty-three obese children whose mean age was 9.8 +/- 2.4 years, weight was 61.3 +/- 20.8 kg, body mass index was 29.5 +/- 5.8 kg/m(2), and percentage of actual weight to ideal body weight for height (% IBW) was 170 +/- 25%, underwent echocardiography for the assessment of left ventricular dimensions, and systolic and global functions. There were 2, 14, and 17 children with mild (< 140% IBW), moderate (141-160% IBW), and severe obesity (> 160% IBW), respectively. The mean ratio of left ventricular end-diastolic dimension to predicted left ventricular end-diastolic dimension expressed in percentage was 98.3 +/- 7.8%, the left ventricular shortening fraction was 37.5 +/- 4.9%, and the left ventricular ejection fraction was 67.5 +/- 5.9%. All were within the normal range, with the exception of two children (6%) who had mild left ventricular dilatation. The mean left ventricular myocardial performance index was 0.35 +/- 0.08. However, 11 children (33%) had an abnormal index (< 0.4). The severity of obesity did not correlate with the global left ventricular dysfunction. CONCLUSION: The left ventricular dimensions and systolic function in children with obesity were essentially normal. The left ventricular myocardial performance index, which is an indicator for left ventricular global function, was found to be abnormal in 33% of the children, and may be used for the early detection of left ventricular global dysfunction.

Effects of Domperidone on QT Interval in Children with Gastroesophageal Reflux Disease.

BACKGROUND: Domperidone has been widely used in children with gastroesophageal reflux disease (GERD). Studies on the effects of domperidone on corrected QT interval (QTc) in young children are limited. Our aim was to study the effect of domperidone on the repolarization abnormalities assessed by electrocardiogram (ECG) in young children. METHODS: ECG was performed in children <2 years of age before and after taking domperidone orally 0.3 mg/kg three times/day for at least a 1 week period. Each ECG was reviewed and QT, RR, and Tpeak to Tend intervals (TpTe) were measured to calculate the QTc and TpTe/QT ratio. RESULTS: A total of 22 patients (12 male) with a median age of 8.5 months (1-24 months) were enrolled. Most patients (59.1%) were under 1 year of age. The median baseline QTc (410 milliseconds, 350-450 milliseconds) was not significantly different from the QTc after taking domperidone (410 milliseconds, 320-560 milliseconds), p = 0.159. Only two patients showed a QTc increase ≥450 milliseconds. The baseline TpTe interval and TpTe/QT (105 milliseconds, 60-170 milliseconds and 0.27 milliseconds, 0.15-0.43 milliseconds) were significantly greater than the TpTe interval and TpTe/QT in children after taking domperidone (90 milliseconds, 60-140 milliseconds and 0.22 milliseconds, 0.15-0.29 milliseconds), p = 0.001 and 0.004, respectively. CONCLUSIONS: Our data demonstrate that domperidone treatment over a short-term period in children <2 years of age did not lengthen QTc significantly; however, QTc increased ≥450 milliseconds in two patients with concomitant lansoprazole. Routine baseline and follow-up ECG may not be necessary in each individual case receiving only domperidone.

Improvement of Skills in Cardiopulmonary Resuscitation of Pediatric Residents by Recorded Video Feedbacks.

OBJECTIVE: To evaluate the pediatric residents' cardiopulmonary resuscitation (CPR) skills, and their improvements after recorded video feedbacks. METHODS: Pediatric residents from a university hospital were enrolled. The authors surveyed the level of pediatric resuscitation skill confidence by a questionnaire. Eight psychomotor skills were evaluated individually, including airway, bag-mask ventilation, pulse check, prompt starting and technique of chest compression, high quality CPR, tracheal intubation, intraosseous, and defibrillation. The mock code skills were also evaluated as a team using a high-fidelity mannequin simulator. All the participants attended a concise Pediatric Advanced Life Support (PALS) lecture, and received video-recorded feedback for one hour. They were re-evaluated 6 wk later in the same manner. RESULTS: Thirty-eight residents were enrolled. All the participants had a moderate to high level of confidence in their CPR skills. Over 50 % of participants had passed psychomotor skills, except the bag-mask ventilation and intraosseous skills. There was poor correlation between their confidence and passing the psychomotor skills test. After course feedback, the percentage of high quality CPR skill in the second course test was significantly improved (46 % to 92 %, p = 0.008). CONCLUSIONS: The pediatric resuscitation course should still remain in the pediatric resident curriculum and should be re-evaluated frequently. Video-recorded feedback on the pitfalls during individual CPR skills and mock code case scenarios could improve short-term psychomotor CPR skills and lead to higher quality CPR performance.

Cardiac abnormalities in cirrhotic children: pre- and post-liver transplantation.

BACKGROUND/AIM: Liver cirrhosis is associated with several cardiac abnormalities. There have been few studies of these abnormalities in cirrhotic children post-liver transplantation (LT). The purpose of this study was to evaluate cardiac abnormalities in cirrhotic children pre- and post-LT. METHODS: All cirrhotic children <15 years of age on a waiting list for LT underwent pre-LT echocardiography to evaluate left ventricular (LV) dimension, mass, and function. Repeated studies were performed at 1-2 and 3-6 months post-LT. RESULTS: A total of 20 cirrhotic children (median age 21.5 months [8-108 months], 11 female [55 %]) were enrolled in the study. Most patients had biliary atresia (75 %) and decompensated cirrhosis, with a median pediatric end-stage liver disease score of 19.5 (14-28). Two patients subsequently died, at 1 and 4 months post-LT. Echocardiography was re-evaluated in 17 and 18 patients at 1-2 months and 3-6 months post-LT, respectively. Prior to transplant, most patients had cardiac abnormalities, including LV enlargement (50 %), increased LV mass (95 %), abnormal LV geometry (95 %), hyperdynamic LV systolic function (60 %), LV diastolic dysfunction (60 %), and high cardiac index (75 %). At 3-6 months post-LT, no significant decrease in cardiac abnormalities was noted; however, cardiac parameters including LV dimension in diastole index and z-score, LV mass index, and relative wall thickness were significantly decreased. CONCLUSIONS: Most cirrhotic children had cardiac abnormalities, including LV enlargement, increased LV mass, abnormal LV geometry, and LV dysfunction. These abnormalities tended to improve post-LT. We suggest that echocardiography should be performed in all cirrhotic children.

Epinephrine-induced T-wave notching in congenital long QT syndrome.

OBJECTIVES: The purpose of this study was to characterize the effect of epinephrine on T-wave morphology in patients with congenital long QT syndrome (LQTS). BACKGROUND: QT prolongation is a paradoxical, LQT1-specific response to low-dose epinephrine infusion. At rest, notched T waves are more common in LQT2. METHODS: Thirty subjects with LQT1, 28 with LQT2, and 32 controls were studied using epinephrine provocation. Twelve-lead ECG was recorded continuously, and QT, QTc, and heart rate were obtained during each stage. Blinded to phenotype and genotype, T-wave morphology was classified as normal, biphasic, G1 (notch at or below the apex), or G2 (distinct protuberance above the apex). RESULTS: At baseline, 97% LQT1, 71% LQT2, and 94% control had normal T-wave profiles. During epinephrine infusion, G1- and G2-T waves were more common in LQT2 than in LQT1 (75% vs 26%, P = .009). However, epinephrine-induced G1-T waves were present in 34% of control. Epinephrine-precipitated biphasic T waves were observed similarly in all groups: LQT1 (6/30), LQT2 (3/28), and control (4/32). During low-dose epinephrine infusion (< or =0.05 microg/kg/min), G1-T waves occurred more frequently in LQT2 (LQT1: 25% vs 3%; control 9%, P = .02). Low-dose epinephrine-induced G2-T waves were detected exclusively in LQT2 (18%). Low-dose epinephrine elicited G1/G2-T waves in 8 of 15 LQT2 patients with a nondiagnostic baseline QTc. CONCLUSIONS: Biphasic and G1-T waves are nonspecific responses to high-dose epinephrine. Changes in T-wave morphology during low-dose epinephrine (<0.05 microg/kg/min) may yield diagnostic information. G2-notched T waves elicited during low-dose epinephrine may unmask some patients with concealed LQT2.

Syncope in children and adolescents and the congenital long QT syndrome.

From a population-based epidemiologic cohort of children and adolescents who sought medical attention for syncope (n = 151), screening 12-lead electrocardiograms were obtained from 118 patients (79 female) to determine the frequency of significant QT prolongation. The distribution of heart rate corrected QT intervals (QTc) was compared with age- and sex-matched controls. Only one patient had QTc >470 ms.

Epinephrine-induced QT interval prolongation: a gene-specific paradoxical response in congenital long QT syndrome.

OBJECTIVE: To determine the effect of epinephrine on the QT interval in patients with genotyped long QT syndrome (LQTS). PATIENTS AND METHODS: Between May 1999 and April 2001, 37 patients (24 females) with genotyped LQTS (19 LQT1, 15 LQT2, 3 LQT3, mean age, 27 years; range, 10-53 years) from 21 different kindreds and 27 (16 females) controls (mean age, 31 years; range, 13-45 years) were studied at baseline and during gradually increasing doses of intravenous epinephrine infusion (0.05, 0.1, 0.2, and 0.3 microg x k(-1) x min(-1)). The 12-lead electrocardiogram was monitored continuously, and heart rate, QT, and corrected QT interval (QTc) were measured during each study stage. RESULTS: There was no significant difference in resting heart rate or chronotropic response to epinephrine between LQTS patients and controls. The mean +/- SD baseline QTc was greater in LQTS patients (500+/-68 ms) than in controls (436+/-19 ms, P<.001). However, 9 (47%) of 19 KVLQT1-genotyped LQT1 patients had a nondiagnostic resting QTc (<460 milliseconds), whereas 11 (41%) of 27 controls had a resting QTc higher than 440 milliseconds. During epinephrine infusion, every LQT1 patient manifested prolongation of the QT interval (paradoxical response), whereas healthy controls and patients with either LQT2 or LQT3 tended to have shortened QT intervals (P<.001). The maximum mean +/- SD change in QT (AQT [epinephrine QT minus baseline QT]) was -5+/-47 ms (controls), +94+/-31 ms (LQT1), and -87+/-67 ms (LQT2 and LQT3 patients). Of 27 controls, 6 had lengthening of their QT intervals (AQT >30 milliseconds) during high-dose epinephrine. Low-dose epinephrine (0.05 microg x kg(-1) x min(-1)) completely discriminated LQT1 patients (AQT, +82+/-34 ms) from controls (AQT, -7+/-13 ms; P<.001). Epinephrine-triggered nonsustained ventricular tachycardia occurred in 2 patients with LQTS and in 1 control. CONCLUSIONS: Epinephrine-induced prolongation of the QT interval appears pathognomonic for LQT1. Low-dose epinephrine infusion distinguishes controls from patients with concealed LQT1 manifesting an equivocal QTc at rest. Thus, epinephrine provocation may help unmask some patients with concealed LQTS and strategically direct molecular genetic testing.