Guidelines for Performing a Comprehensive Pediatric Transthoracic Echocardiogram: Recommendations From the American Society of Echocardiography.

Echocardiography is a fundamental component of pediatric cardiology, and appropriate indications have been established for its use in the setting of suspected, congenital, or acquired heart disease in children. Since the publication of guidelines for pediatric transthoracic echocardiography in 2006 and 2010, advances in knowledge and technology have expanded the scope of practice beyond the use of traditional modalities such as two-dimensional, M-mode, and Doppler echocardiography to evaluate the cardiac segmental structures and their function. Adjunct modalities such as contrast, three-dimensional, and speckle-tracking echocardiography are now used routinely at many pediatric centers. Guidelines and recommendations for the use of traditional and newer adjunct modalities in children are described in detail in this document. In addition, suggested protocols related to standard operations, infection control, sedation, and quality assurance and improvement are included to provide an organizational structure for centers performing pediatric transthoracic echocardiograms.

Common pulmonary vein atresia.

A 4-hour-old infant with profound cyanosis on an alprostadil infusion was urgently transferred to Rady Children's Hospital with suspected CHD. Upon arrival, urgent echocardiography was performed but could not confirm the presence of discrete pulmonary veins or pulmonary venous drainage. Given the difficulty in delineating the anatomy, a cardiac CT scan was performed and demonstrated a nearly atretic common pulmonary vein with multiple small collaterals that drained to systemic veins. Due to the high risk of mortality associated with operative repair, the decision was made to proceed with compassionate withdrawal of care. The described anatomy of common pulmonary vein atresia remains rare, and to our knowledge, fewer than 40 cases have been reported in the literature. Albeit rare, common pulmonary vein atresia should be considered in the differential diagnosis of a severely cyanotic neonate.

Anakinra Treatment in Patients with Acute Kawasaki Disease with Coronary Artery Aneurysms: A Phase I/IIa Trial.

OBJECTIVES: To determine the safety, pharmacokinetics, and immunomodulatory effects of 2-6 weeks of anakinra therapy in patients with acute Kawasaki disease with a coronary artery aneurysm (CAA). STUDY DESIGN: We performed a Phase I/IIa dose-escalation study of anakinra (2-11 mg/kg/day) in 22 patients with acute Kawasaki disease with CAA. We measured interleukin (IL)-1RA concentrations after the first dose and trough levels up to study week 6. Markers of inflammation and coronary artery z-scores were assessed pretreatment and at 48 hours, 2 weeks, and 6 weeks after initiation of therapy. RESULTS: Up to 6 weeks of anakinra (up to 11 mg/kg/day) was safe and well tolerated by the 22 participants (median age, 1.1 years), with no serious adverse events attributable to the study drug. All participants were treated with intravenous immunoglobulin (IVIG), and 20 also received infliximab (10 mg/kg) before initiation of anakinra. Serum levels of IL-6, IL-8, and tumor necrosis factor α decreased similarly in patients with Kawasaki disease treated with IVIG, infliximab, and anakinra compared with age- and sex-matched patients with Kawasaki disease treated only with IVIG and infliximab. Anakinra clearance increased with illness day at diagnosis. Simulations demonstrated that more frequent intravenous (IV) dosing may result in more sustained concentrations without significantly increasing the peak concentration compared with subcutaneous (SC) dosing. CONCLUSIONS: Both IV and SC anakinra are safe in infants and children with acute Kawasaki disease and CAA. IV dosing every 8-12 hours during the acute hospitalization of patients with Kawasaki disease may result in a sustained concentration while avoiding frequent SC injections. The efficacy of a short course of IV therapy during hospitalization should be studied. TRIAL REGISTRATION CLINICALTRIALS.GOV: NCT02179853.

Infliximab versus second intravenous immunoglobulin for treatment of resistant Kawasaki disease in the USA (KIDCARE): a randomised, multicentre comparative effectiveness trial.

BACKGROUND: Although intravenous immunoglobulin (IVIG) is effective therapy for Kawasaki disease, 10-20% of patients have recrudescent fever as a sign of persistent inflammation and require additional treatment. We aimed to compare infliximab with a second infusion of IVIG for treatment of resistant Kawasaki disease. METHODS: In this multicentre comparative effectiveness trial, patients (aged 4 weeks to 17 years) with IVIG resistant Kawasaki disease and fever at least 36 h after completion of their first IVIG infusion were recruited from 30 hospitals across the USA. Patients were randomly assigned (1:1) to second IVIG (2 g/kg over 8-12 h) or intravenous infliximab (10 mg/kg over 2 h without premedication), by using a randomly permuted block randomisation design with block size of two or four. Patients with fever 24 h to 7 days following completion of first study treatment crossed over to receive the other study treatment. The primary outcome measure was resolution of fever at 24 h after initiation of study treatment with no recurrence of fever attributed to Kawasaki disease within 7 days post-discharge. Secondary outcome measures included duration of fever from enrolment, duration of hospitalisation after randomisation, and changes in markers of inflammation and coronary artery Z score. Efficacy was analysed in participants who received treatment and had available outcome values. Safety was analysed in all randomised patients who did not withdraw consent. This clinical trial is registered with ClinicalTrials.gov, NCT03065244. FINDINGS: Between March 1, 2017, and Aug 31, 2020, 105 patients were randomly assigned to treatment and 103 were included in the intention-to-treat population (54 in the infliximab group, 49 in the second IVIG group). Two patients randomised to infliximab did not receive allocated treatment. The primary outcome was met by 40 (77%) of 52 patients in the infliximab group and 25 (51%) of 49 patients in the second IVIG infusion group (odds ratio 0·31, 95% CI 0·13-0·73, p=0·0076). 31 patients with fever beyond 24 h received crossover treatment: nine (17%) in the infliximab group received second IVIG and 22 (45%) in second IVIG group received infliximab (p=0·0024). Three patients randomly assigned to infliximab and two to second IVIG with fever beyond 24h did not receive crossover treatment. Mean fever days from enrolment was 1·5 (SD 1·4) for the infliximab group and 2·5 (2·5) for the second IVIG group (p=0·014). Mean hospital stay was 3·2 days (2·1) for the infliximab group and 4·5 days (2·5) for the second IVIG group (p<0·001). There was no difference between treatment groups for markers of inflammation or coronary artery outcome. 24 (44%) of 54 patients in the infliximab group and 33 (67%) of 49 in the second IVIG group had at least one adverse event. A drop in haemoglobin concentration of at least 2g/dL was seen in 19 (33%) of 58 patients who received IVIG as either their first or second study treatment (three of whom required transfusion) and in three (7%) of 43 who received only infliximab (none required transfusion; p=0·0028). Haemolytic anaemia was the only serious adverse events deemed definitely or probably related to study treatment, and was reported in nine (15%) of 58 patients who received IVIG as either their first or second study treatment and none who received infliximab only. INTERPRETATION: Infliximab is a safe, well tolerated, and effective treatment for patients with IVIG resistant Kawasaki disease, and results in shorter duration of fever, reduced need for additional therapy, less severe anaemia, and shorter hospitalisation compared with second IVIG infusion. FUNDING: Patient Centered Outcomes Research Institute.

Abnormal pulmonary perfusion heterogeneity in patients with Fontan circulation and pulmonary arterial hypertension.

KEY POINTS: The distribution of pulmonary perfusion is affected by gravity, vascular branching structure and active regulatory mechanisms, which may be disrupted by cardiopulmonary disease, but this is not well studied, particularly in rare conditions. We evaluated pulmonary perfusion in patients who had undergone Fontan procedure, patients with pulmonary arterial hypertension (PAH) and two groups of controls using a proton magnetic resonance imaging technique, arterial spin labelling to measure perfusion. Heterogeneity was assessed by the relative dispersion (SD/mean) and gravitational gradients. Gravitational gradients were similar between all groups, but heterogeneity was significantly increased in both patient groups compared to controls and persisted after removing contributions from large blood vessels and gravitational gradients. Patients with Fontan physiology and patients with PAH have increased pulmonary perfusion heterogeneity that is not explainable by differences in mean perfusion, gravitational gradients, or large vessel anatomy. This probably reflects vascular remodelling in PAH and possibly in Fontan physiology. ABSTRACT: Many factors affect the distribution of pulmonary perfusion, which may be disrupted by cardiopulmonary disease, but this is not well studied, particularly in rare conditions. An example is following the Fontan procedure, where pulmonary perfusion is passive, and heterogeneity may be increased because of the underlying pathophysiology leading to Fontan palliation, remodelling, or increased gravitational gradients from low flow. Another is pulmonary arterial hypertension (PAH), where gravitational gradients may be reduced secondary to high pressures, but remodelling may increase perfusion heterogeneity. We evaluated regional pulmonary perfusion in Fontan patients (n = 5), healthy young controls (Fontan control, n = 5), patients with PAH (n = 6) and healthy older controls (PAH control) using proton magnetic resonance imaging. Regional perfusion was measured using arterial spin labelling. Heterogeneity was assessed by the relative dispersion (SD/mean) and gravitational gradients. Mean perfusion was similar (Fontan = 2.50 ± 1.02 ml min-1  ml-1 ; Fontan control = 3.09 ± 0.58, PAH = 3.63 ± 1.95; PAH control = 3.98 ± 0.91, P = 0.26), and the slopes of gravitational gradients were not different (Fontan = -0.23 ± 0.09 ml min-1  ml-1  cm-1 ; Fontan control = -0.29 ± 0.23, PAH = -0.27 ± 0.09, PAH control = -0.25 ± 0.18, P = 0.91) between groups. Perfusion relative dispersion was greater in both Fontan and PAH than controls (Fontan = 1.46 ± 0.18; Fontan control = 0.99 ± 0.21, P = 0.005; PAH = 1.22 ± 0.27, PAH control = 0.91 ± 0.12, P = 0.02) but similar between patient groups (P = 0.13). These findings persisted after removing contributions from large blood vessels and gravitational gradients (all P < 0.05). We conclude that patients with Fontan physiology and PAH have increased pulmonary perfusion heterogeneity that is not explained by differences in mean perfusion, gravitational gradients, or large vessel anatomy. This probably reflects the effects of remodelling in PAH and possibly in Fontan physiology.

Exercise MRI highlights heterogeneity in cardiovascular mechanics among patients with Fontan circulation: proposed protocol for routine evaluation.

Single ventricle physiology and palliation via the Fontan operation lead to a series of cardiovascular changes. In addition, organs such as the kidneys and liver have been shown to experience insults and subsequent injury. This has led to routine surveillance of patients. We present findings from a small cohort of patients that was deeply phenotyped to illustrate the need for comprehensive evaluation. A cohort of four Fontan patients with fairly high cardiovascular function was recruited 5-10 years post-Fontan. Patients underwent a rigorous clinical work-up after which a research MRI scan was performed during which (I) data were obtained during exercise to evaluate changes in stroke volume during supine exercise and (II) magnetic resonance angiograms with phase-contrast images were obtained for computational modeling of flows through the Fontan circulation at rest. Clinical measures were consistent with a fairly homogeneous high function cohort (peak oxygen consumption >20 mL/kg/min, robust response to exercise, peak ventilatory efficiency below levels associated with heart failure, MR-derived ejection fraction >50%). Liver evaluation did not reveal clear signs of cirrhosis or extensive fibrosis. However, we observed considerable variability (27-162%) in the increase in stroke index with exercise [100%±64% increase, 53.9±17.4 mL/beat m2 (rest), 101.1±20.7 mL/beat m2, (exercise)]. Computational flow modeling at rest in two patients also showed marked differences in flow distribution and shear stress. We report marked differences in both changes in stroke index during an exercise MRI protocol as well as computational flow patterns at rest suggesting different compensation strategies may be associated with high functioning Fontan patients. The observed heterogeneity illustrates the need for deep phenotyping to capture patient-specific adaptive mechanisms.

Phase I/IIa Trial of Atorvastatin in Patients with Acute Kawasaki Disease with Coronary Artery Aneurysm.

OBJECTIVES: To determine the safety, tolerability, pharmacokinetics, and immunomodulatory effects of a 6-week course of atorvastatin in patients with acute Kawasaki disease with coronary artery (CA) aneurysm (CAA). STUDY DESIGN: This was a Phase I/IIa 2-center dose-escalation study of atorvastatin (0.125-0.75 mg/kg/day) in 34 patients with Kawasaki disease (aged 2-17 years) with echocardiographic evidence of CAA. We measured levels of the brain metabolite 24(S)-hydroxycholesterol (24-OHC), serum lipids, acute-phase reactants, liver enzymes, and creatine phosphokinase; peripheral blood mononuclear cell populations; and CA internal diameter normalized for body surface area before atorvastatin treatment and at 2 and 6 weeks after initiation of atorvastatin treatment. RESULTS: A 6-week course of up to 0.75 mg/kg/day of atorvastatin was well tolerated by the 34 subjects (median age, 5.3 years; IQR, 2.6-6.4 years), with no serious adverse events attributable to the study drug. The areas under the curve for atorvastatin and its metabolite were larger in the study subjects compared with those reported in adults, suggesting a slower rate of metabolism in children. The 24-OHC levels were similar between the atorvastatin-treated subjects and matched controls. CONCLUSIONS: Atorvastatin was safe and well tolerated in our cohort of children with acute Kawasaki disease and CAA. A Phase III efficacy trial is warranted in this patient population, which may benefit from the known anti-inflammatory and immunomodulatory effects of this drug.

Partial Jacobsen syndrome phenotype in a patient with a de novo frameshift mutation in the ETS1 transcription factor.

Jacobsen syndrome (OMIM #147791) is a rare contiguous gene disorder caused by deletions in distal 11q. The clinical phenotype is variable and can include dysmorphic features, varying degrees of intellectual disability, behavioral problems including autism and attention deficit hyperactivity disorder, congenital heart defects, structural kidney defects, genitourinary problems, immunodeficiency, and a bleeding disorder due to impaired platelet production and function. Previous studies combining both human and animal systems have implicated several disease-causing genes in distal 11q that contribute to the Jacobsen syndrome phenotype. One gene, ETS1, has been implicated in causing congenital heart defects, structural kidney defects, and immunodeficiency. We performed a comprehensive phenotypic analysis on a patient with congenital heart disease previously found to have a de novo frameshift mutation in ETS1, resulting in the loss of the DNA-binding domain of the protein. Our results suggest that loss of Ets1 causes a "partial Jacobsen syndrome phenotype" including congenital heart disease, facial dysmorphism, intellectual disability, and attention deficit hyperactivity disorder.

Determinants of Physician, Sonographer, and Laboratory Productivity: Analysis of the Third Survey from the American Society of Echocardiography Committee on Pediatric Echocardiography Laboratory Productivity.

BACKGROUND: The American Society of Echocardiography Committee on Pediatric Echocardiography Laboratory Productivity was formed in 2011 to study institutional factors that could influence the clinical productivity of physicians and sonographers in academic pediatric echocardiography laboratories. In the previous two surveys, staff clinical productivity remained stable while total echocardiography volumes increased. This third survey was designed to assess how clinical productivity is associated with laboratory infrastructure elements such as training, administrative tasks, quality improvement, research, and use of focused cardiac ultrasound (FCU). METHODS: Survey questions were sent by e-mail to North American laboratories. The aims were to assess (1) educational and training obligations, (2) academic productivity and research, (3) laboratory medical director satisfaction, (4) quality improvement, (5) laboratory leadership roles, and (6) impact and use of FCU. Survey responses were compared with clinical productivity metrics defined in the first two surveys. RESULTS: There were 38 responses. Academic productivity was higher at institutions with more dedicated imaging personnel, personnel with dedicated protected academic time, and advanced imaging fellows. Academic productivity did not correlate with clinical productivity and was not significantly affected by the presence of dedicated research sonographers. The satisfaction level of laboratory medical directors was related to dedicated administrative time and an administrative stipend. The majority of administrative roles were tasked to the laboratory medical director with support of the technical director. FCU was listed as a hospital privilege at four institutions (13%). Twenty-two (58%) were training FCU providers in one or more subspecialties. FCU was not associated with clinical or academic productivity. CONCLUSIONS: This third survey gathered supplemental data to complement the clinical productivity data collected from the first two surveys. Together, the results of these surveys further describe the range of factors that can affect North American academic pediatric echocardiography laboratories.

Influence of Aortic Stiffness on Aortic-Root Growth Rate and Outcome in Patients With the Marfan Syndrome.

The Pediatric Heart Network randomized trial of atenolol versus losartan in the Marfan syndrome showed no treatment differences in the rates of aortic-root growth or clinical outcomes. In this report we present treatment effects on aortic stiffness and determine whether baseline aortic stiffness predicts aortic-root growth and clinical outcomes. Echocardiograms at 0, 6, 12, 24, and 36 months from 608 subjects (6 months to 25 years) who met original Ghent criteria and had a maximum aortic-root z-score (ARz) >3 were centrally reviewed. Stiffness index (SI) and elastic modulus (EM) were calculated for aortic root and ascending aorta. Data were analyzed using multivariable mixed effects modeling and Cox regression. Heart rate-corrected aortic-root SI over 3 years decreased with atenolol but did not change with losartan (-0.298 ± 0.139 vs 0.141 ± 0.139/year, p = 0.01). In the entire cohort, above-median aortic-root SI (>9.1) and EM (>618 mm Hg) predicted a smaller annual decrease in ARz (p ≤0.001). Upper-quartile aortic-root EM (>914 mm Hg) predicted the composite outcome of aortic-root surgery, dissection, or death (hazard ratio 2.17, 95% confidence interval 1.02 to 4.63, p = 0.04). Crude 3-year event rates were 10.4% versus 3.2% for higher versus lower EM groups. In conclusion, atenolol was associated with a decrease in aortic-root SI, whereas losartan was not. Higher baseline aortic-root SI and EM were associated with a smaller decrease in ARz and increased risk for clinical outcomes. These data suggest that noninvasive aortic stiffness measures may identify patients at higher risk of progressive aortic enlargement and adverse clinical outcomes, potentially allowing for closer monitoring and more aggressive therapy.

Utility of Echocardiography as Screening for Late-onset Anthracycline-induced Cardiotoxicity in Pediatric Cancer Survivors: Observations from the First Decade After End of Therapy.

Current screening guidelines are available for anthracycline-induced cardiotoxicity. However, the utility of echocardiogram screening for late-onset anthracycline cardiotoxicity especially in the decade immediately after end of therapy is debatable. A retrospective chart review of patients seen in the Thriving after Cancer Clinic at Rady Children's Hospital January 2006 to December 2013 was performed. Treatment data, echocardiogram results, cardiology referral notes and cardiac medication data were abstracted from anthracycline-exposed survivors. Descriptive and univariate comparative statistics were performed. Of 368 patients (45% female, median 5.3 y old at diagnosis [range 0 to 18.3], median 5.0 y from end of therapy [EOT] [range 0 to 18.2]), a total of 4 patients (10-year cumulative incidence after EOT 1.3%; 95% confidence interval, 0.1%-19.7%) required cardiac medication for late-onset cardiotoxicity (>1 y after EOT). Those requiring medication for late-onset cardiotoxicity were exposed to more anthracyclines than survivors without cardiotoxicity (median, 360 mg/m [range, 300 to 375 mg/m] vs. 182 mg/m [range, 26 to 515 mg/m], P=0.009). None had neck or chest radiation. In this population, medication initiation for late-onset anthracycline cardiotoxicity was limited predominantly to the first 3 years after EOT, with the next >13 years after EOT. These findings add to the growing body of literature assessing current guidelines to inform improvements in screening practices of survivorship providers.

Double trouble: fetal diagnosis of a pulmonary artery sling and vascular ring.

Left pulmonary artery slings and vascular rings are rare congenital anomalies definable by fetal echocardiography. Left pulmonary artery slings are associated with high respiratory morbidity and mortality. Prenatal diagnosis of a left pulmonary artery sling should prompt delivery planning for postnatal management at a pediatric tertiary care center.

Evaluation of Impedance Cardiography for Measurement of Stroke Volume in Congenital Heart Disease.

Noninvasive measurement of cardiac output (CO) and particularly stroke volume (SV) remain difficult but potentially valuable. These variables can be particularly challenging to measure in children with congenital heart disease (CHD). Impedance cardiography (IC) is a technique shown to be accurate in measuring SV in adults and in children with structurally normal hearts. The ease of use and rapidity of SV measurement using IC makes it potentially attractive for young patients with CHD. Advances in IC technology have led to more sophisticated signal-morphology IC (SMIC) devices that may further improve accuracy. We tested the accuracy of SMIC to measure SV in 21 subjects with CHD by comparing measurements with those from cardiac magnetic resonance (CMR) imaging. There was good agreement between SMIC and CMR in measurement of SV: mean difference = 1.7 ml (p = 0.47); r = 0.89. The agreement and correlation persisted when controlling for the differences in blood pressure and heart rate during the two testing methods. We conclude that SMIC is accurate at measuring SV and thus CO when compared to CMR in a variety of forms of CHD.

Preprocedural Transthoracic Echocardiography Can Predict Amplatzer Septal Occluder Device Size for Transcatheter Atrial Septal Defect Closure.

OBJECTIVE: To evaluate whether preprocedural transthoracic echocardiography (TTE) can be used to predict Amplatzer septal occluder (ASO) size for device closure of atrial septal defect (ASD). DESIGN: Retrospective review of patients who underwent ASD device closure at our institution between August 2006 and August 2013 was performed. Patients with complex congenital heart disease, devices other than the ASO, multiple devices, or inadequate TTE images were excluded. Those who had transesophageal echocardiography (TEE)-guided device placement were evaluated. A blinded observer reviewed their preprocedural TTE images and applied a scaled formula to predict device size. RESULTS: A total of 186 patients underwent ASO placement during the study period, 87 had TEE guidance, of which 45 met inclusion criteria. The mean predicted device size by the scaled formula was 18.0 ± 5.11 mm, compared to the mean implanted device size of 18.8 ± 5.22 mm. The mean absolute difference between each predicted and final deployed device size was 1.44 mm with 95% CI [1.08, 1.81]. The Pearson correlation showed that the predicted device size had a positive correlation coefficient of 0.94. CONCLUSION: Preprocedural TTE assessment of ASD size using a scaling formula in patients with adequate TTE windows can accurately predict ASO device size and aid in device selection.

Left Ventricular Mechanical Property Changes During Acute AV Synchronous Right Ventricular Pacing in Children.

Prolonged RV pacing is recognized as a cause of LV dysfunction due to dyssynchronous activation. There are no specific longitudinal parameters known to help predict RV pacing-induced LV dysfunction. The aim of the study was to assess the acute effects of AV synchronous RV pacing on LV mechanics using echocardiographic speckle tracking. Nineteen children, aged 6-23 years, underwent echocardiographic evaluation prior to and following elective electrophysiology and ablation studies. The subjects were evaluated in sinus rhythm and later with AV synchronous RV pacing at a cycle length of 550 ms with a short AV delay of 80 ms. The echocardiographic clips were analyzed using speckle tracking methods to calculate LV circumferential and longitudinal strain, rotation and twist in all conditions. Acute RV apical pacing decreased LV longitudinal strain from 16.1 ± 3.7% in sinus rhythm to 14.4 ± 3.3% (p = 0.03) and LV base rotation from -8.4° ± 3.6° to -6.4° ± 4.0° (p = 0.04). The circumferential strain, apical rotation and LV twist were not affected. Separate analysis of subjects with no prior preexcitation showed that acute RV pacing caused significant twist reduction, from 15.9° ± 7.6° to 12.1° ± 7.0° (p = 0.02), and decreased longitudinal strain and base rotation. Patients with preexcitation had abnormalities that persisted acutely after ablation. Acute RV apical pacing causes reductions in LV base rotation, longitudinal strain and twist. The recognition of abnormal LV activation patterns may provide longitudinal clues to LV dysfunction in chronically paced patients and potential novel indices of effective CRT interventions to reverse these abnormalities.

Pulmonary Artery Dilation and Right Ventricular Function in Acute Kawasaki Disease.

Coronary artery inflammation and aneurysm formation are the most common complications of Kawasaki disease (KD). Valvulitis and myocarditis are also well described and may lead to valvar regurgitation and left ventricular dysfunction. However, functional changes in the right heart have rarely been reported. We noted several acute KD patients with dilated pulmonary arteries (PA) and thus sought to systematically characterize PA size and right-heart function in an unselected cohort of KD patients cared for at a single clinical center. Clinical, laboratory, and echocardiographic data from 143 acute KD subjects were analyzed. PA dilation was documented in 23 subjects (16.1 %); these subjects had higher median right ventricle myocardial performance index (RV MPI), higher ratio of early tricuspid inflow velocity to tricuspid annular early diastolic velocity (TV E/e'), and lower median TV e' velocity compared to the non-PA dilation group (0.50 vs 0.38 p < 0.01, 4.2 vs 3.6 p < 0.05, and 13.5 vs 15.2 cm/s p < 0.01, respectively). Almost all subjects with PA dilation had improved PA Z-score, RV MPI, and TV E/e' in the subacute phase (p < 0.01). There were no significant differences in indices of left ventricle function between PA dilation group and non-PA dilation group. In summary, PA dilation was documented in 16 % of acute KD subjects. These subjects were more likely to have echocardiographic indices consistent with isolated RV dysfunction that improved in the subacute phase. The long-term consequence of these findings will require longitudinal studies of this patient population.