Regression equations for calculation of z scores of cardiac structures in a large cohort of healthy infants, children, and adolescents: an echocardiographic study

Pathophysiology, screening and diagnosis of pulmonary hypertension in infants with bronchopulmonary dysplasia - A review of the literature

Bronchopulmonary dysplasia (BPD) is a common complication of extreme prematurity, which has increased over the last 20 years. BPD is associated with increased morbidities and mortality. It has been increasingly recognized that BPD affects overall lung development including the pulmonary vasculature. More recent studies have demonstrated an increased awareness of pulmonary arterial hypertension (PH) in BPD patients and recent international guidelines have advocated for better screening. This review will describe the current understanding of the pathophysiology of PH in infants with BPD, the in-depth assessment of the available literature linking PH and BPD, and propose an approach of screening and diagnosis of PH in infants with BPD.

Optimal Z-Score Use in Surgical Decision-Making in Pulmonary Atresia With Intact Ventricular Septum

Objectives:

In the surgical treatment of pulmonary atresia with intact ventricular septum, the size of the tricuspid valve annulus (as measured by z-scores) has emerged as a significant factor in deciding which repair to perform. Various tricuspid valve annulus z-scores are reported as “cutoffs” for successful biventricular repair. We aimed to determine whether the use of different z-score data sets contributed to the gross variation in “cutoffs” for successful biventricular repair reported in the literature.

Methods:

A single search was made of PubMed using the “advanced” setting with the following search terms: pulmonary, atresia, intact, septum, z, and score. The filters “title” and “title/abstract” were used for the first four and last two terms, respectively; the instruction “AND” combined all terms. Articles that identified which z-score data set was used in patients with biventricular repairs were included.

Results:

From 13 articles, 1,392 patients were studied, 410 (29.5%) of which achieved biventricular repair. Three z-score data sets were quoted; mean tricuspid valve annulus z-scores in biventricular repair patients ranged between −0.53 and −5.1. After correcting for discrepancies between z-score data sets, no study reported a mean tricuspid valve annulus z-score <−2.8 in biventricular repair patients and 83.3% reported mean tricuspid valve annuli z-scores >−1.7.

Conclusion:

The use of varied tricuspid valve annuli z-score data sets may have contributed to gross variations in reported “cutoffs” for successful biventricular repair. This could lead to inappropriate surgical pathway allocation.

Outcomes After Decompression of the Right Ventricle in Infants With Pulmonary Atresia With Intact Ventricular Septum Are Associated With Degree of Tricuspid Regurgitation

Background—

Outcomes after right ventricle (RV) decompression in infants with pulmonary atresia with intact ventricular septum vary widely. Descriptions of outcomes are limited to small single-center studies.

Methods and Results—

Neonates undergoing RV decompression for pulmonary atresia with intact ventricular septum were included from 4 pediatric centers. Primary end point was reintervention post-RV decompression; secondary end points included circulation type at latest follow-up. Ninety-nine patients (71 with pulmonary atresia with intact ventricular septum and 28 with virtual atresia) underwent RV decompression at median 3 (25th–75th, 2–5) days of age. Seventy-one patients (72%) underwent at least 1 reintervention after decompression. Median duration of follow-up was 3 years (range, 1–10). Freedom from reintervention was 51% at 1 month and 23% at 3 years. In multivariable analysis, reintervention was associated with virtual atresia (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.28–091; P =0.027), smaller RV length (HR, 0.94; 95% CI, 0.89–0.99; P =0.027), and ≤mild tricuspid regurgitation (TR; HR, 3.58; 95% CI, 2.04–6.30; P <0.001). Patients undergoing surgical shunt or ductal stent were less likely to have virtual atresia (HR, 0.36; 95% CI, 0.15–0.85; P =0.02) and more likely to have higher RV end-diastolic pressure (HR, 1.07; 95% CI, 1.00–1.15; P =0.057) and ≤mild TR (HR, 3.50; 95% CI, 1.75–7.0; P <0.001). Number of reinterventions was associated with ≤mild TR (rate ratio, 1.87; 95% CI, 1.23–2.87; P =0.0037). Multivariable analysis indicated that <2-ventricle circulation status was associated with ≤mild TR (odds ratio, 18.6; 95% CI, 5.3–65.2; P <0.001) and lower RV area (odds ratio, 0.81; 95% CI, 0.72–0.91; P <0.001).

Conclusions—

Patients with pulmonary atresia with intact ventricular septum deemed suitable for RV decompression have a high reintervention burden although most achieve 2-ventricle circulation. TR ≤mild at baseline is strongly associated with reintervention and <2-ventricle circulation at medium-term follow-up. Degree of baseline TR may be an important marker of long-term outcomes in this population.

Preprocedural Risk Assessment Prior to PPVI with CMR and Cardiac CT

Percutaneous pulmonary valve intervention (PPVI) is a less invasive and less costly approach to pulmonary valve replacement compared with the surgical alternative. Potential complications of PPVI include coronary compression and pulmonary arterial injury/rupture. The purpose of this study was to characterize the morphological risk factors for PPVI complication with cardiac MRI and cardiac CTA. A retrospective review of 88 PPVI procedures was performed. 44 patients had preprocedural cardiac MRIs or CTAs available for review. Multiple morphological variables on cardiac MRI and CTA were compared with known PPVI outcome and used to investigate associations of variables in determining coronary compression or right ventricular-pulmonary arterial conduit injury. The most significant risk factor for coronary artery compression was the proximity of the coronary arteries to the conduit. In all patients with coronary compression during PPVI, the coronary artery touched the conduit on the preprocedural CTA/MRI, whilst in patients without coronary compression the mean distance between the coronary artery and the conduit was 4.9 mm (range of 0.8-20 mm). Multivariable regression analysis demonstrated that exuberant conduit calcification was the most important variable for determining conduit injury. Position of the coronary artery directly contacting the conduit without any intervening fat may predict coronary artery compression during PPVI. Exuberant conduit calcification increases the risk of PPVI-associated conduit injury. Close attention to these factors is recommended prior to intervention in patients with pulmonary valve dysfunction.

Exome sequencing identifies primary carnitine deficiency in a family with cardiomyopathy and sudden death

Pediatric cardiomyopathy is a rare but severe disease with high morbidity and mortality. The causes are poorly understood and can only be established in one-third of cases. Recent advances in genetic technologies, specifically next-generation sequencing, now allow for the detection of genetic causes of cardiomyopathy in a systematic and unbiased manner. This is particularly important given the large clinical variability among pediatric cardiomyopathy patients and the large number of genes (>100) implicated in the disorder. We report on the performance of whole-exome sequencing in members of a consanguineous family with a history of pediatric hypertrophic cardiomyopathy and sudden cardiac death, which led to the identification of a homozygous stop variant in the SLC22A5 gene, implicated in primary carnitine deficiency, as the likely genetic cause. Targeted carnitine tandem mass spectrometry analysis in the patient revealed complete absence of plasma-free carnitine and only trace levels of total carnitine, further supporting the causality of the SLC22A5 variant. l-carnitine supplementation in the proband led to a rapid and marked clinical improvement. This case illustrates the use of exome sequencing as a systematic and unbiased diagnostic tool in pediatric cardiomyopathy, providing an efficient route to the identification of the underlying cause, which lead to appropriate treatment and prevention of premature death.

Measurement of Aortic Valve Coaptation and Effective Height Using Echocardiography in Patients with Ventricular Septal Defects and Aortic Valve Prolapse

Decreased coaptation height in adults has been identified as a marker of early valve failure. We evaluated aortic valve coaptation and effective height in healthy children and in children with a ventricular septal defect (VSD) with aortic cusp prolapse (ACP), using echocardiography. We included 45 subjects with VSD with ACP, 27 did not develop aortic regurgitation (AR) by ACP and 18 developed AR by ACP, and 83 healthy children as controls. Aortic root anatomy was estimated using the parasternal long-axis view. We measured the diameter of aortic valve (AV), coaptation height (CH), and effective height (EH) of the aortic valve. We defined the ACH (CH/AV ratio) and AEH (EH/AV ratio) indices as follows: [Formula: see text]. There were significant differences in ACH and AEH between the groups (control vs VSD with ACP vs VSD with ACP and AR, median ACH [%], 35.1 vs 32.0 vs 22.1; median AEH [%], 52.0 vs 48.0 vs 34.4, respectively; P < 0.01]). Intra-cardiac repair (ICR) was performed in 15 cases. Significant increases were observed in ACH and AEH before and after ICR (median ACH [%], before: 27.0, after: 32.7, P < 0.05; median AEH (%), before 38.5, after 45.8, P < 0.05). Measurement of ACH and AEH may allow direct and non-invasive assessment of the severity of VSD with ACP, which could aid clinicians in determining the need and timing for surgical intervention.

Normative Values of Aortic Arch Structures in Premature Infants

BACKGROUND

Aortic arch abnormalities represent 5% to 8% of all congenital heart disease. Measurements of the aortic arch dimensions on two-dimensional echocardiographic images remain of critical importance in the diagnosis of aortic arch pathology. To define aortic hypoplasia or coarctation, measured dimensions must be compared with normal values. Normal values have been described for children of all ages in earlier studies. However, normative data for premature infants are not yet available. Therefore, the aim of this study was to develop normative data in a cohort of premature infants, which could be used in the diagnosis of aortic arch abnormalities.

METHODS

A single-center study was conducted in a large population of premature infants with gestational ages of ≤32 weeks without hemodynamically important congenital heart disease, chromosomal abnormalities, and/or major cerebral congenital malformations. Two-dimensional echocardiographic measurements of four aortic arch structures were made on the second, fourth, and sixth days after birth.

RESULTS

Three hundred eighty-five preterm patients were included. No differences in dimensions were found among days 2, 4, and 6. The dimension of the isthmus showed no significant relation to the existence of a patent ductus arteriosus. Reference intervals with mean and SD were calculated across the range of birth weight. Regression analysis was performed with multiple determinants in different models. The best predictive value was found for birth weight in a cubic model.

CONCLUSIONS

This work provides regression equations for the calculation of Z scores and reference intervals for aortic arch dimensions in a cohort of preterm infants born at gestational ages of ≤32 weeks. The normative data can be used in diagnosis and decision making involving aortic arch pathology in premature infants.

A pediatric echocardiographic Z-score nomogram for a developing country: Indian pediatric echocardiography study - The Z-score

Background:

Almost all presently available pediatric echocardiography Z-score nomograms are based on Western data. They may not be a suitable reference standard for assessing the sizes of cardiac structures of children from developing countries.

Objective:

This study's objective was to collect normative data of 21 commonly measured cardiovascular structures using M-mode and two-dimensional echocardiography in Indian children aged between 4 and 15 years and to derive Z-score nomograms for each.

Subjects and Methods:

The study was conducted at two centers in India - Ajmer, Rajasthan, and Mohali, Punjab. We studied a community-based sample involving healthy school going children. After excluding children with cardiovascular abnormalities on the screening echocardiogram, 746 children were included in the final analysis. Echocardiographic assessment was performed using a Philips iE33 system.

Results and Analysis:

For each parameter measured, seven models were evaluated to assess the relationship of that parameter with the body surface area and the one with the best fit was used to plot the Z-score chart for that parameter. Z score charts were thus derived.

Conclusions:

The Z-score nomograms derived by this study may be better alternatives to the Western nomograms for use in India and other developing countries for preprocedural decision making in the pediatric population. However, they will require validation in large-scale studies before they can become clinically applicable.

Novel Genetic Variants in BAG3 and TNNT2 in a Swedish Family with a History of Dilated Cardiomyopathy and Sudden Cardiac Death

Familial dilated cardiomyopathy is a rare cause of dilated cardiomyopathy (DCM), especially in childhood. Our aim was to describe the clinical course and the genetic variants in a family where the proband was a four-month-old infant presenting with respiratory problems due to DCM. In the family, there was a strong family history of DCM and sudden cardiac death in four generations. DNA was analyzed initially from the deceased girl using next-generation sequencing including 50 genes involved in cardiomyopathy. A cascade family screening was performed in the family after identification of the TNNT2 and the BAG3 variants in the proband. The first-degree relatives underwent clinical examination including biochemistry panel, cardiac ultrasound, Holter ECG, exercise stress test, and targeted genetic testing. The index patient presented with advanced DCM. After a severe clinical course, the baby had external left ventricular assist as a bridge to heart transplantation. 1.5 months after transplantation, the baby suffered sudden cardiac death (SCD) despite maximal treatment in the pediatric intensive care unit. The patient was shown to carry two heterozygous genetic variants in the TNNT2 gene [TNNT2 c.518G>A(p.Arg173Gln)] and BAG3 [BAG3 c.785C>T(p.Ala262Val)]. Two of the screened individuals (two females) appeared to carry both the familial variants. All the individuals carrying the TNNT2 variant presented with DCM, the two adult patients had mild or moderate symptoms of heart failure and reported palpitations but no syncope or presyncopal attacks prior to the genetic diagnosis. The female carriers of TNNT2 and BAG3 variants had more advanced DCM. In the family history, there were three additional cases of SCD due to DCM, diagnosed by autopsy, but no genetic analysis was possible in these cases. Our findings suggest that the variants in TNNT2 and BAG3 are associated with a high propensity to life-threatening cardiomyopathy presenting from childhood and young adulthood.

Tacrolimus Predose Concentration Is Associated With Hypertension in Pediatric Liver Transplant Recipients

BACKGROUND

The aim of the study was to analyze the incidence of hypertension in pediatric liver transplantation (LT) recipients using ambulatory blood pressure measurements (ABPM) and to identify factors associated with hypertension. We also investigated whether hypertension or tacrolimus predose concentration (TAC C0) was associated with increased left ventricular (LV) wall thickness.

PATIENTS AND METHODS

On a retrospective longitudinal base, we included 39 pediatric LT recipients. Median time since transplantation was 65 months (range: 11-183). Two consecutive ABPM were analyzed with a median time interval of 13 months. Data from echocardiographic evaluation parallel to the baseline ABPM were analyzed. All patients except 1 were prescribed tacrolimus. The median TAC C0 was 4 ng/mL (range 0.9-11.2). Univariate and multivariate logistic regression models were fitted to identify factors associated with systolic and diastolic hypertension and LV wall thickness.

RESULTS

Twenty-two of 39 children were hypertensive at baseline and 19 of 32 were hypertensive at follow-up. At baseline 10 (26%) children had masked systolic hypertension. TAC C0 was associated with systolic (P = 0.007, Exp(B) 2.02, 95% CI 1.2-3.3) and diastolic (P = 0.044, Exp(B) 1.48, 95% CI 1.0-2.2) hypertension. LV wall thickness was increased in children after LT compared with healthy population, but it was not associated with hypertension or TAC C0.

CONCLUSIONS

Given the high prevalence of masked hypertension, ABPM should be performed in all pediatric LT recipients. Systolic and diastolic hypertension is associated with TAC C0; therefore, children with a higher target TAC C0 require a more intensive blood pressure surveillance.

Assessment of the structure and function of the aorta by echocardiography

Echocardiography is the primary modality for imaging the aorta for the diagnosis and serial evaluation of pathological conditions. In this article, we review the methodology for optimal echocardiographic imaging of the various segments of the aorta and discuss abnormalities of the aorta including stenosis, dilation including aortopathy and sinus of Valsalva aneurysms, and fistulous communications involving the ascending aorta including aortoventricular tunnel and ruptured sinus of Valsalva aneurysm. We review novel echocardiographic measurements of aortic functional properties of the aorta such as elasticity and stiffness, and review the literature on the potential additive value of such measurements for structural assessment alone. Finally, we discuss the limitations of echocardiography in the precise and optimal imaging of the aorta.

Echocardiography of coarctation of the aorta, aortic arch hypoplasia, and arch interruption: strategies for evaluation of the aortic arch

Aim Echocardiography is the modality of choice for the diagnosis and serial follow-up of aortic arch pathology. In this article, we review the types of obstruction of the aortic arch, various classification schemes of coarctation of the aorta and interrupted aortic arch, methodology for optimal echocardiographic imaging of the aortic arch, and key echocardiographic measurements for accurate diagnosis of obstruction and hypoplasia of the aortic arch. Finally, we will discuss the limitations of echocardiography in optimal imaging of the aortic arch and the use of other non-invasive imaging modalities such as CT or MRI to provide additional information in these cases.

BACKGROUND

Coarctation of the aorta is the more common lesion of the two, with an estimated incidence of four in every 10,000 live births in the United States of America. Interrupted aortic arch is rarer, with an incidence of 19 per one million live births. 1 There is a spectrum of pathology of obstruction of the aortic arch, ranging from coarctation of the aorta with and without hypoplasia of the arch to interrupted aortic arch. Both these lesions are frequently encountered in congenital cardiology practice, and will be discussed in the remainder of this article. Obstruction of the aortic arch in the setting of hypoplastic left heart structures or atresia of the aortic valve is beyond the scope of this review and will not be discussed further.

Insights into mildly dilated cardiomyopathy: temporal evolution and long-term prognosis

AIMS

Mildly dilated cardiomyopathy (MDCM) has been proposed as a subtype of dilated cardiomyopathy (DCM) characterized by systolic dysfunction in the absence of significant LV dilatation. Few data on the characteristics and outcomes of MDCM patients are available. We sought to assess the main features and the long-term natural history of MDCM.

METHODS AND RESULTS

From 1988 to 2010 we analysed all DCM patients consecutively evaluated at our Institution. MDCM was defined as LVEF <45% and LV end-diastolic volume index (LVEDVI) ≤70 mL/m² in women and ≤89 mL/m² in men. Among a total population of 638 patients, 226 (35%) fulfilled the criteria for MDCM. Compared with the other patients, they presented features of a less advanced disease and an overall long-term lower rate of all-cause mortality/heart transplantation (D/HTx; total events = 209; 144 deaths, 65 HTx): D/HTx at 10 years 15% in MDCM vs. 30% in DCM (P < 0.001). However, throughout the follow-up, 55 MDCM patients (24%) evolved to DCM by increasing LVEDVI, consistently worsening their long-term prognosis. Among persistent MDCM patients, a restrictive filling pattern [hazard ratio (HR) 5.30; 95% confidence interval (CI) 2.34-12.01, P < 0.001] and non-sustained ventricular tachycardia (HR 2.21; 95% CI 1.003-5.11, P = 0.047), but not LVEF, were independently associated with D/HTx at multivariate analysis [time-dependent receiver operating characteristic (ROC) curve: area under the curve (AUC) 0.80, 95% CI 0.65-0.94, P = 0.003].

CONCLUSIONS

MDCM identifies a consistent subgroup of DCMs diagnosed in an earlier stage and presenting an apparent better evolution. However, some MDCMs evolve into DCM despite medical therapy, whereas persistent MDCMs with non-sustained ventricular arrhythmias and restrictive filling pattern are characterized by a very poor outcome.

Transcatheter stenting of the right ventricular outflow tract augments pulmonary arterial growth in symptomatic infants with right ventricular outflow tract obstruction and hypercyanotic spells

We retrospectively reviewed all the children with right ventricular outflow tract obstruction, hypoplastic pulmonary annulus, and pulmonary arteries who underwent stenting of the right ventricular outflow tract for hypercyanotic spells at our institution between January, 2008 and December, 2013; nine patients who underwent cardiac catheterisation at a median age of 39 days (range 12-60 days) and weight of 3.6 kg (range 2.6-4.3 kg) were identified. The median number of stents placed was one stent (range 1-4). The median oxygen saturation increased from 60% to 96%. The median right pulmonary artery size increased from 3.3 to 5.5 mm (-2.68 to -0.92 Z-score), and the median left pulmonary artery size increased from 3.4 to 5.5 mm (-1.93 to 0 Z-scores). Among all, one patient developed transient pulmonary haemorrhage, and one patient had pericardial tamponade requiring drainage. Complete repair of tetralogy of Fallot +/- atrioventricular septal defect or double-outlet right ventricle was achieved in all nine patients. Transcatheter stent alleviation of the right ventricular outflow tract obstruction resolves hypercyanotic spells and allows reasonable growth of the pulmonary arteries to facilitate successful surgical repair. This represents a viable alternative to placement of a systemic-to-pulmonary artery shunt, particularly in small neonates.

The comparative role of echocardiography and MRI for identifying critical lesions in patients with single-ventricle physiology, before bidirectional cavopulmonary connection

BACKGROUND

In the era of multi-modality imaging, this study compared contemporary, pre-operative echocardiography and cardiac MRI in predicting the need for intervention on additional lesions before surgical bidirectional cavopulmonary connection.

METHODS

A total of 72 patients undergoing bidirectional cavopulmonary connection for single-ventricle palliation between 2007 and 2012, who underwent pre-operative assessment using both echocardiography and MRI, were included. The pre-determined outcome measure was any additional surgical or catheter-based intervention within 6 months of bidirectional cavopulmonary connection. Indices assessed were as follows: indexed dimensions of right and left pulmonary arteries, coarctation of the aorta, adequacy of interatrial communication, and degree of atrioventricular valve regurgitation.

RESULTS

Median age at bidirectional cavopulmonary connection was 160 days (interquartile range 121-284). The following MRI parameters predicted intervention: Z score for right pulmonary artery (odds ratio 1.77 (95% confidence interval 1.12-2.79, p=0.014)) and left pulmonary artery dimensions (odds ratio 1.45 (1.04-2.00, p=0.027)) and left pulmonary artery report conclusion (odds ratio 1.57 (1.06-2.33)). The magnetic resonance report predicted aortic arch intervention (odds ratio 11.5 (3.5-37.7, p=0.00006)). The need for atrioventricular valve repair was associated only with magnetic resonance regurgitation fraction score (odds ratio 22.4 (1.7-295.1, p=0.018)). Echocardiography assessment was superior to MRI for predicting intervention on interatrial septum (odds ratio 27.7 (6.3-121.6, p=0.00001)).

CONCLUSION

For branch pulmonary arteries, aortic arch, and atrioventricular valve regurgitation, MRI parameters more reliably predict the need for intervention; however, echocardiography more accurately identified the adequacy of interatrial communication. Approaching bidirectional cavopulmonary connection, the diagnostic strengths of MRI and echocardiography should be acknowledged when considering intervention.

Aortic root dilatation in the children and young adults: prevalence, determinants, and association with target organ damage

Aortic root dilatation is associated with increased cardiovascular risk in hypertensive adults. In the young, few data have been published evaluating the cardiovascular organ damage that may be present in patients with aortic dilatation. The objective was to evaluate the prevalence of proximal aorta dilatation, its possible determinants, and its relation with target organ damage in young subjects. The aorta was measured at the level of the sinus of valsalva and at its proximal ascending aorta (pAA) in a total of 177 young subjects (11-35 years). Linear regression analysis was used to assess the association between aortic size, clinical, and hemodynamic parameters. Prevalence of pAA and sinus of valsalva dilatation was 10.2% and 8.7%, respectively. No significant differences in prevalence were found in hypertensive, diabetic and obese subjects; aortic enlargement was less frequent in African-Americans. Age, sex, and central pulse pressure were the most important determinants of aortic size. Left ventricular mass was increased in patients with aortic enlargement, and aortic size showed an inverse relation with indices of local distensibility. The prevalence of aortic dilatation among young patients is high (10%). As in adults, age and body surface area are the main determinants of aortic size. Dilatation of the ascending aorta is associated with an increased left ventricular mass, as in adults, but not with increased arterial stiffness. Local distensibility is reduced in patients with pAA enlargement.

NT-proBNP and diastolic left ventricular function in patients with Marfan syndrome

AIMS

Subclinical diastolic dysfuntion in patients with preclinical heart failure with preserved ejection fraction (HFpEF) has been demonstrated in patients with Marfan syndrome (MFS). We investigated the relationship between diastolic dysfunction and NT-proBNP levels in patients with MFS.

METHODS AND RESULTS

NT-proBNP, C-reactive protein (CRP) and diastolic function were assessed in 217 patients with MFS (31 ± 16 y, 110 f. and in 339 patients referred for suspected MFS in whom the diagnosis was ruled out according to the Ghent nosology (30 ± 15 y, 154 f). Assessment of cardiovascular remodeling, diastolic function in echocardiography, and NT-proBNP was analyzed with univariate analysis and multi-parameter analysis of covariance (MANCOVA). NT-proBNP was 70.6 ± 74.8 pg/ml in patients with Marfan syndrome and 58.4 ± 100.3 pg/ml in controls (p = 0.002, Kolmogorov-Smirnov). There were significant intergroup differences regarding end-diastolic left ventricular volume (p < 0.001), and aortic diameter (p < 0.001). The ratio of early diastolic mitral flow velocity (E) to early relaxation velocity in tissue Doppler (e'), E/e' (p < 0.001) was significantly higher in patients with Marfan syndrome than in controls, whereas e' (p < 0.001) and the ratio of E to inflow velocity during atrial contraction (A), E/A (p = 0.012) was significantly lower. Besides age and gender, diagnosis of MFS, diastolic function (e' and E/e'), Z-Score of aortic diameter, and left ventricular size were identified as significant independent parameters with impact on NT-proBNP levels.

CONCLUSIONS

MFS patients presenting with normal ejection fraction show disturbed diastolic function and higher NT-proBNP levels, which is partly explained by aortic Z-score. Assessment of diastolic function and NT-proBNP levels may therefore detect early abnormalities and guide surveillance and prevention management of patients with MFS.

Outcome of aortic arch reconstruction in infants with coarctation: Importance of operative approach

OBJECTIVES

Coarctation with hypoplastic aortic arch can be treated with resection and extended end-to-end anastomosis (REEEA) as well as end-to-side anastomosis (ESA). The aim of the study was to review our experience with these techniques in newborns and infants and to assess mid-term outcome with regards to morbidity, mortality, and reintervention rate in relation to operative access and technique.

PATIENTS AND METHODS

Retrospective review of hospital charts and surgical reports from 183 consecutive newborns and infants with coarctation and hypoplastic aortic arch with or without ventricular septal defect between 1996 and 2013. Median age at surgery was 15 days (0-345). Lateral thoracotomy was used as operative access in 111 patients; 72 patients had a median sternotomy, 71 of them with cardiopulmonary bypass (ESA n = 30, REEEA n = 41). Fifty-two patients (28.4%) had an additional ventricular septal defect closure. Follow-up data were available for 75.96% with a median follow-up of 6.3 years (0.2-18.16 years).

RESULTS

Thirty-day mortality was 0.54% with no late mortality occurring during follow-up. There was 1 severe complication: paraplegia and cerebral hypoxemia after REEEA. Freedom from mortality and reintervention at 10 years was 99.27% and 90.12%, respectively. Lateral thoracotomy as operative access was a risk factor for recurrent obstruction (P = .03).

CONCLUSIONS

REEEA and ESA were safe and effective treatments in newborns and infants. In borderline cases, aortic arch reconstruction should be performed through a median sternotomy on bypass.

Out of proportion proximal aortic remodeling: A subclinical marker of early vascular ageing? A systematic review

INTRODUCTION

Proximal aorta stiffens and dilates with aging. Aortic stiffening is a well known process, carrying prognostic implications. On the contrary, few data are available about proximal aorta dilatation. It is not known if "out of proportion" aortic remodeling, i.e. in excess for age, sex and body size, could be a marker of early vascular ageing; there is controversy on how it would be accelerated by classical risk factors or would associate with validated markers of cardiovascular organ damage.

AIM

We conducted a systematic review in order to evaluate the determinants of proximal aortic dimensions, focusing on the association with arterial hypertension, cardiovascular risk factors and markers of organ damage.

DETERMINANTS OF PROXIMAL AORTA REMODELING

Age, gender and body size explain 40-50% of the variability of aortic dimensions; genetic predisposition accounts for nearly 20%. Among cardiovascular risk factors obesity and hypertension seem to be associated with faster outward aortic remodeling. Arterial hypertension would account for a 0.60-0.78 mm greater diameter at the ascending aorta. Moreover, in hypertension, left ventricular mass showed a strict association with aortic diameter in nearly all studies. Other classical risk factors for atherogenesis such as dyslipidemia and smoking showed a weak influence on proximal aortic dimensions. No study reported a greater aortic remodeling in diabetics.

CONCLUSIONS

"Out of proportion" proximal aortic remodeling, could represent a subclinical marker of early vascular ageing, describing the cumulative influence of genetic predisposition, arterial hypertension and obesity.

The mid-term outcome of primary open valvotomy for critical aortic stenosis in early infancy - a retrospective single center study over 18 years

Background

The objective of this study was to examine early and long-term results of surgical aortic valvotomy in neonates and infants aged less than four months and to identify predictors of outcome.

Methods

Between August 1994 and April 2012, 83 consecutive patients younger than 4 months of age underwent open heart valvotomy for critical aortic stenosis in our institution. Median age was 17 days (range 0-111 days). We examined clinical records to establish determinants of outcome and illustrate long-term results.

Results

Fifty-six patients (67 %) were neonates. Associated cardiac malformations were found in 24 patients (29 %), including multilevel left heart obstruction in 5. The median follow-up was 4.2 years. The time-related survival rate was 87 and 85 % at 5 and 15 years, respectively. The time-related survival without reintervention was respectively 51, 35 and 18 % at 5, 10 and 15 years. The time-related survival without aortic valve replacement was respectively 67, 54 and 39 % at 5, 10 and 15 years. Ventricular dysfunction (p = 0.04), delayed sternal closure (p = 0.007), endocardial fibroelastosis (p = 0.02) and low z-score of the aortic annulus (p = 0.04) were found predictors of global mortality. Ventricular dysfunction (p = 0.01) and endocardial fibroelastosis (p = 0.04) were found predictors of reintervention.

Conclusions

The experience, in our center, on the management of critical aortic stenosis, shows a low early and late mortality, but the aortic valvotomy is a palliative procedure and we see unfortunately a high rate of reintervention among which the aortic valve replacement. These results suggest to reconsider the use of aortic balloon valvotomy, and particularly for the neonates with a low cardiac output in order to avoid the myocardial stress and the neurological injury due to the cardiopulmonary bypass.

Coronary Artery Dilatation in Viral Myocarditis Mimics Coronary Artery Findings in Kawasaki Disease

Coronary artery (CA) dilatations are typical to Kawasaki disease (KD) in the pediatric population. CA involvement is a useful feature to help establish the diagnosis of KD. Since myocarditis is omnipresent in the acute phase of KD, we sought to investigate whether viral myocarditis may cause CA dilatation. This retrospective study reviewed 14 consecutive patients diagnosed with acute myocarditis at CHU Sainte-Justine, Montreal. KD diagnosis was excluded for all patients. All echocardiography studies were reviewed by an independent experienced echocardiographer for CA size and myocardial function parameters. CA involvement was classified under three categories: definite dilatation (Z-score ≥2.5 in one or more CA), occult dilatation (Z-score variation ≥2 points for the same CA on two different echocardiograms, but maximum Z-score always <2.5), and no dilatation otherwise. Demographics, laboratory values, microbial etiology testing, and diagnostic studies were collected from medical records. Mean age at presentation was 1.67 ± 3.22 years, where 11/14 (78 %) presented with acute and three with subacute myocarditis. Five (36 %) patients had normal CA measurements, six (43 %) had occult dilatation, and three (21 %) had definite dilatation. Maximal CA Z-score was within the first 8 days of presentation. Patients with viral myocarditis can present CA dilatation during the acute phase of the illness. This finding should be taken into account when KD diagnosis is being based on the CA involvement as the two illnesses may present with similar features.

Effectiveness of Balloon Angioplasty in Children With Recurrent Aortic Coarctation Depends on the Type of Aortic Arch Pathology

OBJECTIVES

The aim of this study was to evaluate the effectiveness of balloon angioplasty (BAP) for recurrent aortic coarctation (ReCoA) in infants comparing simple and complex type of aortic arch pathology (Norwood I procedure).

BACKGROUND

ReCoA is a known complication after cardiovascular surgery for coarctation of the aortic arch.

METHODS AND RESULTS

In a single center case study, we analyzed 20 infants undergoing BAP for ReCoA comparing simple (n = 10) and complex type of aortic arch pathology (n = 10). At catherization diameter of ReCoA stenosis was 3.2 ± 0.7 mm (mean ± SD) with short localized (11/20) or long hypoplastic stenosis (9/20) before and 4.8 ± 1.2 mm after BAP (P < 0.001). Invasive systolic pressure gradient was reduced from 27.5 ± 16.2 mmHg before to 5.1 ± 6.6 mmHg after BAP (P < 0.001), comparable in simple and complex type of ReCoA. At day 1 after catherization noninvasive systolic arterial blood pressure gradient was reduced from 20.2 ± 23.1 to 6.7 ± 9.9 mmHg (P < 0.001), respectively, calculated continuous wave Doppler echo gradient from 36.3 ± 22 to 16.8 ± 9.6 mmHg (P < 0.01). Complications were aortic arch dissection (1/20), discrete aortic arch aneurysm formation (1/20), pericardial effusion (1/20), and peripheral arterial thrombosis (4/20). At a mid-term follow up of 9.5 months (1-40) after BAP, 3 infants needed early surgical reintervention due to secondary ReCoA, all with long hypoplastic aortic arch segments, but simple type of aortic arch pathology.

CONCLUSIONS

At mid-term follow up, BAP remains an effective catheter intervention for ReCoA for infants with localized ReCoA, but not with long hypoplastic aortic arch segments, even in simple type of aortic arch pathology.

Natural History of Dilated Cardiomyopathy in Children

Background

The long‐term progression of idiopathic dilated cardiomyopathy (DCM) in pediatric patients compared with adult patients has not been previously characterized. In this study, we compared outcome and long‐term progression of pediatric and adult DCM populations.

Methods and Results

Between 1988 and 2014, 927 DCM patients were consecutively enrolled. The pediatric population (aged <18 years at enrollment) included 47 participants (5.1%). At presentation, the pediatric population compared with adult patients had a significantly increased occurrence of familial forms (P=0.03), shorter duration of heart failure (P=0.04), lower systolic blood pressure (P=0.01), decreased presence of left bundle‐branch block (P=0.001), and increased left ventricular ejection fraction (P=0.03). Despite these baseline differences, long‐term longitudinal trends of New York Heart Association class III to IV, left ventricular dimensions, left ventricular ejection fraction, and restrictive filling pattern were similar between the 2 populations. Regarding survival analysis, because of the size difference between the 2 populations, we compared the pediatric population with a sample of adult patients randomly matched using the above‐mentioned baseline differences in a 3:1 ratio (141 adult versus 47 pediatric patients). During a median follow‐up of 110 months, survival free from heart transplantation was significantly lower among pediatric patients compared with adults (P<0.001). Furthermore, pediatric age (ie, <18 years) was found to be associated with an increasing risk of both death from pump failure and life‐threatening arrhythmias.

Conclusions

Despite the pediatric DCM population having higher baseline left ventricular ejection fraction and similar long‐term echocardiographic progression compared with the adult DCM population, the pediatric DCM patients had worse cardiovascular prognosis.

Elevated Blood Pressure with Reduced Left Ventricular and Aortic Dimensions in Adolescents Born Extremely Preterm

OBJECTIVE

To evaluate the long-term cardiovascular effects of extremely preterm birth in a cohort of adolescents followed prospectively, who were largely free from intrauterine growth restriction.

STUDY DESIGN

Central blood pressures, aortic and cardiac dimensions, left ventricle (LV) function, pulse wave velocity, augmentation index, and microvascular reactive hyperemia were measured in 18-year-old subjects born extremely preterm at <28 weeks' gestation (n = 109) and term-born controls (n = 81).

RESULTS

Compared with controls, preterm adolescents had higher systolic (124 ± 13 vs 118 ± 10 mm Hg, P = .002) and diastolic (72 ± 8 vs 67 ± 7 mm Hg, P < .001) blood pressures, but lower ascending aortic z-scores (0.13 ± 0.89 vs 0.42 ± 0.78, P = .02), LV diastolic (48.5 ± 4 vs 50.3 ± 4.5 mm, P = .007) and systolic (30.2 ± 3.5 vs 31.9 ± 4.0 mm, P = .003) diameters, and a reduced LV mass (130 ± 34 vs 145 ± 41 g, P = .01) and mass index (75 ± 14 vs 81 ± 16 g/m(2), P = .02). However, LV relative wall thickness, LV function, pulse wave velocity, augmentation index, and microvascular reactive hyperemia were similar. Within the ex-preterm group, there were no significant relationships between birthweight z-scores and any cardiovascular measures, once the latter were adjusted for current body size.

CONCLUSIONS

Extremely preterm birth had relatively minor cardiovascular effects in late-adolescence, with increased blood pressures, decreased LV, and aortic size, but preserved LV function, macrovascular properties, and microvascular function. In utero growth was not independently related to cardiovascular function within the ex-preterm cohort.

Six-Minute Walking Test: Normal Reference Values for Taiwanese Children and Adolescents

BACKGROUND

The 6-minute walking test (6MWT) is a simple method used to evaluate exercise capacity in adults and children with cardiac diseases. Normal reference values in pediatric populations have been reported, but significant variations in the walking distance (6MWD) were noted among different studies. We aimed to provide and validate normal reference values of the 6MWD for healthy Taiwanese pediatric population between 7 and 17 years of age.

METHODS

Healthy children and adolescents were recruited from 13 randomly selected schools in Kaohsiung City. From that recruitment effort, 762 participants (50.1% male) were included, and the 6MWT was conducted using standardized protocols. The main outcome measure utilized was the 6MWD, which was used to construct centile charts and Z score equations. Data from additional 64 healthy volunteers recruited from the National Taiwan University Children's Hospital were used to validate these standards.

RESULTS

There was an overall linear trend of increase in the 6MWD between 7 and 17 years of age (p < 0.001). Males covered significantly more distance than females after the age of 14 years, when the 6MWD essentially plateaued in female adolescents. Upon multivariate analysis, height was the most significant positive predictor of the 6MWD, while body mass index negatively correlated with the 6MWD. The height-based normal reference values of the 6MWD, derived from the 6MWT conducted in the school settings, were validated by a second cohort who received 6MWT inside the hospital.

CONCLUSIONS

Normal reference values of the 6MWD in healthy Taiwanese children and adolescents may serve as useful references for future clinical and research studies.

KEY WORDS

Adolescents; Children; Six-minute walking test; Taiwan.

Hypertrophic cardiomyopathy in Donohue syndrome

We report the case of a patient with Donohue syndrome who died of heart failure due to obstructive hypertrophic cardiomyopathy. A literature survey revealed that hypertrophic cardiomyopathy was present in 30% of these patients and was often fatal. Therefore, every patient with Donohue syndrome should be screened for hypertrophic cardiomyopathy.

Left Ventricular Outflow Tract Obstruction in Aortic Arch Anomalies With Ventricular Septal Defect

BACKGROUND

The predictors of left ventricular outflow tract obstruction (LVOTO) after the repair of coarctation of the aorta or interruption of the aortic arch (CoA/IAA) with ventricular septal defect have been investigated. However, the predictors remain controversial.

METHODS

We performed primary repair of CoA/IAA with ventricular septal defect for 75 patients from 1996 to 2005. Four of the 75 patients died within 5 years after primary repair without relation to LVOTO. The morphology of the aortic valve of 71 survivors was bicuspid in 23 patients and tricuspid in 48 patients. The mean follow-up was 9.2 ± 2.6 years after primary repair.

RESULTS

There were 12 patients who showed LVOTO of 3.0 m/s or greater after primary repair. All of the 6 bicuspid patients demonstrated valvular aortic stenosis, and all of the 6 tricuspid patients showed discrete subvalvular LVOTO. In 5 of the 6 tricuspid patients, the aortic annular z-score before primary repair was -3.0 or less. A bicuspid aortic valve (p = 0.016) and the aortic annular z-score of -3.0 or less (p = 0.019) were significant risk factors for LVOTO after primary repair. At 10 years after primary repair, 82.6% and 95.6% of the bicuspid and tricuspid patients, respectively, were free from reoperation (p = 0.015).

CONCLUSIONS

The presence of a bicuspid aortic valve and an aortic valve annular z-score of -3.0 or less before primary repair are risk factors for LVOTO, and stenotic bicuspid valves and discrete subvalvular LVOTO are the main causes of LVOTO after primary repair of CoA/IAA with ventricular septal defect. The bicuspid patients more frequently required reoperation than the tricuspid patients.

Transposition of the Great Arteries in Fetal Life: Accuracy of Diagnosis and Short-Term Outcome

OBJECTIVE

To review our series of prenatally diagnosed transposition of the great arteries (TGA) to analyze the accuracy of fetal echocardiography for achieving a precise diagnosis of the TGA type (simple vs. complex) and to examine the short-term outcome.

METHODS

A total of 94 cases of simple and complex TGA types (ventriculoarterial discordance with atrioventricular concordance) prenatally evaluated in our referral center between 1998 and 2014 were included. Fetuses with additional congenital anomalies and those with incomplete follow-up were excluded. Prenatal diagnostic accuracy and short-term survival were analyzed for the different types of TGA.

RESULTS

The TGA type was correctly ascertained prenatally in 93.3%. Most fetuses were diagnosed with simple TGA (62.7%). There were 6 discrepancies: 5 fetuses with simple TGA had postnatally TGA + ventricular septal defect (VSD; n = 3) or TGA + VSD + coarctation of the aorta (n = 2), and 1 fetus with TGA + VSD postnatally showed severe left ventricular outflow tract obstruction. The mortality rate was 6.6%; it was higher in complex versus simple forms (12.8 vs. 1.9%, p = 0.038), and in cases with intramural coronary artery versus those without (60 vs. 3.5%, p < 0.001). We found no relationship between the arrangement of the great arteries and coronary arterial abnormalities.

CONCLUSIONS

Simple TGA has a better outcome than the complex forms. A discrepancy rate of 7% with potential influence on the prognosis of survival between the prenatal diagnosis of the TGA type and the definitive diagnosis was found.

Restrictive right ventricular performance assessed by cardiac magnetic resonance after balloon valvuloplasty of critical pulmonary valve stenosis

BACKGROUND

Little data are published about right ventricular diastolic performance in patients with critical pulmonary valve stenosis after balloon pulmonary valvuloplasty thus far.

METHODS

A total of 44 patients with isolated critical pulmonary valve stenosis who had undergone balloon valvuloplasty with haemodynamic recordings were enrolled to the study; 33 patients who came for follow-up underwent further imaging by echocardiography after 6 months and their right ventricular functional parameters were compared with 33 control patients of the same age and sex. Out of 33 patients, 21 underwent cardiac MRI with late gadolinium enhancement to assess the presence of right ventricular fibrosis.

RESULTS

The right ventricular systolic pressure (p<0.0001) and right ventricular outflow tract gradient (p<0.0001) decreased acutely (p<0.0001) after balloon valvuloplasty. During follow-up, M-mode left ventricular end diastolic dimension (p<0.001) and end systolic dimension increased (p<0.001), whereas right ventricular end diastolic dimension decreased (p<0.001). Compared with controls, patients (n=33) had significantly reduced tricuspid annular Ea and higher E/Ea (p<0.001). Right ventricular systolic dysfunction was also suggested by reduced tricuspid annular systolic velocity (p<0.001). Late gadolinium enhancement was demonstrated in 13 out of 21 patients with restrictive physiology, which involves the anterior right ventricular outflow tract, anterior wall, and inferior wall. The right ventricular late gadolinium enhancement score correlated positively with age (r=0.7, p<0.001) and right ventricular mass index (r=0.52, p<0.001).

CONCLUSION

The persistence of right ventricular diastolic dysfunction after relief of chronic pressure overload of critical pulmonary valve stenosis suggests that a factor - other than increase in afterload - is involved in this physiology. Fibrosis is the most likely factor responsible for persistence of restrictive physiology as documented by late gadolinium enhancement.

Evaluation of Cardiovascular Changes in Children with BAVs

The objectives of this study were to investigate left ventricular (LV) function, aortic dilation, and atherosclerosis in children with mildly deteriorated isolated bicuspid aortic valve (BAV) function using echocardiographic studies and biochemical markers of atherosclerosis and to correlate results with normal children. Biochemical analyses indicating cardiovascular risk of atherosclerosis and vascular changes in the aorta in relation to BAV were performed in 41 children aged 5-15 years old with isolated BAV and in 25 children with tricuspid aortic valves. Evaluations of aortic valve structures and functions; examinations of the LV M-mode and ascending aorta Doppler; and measurements of the LV Tei index (MPI), propagation velocity, ascending aorta at four levels, and carotid intima-media thickness (CIMT) were performed. There were no statistically significant differences in CIMTs, plasma matrix metalloproteinase-9, tissue metalloproteinase inhibitor-1 levels, or other biochemical parameters indicating cardiovascular risk or atherosclerosis between study and control groups. Deterioration of LV function, which could not be seen with M-mode echocardiography, was evident by MPI. MPI values in the study versus control groups were 0.46 ± 0.080 versus 0.40 ± 0.086 (p < 0.05). Diameters of the aorta in the study and control groups were 19.7 ± 4.7 and 17.2 ± 2.8 mm (p < 0.05) at the sinotubular junction level and 20.6 (14.4-40.5) and 18.3 (12.4-24) mm at the ascending aorta level (p < 0.05). Increased aortic valve insufficiency was related to increased aortic diameter. No sign of atherosclerosis was detected in children with BAV. Deterioration of LV function was seen using MPI, and aortic dilation was related to the severity of aortic valve insufficiency.

Variable severity of cardiovascular phenotypes in patients with an early-onset form of Marfan syndrome harboring FBN1 mutations in exons 24-32

A subgroup of patients with Marfan syndrome (MFS) who have mutations in exons 24-32 of the FBN1 gene manifests severe atrioventricular valve insufficiency and skeletal problems as early as the neonatal period. These patients usually die in the first 2 years of life, thus a region between exons 24 and 32 of FBN1 is recognized as a critical region for this neonatal form of MFS (nMFS). Here, we report five consecutive patients who manifested a cardiovascular phenotype until infancy with mutations in the critical region for nMFS. Although three of these patients showed severe mitral regurgitation and died before reaching 1 year of age, the remaining two patients survived for over 5 years under medical and/or surgical interventions. Two splicing mutations and one missense mutation were identified in the three deceased patients, whereas two missense mutations were found in the two survivors. Currently, the clinical severity of patients with early-onset MFS harboring mutations in the critical region for nMFS seem to be more variable than ever thought, and intensive treatments are recommended even in this subgroup of patients with MFS.