Medical Therapy Leads to Favorable Remodeling in Left Ventricular Non-compaction Cardiomyopathy: Dilated Phenotype

Left ventricular non-compaction cardiomyopathy (LVNC) is a distinct and heterogeneous entity that can lead to progressive cardiac dysfunction and heart failure. LVNC with dilation and/or dysfunction is associated with a greater mortality risk. We hypothesized that initiation of heart failure medications in patients with LVNC and ventricular dysfunction or dilation would improve systolic function and result in favorable left ventricular remodeling. The study was a retrospective chart review. Inclusion criteria included: presence of LVNC, reduced systolic function or ventricular dilation, therapy with at least one medication (beta blocker, angiotensin-converting-enzyme inhibitor, angiotensin II receptor blocker), imaging pre- and post-initiation of therapy. Fifty-one patients met inclusion criteria. Mean age at initiation of medication was 11.5 ± 11.8 years. Follow-up was 2.4 ± 2.3 years. Three patients (6 %) were solely on a beta blocker, 15 (29 %) on ACE/ARB monotherapy, and 33 (65 %) on dual therapy. At follow-up 45/51 patients (88 %) had improvement in ejection fraction/shortening and 6/51 (12 %) had no change. Ejection fraction, shortening fraction, and left ventricular end-diastolic dimension in the cohort before and after therapeutic intervention demonstrated a 16 ± 12 % improvement in ejection fraction (p < 0.0001), an 8 ± 9 % improvement in shortening fraction (p < 0.0001), and a 0.83 ± 1.93 (p < 0.05) decrease in left ventricular end-diastolic z-score. Early diagnosis and medical treatment of LVNC with reduced systolic function and/or dilation leads to favorable remodeling evident by an improvement in ventricular systolic function and reduction of ventricular end-diastolic dimensions.     

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.     

Echocardiographic Evaluation of Ventricular Function in Children With Pulmonary Hypertension

Although described in adults, it remains unclear whether ventricular dysfunction exists in pediatric patients with pulmonary hypertension (PHN). The goal of this study was to identify differences in echocardiographic indices of ventricular function among pediatric PHN patients. From 2009 to 2011, pediatric PHN patients with normal intracardiac anatomy and age-matched controls (1:3 ratio) were enrolled in this retrospective case–control study. Diagnosis of PHN was based on tricuspid regurgitation velocity or septal position estimating right-ventricular (RV) pressure >50 % systemic. Measures of RV and left ventricular systolic and diastolic function, including tissue Doppler imaging (TDI) of the mitral annulus (MA) and tricuspid annulus (TA), were compared. Enrollees included 25 PHN patients and 75 age-matched controls (mean age 7.5 years [range 1 day to 19 years]). Parameters of RV systolic and diastolic function were worse in PHN patients. Compared with controls, PHN patients had significantly decreased tricuspid valve inflow ratio, decreased TA TDI early diastolic velocities, decreased systolic velocities, increased tricuspid E/E’ ratio (all p < 0.01) and increased myocardial performance index. In an age-stratified analysis, TDI measures in PHN patients <1 year of age were similar to controls, whereas differences in TA TDI velocities and MA TDI velocities were noted in patients ≥1 year of age. Abnormalities in Doppler echocardiographic indices of ventricular systolic and diastolic function were identified in pediatric PHN patients and were more prominent with older age. These indices are promising for serial noninvasive monitoring of disease severity, but further correlation with catheterization-derived measures is needed.     

Correlations Between Echocardiographic Systolic and Diastolic Function with Cardiac Catheterization in Biventricular Congenital Heart Patients

Newer echocardiographic techniques may allow for more accurate assessment of left ventricular (LV) function. Adult studies have correlated these echocardiographic measurements with invasive data, but minimal data exist in the pediatric congenital heart population. Purpose of this study was to evaluate which echocardiographic measurements correlated best with LV systolic and diastolic catheterization parameters. Patients with two-ventricle physiology who underwent simultaneous echocardiogram and cardiac catheterization were included. Images were obtained in the four-chamber view. LV systolic echocardiographic data included ejection fraction, displacement, tissue Doppler imaging (TDI) s′ wave, global longitudinal strain, and strain rate (SR) s′ wave. Diastolic echocardiographic data included mitral E and A waves, TDI e′ and a′ waves, and SRe′ and SRa′ waves. E/TDI e′, TDI e′/TDI a′, E/SRe′, and SRe′/SRa′ ratios were also calculated. Catheterization dP/dt was used as a marker for systolic function, and LV end-diastolic pressure (EDP) was used as a marker for diastolic function. Correlations of the echocardiographic and catheterization values were performed using Pearson correlation. Twenty-nine patients were included (14 females, 15 males). Median age at catheterization was 3.4 years (0.04–17.4 years). dP/dt was 1258 ± 353 mmHg/s, and LVEDP was 10.8 ± 2.4 mmHg. There were no significant correlations between catheterization dP/dt and systolic echocardiographic parameters. LVEDP correlated significantly with SRe′ (r = ?0.4, p = 0.03), SRa′ (r = ?0.4, p = 0.03), and E/SRe′ (r = 0.5, p = 0.004). In pediatric congenital heart patients, catheterization dP/dt did not correlate with echocardiographic measurements of LV systolic function. Further studies are needed to determine which echocardiographic parameter best describes LV systolic function in this population. Strain rate analysis significantly correlated with LVEDP. Strain rate analysis should be considered as an alternative method to estimate LVEDP in this patient population.     

Assessment of Longitudinal Systolic Ventricular Dysfunction and Asynchrony Using Velocity Vector Imaging in Children With a Single Right Ventricle

Assessment of ventricular dysfunction and asynchrony is very important in predicting the outcome for children with a single right ventricle. However, the assessment is inaccurate and subjective because of the unusual ventricular shape. This study aimed to evaluate the feasibility and clinical value of velocity vector imaging for assessing longitudinal systolic ventricular dysfunction and intraventricular asynchrony in children with a single right ventricle. The study enrolled 36 children with a single right ventricle and 36 age-matched children with a normal heart. Peak systolic velocity, peak displacement, strain, strain rate, time to peak systolic velocity, and time to peak systolic strain were measured via velocity vector imaging using the Siemens Sequoia C512 echocardiography instrument. The maximum positive rate of ventricular pressure change (Max [dp/dt]) was obtained by cardiac catheterization for all the children with a single right ventricle. In the children with a single right ventricle, the maximal temporal differences and the standard deviations of the times to peak systolic velocity and peak systolic strain were higher (P < 0.01) than in the children with a normal heart. Moreover, the strain and strain rate values were significantly lower in all six segments (P < 0.05). The strain rate of the basal segment adjacent to the rudimentary chamber correlated best with Max (dp/dt) (r = 0.86; P < 0.01). Longitudinal systolic dysfunction and intraventricular asynchrony could be assessed accurately using velocity vector imaging in children with a single right ventricle.     

Fate of Ventricular and Valve Performance Following Early Bidirectional Glenn Procedure After Norwood Operation Controlled for Hypoplastic Left Heart Syndome Anatomic Subtype

The Norwood operation (NO) with a right ventricle (RV)-to-pulmonary artery (PA) shunt (NRVPA) is reportedly associated with early hemodynamic advantage. Shunt strategy has been implicated in ventricular function. Outcomes after NRVPA compared with classic procedure as part of a strategy involving early bidirectional Glenn (BDG) procedure were analyzed with reference to RV, tricuspid, and neoaortic valve performance. Between January 2005 and December 2010, 128 neonates with hypoplastic left heart syndrome (HLHS) underwent NO. Controlled for aortic/mitral stenosis (AS–MS) subtype, 28 patients underwent NRVPA (group A), and 26 patients had classic procedure (group B). The patients with a non-HLHS single-ventricle anatomy and those who had undergone a hybrid approach for HLHS were excluded from the study. The mean age at NO was 6.8 ± 3.5 days in group A and 6.9 ± 3.6 days in group B. Transthoracic echocardiographic evaluation (TTE) after NO (TTE-1) at the midinterval between NO and BDG (TTE-2), before BDG (TTE-3), before Fontan (TTE-4), and at the last follow-up evaluation (TTE-5) was undertaken. Cardiac catheterization was used to assess hemodynamic parameters before the Glenn and Fontan procedures. The operative, interstage, and pre-Fontan survival rates for AS–MS after NO were respectively 88.1 % (90.3 % in group A vs. 84.7 % in group B; p = 0.08), 82.5 % (82.7 % in group A vs. 81.8 % in group B; p = 0.9), and 80.7 % (79.5 % in group A vs. 81.8 % in group B; p = 0.9). The median follow-up period was 39.6 months (interquartile range 2.7–4.9 months). The RV global function, mid- and longitudinal indexed dimensions, fractionated area change before BDG (TTE-1, TTE-2, TTE-3) and after BDG (TTE-4, TTE-5), and right ventricular end-diastolic pressure did not differ statistically between the groups (p > 0.05). No statistically significant difference in tricuspid or neoaortic intervention was found between the groups (p > 0.05). Controlled for the AS–MS HLHS subtype, shunt strategy showed no midterm survival or hemodynamic (ventricular or valve) impact. At midterm, the follow-up need for neoaortic or tricuspid valve surgical intervention was not affected by shunt selection. The structural ventricular adaptation after reversal of shunt physiology was irrespective of shunt strategy.     

Ratio of Early Diastolic Tricuspid Inflow to Tricuspid Lateral Annulus Velocity Reflects Pulmonary Regurgitation Severity but Not Right Ventricular Diastolic Function in Children With Repaired Tetralogy of Fallot

The current study assessed relationships between the ratio of early diastolic tricuspid inflow to tricuspid lateral annular velocity (tricuspid E/e′) and right ventricular (RV) function in children after tetralogy of Fallot (TOF) repair. The RV function of 25 asymptomatic children with surgically repaired TOF (age 3.3 ± 2.0 years) was assessed by echocardiography and cardiac catheterization. Right ventricular end-diastolic pressure and volume (RVEDP and RVEDV), systolic pressure, and ejection fraction, as well as mean pulmonary arterial pressure, mean right atrial pressure (RAP), and the severity of both pulmonary regurgitation (PR) and tricuspid regurgitation (TR) were assessed in terms of the contribution to tricuspid E/e′. Univariate analysis discovered a relationship between tricuspid E/e′ and RVEDV (R ² = 0172), pressure half-time of PR (PR-PHT) (R ² = 0.173), and TR grade (R ² = 0.145) (p < 0.01 for each). After multivariate adjustment, PR-PHT was significantly associated with tricuspid E/e′ (β = 0.210; p < 0.001). Tricuspid E/e′ was not significantly associated with RVEDP or RAP. In conclusion, tricuspid E/e′ does not indicate RV diastolic function but reflects the severity of PR in asymptomatic children after TOF repair.     

Measurement of Tricuspid Annular Diastolic Velocities by Doppler Tissue Imaging to Assess Right Ventricular Function in Patients with Congenital Heart Disease

We assessed the clinical utility of using diastolic tricuspid annular velocities obtained by Doppler tissue imaging as a noninvasive index of right ventricular function in patients with congenital heart disease. Doppler tissue imaging at the tricuspid annulus and pulsed Doppler echocardiography of the right ventricular inflow were performed in 71 children with congenital heart disease, with and without elevated right ventricular pressure. Cardiac catheterization was performed in all patients with congenital heart disease, and the hemodynamic determinants of the tricuspid annular and inflow velocities were determined. In patients with congenital heart disease, the ratio of the late-to-early diastolic tricuspid annular velocity (Aa/Ea) showed a highly significant correlation with right ventricle pressure/left ventricle pressure (r = 0.79, p < 0.0001), right ventricular end diastolic pressure (r = 0.46, p < 0.0001), and the first derivatives of the change in right ventricle pressure during diastole (r = 0.72, p < 0.0001). However, the late-to-early diastolic tricuspid inflow velocity (A/E) did not correlate with any invasively measured index of right ventricular function. Aa/Ea, derived from tricuspid annular velocities as measured by Doppler tissue imaging, is a valuable, noninvasive tool for detecting an elevated right ventricular pressure in patients with congenital heart disease.     

Early Ventricular Dysfunction After Anthracycline Chemotherapy in Children

The aim of this study was to determine the effect of induction dose of anthracycline chemotherapy on the biventricular function among children with acute hematological malignancies (AHM) using tissue Doppler imaging (TDI) and 2D speckle tracking echocardiography (2D-STE). Thirty pediatric patients with AHM and a mean age of 9.24 ± 4.14 years performed conventional echocardiography, TDI and 2D-STE. After induction chemotherapy, the RV showed mainly a diastolic alteration in its function manifested in significant reduction in the tricuspid TDI-derived E′ and E′/A′ ratio compared with the baseline (20.40 ± 3.81 vs. 17.47 ± 3.87 cm/s, p = 0.001, 1.29 ± 0.27 vs. 1.03 ± 0.37, p < 0.01, respectively), while the TDI-derived RV MPI and isovolumetric relaxation time of RV were significantly increased (0.32 ± 0.06 vs. 0.36 ± 0.08, p < 0.01, 24.73 ± 8.62 vs. 28.47 ± 11.51 ms, p < 0.05, respectively). The LV showed post-chemotherapy mainly an alteration in its longitudinal systolic function in the form of a reduction in MAPSE (13.61 ± 2.00 vs. 11.95 ± 1.75 mm; p < 0.001), TDI-derived systolic velocity of lateral mitral annulus (10.98 ± 2.34 vs. 10.03 ± 1.83 cm/s, p < 0.05), 2D-STE-derived global longitudinal strain (?21.58 ± 2.54 vs. ?19.18 ± 3.59 %, p = 0.001) and 2D-STE-derived global longitudinal strain rate (?1.76 ± 0.22 vs. 1.55 ± 0.29 1/s, p < 0.05), with preservation of LV diastolic function when compared to baseline. TDI and 2D-STE could be used for early detection of anthracycline-induced cardiotoxicity in the pediatric age group. Early after induction chemotherapy, the RV develops mainly diastolic dysfunction, while the LV showed a relative longitudinal systolic impairment.     

Ambulatory Blood Pressure Monitoring in Frequently Relapsing Nephrotic Syndrome

Objectives

To screen patients with frequently relapsing nephrotic syndrome (FRNS) for the presence of ambulatory hypertension and left ventricular hypertrophy.

Methods

Following ethical and parental approvals, consecutive patients with FRNS of ≥2 y duration were enrolled. Those with estimated glomerular filtration rate <60 ml/min/1.73 m² and known familial hypercholesterolemia or diabetes mellitus were excluded. Clinic blood pressure was measured by oscillometry and 24-h ambulatory blood pressure was recorded by Spacelab 90207; echocardiography was done for left ventricular mass. Ambulatory hypertension was defined as the presence of clinic blood pressure >95th centile for age, sex and height, and systolic blood pressure load exceeding 25 %.

Results

Of 99 patients, 73 were boys; their median (IQR) age was 120 (84–156) mo. Clinic blood pressure was >95th percentile in 63 (63.6 %) patients. Ambulatory hypertension was present in 33 (33.3 %), including 14 patients with severe hypertension; 16 (16.1 %) had masked hypertension and 30 (30.3 %) had white coat hypertension. Non-dipping was seen in 72 and 55 patients had high nocturnal systolic blood pressure load. Of 21 patients with increased left ventricular mass index, 9 (42.9 %) had ambulatory hypertension, 3 (14.3 %) had masked hypertension and 6 (28.6 %) patients had white coat hypertension. Compared to those with normal blood pressure, patients with ambulatory hypertension were younger at onset of nephrotic syndrome (odds ratio, OR 0.94; 95 % CI 0.91–0.98; P = 0.002), longer duration of frequently relapsing disease (OR 1.05; 95 % CI 1.00–1.10; P = 0.034) and higher body mass index (BMI) (OR 1.61; 95 % CI 1.07–4.40; P = 0.020). BMI was positively correlated with 24-h systolic blood pressure load (r = 0.23; P = 0.002) and with the left ventricular mass index (r = 0. 57; P = 0.001).

Conclusions

Many patients with FRNS showed high prevalence of clinic, ambulatory and white coat hypertension, emphasizing the need to carefully screen these patients in order to ensure their appropriate management. While clinic blood pressure monitoring detects most patients with hypertension, it misses a significant proportion with masked hypertension, underscoring the need for ambulatory blood pressure monitoring and screening for end organ damage. High BMI was the chief risk factor for hypertension, suggesting that control of overweight and hypertension might improve cardiovascular outcomes.

     

Change in Pediatric Functional Classification During Treatment and Morbidity and Mortality in Children with Pulmonary Hypertension

Despite advances in therapy, outcomes for children with pulmonary hypertension remain poor. We sought to assess the validity of a pediatric-specific functional classification system for pulmonary hypertension (PH) in a heterogeneous population of children with PH diagnosed by echocardiogram or cardiac catheterization. A single-center, retrospective study of 65 infants and children with PH was performed. Pediatric Functional Class (FC) at diagnosis, at last visit, and change in FC over time were evaluated for their association with mortality and PH-associated morbidity in univariate, time-to-event, and multivariate regression analyses. Median age at PH diagnosis was 5.3 months (0 days–12.7 years). Twenty-five children (38 %) had idiopathic PH or PH secondary to congenital heart disease, one (2 %) had left heart disease, and 39 (60 %) had PH secondary to respiratory disease. Mortality was 25 % (16/63), primarily in the first year of follow-up. FC at diagnosis was not significantly associated with survival (p = 0.22), but higher FC (more impaired) at last visit (p < 0.001) and change in FC over time (HR 2.3, 95 % confidence interval 1.3–4, p = 0.0003) were associated with mortality. Higher FC at last visit was associated with greater days of hospitalization in the intensive care unit per year (p = 0.006) and history of cardiac arrest (p = 0.012) and syncope (p = 0.02). Although pediatric FC at diagnosis was not predictive of mortality, response to therapy (as assessed by change in FC over time and FC at last visit) was associated with morbidity and mortality in this heterogeneous cohort. Multicenter prospective studies are necessary to further validate these findings.     

Stenting of the Right Ventricular Outflow Tract in the High-Risk Infant With Cyanotic Teratology of Fallot

Neonatal tetralogy of Fallot (TOF) repair carries an increased risk of low birthweight or premature infants. Studies are investigating stents in the right ventricular outflow tract (RVOT) as an alternative to aortopulmonary shunts. The authors review their institutional experience with RVOT stenting in the high-risk infant with TOF. Data on sequential patients who received RVOT stents were reviewed, with collection of their surgical, echocardiographic, and catheterization data. Size-matched control subjects were identified and outcomes compared. Six infants went to the catheterization lab for RVOT stenting from 2008 to 2010. Five of these patients had placement of an RVOT stent after balloon dilation. The median saturations were 71 % on 48 % fraction of inspired oxygen (FiO₂), with improvement to 94 % (p < 0.001) on 39 % FiO₂ 24 h after stent placement. As shown by echocardiography, the diameter of the median right pulmonary artery (RPA) was 2.6 mm (z-score, ?3.3), and the diameter of the left pulmonary artery (LPA) was 2.0 mm (z-score, ?4.5). Repeat echocardiography before surgery showed a statistically significant increase in RPA and LPA size as well as a modified McGoon ratio (p < 0.05). Four of the five patients subsequently underwent TOF repair. No stent fractures occurred. One patient had repair 10 days after stent placement secondary to stent malposition and tricuspid valve injury. The authors’ experience with stents in the RVOT of TOF patients has yielded good results, with significant improvement in oxygen saturations. Patients had successful elective surgical repair and stent removal without longer cardiopulmonary bypass times or recognizable complications compared with shunted patients.     

Right Ventricular Apical Flattening as an Echocardiographic Screening Tool for Right Ventricular Enlargement

Right ventricular dilation is a common complication after tetralogy of Fallot (TOF) repair. Traditional echocardiographic assessments are imprecise due to the RV’s location and complex geometry. We propose a novel echocardiographic measurement: RV apical flattening (RVAF) as a screening tool to help identify subjects with severe RV dilation. Patients with repaired TOF who had both echocardiograms and CMR’s within 6-month interval at our institution were included in the study. The RVAF was measured in the four-chamber echocardiographic view as the minor length of RV cavity at the level of RV apical endocardium. Subjects were divided into two groups (group I: RVEDVi ≥ 150 ml/m² and group II; RVEDVi < 150 ml/m²). Echocardiogram and CMR data were compared between groups. A total of 75 subjects were included in the study. Mean age was 12.8 ± 3.6 years. Group I had 36 subjects, and group II had 39 subjects. The mean RVAF was significantly higher in group I (2.7 ± 0.5 cm) compared with group II (1.7 ± 0.4 cm; p < 0.001). There was significant correlation between RVAF and RVEDVi (r = 0.81; p < 0.001). By ROC analysis, an RVAF cutoff value of 2.0 cm had 94 % sensitivity and 77 % specificity in identifying severe RV dilation (area under the curve 0.95). RVAF is a simple and effective echocardiographic screening tool to help identify severe RV dilation. In conjunction with other 2D echocardiographic parameters, this technique would help further refine echocardiography-guided patient selection for timing of CMR and pulmonary valve replacement.     

Pulmonary artery pressure evaluated by pulsed Doppler echocardiography in children with a left-to right intracardiac shunt

Summary In a study of 25 children with left-to-right intracardiac shunt we found a good correlation (r>0.92;p<0.001) between right ventricular pre-ejection period/acceleration time, derived from pulsed Doppler echocardiography, and pulmonary artery systolic, diastolic, and mean pressures, measured at cardiac catheterization. This may enhance the noninvasive estimation of pulmonary artery pressure.     

Left Ventricular Tonic Contraction as a Novel Biomarker of Cardiomyopathy in Duchenne Muscular Dystrophy

Dilated cardiomyopathy (DCM) inevitably afflicts patients with Duchenne muscular dystrophy (DMD) as a consequence of cell death induced by unguarded calcium influx into cardiomyocytes. This mechanism may also inhibit muscle relaxation in early stages of cardiomyopathy. ACE inhibition (ACEi) is known to delay the onset and slow the progression of DCM in DMD. The objective of this study is to use echocardiography to assess for preclinical cardiac changes consistent with intracellular calcium dysregulation before the onset of overt ventricular dysfunction, and to evaluate how prophylactic ACEi may alter these pre-cardiomyopathic changes in the pediatric DMD population. We examined 263 echocardiograms from 70 pediatric patients with DMD. We defined abnormal tonic contraction (TC) as left ventricular internal dimension in diastole (LVIDd) Z-score < ?1.5. In our cohort, we found that TC is detectable as early as 8 years of age, and most commonly affects patients between 11 and 15 years. This effect was independent of LV mass and systolic function. Prophylactic ACEi decreased the incidence of TC (p = 0.007) and preserved cardiac function (p < 0.0001). Left ventricular TC often precedes DCM in DMD, most commonly affecting the 11- to 15-year-old age range. TC is not related to ventricular hypertrophy, but rather may be a clinical correlate of the “calcium hypothesis” of DMD pathophysiology. LV TC is thus a promising biomarker for early detection of cardiomyopathy in DMD. ACEi prophylaxis suppresses LV TC and delays the development of DCM in DMD.     

Signal-Averaged Electrocardiogram May Be a Beneficial Prognostic Procedure in the Postoperative Follow-Up Tetralogy of Fallot Patients to Determine the Risk of Ventricular Arrhythmias

Early detection of arrhythmias after congenital heart disease surgery is important because it can help decrease morbidity and mortality. Standard electrocardiograms (ECGs) contain frequencies between 0.05 and 100 Hz, but higher frequencies are also present. Using high-resolution technology, the highest amplitudes of these high-frequency components within the QRS complex can be recorded and analyzed. We studied the relationship between ventricular late potentials, ventricular arrhythmias and right ventricular systolic pressure in 22 patients who underwent tetralogy of Fallot repair (mean follow-up, 40.1 ± 33.5 months). Holter ECG monitoring and signal-averaged electrocardiograms (SAECGs) were performed. SAECG parameters studied included the duration of the filtered QRS, the duration of terminal QRS below 40 μV, and the root mean square amplitude of the terminal 40 msec. Cardiac catheterization was performed on 19 patients. Eighteen healthy volunteers were studied as a control. Ventricular arrhythmias were found in 13 patients; right ventricular systolic hypertension was found in 1 patient. No significant residual ventricular septal defects were detected. Eight patients had ventricular late potentials. Right ventricular systolic pressure did not differ significantly between patients with or without late potentials. There were significant differences between patients with ventricular arrhythmias and healthy volunteers; filtered QRS duration was significantly longer in patients with ventricular arrhythmias. SAECG may be beneficial in determining ventricular arrhythmia risk in tetralogy of Fallot patients postoperatively.     

Decline of Systolic and Diastolic 2D Strain Rate During Follow-Up of HLHS Patients After Fontan Palliation

Accurate assessment of ventricular function is particularly important in children with hypoplastic left heart syndrome (HLHS) after completion of the total cavopulmonary connection (TCPC). For this purpose, two-dimensional speckle tracking (2DST) is a promising technique as it does not depend on the angle of insonation or the geometry of the ventricle. The objective of this study was to assess changes in systolic and diastolic right ventricular (RV) function within a 5-year follow-up period of HLHS patients after TCPC using conventional and 2DST echocardiography. RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), E/A, E/e′ and 2DST parameters [global longitudinal peak systolic strain (GS) and strain rate (GSRs), global strain rate in early (GSRe) and late (GSRa) diastole] of 40 HLHS patients were compared at 1.6 and at 5.1 years after TCPC. RVFAC, E/A, E/e′ and GS did not change, whereas TAPSE (13.7 ± 3.2 vs. 10.5 ± 2.4 mm/m², p < 0.001), GSRs (?1.56 ± 0.28 vs. ?1.35 ± 0.31 1/s, p < 0.001), GSRe (2.22 ± 0.49 vs. 1.96 ± 0.44 1/s, p = 0.004) and GSRa (1.19 ± 0.39 vs. 0.92 ± 0.39 1/s, p < 0.001) decreased significantly. Systolic and diastolic RV function parameters of HLHS patients decreased from 1.6 to 5.1 years after TCPC in our patients. Changes in global strain rate parameters may be signaling early RV dysfunction that is not detectable by traditional echocardiography. Further study is needed to verify this and to determine whether these changes are clinically relevant.     

Echocardiographic Assessment of Right Atrial Pressure in a Pediatric and Young Adult Population

Right atrial pressure (RAP) reflects right-sided cardiac hemodynamics and is useful in management of patients with cardiac and systemic disease. Studies in older adults demonstrated that inferior vena cava (IVC) diameter, IVC collapsibility index, hepatic vein systolic filling fraction (SFF), and right atrial volume (RAV) correlated with mean RAP at catheterization. This study aimed to assess the utility of echocardiographic parameters for assessment of RAP in children and young adults. Patients with pulmonary hypertension or heart transplantation undergoing right heart catheterization were recruited for this prospective observational pilot study. Transthoracic echocardiographic assessment of RAP was performed simultaneously with catheterization. For each parameter, three consecutive cardiac cycles were recorded. Long- and short-axis images of the IVC were obtained. RAV was assessed by area–length and biplane methods. IVC diameters and RAV were indexed to body surface area (BSA)^0.5 and (BSA)^1.4, respectively. Relationships between echocardiographic parameters and mean RAP were correlated using “Pearson’s r.” Fifty subjects aged 0.3–23 years (median 13, mean 12.3 ± 7 years) were enrolled. Mean RAP correlated modestly with RAV (r = 0.51, p < 0.001). Long-axis IVC_max (r = 0.30, p < 0.05) and tricuspid E wave velocity (r = 0.36, p < 0.01) also correlated with mean RAP. RV free wall tissue Doppler velocities, IVC collapsibility index, and hepatic vein SFF had no relation to mean RAP. In a pediatric and young adult population with pulmonary hypertension or heart transplantation, echocardiographic assessment of RAV and long-axis IVC_max provided a reasonable estimate of mean RAP. IVC collapsibility index and hepatic vein SFF demonstrated no association with mean RAP.     

Paradoxical Relationship Between B-type Natriuretic Peptide and Pulmonary Vascular Resistance in Patients with Ventricular Septal Defect and Concomitant Severe Pulmonary Hypertension

B-type natriuretic peptide (BNP) reflects volume overload on left ventricle and pulmonary hypertension (PH) in patients with ventricular septal defect (VSD). Pulmonary vascular resistance (PVR) has been reported to correlate positively with BNP in VSD patients with various degrees of PH. We aimed to investigate the relationship between PVR and BNP in VSD patients with severe PH. We examined 24 subjects with VSD concomitant severe PH aged from 2 months to 17 years (median: 4 months). The ratio of pulmonary to systemic pressure (Pp/Ps), the ratio of pulmonary to systemic flow (Qp/Qs), the ratio of pulmonary to systemic resistance (Rp/Rs), and PVR were determined by cardiac catheterization. PVR and Rp/Rs ranged from 1.6 to 15.5 (mean: 5.7 ± 3.9) Wood unit · m² and 0.1 to 0.8 (mean: 0.4 ± 0.2), respectively. BNP ranged from 5.5 to 69 (mean: 31 ± 19) pg/ml. Negative correlations were observed between BNP and PVR (r = -0.56, p = 0.004) and BNP and Rp/Rs (r = -0.51, p = 0.01). BNP was significantly lower (<10 pg/ml) in VSD patients with Eisenmenger physiology as compared with the others (p = 0.003). We should draw attention to evaluate BNP values in VSD patients with severe PH.     

先天性心脏病肺动脉高压手术前后右心功能变化和治疗

目的 了解先天性心脏病左向右分流导致的重度肺动脉高压对右心功能的影响以及手术矫治后右心功能的恢复状态。方法 对室间隔缺损(室缺)合并重度肺动脉高压(全肺循环阻力增加)的40例患儿，用心导管的方法进行术前、术后5～7年右心功能、肺循环的血流动力学随访测定。结果 术前右心心搏指数、作功指数、心排指数显著高于术后；术前右房压、右室收缩压及舒张压、肺动脉压力和阻力均增高，缺损修补后右室舒张压恢复正常，收缩压的降低与肺动脉压力下降有关；大型室缺左向右分流重度肺动脉高压右心功能不全系继发性右室高排出量心力衰竭，且伴有舒张功能障碍。结论 治疗心力衰竭不宜首选正性心肌收缩药物；降低肺动脉压力、减少左向右分流、根治心内畸形是合理的选择；术后右室收缩压持续不能恢复至正常水平，提示继发性肺血管梗阻性病变存在。