Development of suction force during early diastole from the left atrium to the left ventricle in infants, children, and adolescents.

Although the suction force that moves blood into the left ventricle during early diastole is thought to play an important role in diastolic function, there have been a few studies of this phenomenon in normal children. Suction force is measured as the intraventricular pressure difference (IVPD) and intraventricular pressure gradient (IVPG), which is calculated as IVPD divided by left ventricular length. The purpose of this study was to determine the suction force in infants, children, and adolescents using IVPD and IVPG. We included 120 normal children categorized into five groups based on age: G1 (0-2 years), G2 (3-5 years), G3 (6-8 years), G4 (9-11 years), and G5 (12-16 years). The total, basal, and mid-apical IVPD and IVPG were calculated using color M-mode Doppler imaging of the mitral valve inflow using the Euler equation. The total IVPD increased with age from G1 to G5 (1.75 + 0.51 vs. 2.95 + 0.72 mmHg, respectively; p < 0.001), due to an increase in mid-apical IVPD with constant basal IVPD. Although total IVPG was constant, mid-apical IVPG was larger in G5 than in G1 (0.21 + 0.06 vs. 0.16 + 0.07 mmHg/cm, respectively; p = 0.006). Total, basal, and mid-apical IVPDs were significantly correlated with age and the parameters of heart size and mitral annular e'. Mid-apical IVPG correlated with age and e' positively, but basal IVPG did with age negatively and did not with e'. The suction force increased at the mid-apical segment, correlating with increasing heart size and developing left ventricular relaxation, even after adjustment for left ventricular length.

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.

Assessment of the developmental change in the left atrial volume using real time three-dimensional echocardiography.

AIMS: Real time 3D echocardiography (RT3DE) has been applied for the assessment of left atrial (LA) function in patients with adult heart disease; however, LA function is not well known in children. We aimed at determining the normal range of LA volume (LAV) using RT3DE and the feasibility and reproducibility of this method in healthy subjects and at elucidating the developmental changes in the LAV with aging. METHODS AND RESULTS: In this study, 359 healthy people (mean age, 23.9 ± 21.3; range, 0.1-76.4 years) were enrolled. We performed transthoracic RT3DE and measured the maximum and minimum LAV. Simultaneously, we measured the LAV using the 2D biplane Simpson's method. Inter-observer and intra-observer variability and the agreement of LAV measurements between RT3DE and 2DE were assessed in a subset of subjects. The RT3DE feasibility for LAV measurement was 93%. Both maximum and minimum LAVs exponentially increased with age and linearly increased with increasing of body surface area (BSA). The LA distensibility, which demonstrates LA reservoir function, decreased with age and BSA. The LAVs measured by RT3DE were significantly smaller than those measured by the 2D biplane Simpson's method. The 3D volumetric method had favorable intra-observer and inter-observer agreement. CONCLUSION: The reference values of LAV from early infancy to adulthood were obtained using RT3DE, which could be useful for future studies in children with congenital heart disease. RT3DE is a reproducible method and a feasible tool for evaluating the LAV in children. LA reservoir function is likely to decrease with age and increasing of body size.

Transcatheter Occlusion of a Giant Coronary Artery Fistula in a Neonate.

BACKGROUND Although large coronary artery fistulas are uncommon; they lead to substantial over-circulation in the pulmonary vascular beds and left heart system. Fistula occlusions are achieved via surgical or transcatheter technique; however, reports on successful outcomes of transcatheter treatment during the neonatal period are limited. CASE REPORT A female infant was born at the gestational age of 37 weeks with a birth weight of 2615 grams via normal vaginal delivery. Cardiac auscultation revealed a loud continuous murmur emanating from the fourth right intercostal space. A right coronary artery-to-right ventricle fistula was confirmed using transthoracic echocardiography. The newborn developed respiratory distress 3 days after birth and was administered continuous positive airway pressure to assist breathing. On day 8, the ventilator was used through tracheal intubation due to gradual worsening of dyspnea. A 6-mm Amplatzer Vascular Plug 4 (AGA Medical Corporation, Plymouth, MN) was chosen, as the minimum diameter of the coronary artery fistula was 5 mm. In view of the risk of myocardial ischemia with additional devices, the procedure was stopped despite persistent shunting. The newborn's clinical condition significantly improved following the procedure and she was eventually weaned off ventilator support. CONCLUSIONS A self-expanding occlusion device was useful for relieving this life-threatening condition. Complete elimination of shunting is not always necessary, to avoid compromising myocardial circulation.

A Japanese Patient with Genitopatellar Syndrome Transiently Presenting with Cardiac Intramural Cavity during the Neonatal Period.

Genitopatellar syndrome (GPS) is a rare autosomal dominant disorder caused by de novo pathogenic variants in the KAT6B gene. It is characterized by genital abnormalities, patellar hypoplasia/agenesis, flexion contractures of the hips and knees, corpus callosum agenesis with microcephaly, and hydronephrosis and/or multiple renal cysts. More than half of patients with GPS have congenital heart defects, mostly atrial and/or ventricular septal defects, patent foramen ovale, and patent ductus arteriosus. We report a case of a Japanese neonate with a de novo heterozygous c.3769_3772delTCTA pathogenic variant in the KAT6B gene who presented with a cardiac intramural cavity of the ventricular septum at birth. The cavity unexpectedly disappeared at 1 month of age, but trabecular septal thinning and flash remained. The features of the cavity were not consistent with those of congenital ventricular diverticulum or aneurysm, and its identity and prognosis are still unclear. Because patients with GPS may exhibit various forms of cardiac malformation, careful cardiac examination and follow-up are required from birth in cases of suspected GPS.

Doppler-derived preoperative mitral regurgitation volume predicts postoperative left ventricular dysfunction after mitral valve repair.

BACKGROUND: Unexpected postoperative left ventricular (LV) dysfunction after valve repair for mitral regurgitation (MR) occurs in some patients with normal preoperative LV function. Identification of factors that predispose to such LV dysfunction would enhance our understanding of the indications and outcomes of surgery. METHODS: We retrospectively analyzed pre- and postoperative (median fourth day) echocardiograms of 174 patients undergoing valve repair for pure and isolated MR. Preoperative MR volume was quantified by the quantitative Doppler and/or proximal isovelocity surface area method. RESULTS: There was an incremental predictive value of MR quantification over the current recommendations (global chi(2) from 48.14 to 81.57, P < .001; Hosmer-Lemeshow test, P = .98), for postoperative LV dysfunction, defined as ejection fraction <50%. The independent predictors were MR volume and LV end-systolic dimension (P < .001 and P = .01, respectively). Sixty-nine patients underwent surgery before development of the current surgical criteria, namely, symptoms, atrial fibrillation, preoperative LV dysfunction, or pulmonary hypertension. Of these, MR volume was the only independent significant predictor (P < .001) of unexpected postoperative LV dysfunction that developed in 14 patients (20%). Unexpected LV dysfunction could be predicted with sensitivity of 86% (95% CI 67%-100%) and specificity of 89% (95% CI 81%-97%), using the optimal cutoff of 80 mL for MR volume. CONCLUSIONS: Doppler-derived preoperative MR volume is a powerful predictor of unexpected postoperative LV dysfunction. Prompt mitral valve repair may be beneficial for patients with high likelihood of successful repair and MR volume >/=80 mL.

Left atrial function assessed by real-time 3-dimensional echocardiography is related to right ventricular systolic pressure in chronic mitral regurgitation.

BACKGROUND: Left atrial (LA) volume is a prognostic index in chronic mitral regurgitation (MR). However, little is known about LA function in this setting. We hypothesized that LA dysfunction is related to pulmonary hypertension in chronic MR. METHODS: Seventy-one patients with organic chronic MR who underwent real-time 3-dimensional transthoracic echocardiography (RT3DE) were studied. Left atrial volumes and peak passive and active LA emptying rates were obtained. Total LA emptying fraction was calculated as follows: [(maximum - minimum LA volume)/maximum LA volume] x 100. Similarly, active and passive LA emptying fractions were calculated. From transmitral flow, the peak early (E) and late (A) diastolic filling velocities and E/A ratio were obtained. The early (E') and late (A') diastolic myocardial velocities were obtained by tissue Doppler interrogation of mitral annulus. RESULTS: Effective regurgitant orifice area (EROA) was 0.57 +/- 0.29 cm(2). Right ventricular systolic pressure (RVSP) was measured in 57 patients and averaged 37 +/- 13 mm Hg. Patients with MR and high RVSP displayed higher minimum LA volume, E/A ratio, E/E' ratio, EROA, and MR volume, and lower A' velocity, peak active LA emptying rate, active LA emptying fraction, and total LA emptying fraction than patients with MR and normal RVSP. Multiple regression analysis revealed that EROA (r = 0.51, P = .01) active LA emptying fraction (r = -0.53, P = .02), E/E' ratio (r = 0.50; P = .04), and the lateral A' velocity (r = -0.46; P = .003) were independently correlated with RVSP. CONCLUSIONS: Left atrial function determined by RT3DE had significant correlation with RVSP in chronic MR, irrespective of MR severity. Thus, pulmonary hypertension in chronic MR may depend not only on MR severity but also on LA function.

Geometry of the proximal isovelocity surface area in mitral regurgitation by 3-dimensional color Doppler echocardiography: difference between functional mitral regurgitation and prolapse regurgitation.

BACKGROUND: The geometry of the proximal isovelocity surface area (PISA) of functional mitral regurgitation (MR), which is conventionally assumed to be a hemisphere, remains to be clarified. We investigated the 3-dimensional (3D) geometry of PISA of functional MR as opposed to that of MR due to mitral valve prolapse (MVP) by real-time 3D echocardiography with color Doppler capability. METHODS: Twenty-seven patients with functional MR and 27 patients with MVP were examined. The horizontal PISA length in the commissure-commissure plane and each PISA radius in 3 anteroposterior planes (medial, central, and lateral) were measured by real-time 3D echocardiography with 3D software. The effective regurgitant orifice (ERO) area was calculated with the maximum PISA radius and compared to that by 2D quantitative Doppler method. RESULTS: En-face 3D color Doppler images showed an elongated and slightly curved PISA geometry along the leaflet coaptation in functional MR, whereas the geometry was rounder in MVP. The PISA horizontal length in functional MR was longer than that in MVP (2.3 +/- 0.4 vs 1.2 +/- 0.2 cm, P < .001). The PISA method with the maximum radius underestimated the ERO area by 2D quantitative Doppler method (by 24%) in functional MR, but not in MVP. CONCLUSIONS: The geometry of PISA in functional MR was elongated, distinctly different from the more focal pathology of MVP, leading to underestimation of the ERO area by PISA method.

Preoperative and postoperative mitral valve prolapse and regurgitation in adult patients with secundum atrial septal defects.

BACKGROUND: Little attention is given to development of mitral regurgitation (MR) in adults with atrial septal defect (ASD). The aim of the study was to determine the associated factors of MR in ASD adults before surgical repair and the fate of moderate to severe MR after surgery. METHODS: We examined 71 consecutive patients with secundum ASD (47 +/- 16 years) who underwent surgical repair. Clinical and echocardiographic variables including size of left and right heart systems and severity of MR and tricuspid regurgitation (TR) were investigated before and early after surgery. RESULTS: Before ASD closure, 14 patients (20%) had moderate to severe MR and 25 patients (35%) showed mitral valve (MV) prolapse. The ASD patients with moderate to severe MR showed worse cardiovascular symptoms, increased occurrence of atrial fibrillation and MV prolapse, and greater left ventricular (LV) end-diastolic volume, left atrial area, and TR severity than those with none to mild MR (all P < 0.05). Among preoperative variables, TR severity, left atrial area, LV end-diastolic volume, and MV prolapse were associated with preoperative MR severity in all the patients (all P < 0.03). Isolated ASD closure (n=46) decreased MV prolapse (P=0.008). Preoperative moderate to severe MR decreased after ASD closure with and without MV surgery (n=9 and 5, respectively; both P < 0.05). CONCLUSIONS: Preoperative MR severity was associated with TR severity, dilated left heart chambers, and MV prolapse. MR decreased after ASD closure with and even without MV surgery.

Usefulness of exercise-induced changes in plasma levels of brain natriuretic peptide in predicting right ventricular contractile reserve after repair of tetralogy of Fallot.

Elevated levels of brain natriuretic peptide (BNP) have been associated with ventricular dysfunction, and exercise tests have been used for assessing cardiac contractile reserve. We examined the relation between BNP and right ventricular (RV) contractile reserve during exercise in patients after repair of tetralogy of Fallot (TOF). A total of 45 patients, 26 of whom underwent repair of TOF at 2 to 3 years of age and 19 age-matched healthy children, were studied. Plasma levels of BNP were measured at baseline and at maximal exercise. Echocardiography combined with tissue Doppler imaging (TDI) was performed at rest and during supine bicycle submaximal exercise. The peak value of the first derivation of RV pressure (peak dP/dt) was measured by the continuous-wave Doppler method. The severity of pulmonary regurgitation (PR) (mild, moderate, or severe) was based on color Doppler findings. Plasma BNP levels were significantly higher in patients with TOF than in controls (44 +/- 34 vs 6 +/- 4 pg/ml, p <0.01). Exercise was associated with increased plasma BNP levels in both groups. A larger increment in BNP was noted in patients with TOF than in normal subjects (15 +/- 12 vs 2 +/- 2 pg/ml, p <0.01). The peak systolic myocardial velocity (Sa) and peak dP/dt values increased significantly in both groups during exercise; however, the magnitude of increase in both of these values was significantly less in patients with TOF than in controls (36 +/- 19% vs 70 +/- 19% and 42 +/- 11% vs 81 +/- 12%, respectively; p <0.01). There were significant correlations between the increment in BNP and changes in Sa and peak dP/dt values (r = -0.67 and -0.53, p <0.01, respectively), and the severity of PR (r = 0.74, p <0.01). Thus, exercise increases plasma levels of BNP, and greater increases are associated with impaired RV contractile reserve in patients with TOF with various degrees of PR.

Effects of balloon valvuloplasty on left anterior descending coronary artery blood flow in a neonate with critical aortic stenosis with transthoracic doppler echocardiography.

Doppler echocardiography has recently been used in the assessment of coronary flow dynamics. We described the application of transthoracic Doppler echocardiography for the measurement of the coronary flow before and after balloon valvuloplasty in a neonate with critical aortic stenosis. In this case, coronary flow volume/left ventricular mass ratio increased after the procedure, suggesting the improvement of myocardial blood perfusion. Thus, this technique may provide additional information about coronary flow dynamics in patients with critical aortic stenosis.

Assessment of right ventricular function during exercise with quantitative Doppler tissue imaging in children late after repair of tetralogy of Fallot.

Doppler tissue imaging (DTI) has been developed to assess ventricular wall-motion velocity quantitatively for patients with various types of heart disease. This technique has a possibility of assessing right ventricular (RV) function reserve during exercise. To investigate RV function during exercise using DTI, 21 patients (9.3 +/- 3.3 years) who had undergone operation for tetralogy of Fallot at 1 to 3 years of age and 19 age-matched healthy children were studied. Echocardiography combined with DTI was performed at rest and during supine bicycle submaximal exercise. DTI of tricuspid annulus movement during systole (Sa) was obtained from a 4-chamber view. RV pressure was estimated by maximal tricuspid regurgitation (TR) velocity. The peak value of the first derivation of RV pressure (peak dP/dt) was measured from the continuous wave Doppler-derived TR profile. Adequate spectral Doppler recordings of TR were obtained in all participants. However, 9 healthy children and 2 patients with tetralogy of Fallot were excluded from the study because of an inability to determine the entire spectral TR velocity envelope during exercise. Therefore, data were analyzed in 29 participants. At rest, the mean RV pressure for patients was higher than that in control subjects (27 +/- 4 vs 18 +/- 3 mm Hg, P <.01). The mean Sa and RV peak dP/dt for patients were lower than those in control subjects (6.7 +/- 1.6 vs 8.8 +/- 1.7 cm/s and 464 +/- 77 vs 550 +/- 80 mm Hg/s, P <.01, respectively). Sa and RV peak dP/dt in the two groups increased significantly during exercise. However, the magnitude of increases in Sa and peak dP/dt was significantly less for patients than in control subjects (37 +/- 16 vs 66 +/- 19% and 42 +/- 10 vs 80 +/- 13%, P <.01, respectively). The magnitude of increase in Sa correlated with that in RV peak dP/dt (r = 0.84, P <.01). Results of DTI show high correlation with RV peak dP/dt during exercise. This technique has a potential as a useful indicator of the effect of exercise on RV systolic function. An insufficient increase in Sa suggests impaired response to exercise of RV in patients with tetralogy of Fallot.

Coronary flow reserve assessment by Doppler echocardiography in children with and without congenital heart defect: comparison with invasive technique.

To evaluate whether transthoracic Doppler echocardiography can reliably measure coronary flow velocity (CFV) and CFV reserve (CFVR) in the left anterior descending coronary artery (LAD) in children, we examined 12 patients who had a history of Kawasaki disease without stenosis or aneurysm formation of coronary artery and 9 patients who had congenital heart disease (ventricular septal defect in 6, patent ductus arteriosus in 2, tricuspid atresia in 1). The pulmonary-to-systemic flow ratio ranged from 1.7 to 2.8. CFV in the proximal LAD was measured by transthoracic Doppler echocardiography at the time of Doppler guidewire examination. CFV in the proximal LAD was measured at baseline and hyperemic conditions by both transthoracic Doppler echocardiography and Doppler guidewire techniques. CFVR was defined as "the ratio of peak hyperemic to basal CFV in the proximal LAD." Clear envelopes of basal and hyperemic CFV in the proximal LAD were obtained in 19 of 21 patients by transthoracic Doppler echocardiography. There was a significant correlation between transthoracic Doppler echocardiography and Doppler guidewire methods for the measurements of CFV (r = 0.84, P <.0001). The mean difference between the 2 methods was -0.5 +/- 5.9 cm/s. CFVR from transthoracic Doppler echocardiography correlated well with that from Doppler guidewire examinations (r = 0.83, P <.0001). The mean difference between the 2 methods was 0.06 +/- 0.24. Noninvasive measurement of CFV and CFVR in the proximal LAD using transthoracic Doppler echocardiography accurately reflects invasive measurement of CFV and CFVR by Doppler guidewire method in pediatric patients with various heart diseases.

Myocardial acceleration during isovolumic contraction as a new index of right ventricular contractile function and its relation to pulmonary regurgitation in patients after repair of tetralogy of Fallot.

BACKGROUND: Myocardial acceleration during isovolumic contraction (IVA) by Doppler tissue imaging has been proposed to be a new index of right ventricular contractile function that is unaffected by ventricular shape or loading conditions. OBJECTIVES: We sought to assess the use of IVA to evaluate right ventricular contractile function. METHODS: In all, 22 pediatric patients with pulmonary regurgitation (PR) after repair of tetralogy of Fallot (TOF) (8 +/- 3 years) and 27 age-matched children were examined. The degree of PR (mild, moderate, and severe) for patients with TOF was on the basis of pulsed and color Doppler findings. Using Doppler tissue imaging, the peak myocardial velocities during early diastole, late diastole, systole, and isovolumic contraction were recorded. RESULTS: Compared with healthy children, Doppler tissue imaging velocities for patients with TOF showed decreased myocardial velocities during early diastole (P =.007), late diastole (P <.0001), systole (P <.0001), and isovolumic contraction (P <.0001). Patients with TOF had a lower IVA when compared with healthy children (P <.0001). There was a stepwise decrease in the IVA from mild to severe PR. We found a significant relationship between the IVA and the degree of PR (r = -0.86, P <.0001). CONCLUSION: The analysis of IVA allows the assessment of right ventricular contractile function for patients with repaired TOF and various degrees of PR.

Altered central aortic elastic properties in Kawasaki disease are related to changes in left ventricular geometry and coronary artery aneurysm formation.

BACKGROUND: Recent evidence has suggested that patients display altered arterial elasticity after Kawasaki disease (KD). However, changes in the elastic properties of the central aorta and their relevance to left ventricular geometry have not been studied in patients after KD with and without coronary artery aneurysms (CAAs). METHODS: Clinical and laboratory characteristics of 75 patients with KD were compared with those of 57 controls. The patients with KD included 17 patients with CAAs and 58 patients without CAAs. Values for aortic stiffness index, aortic distensibility, aortic strain, and left ventricular mass index (LVMI) were retrospectively obtained from echocardiographic measurements of the ascending aorta and left ventricle with noninvasive blood pressure evaluation. RESULTS: Systolic blood pressure, pulse pressure, LVMI, and aortic stiffness index were significantly higher and aortic distensibility and aortic strain significantly lower in patients with KD than in the controls. In patients with KD, age at the time of study, interval between the onset of KD and the initiation of this study, CAAs, and LVMI were significantly associated with aortic stiffness index, aortic distensibility, and aortic strain. Multivariate analysis revealed that CAAs and LVMI were independently relevant to aortic stiffness index and aortic distensibility. CONCLUSIONS: The central aortas of patients after KD have altered elastic properties. CAAs and LVMI are independently correlated with central aortic elasticity.

Echocardiographic predictors for persistent functional mitral regurgitation after aortic valve replacement in patients with aortic valve stenosis.

Moderate functional mitral regurgitation (MR) in patients with aortic valve stenosis (AS) is often left unaddressed at the time of aortic valve replacement (AVR) because it is expected to decrease after AVR. However, some patients have persistent moderate MR after AVR. We sought to determine the preoperative echocardiographic predictor for persistent functional MR after AVR in patients with AS. Pre- and postoperative echocardiograms were reviewed in 110 patients with severe AS and functional MR who underwent AVR without mitral valve (MV) surgery. Fifty-eight patients received concomitant coronary artery bypass graft surgery. In patients with MV tenting, defined as apical displacement of mitral leaflets in the apical 4-chamber view, MV tenting area and tenting height were measured at midsystole. Eighty patients had MV tenting (mean MV tenting area 1.4 +/- 0.5 cm(2), mean MV tenting height 0.8 +/- 0.2 cm) and 30 did not have it before AVR. MR severity decreased in 51 of 80 patients (64%) with MV tenting after AVR and in 25 of 30 patients (83%) without MV tenting (p <0.05). In patients with MV tenting, multivariate analysis revealed that presence of long-term atrial fibrillation and MV tenting area were independent predictors of postoperative MR severity (all p values <0.05). The sensitivity and specificity in predicting persistent moderate MR after AVR were 72% and 82% for MV tenting area >1.4 cm(2). In conclusion, preoperative MV tenting predicts persistent functional MR after AVR in patients with severe AS.