Exercise performance and quality of life following surgical repair of anomalous aortic origin of a coronary artery in the pediatric population

OBJECTIVE

We sought to evaluate exercise performance and quality of life in children after surgical repair of anomalous aortic origin of a coronary artery with an interarterial course.

METHODS

Patients who had surgery from October 2001 to January 2007 were eligible for inclusion. Exercise performance and quality of life were prospectively assessed by maximal exercise tests and age-appropriate questionnaires, respectively. We used t tests to compare pre- and postoperative exercise data and quality-of-life scores to published normative data. We performed linear regression analyses to assess associations between demographic, anatomic, and exercise variables and quality-of-life score.

RESULTS

Of 25/27 patients, 64% were boys, 68% had anomalous right coronary, 32% were asymptomatic. Average age at surgery was 10.8 (+/-4.1) years; median follow-up was 14.5 (2 to 48) months. Postoperative percent-predicted exercise values were: peak heart rate 97 (+/-6), working capacity 91 (+/-15), maximal oxygen consumption 82 (+/-16). In those who had preoperative exercise testing (n = 11), resting and maximal heart rates decreased significantly without significant change in exercise performance. Average child quality of life was 85/100 (+/-13) and parent-proxy 88 (+/-11) compared with normal scores of 83 (+/-15) and 88 (+/-12), respectively.

CONCLUSION

There is mild chronotropic impairment in children and adolescents following anomalous coronary artery repair without a decline in exercise performance. This does not appear to impair their overall quality of life. Because long-term effects on heart rate, exercise performance, and quality of life are unknown, serial exercise tests should be included as routine care of these patients.

Ericifolin: an eugenol 5-O-galloylglucoside and other phenolics from Melaleuca ericifolia

Ericifolin, an eugenol 5-O-beta-(6'-O-galloylglucopyranoside) possessing the naturally unknown phenolic moiety, 5-hydroxyeugenol, together with the two new phenolics, 2-O-p-hydroxybenzoyl-6-O-galloyl-(alpha/beta)-4C1-glucopyranose and 3-methoxyellagic acid 4-O-rhamnopyranoside have been isolated from the antibacterial leaves extract of Melaleuca ericifolia. In addition, 19 known phenolics were also separated and characterized. All structures were elucidated on the basis of analysis of 1H, 13C NMR, HMQC, HMBC and FTMS spectral data.

Left ventricular diastolic dysfunction in congenital chronic anaemias during childhood as determined by comprehensive echocardiographic imaging including acoustic quantification

AIMS

To evaluate prospectively the left ventricular performance in thalassaemia major and sickle cell disease using comprehensive echocardiographic imaging including acoustic quantification during early childhood.

METHODS AND RESULTS

Twenty-three patients with thalassaemia and 26 patients with sickle cell disease underwent echocardiographic examination including M-mode, 2-D, Doppler and acoustic quantification. All patients were matched for age, sex, weight and height with 20 normal controls. All patients were below 13 years of age. Thalassaemia and sickle cell disease patients were significantly anaemic when compared with normals (P<0.0001). All patients had normal left ventricular systolic parameters. Acoustic quantification-derived left ventricular volumes, filling rates, and emptying rates were not different in thalassaemia patients from controls. Left ventricular volumes, however, were larger in sickle cell disease patients than in controls. In contrast, by Doppler technique, left ventricular filling occurs mainly in early diastole (E wave) in thalassaemia patients and mainly in late diastole (A wave) in sickle cell disease patients, (P=0.03 and 0.01 respectively). E/A ratio was lower and diastolic filling period was shorter than normal in sickle cell disease but not in thalassaemia patients. Patients in both groups had left ventricular mass (determined by M-mode) significantly higher than normal (P<0.0001).

CONCLUSION

The left ventricular systolic performance is well preserved in patients with chronic anaemia due to thalassaemia major and sickle cell disease during early childhood. In both diseases, however, there is left ventricular hypertrophy and measurable abnormalities in the diastolic filling detected by Doppler. Such changes do not fit a specific cardiomyopathic pattern due to diastolic dysfunction i.e. restrictive physiology vs delayed relaxation. Acoustic quantification of left ventricular diastolic parameters (filling rates) was less sensitive than Doppler in detecting these early diastolic abnormalities in both diseases.

Evidence for autosomal recessive inheritance of infantile dilated cardiomyopathy: studies from the Eastern Province of Saudi Arabia

Familial dilated cardiomyopathy is being increasingly recognized, but affected individuals <10 y are rarely identified. We describe the natural history of dilated cardiomyopathy and evaluate the mode of inheritance among infants of Arab descent from the Eastern Province of Saudi Arabia. We evaluated 55 consecutive cases of dilated cardiomyopathy in patients <10 y of age seen during a 5-y interval. Echocardiography was the primary diagnostic modality. The 55 cases represented 20% of the offspring of 41 families of Arab descent. In 19 families (46%), parents were first cousins; there was no obvious consanguinity in 22 families (54%). Age at presentation was <30 mo (95%) (range, 1 to 100 mo); males (38%) and females (62%) were affected. Patients died (25 patients, 46%), improved (15 patients, 27%), or recovered (15 patients, 27%). The left ventricular shortening fraction at diagnosis ranged from 5 to 28% and did not differ in those who died, improved, or recovered. Complex segregation analysis of the family data using the mixed model of inheritance showed that a model of recessive inheritance best fits the data. Recessively inherited dilated cardiomyopathy has been infrequently reported, perhaps because it may be difficult to recognize in other patient groups in which consanguineous marriage is uncommon and the number of children per family is small. In the setting of consanguineous marriage, homozygosity mapping should lead to identification of the gene(s) causing dilated cardiomyopathy in the families we studied.

Lung perfusion patterns after bidirectional cavopulmonary anastomosis (Hemi-Fontan procedure)

Perfusion lung scans were performed immediately prior to Fontan procedure in 45 patients with a functional single ventricle who underwent the hemi-Fontan procedure as an intermediate stage between the initial palliative shunt procedure and the final complete Fontan anastomosis. Symmetric pulmonary blood flow (PBF) distribution was found in 27% of patients, whereas moderately to severely abnormal PBF distribution was found in 35% of patients. The achieved systemic aortic saturation following the hemi-Fontan procedure was not affected by these abnormalities.

Beat-to-beat variability of left ventricular indexes measured by acoustic quantification: influence of heart rate and respiration--correlation with M-mode echocardiography

Influence of heart rate and respiration on beat-to-beat variability of left ventricular indexes measured by acoustic quantification was examined. These indexes were correlated with their counterparts measured by M-mode echocardiography. Parameters of left ventricular performance were recorded for 1 full minute in 43 children with a mean age of 5.9 +/- 3.9 years. Beat-to-beat variability was documented. The effect of respiration on such variability was examined in another 10 subjects. A wide range of heart rates and respiration did not show significant influence on the degree of variance among these parameters. The indexes measured correlated well with their counterparts measured by M-mode echocardiography. Acoustic quantification separated those with normal from those with abnormal left ventricular function with the same statistical significance as did M-mode echocardiography. A moderate degree of beat-to-beat variability occurs in acoustic quantification-derived left ventricular indexes. Heart rate variability and respiration do not influence the beat-to-beat variance of parameters of left ventricular performance measured with the acoustic quantification. Excellent correlation was documented between this technique and M-mode echocardiography.

Validity of electrocardiographic criteria for left ventricular hypertrophy in children with pressure- or volume-loaded ventricles: comparison with echocardiographic left ventricular muscle mass

To determine the correlation between electrocardiographic (ECG) findings and anatomy utilizing echocardiography in children with pressure- or volume-loaded left ventricles, we analyzed the preoperative ECG tracings of 19 patients who underwent surgery for significant aortic stenosis and 12 patients who underwent cardiac catheterization or surgery for clinically significant ventricular septal defects. We then compared them with a group of 21 normal controls. The left ventricular muscle mass in these patients was calculated from echocardiograms using the simplified cubed formula. Posterior and septal wall thickness and cavity size were significantly greater in the aortic stenosis group than in the normal group. Only cavity size was significantly greater in the ventricular septal defect group than in the normal group. Eighteen aortic stenosis patients (95%) and ten ventricular septal defect patients (83%) had a left ventricular muscle mass greater than 2 standard deviations above the mean for the normal group. Significant differences were found in the voltages of SV1 + RV6 and in the voltage of RV6 alone between normals, aortic stenosis patients, and ventricular septal defect patients regardless of age. Using conventional ECG criteria for left ventricular hypertrophy, the highest sensitivity in aortic stenosis patients (67%) and ventricular septal defect patients (60%) was modest. The likelihood ratio for a positive test in either group was the best for SV1 + RV6 > 98th centile for age; RV6 > 98th centile for age was the best single measurement. No correlation was found between voltage and any measurable hemodynamic or anatomic data. Conventional pediatric ECG criteria for left ventricular hypertrophy have only modest sensitivity regardless of whether the heart is under pressure or volume load. Because left ventricular muscle mass can be precisely determined by echocardiography, these ECG criteria should be applied cautiously.

Relation between age at surgery and regression of right ventricular hypertrophy in tetralogy of Fallot

Pre- and postoperative echocardiographic right ventricular wall thickness (RVW), transverse dimension (RVD), and their ratio (W/D) were measured from subcostal views in 29 patients with Tetralogy of Fallot (TOF) in order to assess whether primary reparative surgery without prior palliative shunts in early infancy results in significantly faster regression of RV hypertrophy than repair later in life. Fourteen patients who were repaired before 6 months of age were compared with 15 patients who were repaired after 6 months of age. In the group of patients who were repaired before 6 months of age both RVW and W/D ratio decreased significantly whereas RVD did not change from pre- to postoperative status. The group of patients who were repaired after 6 months of age showed no significant changes in RVW, RVD, or W/D ratio. These findings suggest that early primary reparative surgery of TOF may have a positive effect on faster regression of RVH during the first postoperative year which may reduce the detrimental effect of longstanding hypertrophy on myocardial function and the potential for arrhythmia.

Changes in right ventricular geometry and heart rate early after hemi-Fontan procedure

To document and quantitate changes in right ventricular (RV) geometry and heart rate, we prospectively examined 35 consecutive patients with hypoplastic left heart syndrome under steady-state conditions (chloral hydrate sedation) before and after a bidirectional cavopulmonary anastomosis (hemi-Fontan) procedure. Right ventricular end-diastolic volume (RVEDV) was calculated as the product of RV cavity areas in two orthogonal planes divided by RV maximal length in either plane. After the hemi-Fontan procedure, RVEDV decreased by 33% from 33 +/- 13 to 22 +/- 11 mL (mean +/- standard deviation). Indexed RVEDV decreased from 86 +/- 37 to 57 +/- 28 mL/m2. The RV wall thickness at the diaphragm in subcostal frontal view (RVWD) increased by only 11% from 8 +/- 0.2 to 9 +/- 0.2 mm (p = not significant), but RVWD/RVEDV increased by 111% from 0.36 +/- 0.22 to 0.76 +/- 0.69 mm/mL (p = 0.002). The RV anterior wall thickness in subcostal sagittal view (RVWA) increased by only 13% from 7 +/- 0.2 to 8 +/- 0.2 mm (p = not significant), but RVWA/RVEDV increased by 103% from 0.31 +/- 0.20 to 0.63 +/- 0.54 mm/mL (p = 0.002). In 11 of 35 patients (31%), resting heart rate did not change (118 +/- 14 versus 108 +/- 9 beats/min; p = not significant); however, in 24 of 35 patients (69%), heart rate increased significantly (108 +/- 9 versus 127 +/- 10 beats/min; p = 0.05). In conclusion, RV wall thickness is high before the hemi-Fontan procedure and increases slightly in the first postoperative week.(ABSTRACT TRUNCATED AT 250 WORDS)

Noninvasive imaging of intraarterial baffles in infants and children

Baffles within the lumen of the pulmonary artery are created in (1) the Aubert procedure, a variation of the arterial switch favored by some surgeons when two major coronary ostia arise close to one another or when one coronary artery has an intramural course, and (2) the Takeuchi procedure, a technique applied to patients with anomalous origin of the left coronary from the pulmonary artery. In both operations, coronary artery transplantation is avoided; instead, an aorticopulmonary window is created and aortic blood is redirected by an intrapulmonary artery baffle into the coronary circulation. We imaged five patients with Aubert and 10 patients with Takeuchi procedures by use of ultrasound to assess the sequelae of such intraarterial baffles. All five Aubert patients were < 3 weeks old; the ages of the 10 Takeuchi patients ranged from 2 to 86 months. Two patients died early after surgery; the remaining 13 patients were observed for 3 to 83 months (median 46 months). In all 15 patients, the baffle geometry was visualized and the aorticopulmonary window was identified. In the six who had serial imaging, none developed aorticopulmonary window stenosis. In no patient was any peribaffle shunting detected. Supravalvar narrowing, caused by the baffle partially obstructing the neopulmonary artery, was observed in two of five Aubert patients; in only one of these has reoperation been performed. In one of the 10 Takeuchi patients supravalvar narrowing of the pulmonary artery (related to repair of coexistent tetralogy of Fallot) has developed and the patient has since undergone reoperation.

Patterns of anomalous pulmonary venous connection/drainage in hypoplastic left heart syndrome: diagnostic role of Doppler color flow mapping and surgical implications

Differentiation between anomalous connection and anomalous drainage of the pulmonary veins in hypoplastic left heart syndrome is important before either the Norwood procedure or heart transplantation is performed. To determine the prevalence of echocardiographically detected anomalous connection or drainage, or both, of pulmonary veins in patients with this syndrome, preoperative two-dimensional echocardiographic and Doppler color flow mapping studies of 317 patients who underwent the stage I Norwood procedure were reviewed. The term "connection" was used to describe the precise anatomic attachment of the pulmonary veins and the term "drainage" to describe the physiologic end point of pulmonary venous flow. Twenty patients (6.3%) had anomalous connection or drainage, or both, of the pulmonary veins by preoperative echocardiographic and Doppler examination. The subcostal and suprasternal scans best showed the anatomic details of the pulmonary veins. All these patterns were confirmed intraoperatively and could be grouped as follows: 1) partial anomalous connection and drainage (two patients); 2) total anomalous connection and drainage (eight patients); 3) normal connection with total anomalous drainage (eight patients); and 4) normal connection with partial anomalous drainage (two patients). The advantage of adding Doppler color flow mapping to two-dimensional echocardiography and conventional Doppler study was clearly demonstrated in the detection of small accessory vertical veins, their course and the presence or absence of obstruction. Doppler color flow mapping was especially helpful in detecting anomalous drainage of the right pulmonary veins to the right of the superior attachment of the septum primum.

Echocardiographic evaluation of the aortic root and mitral valve in children and adolescents with isolated pectus excavatum: comparison with Marfan patients

Pectus excavatum, mitral valve prolapse (MVP), and dilated aortic root occur frequently in patients with Marfan's syndrome (MS). Patients with isolated pectus excavatum (IPE) have a high prevalence of MVP, but it is not known whether aortic root dilatation is a risk in those patients. To test the hypothesis that IPE and MS represent a spectrum of connective tissue dystrophy with MV and aortic root involvement, two-dimensional (2D) echocardiography was used to measure the aortic root diameter and assess for MVP in IPE (n = 31), MS (n = 14), and normal (n = 16) gender- and age-matched patients. Aortic root was measured in parasternal long- and short-axis views, just above the aortic sinuses, at end systole, in six cardiac cycles, and averaged. Parasternal long-axis view was used to assess for MVP. Aortic root diameter in IPE patients was not different from that in normal subjects, 24 +/- 4 mm vs 22 +/- 4 mm (p = NS), respectively, both were significantly smaller than that in MS patients (30 +/- 5 mm; p less than 0.05). MVP was present in 17 of 31 (55%) IPE patients vs 12 of 14 (86%) MS patients (p = NS) and in only 1 of 16 (6%) normal subjects (p less than 0.05) vs both IPE and MS. We conclude that young patients with IPE represent an isolated form of connective tissue abnormality because of the presence of pectus excavatum and MVP, but this is different from the systemic involvement of MS because of the lack of other systemic findings, including aortic root dilatation and changes in body habitus.

Complex ventricular ectopic activity in patients less than 20 years of age with or without syncope, and the role of ventricular extrastimulus testing

To assess the potential for ventricular tachycardia (VT), ventricular extrastimulus testing was performed in 33 young patients with complex ventricular ectopic activity defined as multiform ventricular premature complexes (VPCs), couplets or nonsustained VT, or a combination, found during electrocardiographic monitoring. There were 21 male and 12 female patients with a mean age of 11 years (range 1 to 18). Patients were divided into 2 groups based on the presence (14 patients) or absence (19 patients) of syncope. Patients with syncope had ostensibly normal hearts (9 patients) or miscellaneous heart disease (5 patients). Patients without syncope had ostensibly normal hearts (8 patients) or miscellaneous heart disease (11 patients). Ventricular stimulation protocol consisted of burst pacing and 1 to 4 programmed extrastimuli decreasing to refractoriness at 3 drive-train cycle lengths, and at 2 pacing sites (right ventricular apex and outflow tract) during the drug-free baseline state and isoproterenol infusion. No patient had VT induced with 1 or 2 extrastimuli. VT was induced in 13 of 14 patients (93%) with syncope, and in 9 of 19 patients (47%) without syncope (p less than 0.05). Using a 3-extrastimuli protocol, 8 of 14 patients (57%) with and 3 of 19 patients (16%) without syncope had VT induced (p less than 0.05). These findings suggest that VT may be the cause of syncope in young patients with complex ventricular ectopic activity.

Echocardiographic and color flow Doppler assessment of systemic and pulmonary venous connection and drainage in the neonate with congenital heart disease

Systemic and pulmonary venous anomalies are frequently encountered either as isolated lesions or as a significant component of a more complex lesion in the newborn infant with congenital heart disease. Two-dimensional echocardiography and Doppler techniques (conventional and color flow) have become the primary diagnostic imaging modality in this setting. Precise pre-operative definition of these variable venous connection and drainage patterns is critical as the required surgical procedure may solely be based on exact understanding of the veins' anatomy and physiology. On the systemic venous site, anomalies of superior and inferior venae cavae, innominate vein, and coronary sinus can be equally well imaged with either echocardiography or angiography. However, on the pulmonary venous site, echocardiography and Doppler techniques including color flow mapping are superior to angiography for precise definition of the connection and drainage sites of the individual pulmonary veins.