Repair of anomalous origin of the left coronary artery in the infant and small child.

Anomalous origin of the left coronary artery from the pulmonary artery is associated with myocardial infarction, left ventricular dysfunction, mitral valve dysfunction and, occasionally, intracardiac congenital abnormalities. A technique that utilizes a flap of the anterior wall of the pulmonary artery to serve as a neocoronary artery to direct aortic flow from a created aortopulmonary window to the pulmonary artery orifice of the anomalous left coronary artery was used in five patients aged 2.5 months to 4.75 years. Two patients were less than 4 months of age at operation. There was one death 2 days after operation and one late death. The two youngest patients required mitral valve replacement. Two of the three surviving patients are well at follow-up at 7 to 44 months. One patient has been lost to follow-up study. One patient had postoperative catheterization which showed an intact repair. The pulmonary artery neocoronary procedure is applicable to infants and small patients with anomalous origin of the left coronary artery from the pulmonary artery.

Two-dimensional echocardiography for catheter location and placement in infants and children.

This paper presents our experience with two-dimensional echocardiography in the detection of 61 intravascular catheters or wires in a series of 39 infants and children. It was possible to identify intravascular wires as small as 0.5 mm in diameter and intravascular catheters as small as 0.9 mm in diameter. In no instance, was an intravascular catheter not detected. The two-dimensional echocardiogram is demonstrated to be a tool to assist the physician in placement of intravascular catheters. In the catheterization laboratory, the two-dimensional echocardiogram is useful in determining catheter location, particularly in the presence of complex congenital defects. Two-dimensional echocardiographic guidance of catheters minimizes exposure to ionizing radiation.

Echocardiographically assisted balloon atrial septostomy.

Balloon atrial septostomy is an accepted method for palliation of certain types of congenital heart disease. However, malposition of the balloon may lead to cardiac perforation, avulsion of an atrioventricular valve, or laceration of the systemic or pulmonary veins. Inasmuch as single-phase fluoroscopy may not identify balloon position correctly and as biplane fluoroscopy adds significant radiation exposure, two-dimensional echocardiography has been used to assist in balloon atrial septostomy in ten infants. The catheter is advanced from the inferior vena cava to the right atrium across the foramen ovale to the left atrium with the echo transducer in the subxiphoid position. The balloon is inflated and its position within the left atrium is confirmed by echo. The catheter is withdrawn according to the technique of Rashkind. Withdrawal is halted when the balloon traverses the atrial septum. Adequate septostomy is indicated on echo by a defect at least 5 mm in diameter and by flapping of the inferior rim of the atrial septum. There were no complications using this technique and a clinically adequate septostomy was achieved in each patient. Two-dimensional echocardiography-assisted balloon atrial septostomy minimizes risk of complications and decreases exposure to ionizing radiation.

Critical aortic coarctation: patch aortoplasty in infants less than age 3 months.

Twenty-three infants less than age 3 months (mean age 31 days) underwent patch aortoplasty for relief of coarctation of the aorta. All had intractable congestive heart failure, despite aggressive medical therapy. Each infant had other cardiac anomalies, including patent ductus arteriosus (83 percent) and ventricular septal defect (74 percent). All patients underwent closure of the ductus arteriosus and patch angioplasty of the aorta to produce a luminal diameter of at least 16 mm. In addition, 9 of the 17 patients (53 percent) with a large shunt ventricular septal defect underwent pulmonary arterial banding. There was one hospital death 42 days after operation secondary to bowel perforation and sepsis. Hospitalization beyond 21 days postoperatively was always due to other unrepaired cardiac lesions. The three late deaths at 3, 9 and 18 months after operation were associated with additional major anomalies. Fourteen patients have had postoperative catheterization. No gradient was found across the site of coarctation repair, but one patient had a gradient between the left carotid and left subclavian arteries. Surgical repair of critical coarctation of the aorta in infants can safely be offered despite the presence of other cardiac anomalies.

Left ventricular false tendons in children: prevalence as detected by 2-dimensional echocardiography and clinical significance.

During a 28-month period, consecutive 2-dimensional echocardiograms were reviewed to determine the prevalence of left ventricular (LV) false tendons, their associated anomalies and clinical significance. LV false tendons were found in 31 (0.8%) of 3,847 consecutive 2-dimensional echocardiograms. Of 31 LV false tendons, 30 passed longitudinally from papillary muscle to septum and 1 went from free wall to free wall. The 31 patients were aged 1 day to 15 years. Associated heart disease, most often ventricular septal defect, bicuspid aortic valve and coarctation of the aorta, was present in 48%, of whom 73% were girls. Of those without heart disease, 69% were boys. In patients with heart disease, precordial murmurs were due to the underlying cardiac anomaly. Of those without heart disease, 15 of 16 (94%) had a precordial murmur, usually of the Still's type over the lower left sternal border. Four of 31 (13%), 1 with and 3 without heart disease, had unifocal premature ventricular contractions that were rate-dependent in the 2 patients undergoing stress testing. LV false tendons appear to occur in 0.8% of pediatric patients and usually are accompanied by a Still's type innocent murmur if unassociated with heart disease. Some LV false tendons are associated with rate-dependent premature ventricular contractions.

Small left atrium and change in contour of the ventricular septum in total anomalous pulmonary venous connection: a morphometric analysis of 22 infant hearts.

Morphometric measurements of 22 hearts with total anomalous pulmonary venous connection (TAPVC) were compared with measurements of 8 matched control specimens without heart disease. Each of the TAPVC specimens had a shorter left atrium, smaller left atrial surface area and larger diameter of the fossa ovalis. In addition to increased length of the right ventricle and larger circumferences for tricuspid and pulmonary valve anuli, the left ventricular contour of the ventricular septum was flat or convex in 18 of the 22 hearts; the septum was significantly longer than normal in these specimens and wider at its midportion. Because mitral and aortic valve anuli were normal in circumference, the data suggest that left ventricular volume is not decreased despite change in ventricular shape.

Early failures of Ionescu-Shiley bioprosthesis after mitral valve replacement in children.

Two infants, 101/2 and 11 1/2 months of age, underwent mitral valve replacement with Ionescu-Shiley bovine bioprosthesis for congenital cardiac defects. Both patients had early valve failure, 19 months and 4 months after implantation, due to the growth of excessive collagen on the ventricular surface of the bioprosthesis with adherence of the collagen primarily to the sewing rings and struts of the valves. The cause of this excessive collagen reaction is unknown. Further study is needed to document the true incidence of this problem.

Late complications following surgical repair of total anomalous pulmonary venous return below the diaphragm.

Between May, 1975, and June, 1977, we surgically repaired an infracardiac total anomalous pulmonary venous return in 4 infants under deep hypothermic cardiac arrest. All patients had pulmonary hypertension and a patent ductus arteriosus. All survived operation and required positive end-expiratory pressure with mechanical ventilation. Late complications included patent ductus arteriosus not visualized at initial catheterization, breakdown of an oversewn atrial septal defect repair, and pulmonary venous obstruction despite an anastomosis diamter of 1.5 to 2.5 cm. At reoperation, there was scarring and contraction at the junction of the pulmonary veins and left atrium. One infant with these complications died post-operatively. In another patient, there was kinking of the left lower pulmonary vein at its juncture with the left atrium. In view of these complications we currently recommend the following: ligation of the ductus arteriosus regardless of catheterization findings; a right-sided approach to avoid pulmonary vein kinking; prosthetic patch closure of the atrial septal defect to avoid excessive tension on suture lines and to maintain maximum left atrial size; stellate anastomosis to provide the largest possible drainage channel; awareness that an unusually high positive end-expiratory pressure may be required postoperatively; and early recatheterization.

Fetal echocardiography: a large clinical experience and follow-up.

We reviewed our experience with 382 fetal echocardiograms. Complete studies were not possible for three pregnancies because of either fetal position or maternal obesity. Studies were performed for fetal arrhythmia (28%), maternal factors (21%), fetal anomaly (11%) and family history of congenital heart disease (40%). There was a recurrence of heart disease in two of 153 patients (1.3%). Arrhythmia was the most common finding (82 of 382 patients). Premature atrial and ventricular contractions were the most common arrhythmia, and structural defects were present in four of 58 patients (6.8%) with premature contractions. Fetal heart defects (n = 44) were identified in 40 of 382 (10%) referrals. The defects were complete atrioventricular block (13), ventricular septal defect (4), atrioventricular canal (5), cardiac mass (3), ectopia cordis (2), thoracopagus (2), hypoplastic left ventricle (2), hypoplastic right ventricle (2), atrial flutter (2), pulmonic stenosis (1), single ventricle (2), Uhl's anomaly (1), Ebstein's anomaly (1), mitral atresia (1), d-transposition of the great vessels (1), tetralogy of Fallot with absent pulmonary valve (1), and atrial septal defect and ventricular septal defect (1). There were three false positive (99% specificity) and two false negative (95% sensitivity) fetal echocardiograms. The survival rates for referred patients with heart defects was: live born and perinatal survivor, 54%; perinatal death, 31%; still birth, 11%; and termination of pregnancy, 4%. Fetal echocardiography is accurate, and the abnormalities detected appear to be more severe than those detected on newborn screening.

Aortic arch complex anomalies: 20-year experience with symptoms, diagnosis, associated cardiac defects, and surgical repair.

To better understand the clinical presentation and surgical management of children with aortic arch complex anomalies ("vascular rings"), a retrospective study was performed on patients who presented to Children's National Medical Center between the years 1969 and 1989. A total of 59 patients were identified ranging in age at admission from birth to 14 years, of whom 35 (59%) were male and 24 (41%) female. Patients were classified into four major subtypes based on their surgical anatomy, with 29 (49%) patients having right aortic arch and left ductus/ligamentum arteriosus, 21 (36%) double aortic arch, 6 (10%) anomalous left pulmonary artery, and 3 (5%) arch artery anomaly (no ring); 19 patients (32%) had associated cardiac defects. The mean (+/-SD) age at onset of symptoms was 4.6 +/- 14.0 months, and the age at surgical repair was 18 +/- 34 months. There were no intraoperative mortalities, but two late deaths occurred. Three (5%) patients had a surgical complication. In contrast to previous studies, the incidence of nonring lesions was lower and associated cardiac defects higher. Forty-nine percent of patients had symptoms present at birth, and patients with associated cardiac disease did not present earlier than those without. In patients with right aortic arch and left ductus/ligamentum arteriosus, few had an anomalous left subclavian artery. Finally, equal dominance of the arches was most frequent in patients with double aortic arch. Aortic arch complex anomalies present symptomatically in a variety of ways, and noninvasive methods are used to identify the specific lesion and associated cardiac defects. Surgical repair is associated with low or no mortality in patients with uncomplicated aortic arch complex anomalies.

Atrial septal thickness and area in normal heart specimens and in those with ostium secundum atrial septal defects.

This anatomic study suggests that an understanding of the thickness of the atrial septum should allow better visualization of most portions of the blade-shaped atrial septum during cross-sectional echocardiography, both in normal subjects and in patients with ostium secundum atrial septal defects. The thickness measurements also demonstrate that difficulties in imaging the atrial septum are a function of resolution limits of existing echocardiographic equipment.

Familial occurrence of congenital aneurysm of the muscular interventricular septum.

Congenital aneurysms of the muscular interventricular septum are rare. We report two brothers with this disease and their father, who had marked thinning of part of the muscular interventricular septum with paradoxical motion. These cases lend support to the idea that these aneurysms are the result of an inherited defect in the myocardium.

Two-dimensional echocardiographic evaluation of mitral bioprosthetic function in infants and children.

Two-dimensional echocardiography (2DE) was performed on 13 bioprosthetic mitral valves in 11 pediatric patients, 1 week to 46 months following implantation. Cardiac catheterization confirmed the echocardiographic findings of seven valves. The 11 normally functional bioprosthetic mitral valves by 2DE had leaflet thickness not exceeding 2.0 mm, freely moving leaflets, and normal sewing ring motion. The left atrium (LA) was enlarged only in the presence of mitral valve obstruction, atrial fibrillation, or left ventricular (LV) dysfunction. One bovine valve was stenotic due to fibrous tissue beneath normal valve leaflets; 2DE demonstrated limited leaflet motion, tissue beneath a thin valve leaflet, increase rocking motion of the sewing ring, and LA enlargement. In another patient, a bovine valve produced subaortic LV obstruction due to growth of fibrous tissue outside the stent; 2DE showed that the valve leaflets were thin and moved normally without excessive rocking of the valve ring, and identified the abnormal fibrous tissue in the LV outflow tract.

The effect of graded hypoxia on the embryonic chick heart.

Embryonic ventricular function in the chick was measured in response to graded levels of hypoxia. Myocardial contractility, as measured by cinephotoanalysis and expressed as shortening fraction, was significantly depressed after 1 hour of moderate hypoxia (6% O2) and after 5 hours of milder (16% O2 and 11% O2) levels of hypoxia (P less than .05). Microscopy confirmed associated myocyte damage with cell death noted after 5 hours of moderate hypoxic stress. Heart rate change was not related to the severity of hypoxia. The greatest level of tachycardia was noted with conditions of mildest hypoxia (16% O2). The data confirm that cardiac contractility, as measured by shortening fraction, is depressed on exposure to hypoxia, with impairment of function related to the severity of the hypoxic conditions.

Left ventricular pseudotumor: a two-dimensional echocardiographic sign of aortic insufficiency.

A left ventricular, mass-like echocardiographic density (a pseudotumor), present only during diastole and not attached to any intracardiac structure, was present in 77 of 1,820 consecutive 2-dimensional echocardiograms performed with a rotating-head transducer. Evaluation of the patients with a pseudotumor demonstrated that aortic insufficiency of mild to moderate degree was the most commonly associated lesion. Of the 61 patients with aortic insufficiency in our series, 69% had a left ventricular pseudotumor. Of the cases with a pseudotumor and aortic insufficiency, none had severe aortic insufficiency. Of the 1,759 patients without aortic insufficiency, a left ventricular pseudotumor was present in 2%. In our series, the sensitivity of left ventricular pseudotumor for aortic insufficiency was 69% and the specificity was 98%.

Chronic ethanol exposure in the embryonic chick heart: effect on myocardial function and structure.

To investigate the effect of chronic ethanol exposure on the embryonic chick heart, chick embryos were exposed daily to one of seven graded doses of ethanol or to saline only (shams) from 0 to 96 hr of incubation. One hour before and after exposure at 72 hr, and 1 hr before and after exposure at 96 hr, embryos were analyzed for changes in heart function, embryo tissue ethanol content, occurrence of anomalies, and embryo weights. At both 71 and 73 hr of incubation (during cardiogenesis), when compared to shams, heart rate (HR) in embryos receiving ethanol doses greater than 0.0375 ml increased significantly (P less than .05) with commensurate increases in injected ethanol. Additionally, at 73 hr, depressed cardiac contractility, measured as shortening fraction, was noted at doses greater than or equal to .0375 when compared to shams. While slight increases in shortening fraction (SF) across dose were noted at 95 and 97 hr, only random doses were statistically significant from shams, with no specific trend in either HR or SF at this postcardiogenesis stage. Within each time group, gas chromatography analysis of embryo tissue ethanol content demonstrated a linear relationship between dose injected and tissue ethanol content retrieved. With increasing dose and stage, viability decreased. Weights of ethanol-injected embryos were not significantly different from shams within each time group. Our studies of the response of the embryonic chick heart to ethanol indicate both dose and stage susceptibility, with greater susceptibility to ethanol injury during active cardiogenesis.