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Accessory mitral valve tissue, a rare cause of left ventricular outflow tract obstruction, can be difficult to diagnose preoperatively and confusing even at surgery. The reported case illustrates how preoperative evaluation can be made using two-dimensional echocardiography combined with Doppler flow analysis. The intraoperative technique for removing the accessory tissue without causing damage to the native mitral valve is discussed.

The frequency of chromosomal abnormalities in infants with congenital heart disease has been estimated from postnatal clinic data to be 5% to 10%. Over an 18-month period we performed fetal echocardiograms on 502 fetuses and found cardiac anomalies in 34. Eleven of these fetuses (32%) had abnormal chromosomes. This marked discrepancy from the data found in the pediatric literature may relate to nonviable fetuses identified in utero, who escape pediatric case identification. We conclude that in cases of fetal heart disease the workup should include either amniocentesis or fetal blood sampling for chromosome analysis. The information can be used for complete parental counseling and for managing delivery and neonatal care.

We describe a case of unusual pulmonary vein-to-vein collateral formation leading to systemic desaturation years following surgical repair of a sinus venosus atrial septal defect and partial anomalous pulmonary venous return from the right lung. At surgery, a single right upper lobe pulmonary vein branch was left draining high into the superior vena cava (SVC), resulting in a small left-to-right shunt. SVC obstruction developed at the site of the ASD repair and elevated venous pressure above the obstruction caused retrograde flow into the unincorporated pulmonary vein. Pulmonary vein-to-vein collaterals formed between this unincorporated vein and an adjacent pulmonary vein that had been surgically diverted to drain into the left atrium, resulting in a right-to-left shunt within the right lung. Normal pulmonary veins drain multiple bronchopulmonary segments, thus providing potential collateral pathways. Balloon angioplasty of the SVC stenosis successfully relieved the obstruction and abolished the right-to-left intrapulmonary shunt.

The mechanism of development of hydrops fetalis in severe isoimmunization has been subject to speculation. We performed pulsed Doppler assessment of cardiac output in 13 severely isoimmunized fetuses before and after intravascular transfusion and compared the results with 37 control fetuses between 20 and 34 weeks' gestation. The cardiac index of the anemic fetuses was significantly greater than that of the control group. A significant (right ventricle, p less than 0.01; left ventricle, p less than 0.02) increase in indexed output was noted from both ventricles and in the combined ventricular output (mean +/- SEM 644 +/- 35.3 ml/kg/min in control fetuses versus 879 +/- 86.0 ml/kg/min in anemic fetuses, p less than 0.006). An increase in cardiac output was also noted when anemic fetuses were compared with gestational age-specific norms. We conclude that severely anemic fetuses of isoimmunized pregnancies tend to have significantly higher cardiac output than do unaffected fetuses and that this high output state may play a part in the development of hydrops fetalis.

We admitted 48 preterm neonates (600 to 1250 gm birth weight, normal 6-hour echoencephalograms) to a randomized prospective indomethacin or placebo trial for the prevention of neonatal intraventricular hemorrhage. Beginning at 6 postnatal hours, indomethacin or placebo was administered intravenously every 12 hours for a total of five doses. Cardiac ultrasound studies to assess the status of the ductus arteriosus were performed at 6 postnatal hours and on day 5. Urinary output, serum electrolytes, and renal and clotting functions were monitored. No differences in birth weight, gestational age, Apgar scores, or ventilatory needs were noted between the two groups. Six infants given indomethacin had intraventricular hemorrhage, compared to 14 control infants (P = 0.02). The indomethacin-treated group had significant decreases in serum prostaglandin values 30 hours after the initiation of therapy. The overall incidence of patent ductus arteriosus was 82% at 6 postnatal hours; 84% of the indomethacin-treated infants experienced closure of the ductus, compared to 60% of the placebo-treated patients. Closure of the ductus was not related to incidence of intraventricular hemorrhage. We speculate that indomethacin may provide some protection against neonatal intraventricular hemorrhage by acting on the cerebral microvasculature.

Fetal echocardiograms were performed in 266 gravidae over a one-year period for a variety of previously identified indications. The largest group consisted of 112 patients referred because of other family members with congenital heart disease (CHD). Of these, only one fetus had CHD. The groups with the highest incidence of CHD were those suspected on general obstetrical scan to have structural cardiac disease (50% abnormal) and those scanned after extracardiac anomalies were found (26% abnormals). Forty rhythm abnormalities were encountered, 85% isolated premature atrial extra-systoles. We conclude that fetal echocardiography should be part of the prenatal evaluation of fetuses with extracardiac anomalies and of those with nonimmune hydrops. Any fetus suspected to have an abnormality of cardiac structure from the four-chamber view of the heart usually visualized while obtaining the abdominal circumference should also be evaluated.

Fetal echocardiography has allowed prenatal diagnosis of heart disease to become a reality over the last decade. Recently, pulsed Doppler flow studies have been applied to the examination of the fetal cardiovascular system. In fetuses with dysrhythmias, complex structural heart malformations, nonimmune hydrops fetalis, or mothers receiving nonsteroidal prostaglandin synthetase inhibitors, pulsed Doppler echocardiographic studies are clinically indicated. These studies involve noninvestigational tests that provide information of critical clinical import. These studies may occasionally, require energy intensities that exceed the 510(k) limits. The physician should be held responsible for educating patients to the potential risks versus benefits of any imaging study they undergo, but appending potentially alarming labels to transducers, machines, or cathode-ray tube displays can only serve to undermine the fabric of the physician-patient relationship without achieving the desired goal of protection of the patient.

Fetal tachypnea, defined as more than 60 fetal breaths per minute, has been reported to occur almost always in diabetic pregnancies. We treated a patient for fetal tachypnea and tachycardia, the initial presentation of which led to the diagnosis of diabetes mellitus.

Fetal heart rate monitoring was combined with fetal echocardiography for examination of atrial reactivity during labour in five fetuses with second or third degree heart block. Alterations in vagal tone accompanying uterine contraction influence atrial rate, even when the ventricle is not under atrial 'control'. Fetal echocardiography enabled diagnosis of the underlying basis of the arrhythmia and located the optimal position for recording atrial activity with an external heart rate monitor. External and internal monitoring of atrial activity demonstrated reactivity during labour. Two patients were delivered vaginally after monitoring throughout labour. One mother preferred elective caesarean delivery. Caesarean section was required in another for cephalopelvic disproportion and in the remaining woman for late decelerations. These monitoring techniques provide an assessment of fetal well-being in the presence of fetal bradycardia due to variable degrees of heart block.

Echocardiography may provide information concerning the structural development of the fetal human heart. The information available from such studies, when interpreted in light of existing knowledge of developmental cardiac physiology, may give insight concerning in utero cardiac pump function. The quantitation of cardiac structural growth in utero has been used to provide growth curves for the chambers of the fetal heart. Disparity in the ratio of right ventricular/left ventricular size (normally 1.0 to 1.2) may suggest acute ventricular failure and dilation. Electromechanical analysis using M-mode techniques may be used to analyze and monitor the treatment of fetal cardiac arrhythmias and provide systolic time interval analysis. Doppler waveform analysis provides information concerning directional flow and vascular impedance and Doppler flowmetry has promise for the measurement of fetal aortic and umbilical venous blood flows. Such studies have increased our understanding of fetal circulatory function and have practical implications for the establishment of fetal cardiac diagnosis and treatment programs.

Fetal echocardiography is a well-established technique for the prenatal identification of congenital heart disease. One of the indications for its use is the presence of extracardiac anomalies, as such coexistent defects may have important implications for obstetric and neonatal management. We have reviewed the obstetric and pediatric literature to examine reported associations. If a fetus is suspected to have hydrocephalus, microcephaly, holoprosencephaly, agenesis of the corpus callosum, Meckel-Gruber syndrome, esophageal atresia, duodenal atresia, diaphragmatic hernia, omphalocele, or renal dysplasia, cardiac evaluation should be pursued. Furthermore, echocardiography may be of help in differential diagnosis of some anomalies (for instance, skeletal dysplasias). Maternal diabetes and phenylketonuria, as well as exposure to phenytoin, trimethadione, or isotretinoin, may result in multiple systemic defects, including congenital heart disease.

Serial cranial ultrasound studies, 133xenon inhalation cerebral blood flow determinations, and risk factor analyses were performed in 31 preterm neonates. Contrast echocardiographic studies were additionally performed in 16 of these 31 infants. Sixty-one percent were found to have germinal matrix or intraventricular hemorrhage. Seventy-four percent of all hemorrhages were detected by the thirtieth postnatal hour. The patients were divided into three groups: early GMH/IVH by the sixth postnatal hour (eight infants) interval GMH/IVH from 6 hours through 5 days (10), and no GMH/IVH (12). Cerebral blood flow values at 6 postnatal hours were significantly lower for the early GMH/IVH group than for the no GMH/IVH group (P less than 0.01). Progression of GMH/IVH was observed only in those infants with early hemorrhage, and these infants had a significantly higher incidence of neonatal mortality. Ventriculomegaly as determined by ultrasound studies was noted equally in infants with and without GMH/IVH (50%) and was not found to correlate with low cerebral blood flow. The patients with early hemorrhage were distinguishable by their need for more vigorous resuscitation at the time of birth and significantly higher ventilator settings during the first 36 postnatal hours, during which time they also had higher values of PCO2. An equal incidence of patent ductus arteriosus was found across all of the groups. We propose that early GMH/IVH may be related to perinatal events and that the significant decrease in cerebral blood flow found in infants with early GMH/IVH is secondary to the presence of the hemorrhage itself. Progression of early GMH/IVH and new interval GMH/IVH may be related to later neonatal events known to alter cerebral blood flow.

The antenatal diagnosis of fetal arrhythmias can be a difficult proposition. This paper reports 234 cases of fetal cardiac arrhythmias. One hundred and ninety-four of these were isolated extrasystoles which resolved spontaneously in all except 2 cases. There were 9 patients with complete heart block. Three of these patients had structural anomalies and hydrops. Four other patients with heart block had evidence of maternal collagen disease. Sustained supraventricular tachyarrhythmias are the most common clinical important arrhythmias. Most of these can be successfully controlled with digoxin alone or with verapamil or propranolol. Atrial flutter is more difficult to control than supraventricular tachycardia.

A case of a massive benign intrapericardial teratoma that presented at two weeks of age with significant respiratory distress is described. In retrospect, it was discovered that this infant had been evaluated by fetal echocardiography while in utero at 20 weeks of gestation due to a maternal history of surgically corrected tetralogy of Fallot. The fetal echocardiogram demonstrated normal intracardiac anatomy and no evidence of either a pericardial mass or effusion. It is concluded that this tumor spontaneously enlarged some time between 20 and 40 weeks of gestation.

This report describes a case of corrected transposition of the great arteries (TGA) in which a classic subaortic membrane resulted in significant obstruction to outflow from the morphologically right ventricle. To our knowledge, discrete subaortic obstruction has not been previously reported with corrected TGA.

The four-chamber view of the heart has been proposed as a screening method for obstetrical sonographers to assess the fetus for the presence of congenital heart disease. We examined the fetuses in 1022 pregnancies and found 74 structurally abnormal hearts. Seventy-one of these (96%) were found to have an abnormality as seen in the four-chamber view. The four-chamber view of the heart had 92% sensitivity and 99.7% specificity in the detection of congenital heart disease. The positive predictive value was 95.8%, and the negative predictive value was 99.4%. We conclude that the four-chamber view may be a useful screen for the presence of congenital heart disease and should be included as a part of all routine obstetric ultrasound examinations.

With current ultrasound technology, it is now possible to obtain accurate real-time and M-mode information from the fetal heart with the use of real-time--directed M-mode echocardiography. With this method, the M-mode cursor is directed to the fetal cardiac structures of interest while the image is obtained in the real-time mode. This enables M-mode echocardiograms to be obtained in an accurate, reproducible manner. The most useful imaging planes for cardiac evaluation are the long axis four-chamber plane, the short axis plane through the atrioventricular valves, and the short axis plane through the aortic and pulmonic outflow tracts. Once normal fetal cardiac anatomy is understood, structural defects and/or alterations of function can be evaluated accurately antenatally.

To avoid anticoagulation and minimize thromboembolic phenomena, between 1975 and 1980 we used 18 porcine bioprosthetic valves (BPVs) to replace 11 aortic and seven mitral valves in 17 children ranging from 7 to 18 years of age (mean, 8.2 years). Ten BPVs (91%) in the aortic position had to be replaced one to six years (mean, 4.2 years) after insertion. Nine of these valves developed severe calcification with leaflet immobility and severe stenosis. The tenth valve became insufficient with a disrupted cusp. Six (86%) of seven BPVs inserted in the mitral position required replacement two to four years (mean, 3.1 years) after insertion. Massive mitral regurgitation developed in three, while in the other three mitral stenosis was prominent. All explanted BPVs exhibited calcification with disruption and loss of mobility of the leaflets. Hemodynamic deterioration often occurred catastrophically, with nine patients requiring emergency valve replacement. Elective valve replacement carried no hospital mortality, whereas emergency valve replacement carried a 33% mortality. The BPV failure rate of 94% within six years leads us to recommend against the use of biologic valves in the pediatric age group in the aortic or mitral position. Bioprosthetic valve failure may occur catastrophically and replacement should be carried out early to avoid the higher operative mortality associated with emergency surgery.

During obstetrical ultrasound examinations, 200 M-mode and 35 real-time two-dimensional echocardiographic studies were performed on 180 fetuses of high-risk pregnancies. Fetal gestational ages ranged from 18 to 41 weeks. M-mode "sweeps" demonstrating mitral- and septal-aortic fibrous continuity were obtained in 115 studies. Paradoxic septal motion in 50 fetuses suggested relarive right ventricular volume loading. Congenital cardiac malformations were accurately diagnosed in a 34-week fetus with pulmonary atresia and hypoplastic right ventricle and in a 28-week fetus with a univentricular heart. Congenital complete atrioventricular block was diagnosed in a 28-week fetus and atrial flutter with variable atrioventricular block was diagnosed in a 38-week fetus. The use of echocardiographic studies to evaluate cardiac structure and rhythm in utero assists in counseling prospective parents and in planning postnatal management for their offspring.

Complete interatrial block with two independent atrial rhythms is demonstrated by intracardiac electrograms in a patient with transposition of the great arteries who had undergone a Mustard operation. The atrial conduction abnormalities produced by the Mustard procedure with subsequent baffle revision are related to damaged anatomic interatrial connections and are similar to conduction abnormalities produced in experimental models of interatrial block.

The electrocardiographic, hemodynamic and surgical data of 30 patients who underwent a Fontan operation between 1977 and 1986 were retrospectively reviewed to identify the incidence and predictors of immediate and late postoperative arrhythmias and associated morbidity in long-term survivors. Of 4 patients who died less than 1 year after operation (mortality 13%), 1 death was related to an arrhythmia. Three patients were not in sinus rhythm before operation and were excluded from the statistical analysis that examined predictors of arrhythmias. The remaining 23 long-term survivors have been followed 6.3 +/- 2.6 years (mean +/- standard deviation) since surgery and all remain in New York Heart Association functional class I or II. Ten patients (43%) developed immediate postoperative arrhythmias (less than or equal to 30 days) whereas 11 (48%) had late arrhythmias. With up to 10.7 years of follow-up, the proportion of patients free from late arrhythmias continues to decline. Arrhythmias included bradyarrhythmias, atrial tachyarrhythmias, the tachy-brady syndrome and supraventricular ectopic activity. Immediate postoperative arrhythmias predicted late arrhythmias (p = 0.022). The preoperative electrocardiogram was the only variable useful in predicting both immediate and late postoperative arrhythmias. A more negative P-wave deflection in lead V1 (-2.4 +/- 0.7 vs -1.4 +/- 1.2 mV, p = 0.02) predicted patients with immediate postoperative arrhythmias, whereas both greater P-wave duration and a more negative deflection in this lead predicted late arrhythmias (103 +/- 14 vs 83 +/- 20 ms, p = 0.01, and -2.5 +/- 0.8 vs -1.3 +/- 1.0 mV, p = 0.005, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

From 1978 to 1987, 350 infants and children had silicone central catheters placed for long-term venous access. Real time echocardiography showed a catheter tip thrombus in 16 patients, including 12 premature infants and four children. Catheters had been in place for eight to 560 days. Thirteen patients were receiving total parenteral nutrition (TPN) at the time thrombus was identified, and one patient had received TPN 2 weeks previously. Indications for echocardiography included sepsis (7), respiratory insufficiency (6), evaluation of heart disease (3), and catheter malfunction (1); several patients had multiple indications. Treatment was individualized and included atriotomy (2), systemic heparin and thrombolytic agents with or without catheter removal (8), catheter removal only (3), and observation (3). Four of eight patients treated with thrombolysis had complete clot lysis and four had partial dissolution. Two patients managed expectantly had resolution of the thrombus. None of the patients suffered further complications or died as a result of the thrombus, but ten of the 16 died 1 to 12 weeks later from their underlying disease. Forty-seven asymptomatic patients were studied by echocardiography to assess the incidence of unsuspected right atrial thrombus. Their catheters had been in place for a mean of 200 days and only 11 had been used for TPN. None of these patients had identifiable thrombus at the catheter tip. The incidence of catheter tip thrombus, which is higher than previously suspected, is related to prematurity, TPN, and continuous catheter use, but not duration of catheterization. The incidence is low in asymptomatic patients. Treatment regimen must be individualized and this series reflects a trend toward more conservative management.