Fetal cardiac dextroposition in the absence of an intrathoracic mass: sign of significant right lung hypoplasia

We reviewed our experience of fetal cardiac dextroposition in the absence of an intrathoracic mass. Ten cases were found by fetal echocardiography to have a normal cardiac axis, but the heart was shifted into the right chest and the amount of right lung tissue was reduced. At birth seven of the infants had confirmed structural heart disease (70%), including three with scimitar syndrome. Two infants had additional extracardiac anomalies (20%). Seven infants born at term had clinical pulmonary hypertension with a diagnosis of right lung hypoplasia in all of them. Two neonates died owing to significant heart disease (one with scimitar syndrome and the other with hypoplastic left heart syndrome). Of the three pregnancies that were terminated, the two fetuses with autopsies had severe right lung hypoplasia. Fetal cardiac dextroposition and right pulmonary artery hypoplasia in the absence of an intrathoracic mass are important signs of right lung hypoplasia, which can be associated with significant pathologic cardiac and extracardiac conditions.

Echocardiographic identification of thymic hypoplasia in tetralogy of fallot/tetralogy pulmonary atresia

The use of transthoracic echocardiography to detect the presence of thymic tissue has been reported in patients at risk for graft versus host disease. We confirmed the accuracy of this method in patients with tetralogy of Fallot and tetralogy of Fallot/pulmonary atresia, and suggest using a threshold distance of 6.1 cm/m2 (5.5 to 6.3 cm/m2).

Echocardiographic assessment of interrupted aortic arch

BACKGROUND

In patients with interrupted aortic arch echocardiography provides detailed information about the anatomy of the aortic arch and the associated cardiac anomalies. Only a few reports have evaluated the reliability of this non-invasive diagnostic procedure by correlation with angiographic and surgical findings.

METHODS

From 1988 through 1993, 45 infants with interrupted arch underwent surgical repair (mean age 13.02 days). Of the patients, 33 had interruption of the arch between the left common carotid and subclavian arteries; 25 patients had a ventricular septal defect, and the remaining 20 had coexisting complex congenital heart defects. Preoperative diagnosis was made exclusively by echocardiography in 25 of the patients. Accuracy of echocardiographic diagnosis was evaluated retrospectively by comparing preoperative studies with angiography and surgical reports. We then investigated whether the morphologic features of the interrupted arch might influence surgical procedure or outcome.

RESULTS

Intracardiac anatomy was accurately diagnosed by echocardiography in all cases; in 2 patients angiography provided additional information concerning the morphology of the aortic arch. Operative notes described differences in morphology of the arch in 7 patients, but these did not influence the surgical procedure. Direct anastomosis of the interrupted segments was possible in 38 patients, and 36 patients underwent primary intracardiac repair. Echocardiographic measurements revealed that the diameter of the ascending aorta was related to the number of vessels originating from the proximal aortic arch. The distance between the interrupted segments was significantly different according to the site of interruption, but not between cases with an isolated ventricular septal defect versus those with complex heart disease. It did not influence the method of arch repair, nor was it related to recurrent or residual obstruction.

CONCLUSION

Preoperative echocardiography offers accurate and complete diagnosis in the critically ill neonate with interrupted aortic arch and associated intracardiac abnormalities.

Prenatal features of ductus arteriosus constriction and restrictive foramen ovale in d-transposition of the great arteries

BACKGROUND

Although most neonates with d-transposition of the great arteries (TGA) have an uncomplicated preoperative course, some with a restrictive foramen ovale (FO), ductus arteriosus (DA) constriction, or pulmonary hypertension may be severely hypoxemic and even die shortly after birth. Our goal was to determine whether prenatal echocardiography can identify these high-risk fetuses with TGA.

METHODS AND RESULTS

We reviewed the prenatal and postnatal echocardiograms and outcomes of 16 fetuses with TGA/intact ventricular septum or small ventricular septal defect. Of the 16 fetuses, 6 prenatally had an abnormal FO (fixed position, flat, and/or redundant septum primum). Five of the 6 had restrictive FO at birth. Five fetuses had DA narrowing at the pulmonary artery end in utero, and 6 had a small DA (diameter z score of <-2.0). Of 4 fetuses with the most diminutive DA, 2 also had an abnormal appearance of the FO, and both died immediately after birth. One other fetus had persistent pulmonary hypertension. Eight fetuses had abnormal Doppler flow pattern in the DA (continuous high-velocity flow, n=1; retrograde diastolic flow, n=7).

CONCLUSIONS

Abnormal features of the FO, DA, or both are present in fetuses with TGA at high risk for postnatal hypoxemia. These features may result from the abnormal intrauterine hemodynamics in TGA. A combination of restrictive FO and DA constriction in TGA may be associated with early neonatal death.

Adams-Oliver syndrome associated with cardiovascular malformations

We describe two families with Adams-Oliver syndrome (AOS), an autosomal dominant malformation syndrome (MIM No. 10030), in which cardiovascular malformations (CVMs) have been reported previously. In the first family, twin boys and their mother had the typical digital and scalp defects of AOS with various obstructive CVMs of the left heart (bicuspid aortic valve, Shone's complex). At least three other relatives not examined personally are reported to have related CVMs (aortic valve stenosis, hypoplastic left heart syndrome). In the second family, a girl had typical AOS digital and scalp defects and a bicuspid aortic valve. At least three other relatives are reported to be mildly affected. Tetralogy of Fallot had been previously reported as the most common CVM in AOS [Zapata HH, Sletten LJ, Pierport MEM (1995). J Med Genet 47:80-84.]. However, with the addition of these new patients and two other literature reports, we emphasize that approximately 20% have a CVM, frequently obstructive lesions of the left heart. Cardiology consultation should be offered to most patients with AOS.

Mitral and aortic atresia associated with hypoplastic right lung, crossover segment of right lower lobe, and anomalous scimitar-like right pulmonary venous connection with inferior vena cava: clinical, angiocardiographic, and autopsy findings in a rare case

A newborn female infant was found to have a unique and previously unreported group of anomalies: (1) mitral and aortic atresia with a highly obstructive atrial septum; (2) hypoplasia of the right lung with a crossover segment involving the right lower lobe; (3) normally connected pulmonary veins, two from the left lung and one from the right; and (4) a large anomalous branch of the right pulmonary vein of scimitar configuration that anastomosed with the normally connected right pulmonary vein and with the inferior vena cava (IVC). The scimitar vein appeared obstructed at its junction with the right pulmonary vein and at its junction with the inferior vena cava within the hepatic parenchyma. To our knowledge, this is the first report of a scimitar-like vein coexisting with mitral and aortic atresia and connecting both with the right pulmonary vein and with the inferior vena cava. The highly obstructed left atrium was partially decompressed by retrograde blood flow via the normally connected right pulmonary vein to the anomalous scimitar venous pathway and thence to the inferior vena cava via a pulmonary-to-IVC collateral vein.

Utility of intraoperative transesophageal echocardiography in the assessment of residual cardiac defects

To investigate the accuracy of immediate postbypass transesophageal echocardiography in the assessment of residual cardiac defects, we compared intraoperative transesophageal echocardiograms with intra/postoperative data in 86 patients, aged 4 days to 30.7 years (median = 1.4 years), at risk for a total of 174 postoperative lesions: right (n = 55) or left (n = 26) ventricular outflow tract obstruction, ventricular septal defect (n = 65), aortic (n = 12) or mitral regurgitation (n = 8), or mitral stenosis (n = 8). Accuracy of intraoperative transesophageal echocardiography was evaluated based on comparison with (1) immediate post-bypass left (n = 4) or right (n = 9) ventricular outflow tract pressure gradients by pullback in the operating room, (2) direct surgical inspection of residual ventricular septal defects (n = 3), (3) pulmonary artery oxygen saturation (n = 49), (4) right ventricular outflow tract pullback gradient (n = 24), and (5) transthoracic echocardiogram (n = 51) performed within 40 days of surgery. The results indicate that intraoperative transesophageal echocardiography agreed with intra/postoperative data in 87% of patients at risk for right ventricular outflow tract obstruction, 96% at risk for left ventricular outflow tract obstruction, 97% at risk for ventricular septal defect, and 100% at risk for aortic regurgitation, mitral regurgitation, or mitral stenosis. Significant residual lesions led to immediate surgical revision in 11 cases: 3 ventricular septal defects, 6 right and 2 left ventricular outflow tract obstructions. Of these, intraoperative transesophageal echocardiography confirmed and quantified suspected residual lesions in 7 and identified unsuspected lesions in 4 cases. Immediate postbypass transesophageal echocardiography proved reliable for assessing residual ventricular septal defect, mitral stenosis, and mitral or aortic regurgitation. Although accurate for assessment of the left and right ventricular outflow tracts in most patients, transesophageal echocardiography may not reliably reflect the severity of obstruction in all cases.

Sevoflurane depresses myocardial contractility less than halothane during induction of anesthesia in children

BACKGROUND

Cardiovascular stability is an important prerequisite for any new volatile anesthetic. We compared echocardiographically derived indices of myocardial contractility during inhalation induction with sevoflurane and halothane in children.

METHODS

Twenty children were randomized to receive either halothane or sevoflurane for inhalation induction of anesthesia. No preoperative medications were given. Myocardial contractility was evaluated at baseline and at sevoflurane and halothane end-tidal concentrations of 1.0 minimum alveolar concentration (MAC) and 1.5 MAC.

RESULTS

There were no differences between groups in patient age, sex, physical status, weight, or height. Equilibration times and MAC multiples of sevoflurane and halothane were comparable. Vital signs remained stable throughout the study. Left ventricular end-systolic meridional wall stress increased with halothane but remained unchanged with sevoflurane. Systemic vascular resistance decreased from baseline to 1 MAC and 1.5 MAC with sevoflurane. Halothane depressed contractility as assessed by the stress-velocity index and stress-shortening index, whereas contractility remained within normal limits with sevoflurane. Total minute stress and normalized total mechanical energy expenditure, measures of myocardial oxygen consumption, did not change with either agent.

CONCLUSIONS

Myocardial contractility was decreased less during inhalation induction of anesthesia with sevoflurane compared with halothane in children. Although the induction of anesthesia with sevoflurane or halothane was equally well tolerated, the preservation of myocardial contractility with sevoflurane makes it an attractive alternative for inducing anesthesia in children.

Echocardiographic predictors of candidacy for successful transcatheter atrial septal defect closure

We reviewed pre-closure echocardiograms on all patients undergoing transcatheter atrial septal defect (ASD) closure with the Bard double-umbrella occluder device aided by simultaneous transesophageal echocardiography to determine precatheterization predictors of outcome. Transesophageal echocardiograms were performed on 28 of 132 patients (22%) undergoing device closure (age = 3-72 years, mean = 14 years; weight = 15-68 kg, mean = 35 kg). Three devices were removed because of unstable position. Of the remaining 25 patients, 21 had effective closure (residual flow diameter < or = 3 mm) and 18 had favorable arm position (device arm on proper side of the septum and not in contact with an atrioventricular valve leaflet). Only ASD size predicted effective closure. All patients with a maximum defect size of < 13 mm had effective closure. Among the 17 patients with defects > or = 13 mm, 10 had effective closure, 4 had significant residual flow, and 3 had devices removed for unstable position. Atrial dimensions and rim size did not predict effective closure. There were no pre-closure predictors of favorable arm position which was associated only with the size of the device implanted.

Pediatric biplane transesophageal echocardiography: preliminary experience

Recent development of prototype pediatric biplane transducers has extended the use of biplane TEE imaging to the neonate. One such TEE probe with 64 imaging elements in each pallet was used perioperatively in 46 infants and children (weight 2.9 to 32 kg) undergoing surgery for complex congenital heart disease. The success rate for passing the transducer, complications of the procedure, and the number of cases in which the vertical plane provided information that was not available from the horizontal plane were determined. Probe insertion was successful in all patients. Imaging was discontinued in one neonate because of possible airway compression by the probe. Image quality was excellent in the other 45 patients. The vertical plane added information over that obtained from the horizontal plane in 58 (44%) of the 132 anomalies identified. The addition of the vertical plane was especially useful in imaging abnormalities of the ventricular outflow tracts.

Transesophageal echocardiographic guidance of transcatheter ventricular septal defect closure

OBJECTIVES

This report describes transesophageal echocardiographic guidance of transcatheter closure of ventricular septal defects and its value as an adjunct to fluoroscopy and angiography in this procedure.

BACKGROUND

Experience with transcatheter closure of ventricular septal defects has identified a diverse group of patients in whom it may be the procedure of choice. Although facilitating other interventional procedures, such as transcatheter closure of atrial septal defects, the value of transesophageal echocardiographic guidance for transcatheter ventricular septal defect closure has not been documented.

METHODS

All patients who underwent ventricular septal defect closure with transesophageal echocardiographic guidance before November 1992 were included. Angiograms and echocardiograms were reviewed to evaluate device position and relation to valve tissue during placement and to assess residual flow after device implantation. The ability of transesophageal echocardiography to assess these variables was compared with fluoroscopy and angiography.

RESULTS

Transesophageal echocardiographic guidance was used in 31 of the 83 catheterizations involving transcatheter ventricular septal defect closure performed between February 1990 and November 1992. Under transesophageal echocardiographic guidance, 45 devices were implanted: 23 in muscular ventricular septal defects, 17 in residual postoperative patch margin defects and 5 in other ventricular septal defects. Transesophageal echocardiographic guidance enhanced assessment of device position and proximity to valve structures and markedly improved assessment of residual flow. Assessment of residual flow with transesophageal echocardiography eliminated the need for multiple angiograms in some patients. Combining transesophageal echocardiography with fluoroscopy and angiography provided the most information.

CONCLUSIONS

Transesophageal echocardiography facilitates transcatheter closure of ventricular septal defects by improving assessment of device position and effectiveness of closure. It is indicated when device placement is likely to be difficult or may interfere with valve structures or when multiple interventional procedures are anticipated.

"Intramural" residual interventricular defects after repair of conotruncal malformations

BACKGROUND

We report an unusual type of residual interventricular communication in patients with conotruncal malformations in which the aorta is completely or partly aligned with the right ventricle (RV). Interventricular communications after surgical repair usually result from additional defects, patch dehiscence, or incomplete closure and lie in the septal plane. However, after a right ventricular aorta is baffled to the left ventricle, the ventricular septal defect (VSD) patch and RV free wall form part of the systemic outflow tract. This "neo-left ventricular" outflow tract may provide a location for residual interventricular communications out of the septal plane.

METHODS AND RESULTS

We reviewed echocardiographic, angiographic, and clinical records of patients who had one or more residual interventricular communications out of the plane of the ventricular septum after repair of a conotruncal anomaly. Between June 1990 and October 1992, we observed such defects in eight patients, 5 to 26 years old, after repair of double-outlet right ventricle (n = 6), tetralogy of Fallot (n = 1), or truncus arteriosus (n = 1). In each, the VSD patch was anchored to the RV free wall near the aortic root. Nonetheless, channels were observed around the edge of the patch, between the neo-systemic outflow tract and the right ventricle. All patients had right ventricular hypertension; in seven, the pulmonary-to-systemic flow ratio (Qp:Qs) was > or = 2. At multiple unsuccessful reoperations (two to four per patient), the patch edges appeared securely attached to myocardium. Angiographic views profiling the septum failed to localize these defects, since they are not in the native septum. Echocardiographic detection of such anterior defects can be difficult. Transcatheter umbrella closure was attempted in the seven patients with large shunts; success was limited by the multiplicity of flow channels. Umbrella closure eliminated the need for further reoperation in four of seven patients, one patient died suddenly awaiting reoperation, and two deaths followed reoperation.

CONCLUSIONS

"Intramural" residual interventricular defects are difficult to diagnose by all modalities. Umbrella placement may reduce the left-to-right shunt. Successful surgical closure may require removal and reattachment of the anterior portion of the patch.

Transcatheter closure of atrial and ventricular septal defects

The clamshell double umbrella (Bard Clamshell Septal Umbrella, USCI Division, C. R. Bard, Billerica, MA) was developed to allow closure of septal defects, both atrial and ventricular. The device and delivery system and the techniques for implanting the device in atrial and ventricular defects are described in detail. Although fractures of the arms supporting the umbrellas in some patients have lead to modification of the device, the early experience in clinical trails are encouraging.

Diagnosis of anomalous left coronary artery by Doppler color flow mapping: distinction from other causes of dilated cardiomyopathy

BACKGROUND

Anomalous origin of the left coronary artery from the pulmonary trunk is difficult to diagnose reliably by two-dimensional echocardiography. Therefore, Doppler color flow mapping was tested in 29 patients with dilated cardiomyopathy or anomalous left coronary artery, or both.

METHODS AND RESULTS

All patients with anomalous left coronary artery (10 patients) or dilated cardiomyopathy (27 patients) (excluding those with other known causes for cardiomyopathy) examined between January 1988 and May 1991 were identified. The direction of flow in the three main segments of the left coronary system was determined by Doppler color flow mapping. In all 10 patients with anomalous left coronary artery, flow mapping demonstrated an abnormal jet from the left coronary artery into the pulmonary trunk and retrograde flow in at least two segments of the left coronary system. The diagnosis was confirmed in all 10 patients at operation. Doppler color flow mapping, performed in 19 of the 27 patients with dilated cardiomyopathy, demonstrated anterograde flow in at least one segment of the left coronary system in 16 of the 19 patients; flow direction was not determined in the other 3 patients. Coronary artery anatomy was confirmed by aortic root or left ventricular angiography in 14 patients and at autopsy in 1 patient and was not directly confirmed in 4 patients. Left ventricular function spontaneously improved to normal in three of the latter four patients, a clinical course not consistent with anomalous left coronary artery. The left coronary artery appeared to arise from the aortic root by two-dimensional echocardiographic imaging alone in all patients with dilated cardiomyopathy and in 5 of 10 patients with anomalous left coronary artery (50% false negative diagnoses).

CONCLUSIONS

Detection of an abnormal jet into the pulmonary trunk and retrograde flow in the left coronary system by Doppler color flow mapping is reliable for diagnosing anomalous left coronary artery whereas two-dimensional echocardiographic imaging alone is often inconclusive or misleading. Determining flow direction in the left coronary system in patients with dilated cardiomyopathy is useful for excluding anomalous left coronary artery but is technically more difficult to document in this condition than in anomalous left coronary artery.

Two-dimensional echocardiography in the pre- and postoperative management of totally anomalous pulmonary venous connection

The records of 23 infants who underwent surgical repair of isolated totally anomalous pulmonary venous connection were reviewed to assess the accuracy of pre- and postoperative echocardiographic diagnoses. Preoperative echocardiographic diagnoses were accurate in 22 of 23 patients, including the sites of connection of the individual pulmonary veins. Cardiac catheterization in 13 patients confirmed the echocardiographic findings. Analysis of multiple pre- and postoperative variables revealed no statistically significant difference between the infants with and without catheterization, although there was a tendency toward a higher mortality rate in the catheterized group. Postoperative echocardiographic examination revealed obstruction to pulmonary venous return in 7 of 19 patients. Catheterization confirmed the echocardiographic findings, localizing the obstruction in one patient. The size of the venoatrial anastomosis was measured on postoperative echocardiograms performed on 14 patients. The cross-sectional area of the anastomosis was less than 0.3 cm2/m2 of body surface area in the four patients with obstruction of the anastomosis, and greater than 0.95 cm2/m2 in all long-term survivors examined. Two-dimensional echocardiography with pulsed Doppler examination and Doppler color flow mapping is an excellent means of diagnosing totally anomalous pulmonary venous connection. The connections of the individual pulmonary veins can be identified in nearly all cases. Surgical repair can usually be undertaken on the basis of echocardiographic diagnosis alone. Echocardiography also provides an extremely accurate method of evaluating surgical repair and of identifying and localizing postoperative obstruction to pulmonary venous return.

Transesophageal echocardiography with color Doppler during interventional catheterization

Echocardiography has been used during interventional cardiac catheterization for guidance of the procedure and assessment of results. However, limited echocardiographic windows and logistical difficulties make conventional echocardiography during interventional catheterization impractical and of limited value. Transesophageal echocardiography (TEE) with Doppler color flow mapping is more useful than conventional echocardiography for guidance of interventional catheterizations. Device closure of congenital atrial and ventricular septal defects (ASDs and VSDs) and of postoperative residual interatrial and interventricular communications, balloon valvuloplasty, and Brockenbrough atrial septal puncture with ASD creation have been performed under combined fluoroscopic and TEE guidance. Transesophageal echocardiography can be performed continuously throughout the procedure, allowing simultaneous fluoroscopic and echocardiographic assessment of catheter position. Localization of individual device arms during transcatheter device closure of ASDs and VSDs is easier and more accurate when TEE is used, resulting in a lower incidence of incorrect device positioning. Doppler color flow mapping is used to determine number, location, and size of defects, to detect residual shunts after device closure, and to assess valve insufficiency after balloon valvuloplasty and other procedures. Combined TEE and fluoroscopic guidance of interventional procedures, with echocardiographic assessment of results, reduces the amount of radiation and contrast used during the procedure, allowing performance of additional interventional procedures during the same catheterization. Transesophageal echocardiography is indicated during interventional procedures in which simultaneous Doppler color flow mapping and precise localization of catheter, balloon and/or device position will result in a higher success rate and decreased morbidity.