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PubMed1994

Three-dimensional reconstruction of ventricular septal defects: validation studies and in vivo feasibility.

OBJECTIVES: The purpose of this study was to demonstrate the feasibility of in vivo three-dimensional reconstruction of ventricular septal defects and to validate its quantitative accuracy for defect localization in excised hearts (used to permit comparison of three-dimensional and direct measurements without cardiac contraction). BACKGROUND: Appreciating the three-dimensional spatial relations of ventricular septal defects could be useful in planning surgical and catheter approaches. Currently, however, echocardiography provides only two-dimensional views, requiring mental integration. A recently developed system automatically combines two-dimensional echocardiographic images with their spatial locations to produce a three-dimensional construct. METHODS: Surgically created ventricular septal defects of varying size and location were imaged and reconstructed, along with the left and right ventricles, in the beating heart of six dogs to demonstrate the in vivo feasibility of producing a coherent image of the defect that portrays its relation to surrounding structures. Two additional gel-filled excised hearts with defects were completely reconstructed. Quantitative localization of the defects relative to other structures (ventricular apexes and valve insertions) was then validated for seven defects in excised hearts. The right septal margins of the exposed defects were also traced and compared with their reconstructed areas and circumferences. RESULTS: The three-dimensional images provided coherent images and correct spatial appreciation of the defects (two inlet, two trabecular, one outlet and one membranous Gerbode in vivo; one inlet and one apical in excised hearts). The distances between defects and other structures in the excised hearts agreed well with direct measures (y = 1.05x-0.18, r = 0.98, SEE = 0.30 cm), as did reconstructed areas (y = 1.0x-0.23, r = 0.98, SEE = 0.21 cm2) and circumferences (y = 0.97x + 0.13, r = 0.97, SEE = 0.3 cm). CONCLUSIONS: Three-dimensional reconstruction of ventricular septal defects can be achieved in the beating heart and provides an accurate appreciation of defect size and location that could be of value in planning interventions.

Animals↗
PubMedDate not supplied

Comparison of intraoperative transesophageal echocardiography to epicardial imaging in children undergoing ventricular septal defect repair.

Intraoperative transesophageal echocardiography was compared with epicardial echocardiography after ventricular septal defect repair. This comparison was made in 18 children aged 7 to 137 months (median, 32 months), weighing 6.3 to 49.1 kg (median, 10.8 kg) from November 1989 to January 1991. Ventricular septal defect types were perimembranous (six), malalignment (seven), supracristal (three), midmuscular (one), and inlet (one). Eight children had isolated ventricular septal defects, four had tetralogy of Fallot, three had double outlet right ventricle, two had double chambered right ventricle, and one had pulmonary stenosis. Patch interrogation was complete in 17 of 18 transesophageal echocardiography and 16 of 18 epicardial echocardiography studies. Inability to fully interrogate the ventricular septal defect patch by epicardial echocardiography occurred in two children as a result of anterior ventricular septal defect location, limited epicardial exposure, and surgical hardware interference. Incomplete transesophageal echocardiography patch interrogation occurred in the child with the midmuscular ventricular septal defect. Seven residual ventricular septal defects were documented by color flow Doppler in six patients. Five of seven residual defects were demonstrated by both real-time transesophageal echocardiography and epicardial echocardiography imaging. Transesophageal echocardiography and epicardial echocardiography missed 1 and 7 defects, respectively. The missed defects were different with each technique and were confirmed by postoperative surface echocardiography. No residual defects of sufficient size to require reoperation were found as determined by combination color flow jet analysis and intraoperative oximetry (no pulmonary to systemic flow ratio was greater than 1.50). Patches caused two-dimensional and Doppler signal masking, but this was not limiting because all residual defects were found at the margins of the ventricular septal defect patch.(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗
PubMed1998

Spontaneous closure of muscular ventricular septal defect identified by echocardiography in neonates.

Muscular ventricular septal defects were diagnosed by echocardiography in 97 neonates within 7 days of birth. In 82 of the neonates (84.5%), the defect was solitary, while 15 had multiple defects. The solitary defects was located at mid-septal, apical, anterior and inlet locations in 42 (51.2%), 21 (25.6%), 14 (17.1%) and 5 (6.1%) neonates, respectively. Multiple defects occurred in the apical, anterior and mid-septal areas. The diameter of the solitary defects ranged from 1 to 6 mm (2.3 +/- 0.8 mm), while the multiple lesions were 1 to 4 mm in diameter (2.1 +/- 0.8 mm) in 28 instances in which they could measured. It proved possible to follow 79 of the patients for period of 10 to 13 months. The defects closed spontaneously in 56 (84.8%) of 66 patients with a single defect, and in 7 (53.8%) of 13 of those with multiple defects (P<0.05). For the solitary defects, the position and size were factors determining the likelihood and speed of closure. Defects located at the apical septum, or defects larger than 4 mm in diameter, closed slowly and at a later stage. Echocardiography is an useful technique in establishing of natural history of muscular ventricular septal defects encountered in neonates.

Echocardiography, Doppler↗
PubMed2004

Descriptive epidemiology of selected congenital heart defects, Hawaii, 1986-1999.

Congenital heart defects are the most common type of birth defect and contribute the most to infant mortality due to birth defects. This study examined the relationship between several demographic factors and selected congenital heart defects among the unique multiethnic population in Hawaii during 1986-99, using data from a population-based birth defects registry. Rates were significantly higher in 1993-99 than in 1986-92 for transposition of the great arteries and Ebstein's anomaly, and significantly lower for tetralogy of Fallot. Significantly elevated rates were found with maternal age of > or =35 years for ventricular septal defect, atrial septal defect, endocardial cushion defect, and hypoplastic left heart syndrome. When cases with a known chromosomal abnormality were excluded, elevated rates among the older maternal age group remained for ventricular septal defect, atrial septal defect, and hypoplastic left heart syndrome. Whites had significantly higher rates than one or more of the other racial/ethnic groups for Ebstein's anomaly and coarctation of aorta, and significantly lower rates for tetralogy of Fallot, atrial septal defect, pulmonary valve atresia/stenosis, tricuspid valve atresia/stenosis, and anomalous pulmonary venous return. Significantly higher rates were found among males for transposition of great arteries, aortic valve stenosis, and interrupted aortic arch and, among females, for ventricular septal defect, endocardial cushion defect, and anomalous pulmonary venous return. Some of these differences were consistent with the literature while others were not.

Adult↗
PubMed1993

Complementation of a poliovirus defective genome by a recombinant vaccinia virus which provides poliovirus P1 capsid precursor in trans.

Defective interfering (DI) RNA genomes of poliovirus which contain in-frame deletions in the P1 capsid protein-encoding region have been described. DI genomes are capable of replication and can be encapsidated by capsid proteins provided in trans from wild-type poliovirus. In this report, we demonstrate that a previously described poliovirus DI genome (K. Hagino-Yamagishi and A. Nomoto, J. Virol. 63:5386-5392, 1989) can be complemented by a recombinant vaccinia virus, VVP1 (D. C. Ansardi, D. C. Porter, and C. D. Morrow, J. Virol. 65:2088-2092, 1991), which expresses the poliovirus capsid precursor polyprotein, P1. Stocks of defective polioviruses were generated by transfecting in vitro-transcribed defective genome RNA derived from plasmid pSM1(T7)1 into HeLa cells infected with VVP1 and were maintained by serial passage in the presence of VVP1. Encapsidation of the defective poliovirus genome was demonstrated by characterizing poliovirus-specific protein expression in cells infected with preparations of defective poliovirus and by Northern (RNA) blot analysis of poliovirus-specific RNA incorporated into defective poliovirus particles. Cells infected with preparations of defective poliovirus expressed poliovirus protein 3CD but did not express capsid proteins derived from a full-length P1 precursor. Poliovirus-specific RNA encapsidated in viral particles generated in cells coinfected with VVP1 and defective poliovirus migrated slightly faster on formaldehyde-agarose gels than wild-type poliovirus RNA, demonstrating maintenance of the genomic deletion. By metabolic radiolabeling with [35S]methionine-cysteine, the defective poliovirus particles were shown to contain appropriate mature-virion proteins. This is the first report of the generation of a pure population of defective polioviruses free of contaminating wild-type poliovirus. We demonstrate the use of this recombinant vaccinia virus-defective poliovirus genome complementation system for studying the effects of a defined mutation in the P1 capsid precursor on virus assembly. Following removal of residual VVP1 from defective poliovirus preparations, processing and assembly of poliovirus capsid proteins derived from a nonmyristylated P1 precursor expressed by a recombinant vaccinia virus, VVP1 myr- (D. C. Ansardi, D. C. Porter, and C. D. Morrow, J. Virol. 66:4556-4563, 1992), in cells coinfected with defective poliovirus were analyzed. Capsid proteins generated from nonmyristylated P1 did not assemble detectable levels of mature virions but did assemble, at low levels, into empty capsids.(ABSTRACT TRUNCATED AT 400 WORDS)

Capsid↗
PubMed1977

Natural history of the ventricular septal defect in tricuspid atresia and its surgical implications.

We have previously reported isolated cases of anatomical and functional closure of ventricular septal defects in tricuspid atresia. To study this phenomenon further, clinical, angiographic, and pathological findings in 20 consecutive cases of tricuspid atresia were reviewed. Sixteen cases were found to have normally related great arteries (type I) and 4 had transposition (type II). In 6 of these patients there was evidence of closure of a ventricular septal defect; in 3 this was complete and in the other 3, partial. Five of these ventricular septal defect closures occurred in type I patients and one among type II. Increasing cyanosis and polycythaemia and/or disappearance of a previously heard murmur were observed in all patients; these signs are more conspicuous in complete closure than in partial. The incidence of closure of ventricular septal defect in tricuspid atresia is 38 per cent and approximates to the incidence of spontaneous closure of isolated ventricular septal defects. Progressive muscular "encroachment" of the margins of ventricular septal defects with subsequent fibrosis and covering by endocardial proliferation is the most likely mechanism of closure in tricuspid atresia. The factors initiating the closure of ventricular septal defect remain unknown, but because of its occurrence in patients both with and without previous shunt operations, it is reasonable to assume that closure of ventricular septal defect in tricuspid atresia is not initiated or accelerated by these surgical shunts. Recent developments in surgical technique permit total surgical correction of tricuspid atresia at least in a physiological sense, but these operations can be successfully performed only in older children (over 8 years). Thus, palliation is essential in younger patients until they reach the age for total correction. A Blalock-Taussig shunt is recommended in preference to a Glenn anastomosis because the latter may leave the left pulmonary circuit without blood supply if the ventricular septal defect closes. In type II cases, a large and non-restrictive ventricular septal defect is essential for survival of the patient after the Fontan operation. For this reason, the size of the ventricular septal defect should be evaluated before and at the time of surgical correction. If the ventricular septal defect is small in a type II case, resection of the ventricular septum or a complete bypass of the ventricular septal defect and right ventricle is necessary at the time of the Fontan operation.

Adolescent↗
PubMed1985

Functional and anatomical correlates in atrial septal defect. An echocardiographic analysis.

The results of cross sectional echocardiography, intracardiac contrast echocardiography, and balloon sizing techniques and conventional haemodynamic assessment were correlated in 40 consecutive patients evaluated for an isolated left to right shunt at atrial level. Echo free areas along the septum were identified in 23 of 25 patients with a secundum defect, but not in two with a fenestrated defect, and in the upper atrial septum in three of four patients with a sinus venosus defect. No false positive results occurred in 11 patients with a probe patent foramen ovale. Saline contrast injection into the left atrium showed significant left to right shunting in all patients with atrial septal defect; inferior vena caval injection produced right to left shunting in 15 of 29 patients and a negative contrast effect in eight of 29 patients with an atrial septal defect, although neither correlated quantitatively with defect diameter or magnitude of the left to right shunt. Echocardiographic assessment of defect size as small, moderate, or large showed a highly significant correlation with balloon measurement of defect diameter, although some overlap between the groups was evident. In contrast, the correlation between defect diameter and pulmonary to systemic blood flow ratio was poor, mainly because of highly variable shunting in patients with an anatomically large defect. Cross sectional echocardiography has high sensitivity and specificity in the diagnosis of the non-fenestrated atrial septal defect and provides quantitative information about defect diameter. Contrast studies do not add to the diagnostic value of imaging from the subcostal position. The poor correlation between defect size and the measured shunt suggests that the latter may not be the best criterion for surgical management and that size could be an important factor likely to influence both the long term prognosis and the decision for closure.

Adolescent↗
PubMed1999

Incidence of secondary pulmonary hypertension in adults with atrial septal or sinus venosus defects.

OBJECTIVE: To examine the incidence of raised pulmonary artery pressure and resistance in adults with isolated atrial septal defect within the oval fossa (so called secundum defect) or sinus venosus defect. DESIGN: A historical, retrospective, unrandomised study. SETTING: A tertiary referral centre. METHODS: Cardiac catheterisation was performed in all patients, with measurement of pulmonary artery pressure and resistance. Pulmonary to systemic flow ratio was calculated using the Fick principle. Pulmonary hypertension was defined as mean pulmonary artery pressure > 30 mm Hg, and increased resistance as an Rp/Rs ratio > 0.3. PATIENTS: All patients with a secundum atrial septal or sinus venosus defect who presented between July 1988 and December 1997 were enrolled in the study. RESULTS: Pulmonary artery pressure and resistance in the patients with sinus venosus defect (n = 31) was higher than in patients with atrial septal defect (n = 138). Pulmonary hypertension was present in 26% of patients with sinus venosus and in 9% of patients with atrial septal defect. The incidence of raised pulmonary vascular resistance was 16% in patients with sinus venosus and 4% in patients with atrial septal defect. The increase in resistance occurred at a younger age in sinus venosus defect than in atrial septal defect. CONCLUSIONS: Patients with sinus venosus defect have higher pulmonary pressures and resistances and develop these complications at younger age than patients with atrial septal defects. Thus they should be managed differently than patients with "simple" atrial septal defects.

Adult↗
PubMed1985

Significance of cardiac defects in the developing fetus: a study of spontaneous abortuses.

We investigated the impact of heart defects on the developing human fetus by examining 412 hearts from consecutive spontaneous abortuses. In each case, the cardiac morphology was correlated with the autopsy findings and the karyotype (unavailable in 115 hearts not successfully cultured). Of the 412 hearts, 10 (2.4%) contained structural defects (six ventricular septal defects, one atrial septal defect with ventricular septal defect, and one each coarctation, atrioventricular septal defect, and tetralogy of Fallot). Only one of 10 had major extracardiac malformations. Of the 277 fetuses with normal karyotype, three (1.1%) had heart defects. Of the 20 fetuses with abnormal karyotype, four (20%) had heart defects. In the remaining three fetuses with heart defects, the karyotype was not obtained. Thus (1) 57% of spontaneous abortuses with congenital heart defects contained major chromosomal abnormalities, (2) the spectrum of heart defects among spontaneous abortuses was similar to that among liveborns, and (3) since the prevalence of heart defects among fetuses without other major abnormalities was similar to that among liveborns, heart defects alone may not jeopardize the survival of a developing fetus.

Abortion, Spontaneous↗
PubMed1986

Color Doppler detection of multiple ventricular septal defects.

Combined two-dimensional and Doppler echocardiography has a high sensitivity and specificity for detection of isolated perimembranous ventricular septal defects. However, muscular or multiple ventricular septal defects may be difficult to diagnose with noninvasive methods, particularly in older children, necessitating angiography for accurate diagnosis. Detection of single and multiple ventricular septal defects with two-dimensional color flow mapping was compared with detection by standard two-dimensional imaging and Doppler. Both techniques were compared with four-chamber left ventricular angiography. Fifty-one patients (age 3 months to 25 years, mean 5.6 years) were studied. Eighteen had solitary ventricular septal defects, 18 had multiple ventricular septal defects, and 15 patients with intact ventricular septum served as a control group. At least one ventricular septal defect was detected by color Doppler and two-dimensional/Doppler methods in all patients with ventricular septal defect proved by angiography with no false positives. In the detection of multiple ventricular septal defects, the sensitivity of color Doppler was 72% and that of two-dimensional/Doppler was 38% (100% specificity in both). Color Doppler failed to identify multiple ventricular septal defects in five patients (two weighing less than 4 kg and three with reduced pulmonary blood flow). However, no large additional muscular defects were missed by imaging and color Doppler. Color Doppler is useful for the detection of ventricular septal defects and has higher sensitivity than two-dimensional/Doppler for multiple ventricular septal defects. The contribution of color Doppler appears to be in the detection of additional small muscular ventricular septal defects.

Adolescent↗
PubMed2006

Predictors of spontaneous closure of isolated secundum atrial septal defect in children: a longitudinal study.

OBJECTIVES: The goals were to assess the frequency of spontaneous closure of isolated secundum atrial septal defect in children and to identify predictors of spontaneous atrial septal defect closure. METHODS: A retrospective cohort study was performed in a tertiary care pediatric cardiology center. Consecutive patients (n = 200) diagnosed as having isolated atrial septal defects (no multiple or fenestrated atrial septal defects, no additional congenital heart disease, and no syndromes) were monitored for > 6 months with serial 2-dimensional echocardiography, according to a standardized protocol. RESULTS: The median age at diagnosis was 5 months (minimum: 0 months; maximum: 13.9 years). The atrial septal defect diameter at diagnosis was 4 to 5 mm in 40% of cases, 6 to 7 mm in 28% of cases, 8 to 10 mm in 21% of cases, and > 10 mm in 11% of cases. The median age at the final follow-up evaluation was 4.5 years (range: 6.8 months to 16.2 years). Thirty-four percent of atrial septal defects showed spontaneous closure, and 28% decreased to a diameter of < or = 3 mm. Logistic regression analysis revealed atrial septal defect diameter and age at diagnosis as independent predictors of spontaneous closure or regression to < or = 3-mm defect size. Of atrial septal defects with a diameter of 4 to 5 mm at diagnosis, 56% showed spontaneous closure, 30% regressed to a diameter of < or = 3 mm, and none required surgical closure. Of atrial septal defects with a diameter of > 10 mm at diagnosis, none closed spontaneously, whereas 77% required surgical or device closure. Gender and observation time were not associated with spontaneous atrial septal defect closure or regression to < or = 3 mm. CONCLUSIONS: In the present study population of children with atrial septal defects, 62% showed spontaneous closure (34%) or regression to < or = 3 mm (28%). Initial atrial septal defect diameter was the main predictor of spontaneous closure.

Adolescent↗
PubMed2005

Newborn screening for congenital heart defects: a systematic review and cost-effectiveness analysis.

OBJECTIVES: To provide evidence to inform policy decisions about the most appropriate newborn screening strategy for congenital heart defects, identifying priorities for future research that might reduce important uncertainties in the evidence base for such decisions. DATA SOURCES: Electronic databases. Groups of parents and health professionals. REVIEW METHODS: A systematic review of the published medical literature concerning outcomes for children with congenital heart defects was carried out. A decision analytic model was developed to assess the cost-effectiveness of alternative screening strategies for congenital heart defects relevant to the UK. A further study was then carried out using a self-administered anonymous questionnaire to explore the perspectives of parents and health professionals towards the quality of life of children with congenital heart defects. The findings from a structured review of the medical literature regarding parental experiences were linked with those from a focus group of parents of children with congenital heart defects. RESULTS: Current newborn screening policy comprises a clinical examination at birth and 6 weeks, with specific cardiac investigations for specified high-risk children. Routine data are lacking, but under half of affected babies, not previously identified antenatally or because of symptoms, are identified by current newborn screening. There is evidence that screen-positive infants do not receive timely management. Pulse oximetry and echocardiography, in addition to clinical examination, are alternative newborn screening strategies but their cost-effectiveness has not been adequately evaluated in a UK setting. In a population of 100,000 live-born infants, the model predicts 121 infants with life-threatening congenital heart defects undiagnosed at screening, of whom 82 (68%) and 83 (69%) are detected by pulse oximetry and screening echocardiography, respectively, but only 39 (32%) by clinical examination alone. Of these, 71, 71 and 34, respectively, receive a timely diagnosis. The model predicts 46 (0.5%) false-positive screening diagnoses per 100,000 infants with clinical examination, 1168 (1.3%) with pulse oximetry and 4857 (5.4%) with screening echocardiography. The latter includes infants with clinically non-significant defects. Total programme costs are predicted of pound 300,000 for clinical examination, pound 480,000 for pulse oximetry and pound 3.54 million for screening echocardiography. The additional cost per additional timely diagnosis of life-threatening congenital heart defects ranges from pound 4900 for pulse oximetry to pound 4.5 million for screening echocardiography. Including clinically significant congenital heart defects gives an additional cost per additional diagnosis of pound 1500 for pulse oximetry and pound 36,000 for screening echocardiography. Key determinants for cost-effectiveness are detection rates for pulse oximetry and screening echocardiography. Parents and health professionals place similar values on the quality of life outcomes of children with congenital heart defects and both are more averse to neurological than to cardiac disability. Adverse psychosocial effects for parents are focused around poor management and/or false test results. CONCLUSIONS: Early detection through newborn screening potentially can improve the outcome of congenital heart defects; however the current programme performs poorly, and lacks monitoring of quality assurance, performance management and longer term outcomes. Pulse oximetry is a promising alternative newborn screening strategy but further evaluation is needed to obtain more precise estimates of test performance and to inform optimal timing, diagnostic and management strategies. Although screening echocardiography is associated with the highest detection rate, it is the most costly strategy and has a 5% false-positive rate. Improving antenatal detection of congenital heart defects increases the cost per timely postnatal diagnosis afforded by any newborn screening strategy but does not alter the relative effects of the strategies. An improvement of timely management of screen positive infants is essential. Further research is required to refine the detection rate and other aspects of pulse oximetry, to evaluate antenatal screening strategies more directly, and to investigate the psychosocial effects of newborn screening for congenital heart defects.

Adolescent↗
PubMed2003

Echocardiographic considerations during deployment of the Helex Septal Occluder for closure of atrial septal defects.

The Helex Septal Occluder is a new device used to close atrial septal defects via interventional catheterization. In order to study the role of echocardiography during its use, and to describe the morphologic variants of defects suitable for closure with this occluder, we evaluated all patients undergoing intended closure of an atrial septal defect with the Helex occluder. A combination of transthoracic, transesophageal, three-dimensional, and intracardiac echocardiography were used before, during, and after the procedure to characterize anatomy, assess candidacy for closure, guide the device during its deployment, and evaluate results. Among the 60 candidates included in the study, 11 were excluded because of transesophageal echocardiographic and/or catheterization data obtained in the laboratory. Attempts at closure were successful in 46 patients, and unsuccessful in 3. We successfully treated four types of defects. These were defects positioned centrally within the oval fossa with appreciable rims along the entire circumference of the defect, defects with deficient or absent segments of the rim, defects with aneurysm of the primary atrial septum, and defects with multiple fenestrations. Follow-up transthoracic echocardiograms taken at a median of 7 months demonstrated no residual defects in 21, trivial residual defects in 17, and small residual defects in 8 patients. In 20 patients, three-dimensional reconstructions were used to characterize the morphology of the defect and the position of the device. Because transesophageal echocardiography was often limited by acoustic interference from the device, intracardiac echocardiography was utilized in 3 cases to overcome this limitation.

Adolescent↗
PubMed2005

[Linear insertion of the atrioventricular valves without defect].

On a first anatomical series of 52 hearts of trisomic 21 fetuses, published in June 2002, we described a new minor cardiac anomaly, belonging to the atrioventricular septal defect, with a linear insertion of the atrioventricular valves without defect. We want to confirm these data, on a larger series of 213 new hearts of trisomic 21 fetuses by adding a complementary section to the standard examination; 100% of controls have shown a normal insertion with an offsetting of the atrioventricular valves. On 113 out of these 213 hearts of trisomic 21 fetuses, with a so called "normal" heart at the standard examination showing no defect, the complementary section has shown that only 37.2% of these hearts have a normal insertion, whereas 62.83% show a linear insertion, without offsetting and without any septal defect. This linear insertion has been observed in all the different types of atrioventricular septal defect as a good hallmark for trisomy 21; but, since then, they have always been described associated with a septal defect, atrial or ventricular. Our hypothesis is that the linear insertion of the atrioventricular valves without defect is the minor form of the atrioventricular septal defect spectrum, taking place between the prior described partial types of atrioventricular septal defect, in which there is always a defect (ostium primum type atrial septal defect or inflow type ventricular septal defect), and the real normal heart. A precise description of the level of the complementary section and of the anatomic peculiarities of the linear insertion of the atrioventricular valves without defect would help its screening in fetal ultrasonography.

Autopsy↗
PubMed1987

[Diagnosis of atrial septal defect using magnetic resonance imaging].

We studied the morphological features of defects of the interatrial septum using magnetic resonance imaging (MRI) to determine the sizes of defects and other abnormalities. MR images were obtained in 28 patients with atrial septal defect, including five cases with complicated anomalies (two with Ebstein's anomaly, one pentalogy of Fallot, and one anomalous pulmonary vein connection and azygos continuation). Images were also obtained in the control subjects including seven normal volunteers and 142 patients with various acquired heart diseases. The diagnosis of atrial septal defect was established by cardiac catheterization, angiography and two-dimensional echocardiography prior to the MRI studies, and in 14 patients, the diagnosis was confirmed by surgery. The MRI unit had a superconducting magnet and operated at 0.25 or 0.50 Tesla. A spin echo pulse sequence was used with an echo time of 40 or 60 msec. At the beginning of this study, non-gated MRI images were obtained in the 28 controls and in three patients with atrial septal defect. Nongated MRI could not image the anatomical structure of the interatrial septa of 12 of the 28 controls, or any of the three patients with atrial septal defect. Nongated MRI was, therefore, inadequate for visualizing cardiac anatomy. Gated MRI images were obtained in 141 controls and in 25 patients with atrial septal defect. Gated MRI revealed the interatrial septum, interventricular septum, atrioventricular septum, mitral valve, tricuspid valve and other intracardiac structures in most subjects. In 17 control subjects (12%), however, there was a very faint signal from the central portion of the interatrial septum. In these instances, there was a gradual fading of the signal of the interatrial septum, so that they could be distinguished from the atrial septal defect. The sudden disappearance of the signal from the interatrial septum was observed by gated MRI in all 25 patients with atrial septal defect. The sizes of the defects by MRI coincided with the findings at surgery in all 14 patients. MRI showed right atrial dilatation, right ventricular hypertrophy and dilatation, and pulmonary artery dilatation in most of the patients having atrial septal defect. Complex anomalies associated with atrial septal defect were also clearly shown by MRI, such as displacement of the tricuspid leaflets in two patients with Ebstein's anomaly, and anomalous pulmonary venous connection and persistent left superior vena cava in one patient. These results indicated that gated MRI is a valuable noninvasive method of diagnosing atrial septal defect and complicating anomalies.

Adolescent↗
PubMed1998

Periodontal healing of canine experimental grade-III furcation defects treated with autologous fibrinogen and absorbable barrier membrane.

OBJECTIVE: To determine the effects of autologous fibrinogen (AF) and absorbable barrier membrane (ABM) on periodontal healing of canine experimental grade-III furcation defects. ANIMALS: 18 conditioned, laboratory-source, adult Beagles. PROCEDURE: Defects were developed bilaterally at the second and fourth premolars and maintained for 12 weeks. Defects were treated with AF, ABM, AF and ABM, or debridement. Digital subtraction radiography, histologic evaluation, and histomorphometric analysis of defect healing was done at 1, 3, and 6 months after treatment to determine percentage increases in bone volume, height, area, and length of periodontal regeneration along the perimeter of the defect. RESULTS: Comparison of defects at post-treatment intervals indicated significantly greater healing of debridement and AF-treated defects, compared with ABM-treated defects at 3 months; however, by 6 months, there were no significant differences in defect healing for all histomorphometric variables. Defects treated with ABM were associated with significantly less root ankylosis than other treatments. Defects treated with debridement had significantly greater increases in bone volume at 6 months after treatment, compared with groups treated with ABM. There was a significant correlation between regenerated bone area, bone volume, and periodontal regeneration for all treatments at 3 and 6 months after treatment. CONCLUSION AND CLINICAL RELEVANCE: Use of AF and ABM did not enhance the amount of periodontal healing, compared with debridement only. The ABM-treated defects were essentially devoid of root ankylosis. Grade-III furcation defects may respond equally well to conservative periodontal surgery or guided tissue regenerative techniques. The prevention of root ankylosis is a substantial benefit favoring this latter method of treatment.

Absorption↗
PubMed2000

Assessment of resorbable bioactive material for grafting of critical-size cancellous defects.

Bioactive glasses form a surface apatite layer in vivo that enhances the formation and attachment of bone. Sol-gel Bioglass graft material provides greater nanoscale porosity than bioactive glass (on the order of 50-200 A), greater particle surface area, and improved resorbability, while maintaining bioactivity. This study histologically and biomechanically evaluated, in a rabbit model, bone formed within critical-sized distal femoral cancellous bone defects filled with 45S5 Bioglass particulates, 77S sol-gel Bioglass, or 58S sol-gel Bioglass and compared the bone in these defects with normal, intact, untreated cancellous bone and with unfilled defects at 4, 8, and 12 weeks. All grafted defects had more bone within the area than did unfilled controls (p < 0.05). The percentage of bone within the defect was significantly greater for the 45S5 material than for the 58S or 77S material at 4 and 8 weeks (p < 0.05), yet by 12 weeks equivalent amounts of bone were observed for all materials. By 12 weeks, all grafted defects were equivalent to the normal untreated bone. The resorption of 77S and 58S particles was significantly greater than that of 45S5 particles (p < 0.05). Mechanically, the grafted defects had compressive stiffness equivalent to that of normal bone at 4 and 8 weeks. At 12 weeks, 45S5-grafted defects had significantly greater stiffness (p < 0.05). At 8 and 12 weeks, all grafted defects had significantly greater stiffness than unfilled control defects (p < 0.05). In general, the 45S5-filled defects exhibited greater early bone ingrowth than did those filled with 58S or 77S. However, by 12 weeks, the bone ingrowth in each defect was equivalent to each other and to normal bone. The 58S and 77S materials resorbed faster than the 45S5 materials. Mechanically, the compressive characteristics of all grafted defects were equivalent or greater than those of normal bone at all time points.

Animals↗
PubMed2001

Inclusion of early fetal deaths in a birth defects surveillance system.

This investigation evaluated the impact of collecting data on early fetal deaths (less than 20 weeks' gestation) on a birth defects surveillance system. Data were obtained from the Hawaii Birth Defects Program (HBDP), a statewide registry for Hawaii with active case ascertainment methodology. In 1986 through 1997, 257 early fetal deaths with birth defects were identified, representing 2.2% of the total birth defects cases. Two hundred sixteen (84.1%) of the early fetal deaths had chromosomal defects (mainly trisomies, polyploidies, and Turner syndrome) and 59 (23.0%) had structural defects. Most (65.4%) of the early fetal deaths with chromosomal defects occurred at 8-12 weeks' gestation, and 62.3% of the early fetal deaths with structural defects occurred at 16-19 weeks' gestation. For half of the 26 specific birth defects examined, early fetal deaths accounted for at least 4% of all cases. The proportion of total birth defects cases accounted for by early fetal deaths increased over the 12-year period of the study (p = 0.003). Most of this secular trend appeared to result from an increase over time in early fetal deaths where a birth defect was prenatally detected (p = 0.004). Although ascertainment of early fetal deaths is not believed to be complete, their inclusion in a birth defects registry may be beneficial because of confusion about the pregnancy outcome and/or gestational age reported in the medical record, their importance in cluster investigations, and their contribution to birth defects prevention strategies.

Chromosome Aberrations↗