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PubMed1987

Long-term follow-up after aortic valvuloplasty and defect closure in ventricular septal defect with aortic regurgitation.

The clinical course was studied in 25 patients with ventricular septal defect (VSD) and aortic regurgitation (AR) who had undergone aortic valvuloplasty and VSD closure. Twelve patients had a doubly committed subarterial VSD and 13 had a perimembranous type of VSD. Preoperatively, progressive hemodynamic disturbance after the onset of AR occurred in 11 patients (44%). The follow-up period extended from 6 months to 23 years (mean 10 years). Four patients required prosthetic valve replacement after valvuloplasty. One of these had had initial improvement of the AR but required valve replacement 20 years later; the condition of the other 3 did not improve initially and their valves were replaced 1 month to 8.5 years later. Four other patients had no initial improvement as a result of valvular reconstructive surgery, but the AR did not progress and remained hemodynamically well tolerated. Hence, the overall success rate of the valvuloplasty, defined as improving or preventing progressive AR, was 21 of 25 (84%). Since initial and long-term improvement in aortic valve function can be expected in most patients after valvuloplasty and closure of the VSD, early surgical intervention is recommended in patients with a VSD and AR.

Aortic Valve↗
PubMed2001

The risk for congenital heart defects in offspring of individuals with congenital heart defects.

BACKGROUND: Congenital heart defects (CHDs) occur in approximately 1% of all live births. Although most CHDs are of unknown etiology, a family history of CHDs is a known risk factor, and offspring of individuals with CHDs are at a higher risk of having CHDs. The aim of this study was to investigate the relative risk for CHDs to offspring of individuals with CHDs. METHODS: The prevalence rates of CHDs in offspring of 203 individuals with CHDs and 282 individuals without CHDs were investigated. The study participants completed a questionnaire that included information on medical and reproductive history, lifestyle indicators, and family history of CHDs and other congenital malformations. The prevalence rates of CHDs in offspring were calculated. RESULTS: The prevalence of CHDs was 3.1% (18/575) in offspring of individuals with CHDs and 1.3% (8/589) in offspring of individuals without CHDs. The adjusted odds ratio for CHDs to offspring of parents with CHDs was 1.73 (95% confidence interval [95% CI] 0.89-2.44, p=0.02). The estimated relative risk for offspring to females with CHD was higher than for males [2.3 (95% CI 1.1-4.7, p=0.03) versus 1.31 (95% CI 0.48-4.30, p=0.66), respectively]. There was no suggestion of association between CHDs and maternal smoking, alcohol consumption, and use of medication during pregnancy. CONCLUSIONS: Offspring of parents with CHDs are at a higher risk for CHDs compared with the general population. Couples where one member is affected with CHD should receive pre-conceptional or pre-natal genetic counseling and should be informed about the magnitude of the potential risk of CHDs to the offspring.

Family Health↗
PubMed2002

A polymorphism, R653Q, in the trifunctional enzyme methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase/formyltetrahydrofolate synthetase is a maternal genetic risk factor for neural tube defects: report of the Birth Defects Research Group.

Women who take folic acid periconceptionally reduce their risk of having a child with a neural tube defect (NTD) by >50%. A variant form of methylenetetrahydrofolate reductase (MTHFR) (677C-->T) is a known risk factor for NTDs, but the prevalence of the risk genotype explains only a small portion of the protective effect of folic acid. This has prompted the search for additional NTD-associated variants in folate-metabolism enzymes. We have analyzed five potential single-nucleotide polymorphisms (SNPs) in the cytoplasmic, nicotinamide adenine dinucleotide phosphate-dependent, trifunctional enzyme methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase/formyltetrahydrofolate synthetase (MTHFD1) for an association with NTDs in the Irish population. One SNP, R653Q, in this gene appears to be associated with NTD risk. We observed an excess of the MTHFD1 "Q" allele in the mothers of children with NTD, compared with control individuals. This excess was driven by the overrepresentation of QQ homozygotes in the mothers of children with NTD compared with control individuals (odds ratio 1.52 [95% confidence interval 1.16-1.99], P=.003). We conclude that genetic variation in the MTHFD1 gene is associated with an increase in the genetically determined risk that a woman will bear a child with NTD and that the gene may be associated with decreased embryo survival.

Aminohydrolases↗
PubMed1976

Defective-interfering particles of Semliki Forest Virus: structural differences between standard virus and defective-interfering particles.

Serial passaging of Semlike Forest virus in BHK cells at a constant input multiplicity of 50 p.f.u./cell resulted in a 4 log10 drop in yield of infectious virus by passage 9. An interference analysis showed that this drop was due to the presence of defective-interfering (DI) particles. Attempts were made to separate the DI particles from standard virus by equilibrium and velocity centrifugation. Only equilbrium centrifugation on CsCl resolved the DI particles (identified by interference analyses) from standard virus. The buoyant density of the DI particles (1.23 g/ml) was higher than that of standard virus (p = 1-20 g/ml). No difference was observed between the structural porteins of standard virus and DI particles. Analysis of the RNA of standard virus and DI particles showed that whereas standard virus contained only 42S RNA (mol. wt. approx. 4-2 X 10(6), DI particles contained two small pieces of RNA of mol. wt. 0.81 and 0-75 X 10(6) respectively. Infectivity assays showed that these low mol. wt. species were not only non-infectious but also interfered with the infectivity of 42S RNA from standard virus. Nucleocapsids derived from purified DI particles had a buoyant density 0-02 g/ml greater than the nucleocapsids from standard virus. Analysis of the RNA from DI nucleocapsids showed it to be entirely of the low mol. wt. class. To account therefore for the density difference not only between DI particles and standard virus but also between their respective nucleocapsids we propose that each SFV DI particle contains several molecules of the low mol. wt. RNA species.

Cell Line↗
PubMed1983

Herpes simplex virus defective genomes: structure of HSV-1 ANG defective DNA of class II and encoded polypeptides.

Sequence organization and origin of HSV-1 strain Angelotti (ANG) class II defective DNA (HSV-1 ANG dDNA1) were examined in detail by establishing physical maps and by molecular cloning. dDNA1 consists of concatemers of tandem repeat units in which sequences from the UL region spanning map coordinates 0.37 to 0.415 of standard HSV ANG DNA are covalently linked to TRS/IRS sequences. The size of the repeat unit was determined to be about 8.9 kilobase pairs (kb), comprising sequences of 7.3 kb from UL and 1.6 kb from TRS/IRS regions. UL sequences were delineated by restriction enzyme sites KpnI N-P and EcoRI F-M, and were colinear with the corresponding sequences of the standard (wild-type) virus genome. Expression of dDNA1 was studied in African green monkey kidney cells and in Xenopus laevis oocytes. A major polypeptide of approx. mol. wt. 135 000 (135K) was overproduced, suggesting that this protein was encoded by dDNA1. By several parameters, e.g. size, immune cross-reactivity, and affinity for native and denatured DNA, the 135K polypeptide was identified as the major HSV DNA-binding protein. It was further shown that the repeat unit contains part of the DNA polymerase gene as demonstrated by its ability to rescue some mutations in this gene.

Base Sequence↗
PubMed1987

Continuing coevolution of virus and defective interfering particles and of viral genome sequences during undiluted passages: virus mutants exhibiting nearly complete resistance to formerly dominant defective interfering particles.

We quantitatively analyzed the interference interactions between defective interfering (DI) particles and mutants of cloned vesicular stomatitis virus passaged undiluted hundreds of times in BHK-21 cells. DI particles which predominated at different times in these serial passages always interfered most strongly (and very efficiently) with virus isolated a number of passages before the isolation of the DI particles. Virus isolated at the same passage level as the predominant DI particles usually exhibited severalfold resistance to these DI particles. Virus mutants (Sdi- mutants) isolated during subsequent passages always showed increasing resistance to these DI particles, followed by decreasing resistance as new DI particles arose to predominate and exert their own selective pressures on the virus mutant population. It appears that such coevolution of virus and DI particle populations proceeds indefinitely through multiple cycles of selection of virus mutants resistant to a certain DI particle (or DI particle class), followed by mutants resistant to a newly predominant DI particle, etc. At the peak of resistance, virus mutants were isolated which were essentially completely resistant to a particular DI particle; i.e., they were several hundred thousand-fold resistant, and they formed plaques of normal size and numbers in the presence of extremely high multiplicities of the DI particle. However, they were sensitive to interference by other DI particles. Recurring population interactions of this kind can promote rapid virus evolution. Complete sequencing of the N (nucleocapsid) and NS (polymerase associated) genes of numerous Sdi- mutants collected at passage intervals showed very few changes in the NS protein, but the N gene gradually accumulated a series of stable nucleotide and amino acid substitutions, some of which correlated with extensive changes in the Sdi- phenotype. Likewise, the 5' termini (and their complementary plus-strand 3' termini) continued to accumulate extensive base substitutions which were strikingly confined to the first 47 nucleotides. We also observed addition and deletion mutations in noncoding regions of the viral genome at a level suggesting that they probably occur at a high frequency throughout the genome, but usually with lethal or debilitating consequences when they occur in coding regions.

Amino Acid Sequence↗
PubMed1984

Systolic time intervals in isolated septal defects before and after corrective surgery in female patients. I. Atrial septal defect.

Systolic time intervals (STI) were evaluated in 19 female patients with uncomplicated ostium secundum atrial septal defect (ASD), before, shortly after (within 2 months) and a long time after the corrective surgery (mean 13.2 years). The measurements were obtained from simultaneous high speed photographic recordings of electrocardiogram, external carotid pulse and phonocardiogram. Before the operation, a significant prolongation of Q-I heart sound interval was detected, together with a less prominent but statistically significant shortening of the left ventricular ejection time; the above alterations were not correlated with the magnitude of the shunt and disappeared shortly after corrective surgery. The STI were still normal a long time after surgical closure of ASD. In accordance with hemodynamic studies reported by other authors, our results confirm that the deviations of STI observed in ASD are due to a reduced diastolic filling of the left ventricle secondary to an apparent decreased distensibility.

Adolescent↗
PubMed1984

Systolic time intervals in isolated septal defects before and after corrective surgery. II. Ventricular septal defect.

Systolic time intervals (STI) were analyzed in 34 patients with isolated ventricular septal defect (VSD) and undirectional left-to-right shunt. 14 of the patients who underwent corrective surgery were followed-up for at least 10 years. The measurements were obtained from simultaneous high speed photographic recordings of electrocardiogram, external carotid pulse and phonocardiogram. Before the operation the Q-I sound interval and, consequently, the pre-ejection period were significantly prolonged and the left ventricular ejection time significantly abbreviated, the degree of abbreviation relating with the magnitude of the shunt. The above deviations persisted after corrective surgery, and only several years after the operation the parameters studied became normal. It is concluded that the most likely explanation for these abnormalities is the depressed contractility of the left ventricle, secondary to the long-standing volume overload, which tends to persist after corrective surgery.

Adolescent↗
PubMed1986

Relevance of location of defect and pulmonary vascular resistance to the intracardiac pattern of left-to-right shunt flow in dogs with experimental ventricular septal defect.

Left-to-right (L-R) shunting across a ventricular septal defect (VSD) often involves a direct VSD-pulmonary arterial component (jet) that surges from the VSD immediately into the pulmonary artery. We used the thermodilution technique in dogs with acute experimental VSD to quantify this component. In dogs with supracristal VSD (n = 7), the direct component represented 76 +/- 4% (mean +/- SE) of the total L-R shunt on average, vs 39 +/- 7% (p less than .001) of the total in dogs with infracristal VSD and the same level of L-R shunting (n = 6). The direct component can be expected to impose additional hyperkinetic forces on the pulmonary artery since it is driven by the left ventricular pressure. Although not yet clinically proven, we speculate therefore that patients with supracristal VSD may be at greater risk of becoming jeopardized by late-onset pulmonary vascular obstructive disease. Since a part of the total shunt other than the direct component dropped into the right ventricle, the right ventricle bore only 24% of the total shunt in supracristal VSD, but 61% in infracristal VSD. We also found that the amount of direct component was decreased, and therefore another part must have increased, as the pulmonary vascular resistance was artificially raised. As a second speculation, therefore, we suggest that patients with supracristal VSD may have less enlargement of the right ventricle than those with infracristal VSD before pulmonary hypertension develops.

Animals↗
PubMed2002

[Is minimal skin incision and partial sternotomy approach for congenital heart defects less invasive?; evaluation of SIRS on ventricular septal defect].

OBJECTIVES: Minimally invasive cardiac surgery (MICS) has been developed to offer patients the benefits of open heart operations with limited skin incision. But it is unclear whether this procedure is less invasive. We evaluate postoperative duration of systemic inflammatory response syndrome (SIRS) on ventricular septal defect (VSD). METHODS: From August 1997 to March 2000, 47 patients VSD underwent total repair by the minimal skin incision and lower partial median sternotomy (MICS group). We compared duration of SIRS between MICS and conventional method group (n = 14) and between early MICS and recent MICS group. We also evaluated the relationship between MICS and postoperative clinical course. RESULTS: Duration of SIRS of MICS group were obviously shorter than that of conventional method group (p < 0.05). That of recent MICS group is also significantly shorter than that of early MICS group (p < 0.05). Operative time, bypass time, postoperative intubation time and length of skin incision were related duration of SIRS. CONCLUSIONS: The results of this study indicate that MICS for VSD may be less invasive method.

Cardiac Surgical Procedures↗
PubMed1991

[A case of ventricular septal defect associated with active infective endocarditis which was successfully treated by triple valve replacement and ventricular septal defect patch closure].

A 47-year-old man was hospitalized in May, 1990, because of breathlessness and continuous fever which appeared about 4 weeks after he had had his periodontic tooth removed in December, 1989. He had been diagnosed as having ventricular septal defect (VSD) at the age of 6 years. When he was hospitalized, he was in a condition of class IV by NYHA classification, with a white blood cell count of 17,300/mm3, an increase in CRP, a red blood cell sedimentation rate of 108 mm/hr, and positive alpha-streptococcus in blood culture. His cardiothoracic ratio was 64% with signs of pulmonary congestion on a chest X-ray film. Echocardiography revealed the presence of VSD and huge vegetations on the tricuspid, mitral and aortic valves. He was considered to have active infective endocarditis (AIE) which had presumably been provoked by VSD and the tooth removal. Penicillin G at a daily dose of 20 million units and gentamicin at a daily dose of 80 mg were intravenously administered to treat the alpha-streptococcus infection for about 4 weeks. Furosemide was used for congestive heart failure. Since, although his cardiac function appeared to have been improved, the signs and symptoms of the infection persisted, triple valve replacement for the tricuspid, mitral and aortic valves and patch closure of the VSD were performed 4 weeks after the hospitalization. The operation revealed inflammatory lesions extending from the endocardium of the right ventricle to the mitral valves through the VSD, and huge vegetations on the tricuspid, mitral and aortic valves. The operation was successful and the inflammatory areas gradually disappeared.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve↗
PubMed1991

[Two cases of atrial septal defect diagnosed by two-dimensional Doppler echocardiography: comparison with other methods for detecting atrial septal defect].

We describe two cases of atrial septal defect(ASD) diagnosed by chance with two-dimensional Doppler echocardiography(2DD) which was carried out for another purpose. There were no findings characteristic of ASD such as systolic murmurs in the pulmonary area, incomplete right bundle branch block pattern on electrocardiograms, increased hilar shadow on chest films or increased right ventricular chamber diameter in two-dimensional echocardiography. However, the 2DD showed blood flow crossing through the atrial septum. Cardiac catheterization confirmed the presence of a small ASD. ASD diagnosed by 2DD alone without other classical characteristic signs of ASD indicates that the ASD is small and clinically insignificant as it is with Doppler valvular heart disease.

Adult↗
PubMed1989

[Quantitative-morphometric characterization of the lung structure in congenital heart defects exemplified by Fallot disease and isolated ventricular septal defect].

The aim of this study was to investigate the possibility of determination of lung changes in congenital deformity of heart and vessels by the method of Weibel and Elias (1967) for count of points in the lung (volume of alveoli and interstitium). The results show that this method is suitable for the estimation of quantitative changes in Morbus Fallot. In order to decide the degree of arteriosclerosis an additional measurement of the wall thickness of lung vessels is necessary in cases of ventricular septal defect. The arteriosclerosis is an important factor for the secondary variations, especially of the right heart. A field of application of this method could be the praeoperative lung biopsy for the clarification of the question of operability.

Adolescent↗
PubMed1995

A genetic defect in 5,10 methylenetetrahydrofolate reductase in neural tube defects.

It is now well-established that folic acid, taken peri-conceptionally, can reduce the risk of neural tube defects (NTDs). Recent work has demonstrated that an abnormality of homocysteine metabolism is a critical factor. The gene for 5,10 methylenetetrahydrofolate reductase, an enzyme important in homocysteine metabolism, was studied in relation to NTDs. To determine the frequency of the allele for the thermolabile form of the reductase, DNA samples were collected from people with NTDs, parents of people with NTDs, and normal controls. Of 82 people with NTDs, 15 (18.3%) were homozygous for the abnormal, thermolabile allele. This was significantly higher (p = 0.01) than the rate of 6.1% in the control population (odds ratio 3.47, 95% CI 1.28-9.41). This is the first specific genetic abnormality to be identified in NTDs. It explains the association between some NTDs and elevated homocysteine, given that the reductase is important in homocysteine metabolism. It also explains how folic acid supplementation prevents some NTDs, by overcoming a partial block in the conversion of 5,10 methylenetetrahydrofolate to 5 methyltetrahydrofolate. Genetic screening could identify women who will require folic acid supplements to reduce their risk of having a child with an NTD.

Case-Control Studies↗