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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The morphology of the ventricular septal defect and associated malformations of the specialised conducting system in isolated ventricular septal defect and hearts with more complex malformations

Smith, A. January 1984 (has links)
No description available.
2

A molecular genetic investigation of chromosome 21 and Down's syndrome

Howard, Catherine Mary January 1995 (has links)
No description available.
3

The aetiology of atrioventricular septal defect

Wilson, Lynne January 1966 (has links)
No description available.
4

Cardiovascular malformation : an analysis of genetic contribution

Burn, John January 1991 (has links)
No description available.
5

Molecular genetic investigation of hypoplastic left heart syndrome

Phillips, Helen M. January 2002 (has links)
No description available.
6

Pregnancy among women with congenital heart defects: outcomes for mother and child

Leisner, Michelle 13 June 2019 (has links)
Congenital Heart Defects (CHDs), structural heart defects that are present at birth, are prevalent in approximately 1% of live births. While, historically, the presence of such defects was associated with a heightened risk of mortality, advances in medicine have allowed nearly 85% of individuals with CHDs to live into adulthood. As such, many of these individuals are reaching reproductive age and are becoming pregnant. In order to understand the implications of pregnancy among women with CHDs, a literature review was undertaken in order to elucidate the conditions that may present to the mother, as a product of the underlying defect, as well as to discern the impact of a maternal CHD on the child. Pregnancy induces hemodynamic alterations, such as an increase in stroke volume and heart rate (and thus cardiac output), and brings about an increase in blood volume. In populations with CHD, these hemodynamic changes may induce particular risks to the mother, as her cardiac condition may obstruct her ability to cope to with the heightened stress on the heart. Moreover, given that the heart may not function in an ideal manner, a less than ideal environment is present in-utero. Women with CHD suffer from elevated cardiovascular and obstetric complications, with the risk of some cardiovascular events extending into the post-partum period. During pregnancy, approximately 11% of women with CHD will experience a cardiovascular complication; this risk is highest among those with complex forms of the defect. Arrhythmia, specifically, is the most common complication, and will occur in 4.5% of pregnancies. Heart failure is also frequent, occurring in 4% to 5% of pregnancies, with the highest risk presenting in those patients with Eisenmenger syndrome and those with cyanotic forms of CHD. Pulmonary edema and thrombolytic events are also present in this population with a higher prevalence than in a healthy pregnant population. In the 6-month period after delivery, 12% of women with CHD will experience a cardiac event, with arrhythmia and heart failure as the most common complications. Obstetric complications occur in approximately 5% of pregnancies among women with CHDs, with 11% experiencing premature labor, 8.4% experiencing post-partum hemorrhage and 5.5% experiencing pregnancy-induced hypertension. Miscarriage occurs in 15% of pregnancies, with a dose-response type relationship associated with the severity of the underlying defect, as miscarriage occurs in up to 66% of pregnancies in those with Fontan palliation. Premature rupture of membranes occurs in 3.5% of pregnancies, with half of these cases occurring to patients with transposition of the great arteries. Termination of pregnancy also occurs in 5% to 8% of pregnancies, given high risk of complications to both mother and fetus. While preeclampsia is expected to occur in approximately 2-3% of pregnancies, this risk does not exceed what occurs in a healthy population. With regard to the impact of maternal CHD on the fetus, events occurring to the fetus/neonate include preterm delivery, small for gestational age, respiratory distress syndrome, intraventricular hemorrhage, and neonatal death. Between 1.5% and 2% of pregnancies will terminate in fetal mortality. Premature birth is likely in 12% to 20% births, with of 8% of neonates born as small for gestational age. Moreover, 3.5% of children born to mothers with CHD will present with CHD, themselves. Long-term effects of maternal CHD are not well-described. Despite these complications, pregnancy among women with CHD is well-tolerated and only in very few cases of those presenting with severe defects, is pregnancy counter-indicated. However, in order to mitigate risks, pre-pregnancy counseling is recommended in all women with CHD, regardless of severity of the defect. Counseling should include an overview of the form of defect, any surgical or medicinal interventions undertaken in response to the defect, an echocardiography, an exercise stress test, among other evaluations. Monitoring of the pregnancy should continue throughout gestation and delivery should occur in a specialized care facility and the mother and fetus should be monitored by a consortium of cardiologists, obstetricians, anesthesiologists, midwives. Monitoring of the mother should extend into the post-partum period until any cardiovascular or hemodynamic pregnancy-related alterations have returned to normal.
7

An anatomical and retrospective clinical study of interventricular septal defects

Osman, Mohseena 11 April 2013 (has links)
A ventricular septal defect occurring on its own is a congenital defect of the interventricular septum of the heart causing varying degrees of increased pulmonary blood flow and associated clinical symptoms. It may also occur in association with obstruction in the right ventricle resulting in diminished pulmonary blood flow. Very little is documented about the incidence of ventricular septal defects in South African children. The aim of this study was to briefly review the embryology and consider the normal anatomy of the interventricular septum. In addition, the clinical and surgical notes of all children that underwent surgical repair of ventricular septal defects (these included isolated ventricular septal defects, those with multiple ventricular septal defects, as well as those associated with tetralogy of Fallot and double chambered right ventricle) referred to the paediatric cardiothoracic unit at the Charlotte Maxeke Academic Hospital, from the Paediatric Cardiology units at the Charlotte Maxeke Academic Hospital, Chris Hani Baragwanath Academic Hospital and the Rahima Moosa Hospitals between 2001 and 2004, were analysed for the position, number of and size of ventricular septal defects. For this purpose, 11 cadaveric neonatal hearts were dissected while seven post-mortem specimens of the heart, four with isolated ventricular septal defects and three with tetralogy of Fallot were analysed. In addition, 50 cases of isolated ventricular septal defects, 42 cases with tetralogy of Fallot and eight cases with double chambered right ventricle were retrospectively reviewed. The membranous and the muscular septum made up the largest components of the interventricular septum in the normal neonatal hearts. A perimembranous ventricular septal defect was the most common type of defect diagnosed in these patients (the majority of the patients were Black children), 78% of cases with a single isolated ventricular septal defect, 90% in patients with tetralogy of Fallot, and 75% in the group with double chambered right ventricle. The average sizes of all perimembranous defects (from the echocardiogram) were classified as small, moderate or large. An additional interesting finding was prolapse of the right coronary cusp of the aortic valve into the isolated ventricular septal defect and occurred in 22% (11 out of 50) of patients. Aortic regurgitation occurred in association with prolapse of the right coronary cusp in 54.5% (5 out of 11) of cases. This prevalence in black patients is much higher than has been documented in White or Japanese children. Non-compaction of the left ventricle was seen in one post-mortem specimen in association with a perimembranous ventricular septal defect and dilated cardiomyopathy. This recently described abnormality is alluded to in the discussion. Attention is drawn to the abnormality known as double chambered right ventricle, where the size of the ventricular septal defect is variable and where the site of obstruction in the right ventricle is caused by muscle bundles lower than that seen in tetralogy of Fallot. Knowledge of ventricular septal defects found in South African children will help in the assessment and care of these patients with one of the most common congenital cardiac malformations.
8

Descriptive Analysis of Ebstein Anomaly in the National Birth Defects Prevention Study, 1997-2007

Colarusso, Tiffany 11 May 2012 (has links)
There is relatively little epidemiologic information about Ebstein anomaly (EA) ─ a rare congenital heart defect. Thus, we analyzed characteristics of EA in a geographically and ethnically diverse population. Data from the National Birth Defects Prevention Study were used to study infants born from 1997-2007 with EA. Birth prevalence and prevalence ratio (PR) estimates were derived from the number of affected infants per 10,000 live births in the catchment area. Case characteristics were examined, stratified by the presence of other cardiac and extracardiac defects. Predictive modeling using logistic regression was conducted to understand infant mortality risk factors. There were 249 cases with EA, for a birth prevalence of 0.55/10,000 live births. Other cardiac defects were present in 41.0% and extracardiac defects in 10% of cases. Prevalence was higher among multiple births compared to singletons (PR 2.41, 95% confidence interval (CI) 1.46-3.92) and preterm compared to term infants (PR 1.84, 95% CI 1.27-2.64). Compared to EA cases without other defects, those with additional defects were more likely to die (crude Odds Ratio (cOR) 4.07, 95% CI 1.71-9.93) or undergo cardiac surgery (cOR 6.06, 95% CI 2.78-13.49). Risk for death during infancy was increased by being small for gestational age (adjusted (a) OR 2.97, 95% CI 1.13-7.76) and having extracardiac defects (aOR 6.31, 95% CI 2.28-17.52). Some findings are consistent with previous work, but further studies of EA could clarify risk factors for occurrence and mortality. Knowing population characteristics could guide development of prevention strategies and may improve clinical care.
9

A molecular genetic investigation of the human COL6A1 gene region on chromosome 21

Trikka, Dimitra January 1998 (has links)
No description available.
10

Molecular analysis of the Ellis-van Creveld critical region

Woods, Kathryn Sage January 1999 (has links)
No description available.

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