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Besides the AV-valve problems there are frequent rhythm and conduction disorders; atrial fibrillation, supraventricular tachycardia, complete heartblock or sinus dysfunction. Depending on the kind of disorder patients can require medical treatment or a pacemaker. | Besides the AV-valve problems there are frequent rhythm and conduction disorders; atrial fibrillation, supraventricular tachycardia, complete heartblock or sinus dysfunction. Depending on the kind of disorder patients can require medical treatment or a pacemaker. | ||
== Patent ductus arteriosus == | |||
=== Case report === | |||
=== Introduction === | |||
The ductus arteriosus (DA) is a fetal vascular connection between the main pulmonary artery and the descending aorta that diverts blood away from the pulmonary bed (figure 6). After birth, the DA undergoes active constriction and eventual obliteration. A patent ductus arteriosus (PDA) occurs when the ductus fails to completely close postnatally. | The ductus arteriosus (DA) is a fetal vascular connection between the main pulmonary artery and the descending aorta that diverts blood away from the pulmonary bed (figure 6). After birth, the DA undergoes active constriction and eventual obliteration. A patent ductus arteriosus (PDA) occurs when the ductus fails to completely close postnatally. | ||
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PDA may present with other congenital heart lesions, especially those associated with hypoxemia. PDA should be considered when the clinical features of left-to-right shunt seem out of proportion to the particular lesion being considered. | PDA may present with other congenital heart lesions, especially those associated with hypoxemia. PDA should be considered when the clinical features of left-to-right shunt seem out of proportion to the particular lesion being considered. | ||
=== Evaluation === | |||
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Echocardiography is a very sensitive and specific method to identify the left-to-right shunt. | Echocardiography is a very sensitive and specific method to identify the left-to-right shunt. | ||
=== Treatment and outcome === | |||
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Percutaneous PDA occlusion was first introduced in 1967 and provides an alternative to surgical ligation. Many different techniques have been developed, however the two techniques most commonly used are coils or occlusion devices. Both techniques lead to a full occlusion of the PDA and normalization of left ventricular hemodynamics. | Percutaneous PDA occlusion was first introduced in 1967 and provides an alternative to surgical ligation. Many different techniques have been developed, however the two techniques most commonly used are coils or occlusion devices. Both techniques lead to a full occlusion of the PDA and normalization of left ventricular hemodynamics. | ||
== Coarctation of the aorta == | |||
=== Case report === | |||
=== Introduction === | |||
Coarctation of the aorta is a narrowing of the thoracic aorta, typically located in the region of the obliterated ductus arteriosum. (figure 9) The relation to the position of the left subclavian artery differs, in most patients the left subclavian artery is located anterior of the coarctation. Aortic coarctation is frequently associated with diffuse hypoplasia of the aortic arch and isthmus. | |||
The incidence of coarctation of the aorta is 4 in 10.000 live births, accounting for 5–9% of the children with congenital heart defects, occurring two to five times more frequently in males than females. | |||
Coarctation of the aorta can be an isolated congenital heart defect, however usually it coincides with other congenital defects. Associated heart defects are patent ductus arteriosus, ventricular septal defect, mitral valve stenosis and valvular and subvalvular aortic stenosis. Furthermore around 75% of all patients with a coarctation of the aorta have a bicuspid aortic valve. | |||
The development of coarctation aorta depends on genetic as well on non-genetic factors. Parents with coarctation aorta have a 2% (male) or 4% (female) chance of passing this defect to their child. | |||
=== Pathophysiology === | |||
Coarctation aorta has no hemodynamic consequences in utero, because only 10% of the total cardiac output crosses from the ascending to the descending aorta. However after birth the ductus arteriosus and foramen ovale close, leading the whole cardiac output through the narrowed aortic segment. This leads to an increase in resistance in the left ventricular outflow tract, resulting in an elevated systolic pressure in the left ventricle and upper extremities. When coping with the elevated pressures, the left ventricle will become hypertrophic. | |||
If the coarctation is severe or in the acute phase (after birth when the ductus is closed), systolic dysfunction of the left ventricle and heart failure can occur. | |||
Most adult patients are asymptomatic unless severe hypertension is present leading to headache, epistaxis, heart failure, or aortic dissection. In addition, claudication may occur due to reduced flow to the lower extremities. | |||
=== Evaluation === | |||
Coarctation of the aorta is easily diagnosed without invasive methods, by means of physical examination, echocardiography or MRI. The combination of weak or absent femoral arterial pulses and upper body hypertension in physical examination points into the direction of coarctation of the aorta. Nevertheless, studies have shown that the diagnosis in hypertensive patients is often missed by the referring doctor. As a consequence, a significant number of asymptomatic subjects with aortic coarctation are probably not detected until adult life, so their incidence at birth is likely to be underestimated. Late detection of subjects with aortic coarctation can have detrimental effects on survival. For, without correction, the mean life expectancy of patients with aortic coarctation is 35 years and 90% of those patients die before reaching the age of 50 years. | |||
Chest radiograph varies with age and severity of the coarctation. In infants with heart failure, the chest radiograph shows generalized cardiomegaly with increased pulmonary vascular markings due to pulmonary venous congestion. In older children and adults, the heart size may be normal but notching of the posterior one-third of the third to eighth ribs due to erosion by the large collateral arteries might be present. | |||
Transthoracic echocardiography, including suprasternal notch views, is useful for initial imaging and hemodynamic evaluation in suspected aortic coarctation. Echocardiographic evaluation should also include measurement of the dimensions of the aortic annulus, aortic sinuses, sinotubular ridge, and ascending aorta; identification of aortic valve anatomy; determination of left ventricular size and function; and identification of any potential associated lesions such as ventricular septal defect, subvalvular aortic stenosis and mitral valve deformity. | |||
=== Treatment and outcome === | |||
Since surgical repair of aortic coarctation became available in 1944, survival of patients with aortic coarctation has dramatically improved and the number of patients who were operated on and reach adulthood is steadily increasing. However, life expectancy is still not as normal as in unaffected peers. Survival of patients operated at a median age of 16 years | |||
was 91% at 10 years, 84% at 20 years and 72% at 30 years after operation. Survival of post-coarctectomy patients is significantly affected by age at operation and nowadays | |||
early repair is advocated. Even after early repair—before the age of 5 years—the estimated survival is still reduced, with 91% of the operated patients alive at 20 years and 80% at 40 to 50 years after surgery. However, repair of aortic coarctation is still recommended in patients at older age when diagnosis is delayed, because it improves blood pressure regulation and is probably associated with a lower risk of cardiovascular events in later years and improved survival. | |||
Since surgical repair of aortic coarctation became available in 1944, survival of patients with aortic coarctation has dramatically improved and the number of patients who were operated on and reach adulthood is steadily increasing. However, life expectancy is still not as normal as in unaffected peers. Survival of patients operated at a median age of 16 years | |||
was 91% at 10 years, 84% at 20 years and 72% at 30 years after operation. Survival of post-coarctectomy patients is significantly affected by age at operation and nowadays | |||
early repair is advocated. Even after early repair—before the age of 5 years—the estimated survival is still reduced, with 91% of the operated patients alive at 20 years and 80% at 40 to 50 years after surgery. However, repair of aortic coarctation is still recommended in patients at older age when diagnosis is delayed, because it improves blood pressure regulation and is probably associated with a lower risk of cardiovascular events in later years and improved survival. | |||
Transcatheter interventions for native aortic coarctation have been used for over 20 years. Transcatheter treatment for native aortic coarctation has been shown to be feasible, relatively safe and effective at short term and intermediate follow-up and is rapidly becoming the treatment of choice. Older age, however, seems to be a risk factor for suboptimal outcome after balloon angioplasty possibly due to a more fibrotic and rigid aorta. Especially in the full grown patient, stent placement seems a particularly attractive option, resulting in an almost complete relief of the gradient in 95% of the patients. Another benefit of stent placement is the ability to address longer segment coarctations, which typically have a poorer outcome after balloon angioplasty alone. Long-term results, however, are to be awaited. Concern after surgery or catheter intervention falls chiefly in seven categories: recoarctation, aortic aneurysm formation or aortic dissection, coexisting bicuspid aortic valve, endocarditis, premature coronary atherosclerosis, cerebrovascular accidents and systemic hypertension. |
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