Heart 7

oelomar's version from 2016-05-06 10:57


Question Answer
What is the “ductus arteriosus”, and what does it become upon closure at birth?A blood vessel connecting the pulmonary artery to the proximal descending aorta. It shunts deoxygenated blood. It allows most of the blood from the right ventricle to bypass the foetus’ fluid-filled non-functioning lungs. Upon closure at birth, it becomes the ligamentum arteriosum.
What is the “ductus venosus”, and what does it become upon closure at birth?In conjunction with other foetal shunts, it plays a critical role in preferentially shunting oxygenated blood to the foetal brain. It shunts a portion of the left umbilical vein blood flow directly to the IVC, thereby allowing oxygenated blood from the placenta to bypass the liver. Upon closure at birth, the remnant is known as ligamentum venosum.
What is the “foramen ovale”, and what does it become upon closure at birth?In the foetal heart, the foramen ovale is a connection between the right and left atria. It shunts oxygenated blood. Upon closure at birth, it forms the fossa ovalis.
At birth, when a baby takes its first breath, what series of events ensues?With the first breath, the lungs open up and pulmonary resistance decreases allowing pulmonic blood flow. This leads to an increased left atrial pressure vs right atrial pressure, leading to closure of foramen ovale (now called fossa ovalis). Increased oxygen concentration in blood after the first breath leads to decreased prostaglandins, thereby resulting in ductus arteriosus closure. Closure of the foetal shunts and changes in vascular resistance means that infant circulation now assumes normal adult flow.
What is Eisenmenger’s syndrome?Eisenmenger's syndrome is defined as the process in which a long-standing left-to-right cardiac shunt caused by a congenital heart defect (typically by a ventricular septal defect, atrial septal defect, or less commonly, patent ductus arteriosus) causes pulmonary hypertension and eventual reversal of the shunt into a cyanotic right-to-left shunt.


Question Answer
What is acyanotic congenital heart disease and what conditions does it involve?Acyanotic congenital heart lesions involve shunting of blood from the left heart to the right heart and most typically include atrial septal defect, ventricular septal defect, and patent ductus arteriosus. Acyanotic lesions always result in increased pulmonary blood flow.
What is the most common congenital heart disease?Ventricular septal defect (1:500 live births).
What is a “small (restrictive) VSD” and what are its signs/symptoms?A classification of VSD in which patients are asymptomatic. They are associated with a loud pan-systolic murmur. The majority close spontaneously by the age of 10 years.
What is a “large (non-restrictive) VSD” and what are its signs/symptoms?A classification of VSD which results in significant LA and LV dilatation (due to LV volume overload). Large defects usually present with heart failure symptoms in childhood, as well as delayed growth, and eventually lead to pulmonary hypertension and Eisenmenger’s syndrome. As pressures equalise, the murmur becomes softer.
What are the three types of atrial septal defect?Ostium premum (common in Down syndrome – located in lower part of atrial septum); ostium secundum (most common type, 75% - located in the mid-septum (fossa ovalis)); sinus venosus (located in superior part of the septum near the SVC or the inferior part of the septum near the IVC).
Most atrial septal defects do not close spontaneously. True or false?False. 80-100% close spontaneously if ASD diameter <8mm.
What are the clinical features of an ASD?Often asymptomatic in childhood. Adults with an unrepaired ASD develop symptoms of dyspnoea and exercise intolerance and may develop atrial arrhythmias. There is also a mid-systolic murmur and a widely split and fixed S2.


Question Answer
What is coarctation of the aorta?A congenital condition whereby the aorta narrows in the area where the ductus arteriosus (ligamentum arteriosum after regression) inserts.
What are the clinical features of coarctation of the aorta?Often asymptomatic for many years. Headaches and nosebleeds (due to hypertension), and claudication and cold legs (due to poor blood flow in the lower limbs) may be present. Physical examination reveals hypertension in the upper limbs, and weak, delayed (radiofemoral delay) pulses in the legs.
What is patent ductus arteriosus?A congenital heart defect wherein the ductus arteriosus fails to close after birth.
What are the signs and symptoms of a patent ductus arteriosus?If the shunt is moderate to large it will result in left heart volume overload and in some cases pulmonary hypertension and Eisenmenger’s syndrome.
How is a patent ductus arteriosus treated?Indometacin (a prostaglandin inhibitor).
What is the most common cyanotic congenital heart disease?Tetralogy of Fallot.
What is tetralogy of Fallot?Tetralogy of Fallot is a congenital heart defect which is classically understood to involve four anatomical abnormalities of the heart (although only three of them are always present), including: pulmonary infundibular stenosis (right ventricular outflow tract obstruction), overriding aorta (aorta positioned directly over a VSD instead of over the left ventricle), VSD, and right ventricular hypertrophy.
What are the signs and symptoms of tetralogy of Fallot in children?Systolic murmur along the left sternal border. Children with this condition may present with dyspnoea or fatigue, or with hypoxic episodes on exertion (Fallot’s spells), deep cyanosis, and possible syncope. These can even result in seizures, cerebrovascular events, or sudden death. A parasternal sustained heave is evident. Central cyanosis is commonly present from birth, and finger clubbing and polycythaemia are obvious after about 12 months. Growth is usually retarded.
What are the signs and symptoms of tetralogy of Fallot in adults?Systolic murmur along the left sternal border. Adults fatigue easily with dyspnoea on exertion. Erythrocytosis, secondary to chronic hypoxaemia, commonly results in thrombotic strokes. Endocarditis is common.
What does an x-ray show in a patient with tetralogy of Fallot?Boot-shaped heart.
How is tetralogy of Fallot treated?Surgical correction is preferred treatment.


Question Answer
What are “transposition of the great vessels” and “transposition of the great arteries”?Transposition of the great vessels is a group of congenital heart defects involving an abnormal spatial arrangement of any of the great vessels: superior and/or inferior venae cavae, pulmonary artery, pulmonary veins, and aorta. Congenital heart diseases involving only the primary arteries (pulmonary artery and aorta) belong to a sub-group called transposition of the great arteries.
Just after birth, how do babies present if they have transposition of the great vessels?It will present within a few hours of birth as a blue baby, as maternal/placental oxygenation is removed. 90% of patients present within a few days. However, in patients with a significant shunt (ASD and VSD or a large PDA) diagnosis may be delayed.
How is transposition of the great vessels diagnosed?Echocardiography.
Without surgical correction, what will happen in babies with transposition of the great vessels?They will die within the first few months of life.

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