Heart conditions Flashcards
What should routine examination of the newborn infant include in terms of assessing heart health?
Looking for signs of heart disease or dysmorphic features, assessing pulses and peripheral perfusion in arms and legs, palpating the precordium, listening for heart sounds and murmurs, and looking for signs of respiratory distress, heart failure, and shock.
Why is it important to assess pulses and peripheral perfusion in arms and legs during the newborn examination?
Why is it important to assess pulses and peripheral perfusion in arms and legs during the newborn examination?
What specific aspects of the heart should be assessed during the newborn examination?
What specific aspects of the heart should be assessed during the newborn examination?
What syndromes are many congenital cardiac abnormalities associated with?
Many congenital cardiac abnormalities are associated with specific syndromes.
In addition to heart health, what other conditions should be assessed for during the newborn examination?
Signs of respiratory distress, heart failure, and shock.
Why is it important to look for dysmorphic features during the newborn examination?
Many congenital cardiac abnormalities are associated with specific syndromes, which may present with dysmorphic features.
What should be done if there is doubt regarding cyanosis or lower limb pulses during the newborn examination?
Measure oxygen saturation and blood pressure in all limbs.
What is a helpful method of screening newborn infants for hypoxemia in cyanotic heart abnormalities?
Pulse oximetry.
How can pulse oximetry assist in identifying hypoxemia in newborn infants with cyanotic heart abnormalities?
By measuring oxygen saturation levels.
How might antenatal ultrasonography contribute to the detection of congenital heart defects?
Many congenital heart defects may be detected through antenatal ultrasonography.
What should be measured in all limbs if there is doubt regarding cyanosis or lower limb pulses?
Oxygen saturation and blood pressure.
Why is pulse oximetry particularly useful in screening newborns for hypoxemia?
It provides a non-invasive method for measuring oxygen saturation levels.
What is the primary cause of heart disease in newborn infants?
Congenital structural defects.
How often is heart disease in newborn infants attributed to an acquired abnormality in cardiac function and circulation?
Rarely
What is the typical etiology of heart disease in newborn infants?
Congenital structural defects.
What type of abnormality in cardiac function and circulation is uncommonly responsible for heart disease in newborns?
Acquired abnormalities.
What is the relative frequency of congenital versus acquired heart disease in newborn infants?
Congenital heart disease is much more common, whereas acquired abnormalities are rare.
Heart
disease in the newborn infant usually presents with one or more of the following:
- Asymptomatic heart murmur.
- Cyanosis.
- Gradual onset of respiratory distress and heart failure, usually after 2-3weeks.
- Sudden, catastrophic heart failure with shock.
What is an innocent or physiological murmur?
A short, soft (<3/6), short systolic murmur.
When is an innocent or physiological murmur commonly heard in newborns?
Soon after birth.
What are the typical characteristics of an innocent or physiological murmur?
It is short, soft (<3/6), and occurs during systole.
What are some common causes of an innocent or physiological murmur in newborns?
Flow through a patent ductus arteriosus (PDA), tricuspid regurgitation while pulmonary pressures are falling, and increased flow over a normal pulmonary valve due to a hyperdynamic circulation (e.g., anaemia or fever).
Do infants with an innocent or physiological murmur typically exhibit other abnormal cardiac signs?
No, they typically have no other abnormal cardiac signs.
When does an innocent or physiological murmur usually disappear in newborns?
During the first days of life.
What conditions may result in a systolic murmur heard well over both sides of the chest and back in an asymptomatic infant?
Peripheral pulmonary stenosis or a small persistent patent ductus arteriosus (PDA).
What characteristics are typical of the murmur caused by peripheral pulmonary stenosis or a small persistent PDA?
It is systolic and heard well (<3/6) over both sides of the chest and back.
Are these conditions more common in preterm infants?
Yes, both peripheral pulmonary stenosis and small persistent PDAs are common in preterm infants.
What may cause a systolic murmur to be heard over both sides of the chest and back in an asymptomatic infant?
Peripheral pulmonary stenosis or a small persistent PDA.
What is the typical presentation of an infant with a systolic murmur caused by peripheral pulmonary stenosis or a small persistent PDA?
They are usually asymptomatic.
What term describes the intensity of the murmur caused by peripheral pulmonary stenosis or a small persistent PDA?
It is heard well, typically less than 3/6 in intensity.
When does the murmur associated with a small ventricular septal defect (VSD) typically become audible in infants?
After day 2, once the pulmonary vascular resistance (PVR) falls significantly and the right heart pressure drops below that of the left heart.
What causes the systolic murmur associated with a small VSD?
A left-to-right shunt through the VSD.
Where is the systolic murmur associated with a small VSD best heard?
At the lower left sternal border.
Do most small VSDs close spontaneously with time?
Yes, most small VSDs do close spontaneously.
What complication may arise from larger VSDs in infants around 3 to 6 weeks of age?
Pulmonary overcirculation.
At what age may larger VSDs lead to pulmonary overcirculation in infants?
Around 3 to 6 weeks of age.
What is a potential presentation of acyanotic Tetralogy of Fallot in a newborn?
A loud, harsh murmur (3/6 or more) in an otherwise well acyanotic newborn.
How does adequate pulmonary blood flow affect the appearance of cyanosis in acyanotic Tetralogy of Fallot?
It prevents the appearance of obvious cyanosis.
What may occur over time as a result of right ventricular outflow obstruction in acyanotic Tetralogy of Fallot?
The obstruction may worsen as the ventricle and infundibulum hypertrophy.
What is a characteristic feature of the murmur associated with acyanotic Tetralogy of Fallot?
It is loud and harsh.
In acyanotic Tetralogy of Fallot, why does the right ventricular outflow obstruction potentially worsen over time?
Due to hypertrophy of the ventricle and infundibulum.
How does adequate pulmonary blood flow affect the presentation of cyanosis in acyanotic Tetralogy of Fallot?
It prevents obvious cyanosis from appearing.
What characteristics of a heart murmur in an infant suggest a serious heart abnormality that requires urgent investigation?
Any loud or long systolic murmur (>3/6), any diastolic murmur, or a murmur associated with signs of respiratory distress, heart failure, cyanosis, shock, or dysmorphic features.
What should be done if a <3/6 heart murmur is present in an asymptomatic infant and persists after day 3 of life?
It needs follow-up.
What characteristics of a heart murmur in an infant suggest the need for urgent investigation?
Any loud or long systolic murmur (>3/6), any diastolic murmur, or a murmur associated with signs of respiratory distress, heart failure, cyanosis, shock, or dysmorphic features.
What should be done if a <3/6 heart murmur persists beyond day 3 of life in an asymptomatic infant?
It requires follow-up.
When should a heart murmur in an asymptomatic infant be followed up?
If it persists beyond day 3 of life.
What should be done if a heart murmur is found in an infant with no symptoms but has certain characteristics?
It should be urgently investigated if it is loud or long systolic (>3/6), diastolic, or associated with specific signs such as respiratory distress, heart failure, cyanosis, shock, or dysmorphic features.
What is peripheral cyanosis commonly attributed to in newborn infants?
Peripheral cyanosis is commonly attributed to cold hands and feet or occurs shortly after birth (within 10 minutes).
What does persistent central cyanosis indicate in newborn infants?
Persistent central cyanosis indicates hypoxemia with inadequate arterial oxygen saturation and is usually due to a pulmonary or cardiac condition.
What does central cyanosis not responding to 100% oxygen suggest?
It suggests persistent pulmonary hypertension or cyanotic congenital heart disease.
What are some severe congenital heart abnormalities that may present with central cyanosis?
Many of these abnormalities start with a ‘T’.
What are important cardiac causes of cyanosis in newborn infants?
Obstructed pulmonary flow with right-to-left shunting or common mixing of deoxygenated blood from the right heart and oxygenated blood from the left heart.
What is the management approach for newborn infants presenting with central cyanosis and important cardiac causes?
Urgent referral and surgery are required for these cases.
What clinical presentation may lead to the mistaken diagnosis of congenital cyanotic heart disease?
Central cyanosis associated with persistent pulmonary hypertension
What is a characteristic feature of persistent pulmonary hypertension that helps differentiate it from congenital cyanotic heart disease?
There is often a pre- and post-ductal saturation difference of more than 7-10%.
In which population is persistent pulmonary hypertension usually seen?
It is usually seen in term infants who have suffered intrapartum hypoxia, often with meconium-stained liquor.
What is one potential cause of persistent pulmonary hypertension in newborn infants?
Intrapartum hypoxia.
What physiological phenomenon does not occur in infants with persistent pulmonary hypertension after delivery?
There is a significant fall in pulmonary vascular resistance (PVR).
What happens when pulmonary pressures exceed systemic pressures in infants with persistent pulmonary hypertension?
There is a right-to-left shunt through the ductus arteriosus and foramen ovale.
