Cardiac Conditions

Question 1

What is the difference between cyanotic and acyanotic congenital heart defects (CHD)?

Answer 1

Cyanotic CHD involves decreased oxygen saturation, causing blue discoloration of the lips, nails, and skin (e.g., TOF, TGA, HLHS). Acyanotic CHD involves left-to-right shunting or increased pressure, typically without cyanosis (e.g., PDA, ASD, VSD, AVSD).

Question 2

What is congenital heart disease (CHD) and how common is it?

Answer 2

CHD refers to a group of heart defects present at birth. Mild CHD occurs in up to 10 per 1000 births, while moderate to severe CHD occurs in approximately 2.5 to 3 per 1000 births. Advances in medicine have allowed 85% of infants with CHD to survive into adulthood.

Question 3

What are the most common congenital heart defects?

Answer 3

Ventricular Septal Defects (VSDs) are the most common congenital heart defects, occurring in 1 per 1000 births. Other common defects include PDA, ASD, and TOF.

Question 4

Define the terms ‘patent ductus arteriosus (PDA)’ and ‘ventricular septal defect (VSD)’.

Answer 4

Patent Ductus Arteriosus (PDA): A persistent opening between the aorta and pulmonary artery, increasing blood flow to the lungs. Ventricular Septal Defect (VSD): A hole in the septum dividing the ventricles, allowing left-to-right shunting of blood.

Question 5

What are the key stages of fetal cardiac development?

Answer 5

1. Primary cardiac tube forms the left ventricle. 2. Secondary heart field forms the right ventricle. 3. Tertiary field cells form atrial chambers and portions of ventricles. 4. Cardiac neural crest cells form the aortic arch and coronary vessels. Development is complete by 8-12 weeks gestation.

Question 6

What are the primary structures involved in fetal circulation?

Answer 6

Fetal circulation bypasses the lungs using the placenta for oxygen exchange. Key structures include the foramen ovale (between atria), ductus arteriosus (connects pulmonary artery to aorta), and ductus venosus (shunts blood from umbilical vein to inferior vena cava).

Question 7

How does fetal circulation change at birth?

Answer 7

At birth, the first breath causes the lungs to expand and pulmonary resistance to drop. Pressure increases in the left atrium, closing the foramen ovale. The ductus arteriosus and ductus venosus close as blood flow shifts to neonatal circulation.

Question 8

What are the four main components of early heart development?

Answer 8

1. Primary cardiac tube: forms the left ventricle. 2. Secondary, anterior heart field: forms the right ventricle. 3. Tertiary field cells: form atrial chambers and parts of ventricles. 4. Cardiac neural crest cells: form the aortic arch and coronary arteries.

Question 9

When is the development of the heart structurally complete during gestation?

Answer 9

The heart’s four-ventricle structure is complete by 8 weeks of gestation, and development is primarily complete between the 10th and 12th weeks of gestation.

Question 10

Why does the fetal heart not depend on the lungs for oxygenation?

Answer 10

The fetal heart bypasses the lungs due to high pulmonary resistance. Oxygen and carbon dioxide exchange occurs in the placenta, with oxygen-rich blood flowing through the heart’s chambers.

Question 11

How are congenital heart defects (CHD) classified?

Answer 11

CHD is classified by blood flow direction and oxygenation status: Acyanotic (left-to-right shunting or increased pressure, e.g., PDA, ASD, VSD) and Cyanotic (reduced oxygen saturation, e.g., TOF, TGA, HLHS).

Question 12

What are the symptoms of acyanotic CHD?

Answer 12

Symptoms include rapid breathing, delayed growth, excessive sweating, feeding difficulties, and signs of heart failure.

Question 13

What are the symptoms of cyanotic CHD?

Answer 13

Symptoms include cyanosis (blue lips, nails, toes), polycythemia (increased RBC production), increased blood viscosity, and higher risk of CVAs and microvascular issues.

Question 14

Describe the pathophysiology of Patent Ductus Arteriosus (PDA).

Answer 14

PDA occurs when the ductus arteriosus remains open after birth, causing increased blood flow to the lungs. Symptoms include rapid breathing and delayed growth. It is an acyanotic CHD.

Question 15

What is Tetralogy of Fallot (TOF), and what are its components?

Answer 15

TOF is a cyanotic CHD with four defects: 1) Large ventricular septal defect (VSD), 2) Pulmonary stenosis, 3) Overriding aorta, 4) Right ventricular hypertrophy.

Question 16

What is Hypoplastic Left Heart Syndrome (HLHS), and why is it life-threatening?

Answer 16

HLHS is a cyanotic CHD where the left ventricle is underdeveloped or absent, often with mitral/aortic valve atresia. Survival depends on keeping the ductus arteriosus open until surgery. It can lead to shock and multiorgan failure.

Question 17

What is the role of erythropoiesis in cyanotic CHD?

Answer 17

In cyanotic CHD, hypoxia stimulates erythropoiesis, increasing red blood cell production. This leads to polycythemia, increased blood viscosity, and higher risk of CVAs.

Question 18

What are the key differences between volume-related and pressure-related acyanotic CHD?

Answer 18

Volume-related CHD (e.g., PDA, ASD, VSD) involves increased blood volume to the lungs, causing left-to-right shunting. Pressure-related CHD (e.g., coarctation of the aorta, aortic/pulmonary stenosis) involves increased ventricular pressure during blood ejection.

Question 19

What is Transposition of the Great Arteries (TGA), and why is it critical?

Answer 19

In TGA, the aorta arises from the right ventricle, and the pulmonary artery arises from the left ventricle, reversing normal blood flow. This leads to deoxygenated blood circulating in the body and oxygenated blood returning to the lungs, requiring immediate surgical intervention.

Question 20

What are common surgical procedures for severe CHD?

Answer 20

Surgical interventions include the Norwood procedure, Glenn procedure, Fontan procedure, and arterial switch procedure, depending on the defect (e.g., HLHS or TGA).

Question 21

What are the three stages of surgical repair for Hypoplastic Left Heart Syndrome (HLHS)?

Answer 21

1) Blalock-Taussig shunt or Norwood procedure (first few weeks of life), 2) Bidirectional Glenn procedure (4–6 months of age), 3) Fontan procedure (3–6 years of age).

Question 22

What is the Norwood procedure, and when is it performed?

Answer 22

The Norwood procedure is the first stage of surgical repair for HLHS, performed in the first few weeks of life. It creates a functional systemic circulation by connecting the right ventricle to the aorta.

Question 23

What are the key steps in a heart transplant procedure?

Answer 23

1) Use of a bypass machine, 2) Excising the original heart, 3) Inserting the donor heart, 4) Reanastomosis of atria and great arteries. The vagus and sympathetic cardiac nerves are severed, altering heart rate control.

Question 24

What are the risks and complications following a pediatric heart transplant?

Answer 24

Risks include rejection, infection, graft-versus-host disease, higher resting heart rate, reduced heart rate response to exercise, and the need for lifelong immunosuppressive therapy.

Question 25

What is prostaglandin E used for in CHD management?

Answer 25

Prostaglandin E is used to keep the ductus arteriosus open in conditions like HLHS and TGA, allowing blood flow to bypass underdeveloped or obstructed areas until surgery can be performed.

Question 26

What is the arterial switch procedure, and for which condition is it performed?

Answer 26

The arterial switch procedure is used to correct Transposition of the Great Arteries (TGA). It restores normal blood flow by switching the origins of the pulmonary artery and aorta.

Question 27

How is coarctation of the aorta treated?

Answer 27

Treatment includes surgical repair (removal of the narrowed segment) or balloon angioplasty to widen the aorta and restore normal blood flow.

Question 28

What are the indications for pediatric heart transplantation?

Answer 28

Indications include end-stage heart disease, congenital heart defects like HLHS or DORV, severe cardiomyopathy, and a predicted survival of less than two years despite medical management.

Question 29

What physical therapy considerations are important post-heart transplant?

Answer 29

PT considerations include monitoring altered heart rate response, emphasizing warm-ups and cool-downs, addressing sternal precautions, and managing endurance through graded exercise.

Question 30

What is the Berlin Heart, and when is it used?

Answer 30

The Berlin Heart is a ventricular assist device used as a bridge to transplant for pediatric patients with severe heart failure. It supports circulation while awaiting a donor heart.

Question 31

What are the key components of a physical therapy evaluation for children with CHD?

Answer 31

1) History: Medical/surgical and developmental. 2) Lab values: CBC, arterial blood gas. 3) Appearance: Edema, coloring. 4) Vital signs: O2 saturation, heart rate. 5) Musculoskeletal/Respiratory: Strength, mobility, pectus deformities.

Question 32

What are common respiratory findings in children with CHD during evaluation?

Answer 32

Findings include tachypnea, nasal flaring, retractions, barrel chest, rib flaring, and mid-trunk folds. These indicate respiratory effort and potential complications.

Question 33

What equipment and devices are commonly used for children with CHD during PT?

Answer 33

Monitors, respiratory support devices (e.g., ventilators, CPAP), extracorporeal membrane oxygenation (ECMO), and ventricular assist devices (VAD).

Question 34

What interventions are commonly used in physical therapy for children with CHD?

Answer 34

1) Positioning and postural education. 2) Breathing exercises and airway clearance. 3) Strengthening and developmental skill training. 4) Aerobic and endurance training. 5) Scar management and caregiver education.

Question 35

Why is developmental delay common in children with CHD, and how does PT address it?

Answer 35

Developmental delay is caused by factors like brain development, genetic syndromes, strokes, seizures, and prolonged hospitalization. PT focuses on developmental skills, strength, and functional mobility to address these delays.

Question 36

What are sternal precautions, and why are they important in children with CHD?

Answer 36

Sternal precautions involve limiting lifting, pushing, pulling, and certain arm movements post-sternotomy to protect healing and reduce the risk of complications.

Question 37

How does PT address endurance and aerobic capacity in children with CHD?

Answer 37

PT includes graded aerobic exercises, monitoring vitals, emphasizing warm-ups and cool-downs, and building tolerance to physical activity over time.

Question 38

What are the long-term neurodevelopmental outcomes for children with CHD?

Answer 38

More than half of children with moderate to severe CHD experience disabilities or impairments in cognition, language, gross and fine motor skills, and quality of life. These outcomes are influenced by the severity of the defect, genetic syndromes, and timing of interventions.

Question 39

What are common quality-of-life challenges faced by children with CHD and their families?

Answer 39

Challenges include developmental delays, frequent hospitalizations, need for surgeries and medical follow-ups, emotional and psychological stress for the child and family, and limitations in physical activity.

Question 40

What are the key considerations for exercise prescription in children post-heart transplant?

Answer 40

Key considerations include: 1) Adjusted exercise intensity due to altered heart rate response. 2) Emphasis on warm-ups and cool-downs. 3) Monitoring for signs of fatigue or rejection. 4) Tailoring exercises to improve endurance and strength while avoiding excessive strain.