Present the clinical features and emergency management of cardiovascular disorders, including: Recognize congenital and acquired heart disease. Outline management of ductal dependent lesions. Identify patients with myocarditis.
Rapid cardiopulmonary assessment to recognize and manage life-threatening illness caused by heart disease. Understand the physiology of different conditions to optimize treatment plans.
Dysrhythmias can cause serious cardiovascular compromise. Structural congenital heart disease can present in many different ways at many different ages. Acquired heart disease can be subtle yet life-threatening.
A 10-day-old infant is brought to ED by his mother for rapid breathing and not eating well. The child was a product of normal spontaneous vaginal delivery, and spent 2 days with mother in the hospital. He had an uneventful course, including circumcision. Birth weight was 3.2 kg.
The child was slow to breastfeed since birth. He would gasp and cry after sucking for a short time. Difficulty feeding. He had 3 to 4 wet diapers per day. There was no congestion or fever. He had no vomiting with feedings. He had two yellow seedy stools since passing meconium after birth.
The PAT is as follows: A: Appearance: Abnormal. Fussy, pale with central cyanosis, sweaty. B: Work of Breathing: Abnormal. Weak cry, tachypnic, rales, grunting, nasal flaring. C: Circulation to the Skin: Abnormal. Tachyardic, gallop rhythm, weak pulses. The child is ill-appearing, in respiratory distress, fussy, and has a weak cry. Additionally, there is n asal flaring and occasional grunting. The child is pale, cyanotic centrally and in all extremities, and sweaty to touch. The patient’s vital signs are as follows: Heart rate: 170 bpm Respiratory rate: 70 breaths/min Blood pressure: 82/40 mm Hg Temperature: 37 °C (rectal) Weight: 3.4 kg Oxygen saturation: 90% on room air
A: Airway: No evidence of obstruction. B: Breathing: Elevated respiratory rate and labored. C: Circulation: Pale, diaphoretic, tachycardia, weak pulse, cyanosis. D: Disability: Glasgow Coma Scale (GCS) grossly normal but in distress and inconsolable. E: Exposure: No signs of head injury, fractures, or bruising.
Lung sounds equal bilaterally with rales in both bases. Hyperactive precordium with a gallop rhythm. Pulses weak in distal and lower extremities. Distended abdomen with liver palpable 4 cm below right costal margin.
Ask the audience to characterize the patient’s condition as one of the following: Stable Respiratory Distress Respiratory Failure Shock Primary CNS Dysfunction Cardiopulmonary Failure/Arrest
Infant is in impending cardiopulmonary failure (compensated shock): Appearance, work of breathing, and circulation are abnormal, indicating cardiopulmonary failure. What are your initial management priorities?
ABCs. Give 15L oxygen by nonrebreather mask or 100% oxygen by bag-mask ventilation (BMV), or perform endotracheal intubation. Start an IV and obtain blood glucose. Perform an ECG and monitor rhythm on cardiac monitor. Get a chest radiograph. Administer fluid challenge: 10 cc/kg NS to support circulation in shock.
Administer prostaglandin E 1 (PGE 1 ) at 0.05 to 0.1 mcg/kg/min. Intubate to protect against apnea and relieve stress from work of breathing. Consider furosemide (0.5 to 1 mg/kg) if patient has not responded to initial therapy. Do a sepsis work-up and then give antibiotics. Defer lumbar puncture if the infant continues to be in respiratory distress and is unstable from cardiovascular compromise.
Consult Cardiology or transfer to pediatric cardiology center emergently. Perform an echocardiogram. If blood pressure and perfusion do not improve, add an inotropic agent, such as: Dobutamine: 2 to 20 mcg/kg/min Epinephrine: 0.1 to 1.5 mcg/kg/min
This infant is in congestive heart failure (CHF): Poor feeding and easy fatigability Gallop rhythm and enlarged liver Diminished pulses The infant is in shock, showing altered mental status and compensated shock (tachycardia, diaphoresis, respiratory distress, and normal blood pressure in upper extremities).
The infant has a possible ductal dependent lesion: Right age for presentation of shock triggered by closure of the ductus arteriosus Measure blood pressure in four extremities. Assess oxygenation response to supplemental oxygen.
There are several possible etiologies of this infant’s condition – these will be outlined in Version 1 on this slide and Version 2 on following slide. A blood pressure differential is noted in the lower extremities. Oxygenation improves to 99% with supplemental oxygen. A chest radiograph shows cardiomegaly and pulmonary edema. An echocardiogram demonstrates coarctation of the aorta. The infant improves with PGE 1 infusion, diuretics, and inotropes.
Version 2: Oxygenation fails to improve with supplemental oxygen (remains 90%). Oxygenation declines further to <80%. The chest radiograph is nonspecific. An echocardiogram demonstrates transposition of the great vessels. The infant improves with PGE 1 infusion. Surgical intervention is scheduled.
Congenital heart disease is present in 5 to 8 cases per 1,000 live births. Children with congenital anomaly usually do not show cardiovascular problems in utero. Changes at birth place great stress on infant’s cardiovascular system. Some cyanotic heart conditions are highly dependent on shunting through the ductus arteriosus. Closure can be a terminal event.
The first clues include: Age – First weeks of life, consider ductal dependent lesions; CHF usually in first months of life but may occur with acquired heart disease at any age. Progressive deterioration (mild) followed by suddenly progressing to critical condition Cyanosis Congestive heart failure Consider if concurrent sepsis is present.
Radiological studies should include: Pulmonary hypoperfusion: pulmonic stenosis, tetralogy of Fallot (TOF), tricuspid atresia (TA) Congestive heart failure (if large ventricular septal defect (VSD) is present to allow high-output failure, e.g., increased right-sided flow) Some classic chest radiograph appearances (more classic if condition is permitted to worsen): Transposition of the great arteries (TGA): Egg on side Total anomalous pulmonary venous return (TAPVR): Snowman TOF: Boot shaped
An ECG may show: Right axis (RVH): Normal for newborns Left axis: Hypoplastic right heart, tricuspid atresia, endocardial cushion defect (AV canal) ST-T changes, strain, ischemia Dysrhythmia Prolonged QT Low voltage
Laboratory studies should include: Glucose: Any child in distress needs to have hypoglycemia excluded CBC: Look for anemia, signs of sepsis Electrolytes: Congenital adrenal hyperplasia, salt-wasting form Arterial blood gas: Hyperoxia test
In the normal fetal circulation, oxygenated blood returns from the placenta via the ductus venosus, mixing with some systemic venous return blood in the inferior vena cava. Oxygenated blood preferentially shunts across the foramen ovale (FO) to the left atrium (LA). The left ventricle ejects the most oxygenated blood to the carotids and coronaries.
The right ventricle (RV) pumps less oxygenated blood into the pulmonary artery (PA). The pulmonary vascular bed is vasoconstricted, so most of the blood is shunted through the ductus arterious to mix with the systemic arterial circulation in the descending aorta (distal to the coronary and carotid arteries), thus delivering less oxygenated blood to the rest of the systemic arterial circulation.
This slide shows angiographic imaging of a coarctation in the descending aorta.
This slide shows cardiomegaly and congestive heart failure (hepatomegaly) secondary to coarctation of the aorta.
Transposition of the great arteries (TGA) is also known as transposition of the great vessels (TGV). The right ventricle pumps deoxygenated blood into the aorta, while the left ventricle pumps oxygenated blood into the pulmonary artery. A shunt between the left and right circulations is required to maintain sufficient oxygenation. In the diagram, a ventricular septal defect (VSD) permits mixing between the left and right ventricles to permit some oxygenated blood from the lungs to reach the systemic circulation. Without a VSD, the ductus arteriosus must remain patent to maintain sufficient oxygenation. Once the ductus closes, oxygenation will markedly decline. Ductus patency can be maintained with a prostaglandin E 1 infusion.
Differential diagnoses include: Other cyanotic and acyanotic congenital structural heart disease Ductal dependent coarctation Hypothermia Sepsis TORCH – Group of infections that can lead to birth defects including congenital heart disease. Includes toxoplasmosis, rubella, cytomegalovirus (CMV) and herpes simplex.
Differential diagnoses include these as well: CAH (congenital adrenal hyperplasia) Hypoglycemia Shaken baby syndrome/intracranial lesion Catastrophic gastrointestinal process, e.g., volvulus
Normal cardiovascular system (CVS) function in pediatric patients is represented by normal vital signs (next slide) and oxygen saturation, as well as the overall appearance of the child. A normal cardiac output is required to meet the body’s needs; it is defined as the amount of blood that the heart pumps each minute and is calculated using a combination of heart rate and ventricular stroke volume. Many physiological parameters such as the heart rate, stroke volume, mean arterial blood pressure, and vascular resistance affect the cardiac output. Stroke volume is the quantity of blood ejected from the heart with each contraction and is a function of the pumping action of the ventricle, which is dependent on preload, afterload, and contractility of the ventricle. Infants and young children rely mainly on the heart rate to increase cardiac output, as they have limited capacity to change stroke volume. Children older than 8 to 10 years of age develop the capacity of adults to change the stroke volume and heart rate to improve cardiac output. Oxygen delivery is the amount of oxygen delivered to the entire body per minute and is an essential component for adequate cardiac function. If the oxygen delivery falls for any reason, supplemental oxygen is required and/or the cardiac output must increase to maintain adequate oxygen delivery to the tissues. Oxygen delivery to the tissues is determined by the amount of blood flow through the lungs, the arterial oxygen content (dependent on oxygenation and hemoglobin concentration), and the cardiac output. Without adequate delivery, the metabolic demand of tissues is not met and shock (inadequate substrate delivery to meet metabolic demands) begins.
This slide shows normal vital signs for various ages.
The placental circulation is interrupted at birth, which increases the systemic arterial blood pressure. The newborn becomes hypoxic with the discontinuation of the placental flow that they relied on in utero. This causes an increase in blood pressure, heart rate, and the start of spontaneous respirations. The respirations help decrease pulmonary vascular resistance and increase the pulmonary blood flow. The pulmonary artery pressure decreases and there is an increase in pulmonary venous return and left atrial pressure, which closes the foramen ovale. Finally, the increase in systemic arterial pressure and decrease in pulmonary artery pressure cause flow through the ductus arteriosus to reverse. This initial rapid change slows down over the first 24 hours of life and pulmonary artery pressures continue to decrease toward adult levels over the next 6 weeks of life. Some of this change in pressure is aided by the anatomic structure of pulmonary vessels in the fetus and newborn, which have a thicker medial smooth muscle layer with increased vasoreactivity.
Cyanotic heart disease (CHD) results from structural and flow anomalies that developed in utero. In children with structural congenital heart disease, the changes that occur at birth and the interruption of intrauterine flow place great stress on the infant's cardiovascular system. Oxygenation is not possible for the infant who relied on the extraneous shunting (in utero) that they received from the ductus arteriosus. The normal oxygen saturation on the right side is from 70% to 75% and on the left side from 95% to 98%. The infant shunts deoxygenated blood into the systemic circulation; this is called &quot;right-to-left shunting.&quot; Some cyanotic heart disease conditions are highly dependent on shunting through the ductus arteriosus (e.g., transposition of great arteries [TGA]), in which case complete closure of the ductus is a terminal event. Cyanosis may present shortly after birth, when the ductus arteriosus begins to close.
The lesions most commonly seen that are cyanotic in presentation include the five Ts (truncus arteriosus, tetralogy of Fallot, transposition of the great vessels, tricuspid atresia, and total anomalous pulmonary venous return), severe aortic stenosis, hypoplastic left heart, and severe coarctation of the aorta.
Tetralogy of Fallot (TOF) consists of a VSD, an overriding aorta, right ventricular hypertrophy, and pulmonic stenosis. The degree of cyanosis and the severity of the TOF is largely dependent on the degree of pulmonary blood flow achieved (and hence the severity of the pulmonic stenosis). Severe pulmonary hypoperfusion results in more severe cyanosis.
Tricuspid atresia is a form of hypoplastic right heart. The right ventricle distal to the tricuspid valve is hypoplastic. Both right and left ventricles pump blood into a common outflow vessel (common trunk). Right and left mixing occurs.
The pulmonary veins drain into the right side of the heart. Right-to-left shunting occurs through an atrial septal defect (ASD), VSD, or patent ductus arteriosis (PDA).
Cyanosis as a presenting sign can be secondary to respiratory, cardiac, and hemoglobin disorders. Normal newborns will have cyanosis of the hands and feet. This is called acrocyanosis and is caused by cold stress and peripheral vasoconstriction. Generalized, or central cyanosis, is more ominous and is exacerbated by crying. The respiratory rate in children with cyanotic heart disease may not be as elevated as one would expect to see as with cyanosis caused by respiratory disorders. The baby may also have signs of shock with poor distal perfusion, cool extremities, weak cry, and a fast heart rate.
The diagram on the left demonstrates central (most of the body) cyanosis. The diagram on the right demonstrates acrocyanosis of the hands and feet (normal for newborns).
To differentiate between the causes of cyanosis, apply 100% oxygen. In infants with respiratory and hemoglobin disorders, the PaO 2 will increase significantly. The child with a cyanotic heart disease from a significant right to left shunt will have a low PaO 2 to start, which will only increase slightly with 100% oxygen because deoxygenated blood bypasses the lungs and goes directly to the left side of the heart. This dilutes the fully oxygenated blood coming from the lungs with deoxygenated blood. The oxygen saturation of the resultant mixture will never reach 100% (hence, PaO 2 will never rise significantly above 100 mm Hg despite 100% inspired oxygen). This is called the hyperoxia test and may help to distinguish cyanotic heart disease from respiratory causes, although severe respiratory illness may also result in low oxygen saturation despite the application of oxygen.
Increased pulmonary vascularity: Total anomalous pulmonary venous return Truncus arteriosus Transposition of the great arteries Other complex lesions without pulmonic stenosis Decreased pulmonary vascularity: Tetralogy of Fallot Ebstein’s anomaly Hypoplastic right heart, tricuspid atresia Complex lesions with pulmonic stenosis
Prostaglandin E 1 can be used to keep the ductus open after birth. It is infused at 0.05 to 0.1 mcg/kg/min with an increase to 0.2 mcg/kg/min over several minutes. Side effects of the infusion include apnea, pulmonary congestion, fever, hypotension, seizures, and diarrhea. The infant should be considered for elective intubation if a prostaglandin infusion is started to secure the airway in case of apnea and to decrease the work of breathing. This can add stress to an already stressed heart.
Noncyanotic congenital heart diseases may present with signs of congestive heart failure and/or heart murmurs that are heard during physical exam. They may be divided into left-to-right shunts and obstructive lesions. The left-to-right shunt lesions, which can show an increase in pulmonary circulation, include atrial septal defects, ventricular septal defects, and patent ductus arteriosus. Obstructive lesions include aortic stenosis, coarctation of the aorta, pulmonary stenosis, and mitral stenosis. Most of these patients present during the first 6 months of life when the shunt or obstruction overwhelms the cardiac compensation and function.
Clinical features include signs of congestive heart failure, such as tachypnea, tachycardia, diaphoresis, decreased feeding, hepatomegaly, various systolic flow murmurs, and gallop rhythms, depending on the specific lesion. The child may present with decreased activity or poor sleeping with respiratory distress.
Diagnostic studies include chest radiograph, ECG, and echocardiogram. The chest radiograph will show an abnormal cardiac shadow or increased pulmonary vascular flow. The ECG may show an abnormal axis, QRS changes, ST segment changes, and chamber enlargement. The definitive testing is the two-dimensional echocardiogram that will define the abnormality and the degree of congestive heart failure.
Provide supplemental oxygen and assist ventilation as needed. Elevate the head and shoulders about 45 degrees. Place cardiorespiratory and pulse oximetry monitoring Obtain IV access. Send laboratories (electrolytes, blood urea nitrogen [BUN], creatinine, complete blood count). Obtain chest radiograph and ECG. Administer furosemide, nitroglycerin, and digoxin. Administer inotropic agent for signs of shock.
A 10-year-old boy presents with the chief complaint of chest pain and shortness of breath. Previously he had 5 days of cold and cough symptoms. He has been lying around a lot and has missed 1 week of school. He is usually a very active child but complains that he is “just too tired” to play.
The PAT is as follows: A: Appearance: Abnormal. B: Work of Breathing: Abnormal. C: Circulation to the Skin: Abnormal. Vital signs include: Heart rate: 130 bpm Respiratory rate: 44 breaths/min Blood pressure: 90/65 mm Hg Temperature: 37.8°C Oxygen saturation: 90% on room air, increases to 100% on supplemental oxygen
A: Airway: Patent B: Breathing: Intermittently shallow and deep; rapid respiratory rate C: Circulation: Pale; pulse rapid, thready, and weak D: Disability: No focal deficits, GCS 15 E: Exposure: No signs of injury
O: Onset: Chest hurts for several days P: Pain: Provoked by cough and exertion; he has a hard time catching his breath whenever he gets up and walks. Q: Quality: Burning, pressure R: Region: Substernal, some radiation to shoulders S: Severity: 3-8 out of 10 T: Time: Pressure and SOB last almost all day, exacerbations with exertion last 15 to 30 minutes
Neck: Jugular venous distention supine Lungs: Diminished breath sounds with occasional end expiratory wheeze with deep breaths Cardiac: Distant heart sounds, no murmurs, S 3 gallop rhythm Abdomen: Distended with palpable spleen and liver Neurologic: No focal deficits
Ask the audience to characterize the patient’s condition as one of the following: Stable Respiratory Distress Respiratory Failure Shock Primary CNS Dysfunction Cardiopulmonary Failure/Arrest What are your initial management priorities? Immediate oxygen support Cardiac and oxygen saturation monitoring
The child is in respiratory distress and cardiogenic shock. Patient appearance includes: Thin, pleasant boy who seems tired but talks in complete sentences without difficulty. He is tachypneic with mild retractions. Slightly pale in color Dusky nail beds Overall he demonstrates normal appearance, but increased work of breathing and signs of shock.
Check ABCs. Give oxygen by nonrebreather mask. Obtain IV access. Check rhythm on cardiac monitor. Obtain blood glucose, lab studies. Consider reducing preload and afterload with nitrates. Consider diuretic therapy. He may need inotropic support.
He may have an acquired cardiac problem due to a respiratory illness during winter months causing secondary myocarditis. A second possibility is a congenital heart lesion that had been asymptomatic until this illness, such as an anomalous coronary artery or valvular disease. The child may have developed pericarditis.
Consider myocarditis in any child with: Weakness SOB Chest pain Especially if associated with preceding prodromal viral illness Distant heart sounds: “Silent Chest” Enlarged heart on chest radiograph
A chest radiograph will reveal cardiomegaly and prominent vasculature, perhaps even pulmonary edema. Laboratory studies may not add much and may be nonspecific.
Myocarditis is a global infection/inflammation of the myocardium – the degree to which each child is affected is variable. In this slide (Version 1) and the following slide (Version 2), two potential courses of the disease are described. A chest radiograph reveals cardiomegaly. The echocardiogram reveals poor cardiac contractility. The diagnosis for this patient is myocarditis. He is maintained on inotropes and pressor agents. He recovered to a point that he could be discharged 2 weeks later. Will be followed closely for years to assess the degree to which he regains cardiac function
Version 2: A chest radiograph reveals cardiomegaly. The echocardiogram reveals poor cardiac contractility. He is diagnosed with myocarditis. His condition deteriorated in the ED, and he suffered progressive shock. He required inotropic support but developed ventricular tachycardia and ventricular fibrillation. Talk students through the ventricular fibrillation algorithm. Discuss the AHA Guidelines 2000. Extracorporeal membrane oxygenation (ECMO) is a last possibility to maintain circulation until improvement or cardiac transplantation.
Inflammatory disease of the myocardium includes: Direct infection of the myocardium (e.g., viral myocarditis) Toxin production (e.g., diphtheria) Immune response as a delayed sequela of an infection (postviral or postinfectious myocarditis) A common type of myocarditis is acute rheumatic fever (ARF).
A patient must have two of the major Jones criteria, or one major plus two minor criteria of acute rheumatic fever plus documentation of an antecedent group A streptococcal infection via serology or culture. Major criteria include: Carditis: Most commonly valvulitis (mitral and aortic valve most common) diagnosed by auscultation (apical pansystolic murmur radiating to the axilla or soft diastolic murmur at the base) or echocardiography. Migratory polyarthritis Chorea Erythema marginatum Subcutaneous nodules Minor criteria include fever, elevated CRP or ESR, prolonged PR interval, and arthralgia.
Pericarditis is an acute or chronic inflammation of the pericardial sac with an increase in the pericardial fluid volume and pressure causing cardiac stroke volume reduction. Between visceral and parietal pericardium is a fluid layer to help protect the heart and its contractility. The usual fluid volume in the pericardial sac is 10 to 30 mL. When there is a sudden increase in fluid, or constriction of the pericardial sac, chamber-filling volume is restricted, which results in stroke volume reduction and hypotension (a process known as tamponade). This increases the end-diastolic pressure in the ventricle, which impairs ventricular filling and the ejection volume. The most common etiology is infectious, with approximately 30% resulting from a bacterial cause. The most common viral etiology is Coxsackie virus. Other causes include autoimmune disease, trauma, and neoplasms. The most common cause of constrictive pericarditis is tuberculosis. Other bacterial causes of pericarditis include pneumococci, staphylococci, and Haemophilus influenzae pericarditis.
Clinically, the child may present with chest pain and respiratory distress. If they have altered cardiac function from either an increase in pericardial fluid or constriction of the pericardial sac, they will present with signs of congestive heart failure as well as a precordial “knock” or rub (like the sound of shoes walking on snow). The classic signs include exercise intolerance, fatigue, jugular distension, lower extremity edema, hepatomegaly, poor distal pulses, diminished heart tones, and pulsus paradoxus.
Endocarditis, although uncommon, is increasing in incidence, mostly because children are surviving their congenital heart disease with artificial valves and patches, as well as an increased frequency of patients with central lines for various therapies. Endocarditis is an infection of the endothelial surface of the heart, with a propensity for the valves. Endocarditis may be caused by many different organisms, although 90 percent of cases are caused by gram-positive cocci. Although streptococcus (e.g., Streptococcus viridans ) is the most common organism involved, infections with Staphylococcus aureus , Streptococcus pneumoniae , or group A ß hemolytic streptococci can be more virulent.
Patients typically present with fever, tachycardia, and signs of cardiac failure or dysrhythmia with a history of recent cardiac surgery or indwelling vascular catheter. Other signs include myalgias, heart murmur or petechiae, septic emboli, or splenomegaly. They may present with signs indistinguishable from myocarditis with poor cardiac contractility and inadequate perfusion with cool extremities, or symptoms similar to pericarditis, with pain in addition to congestive heart failure.
Kawasaki disease (mucocutaneous lymph node syndrome [MLNS]) was first described by Kawasaki in 1967. The etiology is unknown, but it is seen most often in children less than 5 years of age, during the winter and spring months, and with boys more susceptible than girls. There is also a predilection for Asian and African children. These patients may present with cardiac abnormalities that present in similar manner to children with decreased myocardial contractility, myocarditis, or coronary insufficiency. The child may present or go on to develop congestive heart failure and shock with chest pain. Without treatment, 15% to 20% of children with Kawasaki disease will develop coronary artery aneurysms within 1 to 3 weeks from the onset of illness, which can eventually lead to a myocardial infarction or ischemia-induced dysrhythmias. A child that presents with a myocardial infarction may have more nonspecific findings than an adult. They can present with nausea, vomiting, and abdominal pain. They may be diaphoretic and crying, or asymptomatic.
Clinically, the child presents with a history of fever for 5 days or more. The diagnostic criteria are the presence of conjunctivitis, cervical lymphadenopathy, gingivostomatitis, maculopapular exanthem (called polymorphous, which means that it can have many different patterns), and swelling of the hands with erythema of the palms. Polymorphous rash is often maculopapular, morbilliform, or erythema multiforme-like.
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