Pediatric Cardiovascular Disorders

A 4-week-old boy is brought to the emergency department due to irritability and poor feeding that began earlier today. The mother notes he feels warm and is breathing faster than usual. On physical examination, the infant is awake but fussy. Capillary refill is 2 seconds, and peripheral pulses are strong. Vital signs are significant for a heart rate of 280/min, respiratory rate of 50/min, and blood pressure of 84/48 mm Hg. A 12-lead electrocardiogram demonstrates a regular, narrow QRS complex tachycardia with no discernible P waves. Intravenous access is successfully established. Arrange the following management steps in the most appropriate chronological sequence for this patient.

Match each pediatric clinical presentation to the most likely underlying congenital cardiovascular anomaly.

Match the following clinical presentations and diagnostic findings to their most likely underlying congenital heart defect.

During a routine assessment in the newborn nursery, a 2-day-old female infant is found to have central cyanosis that worsens when she cries. She was delivered vaginally at 39 weeks gestation following an uncomplicated pregnancy. Vital signs include a heart rate of 158/min, respiratory rate of 55/min, and blood pressure of 68/40 mm Hg in the right arm. Pulse oximetry indicates an oxygen saturation of 76% on room air. After administration of 100% supplemental oxygen for 10 minutes, her saturation marginally improves to 78%. Physical examination confirms bluish discoloration of the perioral area and mucous membranes. Cardiac auscultation reveals a normal S1, a loud and single S2, and a grade 3/6 holosystolic murmur at the left lower sternal border. An electrocardiogram demonstrates left axis deviation, small R waves in the right precordial leads, and tall P waves in lead II. Chest radiography reveals a normal cardiac size with diminished pulmonary vascular markings. Which of the following is the most likely diagnosis?

A $5$-day-old male neonate is brought to the pediatric emergency department by his parents due to extreme lethargy, poor feeding, and rapid, labored breathing that has worsened over the past $12$ hours. The infant was born at $39$ weeks gestation via an uncomplicated vaginal delivery and was discharged home on day two of life. On physical examination, the infant appears mottled and pale. His temperature is $36.4^\circ\text{C}$ ($97.5^\circ\text{F}$), heart rate is $192/\text{min}$, respiratory rate is $75/\text{min}$, and blood pressure is $68/40 \text{ mm Hg}$ in the right arm and $45/25 \text{ mm Hg}$ in the left leg. Capillary refill time is $6$ seconds. Palpation of the extremities reveals bounding right brachial pulses, but the femoral and dorsalis pedis pulses are barely palpable. Pulse oximetry on room air is $96\%$ on the right hand and $86\%$ on the right foot. Lung auscultation reveals bilateral crackles. Hepatomegaly is noted $3\text{ cm}$ below the right costal margin. An arterial blood gas analysis demonstrates a $pH$ of $7.12$, $pCO_2$ of $29 \text{ mm Hg}$, and $HCO_3^-$ of $10 \text{ mEq/L}$. Which of the following is the most appropriate initial step in the management of this patient?

A 6-hour-old male infant is evaluated in the neonatal intensive care unit for rapidly worsening cyanosis. He was born at 39 weeks gestation via an uncomplicated vaginal delivery to a 26-year-old primigravid woman. Vital signs demonstrate a heart rate of 175/min, a respiratory rate of 70/min, and blood pressures of 65/45 mm Hg in the right upper extremity and 63/45 mm Hg in the right lower extremity. Palpation of the peripheral arteries reveals symmetric, normal upstrokes in all four extremities. Pulse oximetry indicates an oxygen saturation of 62% despite the implementation of mechanical ventilation with a 1.0 fraction of inspired oxygen. Physical examination reveals a profoundly cyanotic, lethargic infant with prominent intercostal retractions. Cardiac auscultation demonstrates a single, loud second heart sound without any audible murmurs. A chest radiograph displays a narrowed superior mediastinum and a cardiac silhouette resembling an egg on a string, alongside mildly increased pulmonary vascular markings. A continuous infusion of a prostaglandin analog is initiated immediately; however, 30 minutes later, the infant's oxygen saturation remains at 64% and an arterial blood gas reveals a pH of 7.21, pCO2 of 42 mm Hg, and pO2 of 26 mm Hg. Which of the following interventions should be prioritized next for this patient?

A 4-year-old boy of East Asian descent is admitted to the pediatric ward with a 6-day history of persistent fever measuring up to $39.8^\circ\text{C}$ ($103.6^\circ\text{F}$). His parents report that he has been highly irritable and refuses to eat. On physical examination, the child is tachycardic but normotensive. He has bilateral nonexudative conjunctival injection, cracked and fissured lips, a prominent 'strawberry tongue,' and tender cervical lymphadenopathy. Erythema and edema of the dorsal hands and feet are noted, along with a polymorphous maculopapular rash over the trunk. A baseline transthoracic echocardiogram obtained upon admission shows structurally normal coronary arteries. He is diagnosed with classic Kawasaki disease.

Arrange the following management and follow-up steps in the correct chronological sequence for this patient, starting with immediate inpatient treatment and concluding with long-term outpatient preventive care.

Paramedics bring a 14-day-old infant to the emergency department due to severe lethargy, poor feeding, and mottled skin. On physical examination, the infant has a depressed level of consciousness and is in marked respiratory distress with grunting and severe subcostal retractions. Capillary refill time is 6 seconds. Vital signs show a heart rate of 195/min, respiratory rate of 75/min, and oxygen saturation of 89% on room air. Palpation of the extremities reveals bounding brachial pulses and imperceptible femoral pulses. Arterial blood gas analysis demonstrates severe uncompensated metabolic acidosis. Arrange the following clinical interventions and diagnostic steps in the most appropriate chronological sequence for managing this patient.

An $8$-week-old male infant is evaluated in the pediatric clinic for a two-week history of difficulty feeding. His parents report that he takes much longer to finish a bottle, becomes excessively sweaty during feeds, and seems to "breathe fast" constantly. He was born full-term at $39$ weeks gestation weighing $3.2\text{ kg}$. His current weight is $3.6\text{ kg}$. His temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), heart rate is $165/\text{min}$, respiratory rate is $68/\text{min}$, and blood pressure is $85/50\text{ mmHg}$. Oxygen saturation is $97\%$ on room air. Brachial and femoral pulses are equal and robust. Physical examination reveals a hyperactive precordium. Auscultation demonstrates a grade $4/6$ harsh holosystolic murmur at the left lower sternal border with a palpable thrill, and a faint mid-diastolic rumble at the cardiac apex. Lung examination reveals mild bilateral basilar crackles. The liver edge is palpated $3\text{ cm}$ below the right costal margin. Which of the following is the most appropriate next step in the management of this patient?

Match each pediatric cardiovascular clinical presentation with its most appropriate targeted therapeutic intervention.

An $11$-month-old boy is rushed to the emergency department due to a sudden episode of severe cyanosis and unresponsiveness. The parents report that the child became extremely agitated and inconsolable during a blood draw at a local clinic, after which his lips and fingers turned deep blue. He has a history of an uncorrected congenital heart defect for which he is awaiting surgical repair. On arrival, the child is lethargic. Vital signs show a heart rate of $175/\text{min}$, respiratory rate of $55/\text{min}$, and oxygen saturation of $65\%$ on room air. Physical examination reveals a harsh, grade 4/6 systolic ejection murmur at the left mid-to-upper sternal border and a single S2. The emergency physician immediately places the infant in a knee-chest position and applies $100\%$ supplemental oxygen via a non-rebreather mask. Intravenous morphine and a normal saline bolus are administered. Ten minutes later, the infant's oxygen saturation remains at $68\%$. Which of the following is the most appropriate next pharmacologic intervention and its primary physiologic mechanism in this patient?

A 9-month-old boy arrives at the emergency department accompanied by his parents after a frightening episode at home. His mother reports that while he was crying vigorously during a diaper change, his lips, hands, and feet suddenly turned a deep blue color, and he appeared unusually limp. The mother instinctively held him tightly with his knees tucked against his chest, and his normal skin color slowly returned over 15 minutes. The infant was diagnosed with a heart murmur in the neonatal nursery but missed his scheduled cardiology follow-up. Current vital signs are temperature 37.0°C (98.6°F), heart rate 138/min, respiratory rate 32/min, and blood pressure 94/56 mm Hg. Oxygen saturation is 93% on room air. Cardiac auscultation reveals a prominent right ventricular heave, a single S2, and a grade 3/6 harsh, crescendo-decrescendo systolic murmur heard best at the left mid-to-upper sternal border. The remainder of the physical examination is unremarkable. If a similar hypercyanotic episode occurs during evaluation and fails to improve with supplemental oxygen and knee-chest positioning, which of the following is the most appropriate next pharmacologic step in management?

A 9-month-old infant with a known, uncorrected congenital cardiac anomaly is evaluated in the pediatric triage area. His father reports that after waking up from a nap and crying vigorously, the infant's skin became notably dusky and he stopped responding to his name. Triage vital signs show a heart rate of 170/min and an oxygen saturation of 65% on room air. A harsh, crescendo-decrescendo systolic ejection murmur is prominent at the left upper sternal border. The child is currently extremely agitated, inconsolable, and tachypneic.

Arrange the following interventions in the correct chronological sequence for managing this patient's acute presentation, starting with the initial non-invasive bedside action and progressing to escalating pharmacologic steps for refractory symptoms.

A term female neonate, born at 39 weeks gestation via uncomplicated vaginal delivery, is evaluated in the nursery at 6 hours of life due to worsening central cyanosis. Her oxygen saturation is $68\%$ on room air. After receiving $100\%$ supplemental oxygen via hood for 15 minutes, her oxygen saturation only increases to $70\%$. Physical examination reveals a respiratory rate of $62/\text{min}$, equal and strong pulses in all four extremities, a prominent right ventricular impulse, and a loud, single second heart sound ($S_2$) without an appreciable murmur. Assuming the patient is ultimately found to have inadequate interatrial mixing upon diagnostic evaluation, arrange the following management steps in the most appropriate chronological sequence from initial emergency intervention to definitive treatment.

A 4-month-old girl with trisomy 21 is evaluated in the pediatric clinic for poor feeding, diaphoresis during feeds, and inadequate weight gain over the past month. The mother reports that the infant has been breathing rapidly and occasionally wheezing. Temperature is 37.1°C (98.8°F), heart rate is 165/min, and respiratory rate is 65/min. Oxygen saturation is 95% on room air. Physical examination reveals a hyperactive precordium. Auscultation demonstrates a loud first heart sound (S1), a fixed and widely split second heart sound (S2), and a grade 3/6 holosystolic murmur best heard at the cardiac apex. A mid-diastolic rumble is also auscultated at the lower left sternal border. Lung auscultation reveals bilateral crackles and diffuse expiratory wheezing. The liver edge is palpable 3 cm below the right costal margin. Which of the following is the most likely underlying cause of this patient's current symptoms?

Match each clinical presentation of a pediatric genetic syndrome to its most strongly associated congenital heart defect.

A 1-day-old male neonate is evaluated in the nursery for persistent central cyanosis. He was born at 39 weeks gestation via uncomplicated vaginal delivery to a 28-year-old primigravida. His mother had limited prenatal care but reports taking no medications during pregnancy. On examination, the infant appears comfortable but is notably cyanotic. Vital signs show a heart rate of 155/min, respiratory rate of 55/min, and oxygen saturation of 74% on room air. The cyanosis does not improve with the administration of 100% oxygen via hood. Cardiovascular examination reveals a loud, single second heart sound (S2) and a grade 3/6 holosystolic murmur at the left lower sternal border. Lungs are clear to auscultation. An electrocardiogram (ECG) demonstrates left axis deviation and tall, peaked P waves, with absent R waves in the right precordial leads. Chest radiography shows decreased pulmonary vascular markings and a normal heart size. Which of the following is the most likely diagnosis?

A 3-week-old female infant is brought to the emergency department by her parents due to poor feeding, extreme fussiness, and rapid breathing for the past 6 hours. Her vital signs are heart rate 265/min, respiratory rate 50/min, blood pressure 78/45 mm Hg, and oxygen saturation 97% on room air. Physical examination reveals a well-perfused infant with brisk capillary refill (less than 2 seconds) and normal peripheral pulses. An electrocardiogram demonstrates a regular, narrow-complex tachycardia with no discernible P waves.

Arrange the following interventions in the most appropriate sequence for managing this patient's condition, from the initial step to subsequent refractory therapies.

A 15-year-old boy, who recently immigrated, presents to the clinic with progressive shortness of breath, generalized cyanosis, and digital clubbing. His parents report that he was diagnosed with a "hole in his heart" as an infant but never received surgical treatment due to limited medical access. Physical examination reveals a loud P2 but no significant murmur. He is diagnosed with Eisenmenger syndrome secondary to a large, unrestrictive ventricular septal defect (VSD). Arrange the following pathophysiological events in the correct chronological sequence that led to this patient's current clinical presentation, starting from the neonatal period.

Parents bring their 5-week-old male infant to the outpatient pediatric clinic due to prolonged feeding times and unusual sweating. Over the past week, the mother noticed that the infant takes up to an hour to consume 2 ounces of formula, frequently pausing to catch his breath, and his forehead becomes drenched in sweat. The pregnancy and term delivery were uncomplicated, and neonatal examinations were previously documented as normal. Current vital signs include a temperature of 37.0°C (98.6°F), a heart rate of 168/min, a respiratory rate of 68/min, and an oxygen saturation of 98% on ambient air. Physical examination shows subcostal retractions and a hyperactive precordium. A grade III/VI harsh, blowing holosystolic murmur is best heard at the left lower sternal border. Palpation of the abdomen reveals hepatomegaly, with the liver edge extending 4 cm below the right costal margin. Fine crackles are audible bilaterally. Which of the following best explains the timing of this patient's symptomatic presentation?