Age: 16 years
Gender: Female
Occupation: Student
Working diagnosis: Left-sided congenital diaphragmatic hernia
HISTORY
The patient was diagnosed antenatally with a left-sided congenital diaphagmatic hernia (CDH). She was delivered near term by elective cesarian section after an uneventful pregnancy. A cleft soft palate was noticed postnatally. Genetic studies showed a normal female karyotype.
The diaphragmatic hernia was repaired at 3 hours of age. The postoperative period was uneventful, she was weaned off the ventilator 10 days after repair, and was discharged home at the age of 3 weeks.
The cleft palate was repaired at 15 months of age followed by a pharyngoplasty at the age of 4 years. She required speech and language therapy but had no symptoms referable to the CDH in infancy and early childhood.
At the age of 16, she experienced an episode of syncope after mild exertion. She also complained of increasing fatigue. She was referred for a cardiology review.
Comments: The incidence of CDH is 1 in 5000 live births, 1 in 2000 if stillbirths are included. Defects are more common on the left side (70%–85%). Occasionally there can be a bilateral defect (5%). CDH is frequently associated with karyotypic abnormalities (34%).
The optimal timing of repair of CDH has gradually shifted from “emergency repair” after birth to a strategy of delayed repair following stabilization with either conservative ventilation strategies or even the use of extracorporeal membrane oxygenation. No substantial advantage of either approach has been proven to date.
CURRENT SYMPTOMS
The patient’s main symptom has been fatigue. Throughout her life her exercise capacity had always been less than that of her peers, but there had been a marked deterioration over the previous 6 to 8 months. She was exhausted after each school day and had little energy. She admitted having had three dizzy spells, briefly losing consciousness on one occasion.
NYHA class: II
Comments: The symptoms experienced here should alert the physician to look for evidence of PAH. Pulmonary hypertension frequently accompanies CDH repair, which is associated with a hypoplasia of alveoli and their accompanying arteries and veins.
The clinical manifestations of pulmonary hypertension can often be subtle. Exertional dyspnea and effort intolerance are common. Patients can present with syncope related to exertion or in other settings. Other symptoms include chest pain and hemoptysis.
PHYSICAL EXAMINATION
BP 100/80 mm Hg, HR 70 bpm, oxygen saturation 98% on room air
Height 152 cm, weight 39.9 kg, BSA 1.3 m 2
Neck veins: JVP was not elevated and the waveform was normal.
Lungs/chest: Chest was symmetrical. On auscultation the lungs were clear with good air entry bilaterally.
Heart: There was a mild RV heave. The pulmonary component of the second heart sound was accentuated. There were no murmurs.
Abdomen: No hepatosplenomegaly
Extremities: There was no peripheral edema, pallor, no cyanosis at rest, and no clubbing.
Neurological examination was normal.
Comments: The patient is less than 0.4 percentile for weight, and less than 9 percentile for height.
Chest symmetry is an important finding in patients with prior repair of diaphragmatic herniation. The examiner should specifically look for signs of PAH. When the pulmonary artery pressure is elevated the pulmonary component of the second heart sound is loud. An RV heave may be present, due to hypertrophy and hyperactivity of the RV. Later in the disease there may be evidence of RV failure, such as hepatomegaly and peripheral edema.
LABORATORY DATA
Hemoglobin | 12.3 g/dL (11.5–15.0) |
Hematocrit | 36% (36–46) |
MCV | 90 fL (83–99) |
MCH | 30.6 pg (27–32) |
Sodium | 140 mmol/L (134–145) |
Potassium | 3.9 mmol/L (3.5–5.2) |
Creatinine | 59 mg/dL (71–106) |
Blood urea nitrogen | 5.0 mmol/L (2.5–6.5) |
Total bilirubin | 7.0 µmol/L (0–17) |
ALT | 9 IU/L (0–31) |
Alkal. phosphatase | 66 IU/L (50–150) |
Albumin | 46 g/L (35–50) |
Thyroid function tests were within normal limits.
Comments: There were no significant abnormal findings in baseline laboratory tests.
ELECTROCARDIOGRAM
FINDINGS
Heart rate: 85 bpm
PR interval: 140 msec
QRS axis: +95°
QRS duration: 75 msec
Sinus rhythm with normal intervals. There was borderline right-axis deviation. T-wave inversions were present throughout the precordial leads without voltage evidence of either RV hypertrophy or RA overload.
Comments: In severe pulmonary hypertension, signs of RV hypertrophy are frequently seen. The P-wave amplitude may often be above 2.5 mv, consistent with RA hypertrophy. Neither one of these signs is present in our patient.
CHEST X-RAY
FINDINGS
Cardiothoracic ratio: 42%
Situs solitus, levocardia, left aortic arch.
The cardiac size was normal. The translucency of the two lungs differed. The left lung appeared overinflated and hypertranslucent. The left hemidiaphragm was flattened. The patient had scoliosis.
Comments: The abnormal left hemidiaphragm is explained by the previous history of CDH. The different opacification density of the right lung compared to the left is consistent with some degree of pulmonary hypoplasia. The pulmonary arteries are not enlarged, which would be expected in typical PAH.
EXERCISE TESTING
6-Minute Walk Test Results
Distance walked: 350 m
Pretest O 2 saturation: 98% (room air)
Posttest O 2 saturation: 96% (room air)
Exercise protocol: | Modified Bruce |
Duration (min:sec): | 7:10 |
Reason for stopping: | Dyspnea |
ECG changes: | None |