Age: 24 years
Gender: Female
Occupation: Housewife
Working diagnosis: Pregnancy in cyanotic heart disease
HISTORY
The patient was cyanotic at birth and in infancy, but only a limited workup was possible in her native country. She and her family were told she had “a hole in the heart” but no surgical intervention was possible. She received no cardiologic follow-up. She recalls being told that pregnancy would be safe despite her heart condition.
She immigrated to the United Kingdom at the age of 15. Though still cyanotic, she felt generally well and thus did not consult a health care provider. She then married and became pregnant. She was referred at 23 weeks’ gestation to a high-risk obstetric clinic.
Comments: It is not uncommon for unrepaired or even nonpalliated patients born in countries with limited medical care to present in adulthood without a clear diagnosis.
All female patients with ACHD should be given prepregnancy counseling after a complete medical evaluation. Patients should optimally be provided with information about how pregnancy may affect the mother and the fetus well before conception. (See Case 83 .)
Women with cyanotic heart disease and normal pulmonary artery pressure carry a moderate risk of death or other major complications during pregnancy (1%–5%) depending largely on ventricular function. The risk of fetal death increases with the degree of cyanosis. If prepregnancy maternal oxygen saturation is less than 85% the chance of a live birth is only 12%, compared to 92% if the saturation is greater than 90%. If pulmonary vascular disease is present (Eisenmenger syndrome) the risk of maternal death becomes very high (approximately 40%), and pregnancy is contraindicated.
CURRENT SYMPTOMS
The patient complained of shortness of breath increasing gradually from the beginning of her pregnancy. At presentation she could walk only 50 m on level ground and was limited to climbing one flight of stairs without stopping for rest.
She had occasional palpitations but no chest pain, lightheadedness, or ankle swelling.
NYHA class: III
Comments: Significant cardiovascular changes occur during pregnancy, including an increase in plasma and blood volume, an increase cardiac output, a reduction in systemic vascular resistance, and an increase in oxygen consumption.
Shortness of breath is common in pregnant women without heart disease. But in a patient with cyanosis, pulmonary blood flow is usually relatively fixed, whereas systemic vascular resistance falls during pregnancy. Thus an increase in right-to-left shunting may well occur, aggravating cyanosis.
PHYSICAL EXAMINATION
BP 120/60 mm Hg, HR 90 bpm, oxygen saturation 80% on room air (right hand and left foot)
Height 156 cm, weight 59 kg, BSA 1.58 m 2
Surgical scars: None
Neck veins: JVP was elevated to 6 cm above sternal angle with a normal waveform.
Lungs/chest: Chest was clear.
Heart: The heart was in a regular rhythm. There was a left parasternal lift. The first heart sound was normal, and the second heart sound was single and loud. There was a grade 2/3 ejection systolic murmur at the left sternal edge and a grade 2 high-pitched early diastolic murmur in the same area. A continuous murmur was heard in her left anterior chest.
Abdomen: No hepatomegaly
Extremities: Moderate digital clubbing was seen in both fingers and toes. High amplitude pulses of similar intensity were palpable at radial and femoral arteries.
Comments: The oxygen saturation of 80% should be compared to prepregnancy levels if available, as pregnancy usually worsens cyanosis.
If the patient has pulmonary hypertension, the single second heart sound rules out an unrestrictive VSD, transposition of the great arteries, or an aortopulmonary window, where a loud pulmonary component would be expected. In pulmonary atresia or truncus arteriosus the VSD does not cause a loud systolic heart murmur, as pressures are equal in both ventricles. If the diagnosis is truncus arteriosus, the systolic murmur in this patient could be due to either stenosis of a truncal valve or stenosis of the pulmonary artery at its origin from the ascending aorta.
The high pulse pressure and high-pitched diastolic murmur indicate an incompetent aortic valve or an incompetent truncal valve. The high-pitched diastolic murmur could also be seen in pulmonary hypertensive pulmonic regurgitation, but this would not explain the wide pulse pressure.
Since we know that no aortopulmonary shunts have been created (such as a BT shunt), a continuous murmur in the left chest may indicate blood flow to the left lung via aortopulmonary collateral arteries to lung segments without severe pulmonary hypertension, or another cause of a continuous murmur.
LABORATORY DATA
| Hemoglobin | 13.6 g/dL (9.5–12.0 in mid pregnancy) |
| Hematocrit/PCV | 38% (36–46) |
| MCV | 89 fL (83–99) |
| MCH | 31.9 pg (27–32.5) |
| Platelet count | 256 × 10 9 /L (150–400) |
| Sodium | 139 mmol/L (134–145) |
| Potassium | 4.2 mmol/L (3.5–5.2) |
| Creatinine | 0.64 mg/dL (0.6–1.2) |
| Blood urea nitrogen | 4.5 mmol/L (2.5–6.5) |
| Iron | 22.1 µmol/L (12.6–26) |
| Ferritin | 25 µg/L (20–186) |
| Transferrin saturation | 27% (20–45) |
OTHER RELEVANT LAB RESULTS
| Total protein | 58 g/L (62–82) |
| Albumin | 27 g/L (37–53) |
Fluorescence in situ hybridization test for chromosome 22 region q11.2: No evidence of deletion that would suggest DiGeorge syndrome.
Comments: Cyanosis should result in secondary erythrocytosis, which is notably absent here. One would expect physiologic adaptation to saturations of 80% to produce a hemoglobin of at least 18 g/dL to maintain adequate oxygenation. The patient did not have iron deficiency and there had been no bleeding. An alternative explanation is that during pregnancy the anticipated expansion in plasma volume has resulted in diluted hemoglobin levels, the patient’s hemoglobin being still relatively high for mid pregnancy (it normally ranges from 9.5–12 g/dL). The relatively low levels of total protein and albumin would also support this.
Several lesions, including truncus arteriosus and pulmonary atresia, are associated with DiGeorge syndrome (deletion of chromosomal segment 22q11). The inheritance of DiGeorge syndrome is autosomal dominant and therefore carries a recurrence risk of 50%. Therefore, any patient with these lesions should be offered screening before pregnancy. DiGeorge syndrome manifests as infantile hypocalcemia, thymic hypoplasia with immune deficiency, psychiatric disorders such as depression and schizophrenia, various degrees of mental retardation, and ACHD (most commonly truncus arteriosus, interrupted aortic arch, and TOF).
ELECTROCARDIOGRAM
FINDINGS
Heart rate: 90 bpm
PR interval: 152 msec
QRS axis: +65°
QRS duration: 90 msec
Sinus rhythm with normal AV conduction. High amplitude R-waves in leads V1–3 with inverted T-waves in these leads.
Comments: The high amplitude R-waves and discordant T-waves in leads V1–3 suggest RV hypertrophy. There is no RA overload or right-axis deviation. LV hypertrophy may also be present.
CHEST X-RAY
