Age: 30 years
Gender: Female
Occupation: Mother
Working diagnosis: Atrioventricular septal defect
HISTORY
As a child, the patient was diagnosed with a partial AVSD (ostium primum ASD). Corrective surgery was performed at the age of 8 years. The left AV valve was repaired and the interatrial communication was closed with autologous pericardium. She was followed up intermittently and remained well.
At the age of 27, the patient underwent a successful pregnancy. Following the pregnancy, however, she became aware of increasing shortness of breath on exertion and occasional palpitations. She was first seen in a specialist cardiology clinic 10 months postpartum. At that time she had become increasingly breathless with moderate exertion. She lived in a first-floor apartment and struggled with the stairs, especially when carrying her son.
A transthoracic echocardiogram showed moderate left atrioventricular valve regurgitation (LAVVR) through the commissure between the superior and inferior bridging leaflets. There was dilatation of the LA and LV. Transesophageal echocardiography confirmed the anatomic findings but also showed that the superior bridging leaflet of the left AV valve was thickened and had a rolled edge. The degree of LAVVR was judged as moderate to severe.
The patient noted increasing difficulty keeping up with her new motherhood role. The initial view was that she should be considered for surgical intervention. The patient expressed a desire to have additional children but was advised not to consider a further pregnancy until after her LAVVR had been re-repaired.
When the patient’s case was discussed at a multidisciplinary care conference, concerns were raised that the valve may not be repairable. It was suggested that intensive medical management through a second planned pregnancy may be a better alternative to risking either a bioprosthetic mitral valve replacement (with inevitable re-replacement) or a mechanical prosthesis requiring anticoagulation.
To help confirm the indications for surgery and safety of pregnancy, the group recommended a cardiopulmonary exercise test, a cardiac MR study to reassess the severity of regurgitation and its impact on the LV, and 24-hour ECG monitoring as it was unclear from her standard 12 lead electrocardiogram whether her rhythm was sinus or junctional. In the interim, she was started on an ACE inhibitor (not to be taken when attempting to become pregnant) and a diuretic.
A few months later, the patient had an unplanned pregnancy, despite being on the oral contraceptive pill. This created a great deal of anxiety, as her recollection of the pregnancy advice was that she would place herself at considerable risks with pregnancy. The patient chose to have the pregnancy terminated.
The patient was not seen for 18 months, having missed several appointments. When she returned to the clinic at age 30 years, she reported a further deterioration in her symptoms.
Comments: Failure to address clefts in the left AV valve at the time of closure of a partial AVSD is an important cause of late AV valve regurgitation. In the past, it was believed that the left AV valve in AVSD should be operated in a trifoliate fashion. It appears, however, that most surgeons today would close the apposition between the bridging leaflets of the left AV valve, thus leading to improving overall results. This argument, however, is not universally accepted.
Although many women may complain of fatigue or breathlessness through pregnancy and in caring for a newborn, such complaints in patients with congenital heart disease should prompt a careful cardiovascular assessment and workup.
The pathogenesis of valve dysfunction must be carefully studied to determine the etiology, as the etiology influences the decision to recommend surgery. Regurgitation may be due to acquired pathology rather than the original congenital abnormality. If the regurgitation relates to a persisting cleft in the valve, it is also important to assess the size of the mural leaflet and the size of the left AV valve orifice (which may have been restricted by the previous repair or dilated by the volume loading of the ventricle). These factors help determine whether valve repair is feasible and influence the choice of the method of repair. In the literature, late reoperation for LAVVR was around 10% or even higher.
Primary repair of a cleft left AV valve is almost always successful, particularly if there is a well-formed mural leaflet. The results of re-repair, however, are less predictable and the possibility of iatrogenic left AV valve stenosis is greater.
Further testing could be seen as simply a stalling tactic for a difficult clinical situation, but coupled with additional time, it can help clarify what the optimal management should be. The appropriate medical management of LAVVR is unclear. Afterload reduction may reduce the regurgitant fraction, and ACE inhibition has been shown to improve the functional class of patients with mitral regurgitation. However, this patient was normotensive and almost certainly had a normal systemic vascular resistance. The consequences of inducing abnormally low afterload have not been established. Similarly, in the absence of physical signs of congestive heart failure, the potential benefit of diuretics is likely to be limited.
The implications of congenital heart disease for pregnancy and thus contraception are critically important for all female adult congenital heart disease (CHD) patients of childbearing age, as shown repeatedly in this book. The cardiologist should not disregard the responsibility of discussing pregnancy and contraception clearly and openly with female patients, nor assume that such discussions have taken place with other health care providers.
CURRENT SYMPTOMS
The patient’s main complaint was shortness of breath on exertion. She was now able to manage only 10 steps on stairs. She also described occasional palpitations, which were associated with dizziness. However, she denied orthopnea, nocturnal dyspnea, ankle swelling, and chest pain.
NYHA class: II
PHYSICAL EXAMINATION
BP 130/80 mm Hg, HR 74 bpm, oxygen saturation 98%
Height 183 cm, weight 89.0 kg, BSA 2.13 m 2
Surgical scars: Previous median sternotomy
Neck veins: Jugular venous pressure was not elevated.
Lungs/chest: Lungs were clear to auscultation.
Heart: The rhythm was regular. The first heart sound was normal. There was an accentuated pulmonary component of the second heart sound. There was a third heart sound. A loud pan-systolic murmur was present at the apex, radiating to the back and axilla. There was no diastolic rumble.
Abdomen: The abdomen was soft, and the liver was not enlarged.
Extremities: No peripheral edema was present.
Comments: LV enlargement on echocardiography cannot always be demonstrated clinically. Accentuation of the pulmonary component of the second heart sound suggests a degree of pulmonary hypertension, which would be consistent with chronic, severe LAVVR. This is a clinically important sign, especially if accompanied by a prominent a-wave in the JVP, an RV heave, or signs of tricuspid regurgitation. The patient does not show any signs of congestive heart failure at present.
LABORATORY DATA
| Hemoglobin | 12.6 g/dL (11.5–15.0) |
| Hematocrit/PCV | 37% (36–46) |
| MCV | 83 fL (83–99) |
| Platelet count | 246 × 10 9 /L (150–400) |
| Sodium | 139 mmol/L (134–145) |
| Potassium | 4.0 mmol/L (3.5–5.2) |
| Creatinine | 0.62 mg/dL (0.6–1.2) |
| Blood urea nitrogen | 3.6 mmol/L (2.5–6.5) |
Comments: No significant abnormalities apart from possible borderline iron deficiency (borderline microcytosis).
ELECTROCARDIOGRAM
FINDINGS
Heart rate: 73 bpm
QRS axis: −7°
QRS duration: 96 msec
Sinus rhythm, atrial premature beats, and a superior (leftward) axis as expected.
Comments: Nonspecific T-wave inversions are seen.
FINDINGS
Overall sinus rhythm. Episodes of ectopic atrial rhythm with atrial reentry and also fibrillation. Occasional episodes of accelerated junctional rhythm. Ventricular rates between 78 and 189 bpm.
CHEST X-RAY
FINDINGS
Cardiothoracic ratio: 50%
No overt left heart chamber enlargement or evidence of congestive cardiac failure seen. Mild cardiomegaly.
