Atrial Septal Defect


Patient presentation:
D.C., a two year old child, comes into the Pediatric ER with tachycardia (HR of 125 bpm), tachypnea (respiratory rate of 40), shortness of breath, pallor, and chest retractions. His mother looked very concerned and confused as to why her son appeared to be in so much physical distress. When the mother was asked what happened before she took him to the ER she reported that her son had been “kicking a soccer ball and running in the backyard for less than an hour and then began to breathe heavily and started to look pale. I have seen him do this before but this time I knew that I needed to take him somewhere since it has happened three times within the last week. He must have been playing outside for longer this time because he looked much paler than he has in the past, especially on his lips.”

Differential Diagnoses:
Asthma
Pneumonia
Acute bronchitis

Tests & Diagnosis:
Patient’s labs are as follows WBCs- 7,000/mm3; Hgb-12 g/dL-, Hct-37%, Platelet count-230,000 – all WNL. A chest X-ray was ordered to rule out pneumonia. In addition, urine and sputum cultures were drawn to rule out all other types of infections. The patient’s cultures and chest X-ray were all negative. Finally, an echocardiogram was ordered to rule out cardiac defects. The child’s echocardiogram showed atrial septal defect (ASD) and auscultation revealed a heart murmur. Atrial septal defect proved to be the cause of his exercise intolerance, pallor, tachycardia, and tachypnea. Atrial septal defect is a cardiac defect that can cause increased pulmonary blood flow and the increased pulmonary blood flow can cause congestive heart failure.  Atrial septal defect is a congenital defect that is present at birth and is never acquired but minor defects are sometimes undetected until patients reach adulthood. 

Atrial septal defect is an abnormal opening between the atria that allows blood to be shunted from the left atrium to the right atrium. The left atrium has higher pressure and blood flows into the lower pressure right atrium. This causes an increased flow of oxygenated blood from the left to right atrium. Atrial septal defects that have been undetected in adults for many years may cause cardiac dysrhythmias such as atrial fibrillation. Adults with ASD are at higher risk for developing heart failure, clots, pulmonary hypertension, and stroke.

Treatment & Outcome:
D.C. was given oxygen in the ER to reduce work of breathing. D.C. was later set up for an appointment with a pediatric cardiologist. The main surgical treatment for moderate to large defects is surgical patch closure (pericardial patch or Dacron® patch). Open repair with cardiopulmonary bypass is usually done before a child reaches school age. Closed heart procedures may also be done such as ASD closure with cardiac catheterization and umbrella placement.  Patients with congestive heart failure may take ACE inhibitors such as captopril, enalapril, or lisinopril. Patients with congestive heart failure may also take diuretics such as Lasix®, chlorothiazide, or spironolactone to reduce symptoms of CHF. Digoxin may also be given to patients with ASD but needs to be managed carefully due to its narrow therapeutic index. Surgery is the best way to treat atrial septal defect and reduce symptoms of congestive heart failure that may be associated with atrial septal defect. All post-operative patients receive aspirin for six months after surgery.

Case created by Deborah Cleveland, 2010.