Patent ductus arteriosus

Revision as of 14:43, 9 March 2019 by SLuckettG (talk | contribs) (Management)

Background

  • Ductus arteriosus is a blood vessel connecting main pulmonary artery to proximal descending aorta
    • Shunts blood from right ventricle to bypass fetus's non-functioning lungs in utero
  • In PDA, ductus fails to close after birth
  • Second most common congenital heart disease
  • Approximately 1 in 1600 to 5000 live births in the US.[1]

Pathophysiology

PDA.png
  • Ductus arteriosus shunts blood from the pulmonary artery to the aorta bypassing the lungs while in utero
  • Normally closes soon after birth via complex process
    • Regulated by oxygen tension and decreases in prostaglandin E2
    • Becomes ligamentum arteriosum
  • In PDA, ductus fails to close
    • Results in shunting of blood between aorta and pulmonary artery
    • Some oxygenated blood from high-pressure aorta shunts to lower pressure pulmonary artery
    • A large shunt can cause increased fluid return to lungs and increased lung pressure, leading to pulmonary hypertension
  • Some congenital heart defects, such as transposition of the great arteries, are incompatible with life 'without a PDA; may be necessary to allow oxygenated and deoxygenated blood to mix
    • In these cases prostaglandins are used to keep the ductus arteriosus open.

Clinical Features

  • Continuous machine like heart murmur
  • Differential cyanosis (cyanosis of lower extremities and not the upper extremities)
  • Dyspnea
  • Tachycardia
  • Widened pulse pressure
  • Congestive heart failure
  • Failure to thrive

Differential Diagnosis

Congenital Heart Disease Types

Evaluation

Echocardiography demonstrating PDA[3]
  • Careful physical examination demonstrating characteristic machine like murmur
  • Echocardiography
    • MRA and Cardiac CT can also be used as diagnostic tools
  • Laboratory tests usually not helpful

Management

  • Spontaneous closure common
  • If significant respiratory distress or impaired oxygen delivery, therapy usually required

Medical Therapy

  • IV indomethacin: usually effective when administered in the first 10-14 days of life.

Surgical Therapy:

  • Offered if medical therapy fails
    • Cardiac catheterization and catheter closure
    • Surgical ligation

Disposition

See Also

External Links

References

  1. Mitchell, S. C., Korones, S. B., Berendes, H. W. Congenital heart disease in 56,109 births: incidence and natural history. Circulation 43: 323-332, 1971.
  2. Knipe K et al. Cyanotic congenital heart diseases. Radiopaedia. http://radiopaedia.org/articles/cyanotic-congenital-heart-disease
  3. http://www.thepocusatlas.com/pediatrics/