Patent ductus arteriosus differential diagnosis

Associate Editor-In-Chief:; Keri Shafer, M.D. [mailto:kshafer@bidmc.harvard.edu] Priyamvada Singh, MBBS mailto:psingh@perfuse.org

Assistant Editor-In-Chief: Kristin Feeney, B.S. mailto:kfeeney@perfuse.org

Differential Physical Examination
Patent ductus arteriosus should be differentiated from other conditions producing continuous murmur-

*Venous hum

 * Frequently heard in children over the base of the neck, usually best on the right side.
 * Changes with position. Disappears in the supine position or with compression.
 * Louder in diastole

*Mammary Souffle

 * Heard during late pregnancy and the early postpartum period in lactating women.
 * Thought to be arterial in origin
 * Can be bilateral.
 * Is louder, peaks in systole
 * Vanishes in the upright position
 * Abolishes by local compression.

*Aorticopulmonary Window

 * It's a rare congenital opening between the aorta and the pulmonary trunk just above the aortic valve.
 * It can be associated with other abnormalities like anomalous origin of the coronary arteries from the pulmonary trunk and coarctation of the aorta.
 * The murmur is lower and more medial in location.
 * In adults is presented without a murmur and clinical features of the Eisenmenger's syndrome.

*Rupture of the Sinus of Valsalva

 * It can rupture into a cardiac chamber. Almost always arise from the right or the noncoronary cusps and rupture into the RV and RA respectively. Occasionally is acquired as a result of endocarditis. Large acute perforations tend to occur between puberty and age 30 causing severe retrosternal chest pain, dyspnea related to the large left to right shunt. The murmur is louder in a lower parasternal position. People with VSDs and sudden development of chest pain have frequently experienced rupture of a coexistent sinus of valsalva aneurysm. A rupture of the sinus of valsalva can distort or compress the coronary arteries and cause an infarction, distort the conduction system, cause AV block, distort the aortic valve, and cause AS or AI. Patients with rupture of the sinus of valsalva, should undergo surgical correction because mortality is high within a year of rupture.

*Fistulas of the coronary circulation

 * Generally a coronary artery that arises normally will communicate with the RV.
 * Occasionally drain into the pulmonary trunk.
 * The artery that forms the fistula is generally dilated, elongated, and tortuous. The left to right shunt is small.
 * It may not be recognized radiographically.
 * Patients with small fistula are generally asymptomatic. Therefore, no justification to repair it.
 * On the other hand, if the shunt is extremely large, then failure may develop in the 4th, 5th or 6th decade of life. It can be treated with ligation.

*Anomalous Origin of the Coronary Artery From the Pulmonary Trunk

 * Usually refers to the origin of the left coronary artery from the pulmonary trunk.
 * Approximately, 80 to 90% of the patients die in their first year of life due to ischemia.
 * Blood from the high pressure RCA flows to the low pressure left coronary artery and the pulmonary artery.
 * Anomalous origin of the RCA from the PA is much rarer, but these patients stand a better chance of surviving into adulthood because it isless likely to cause ischemia early in life.

*Pulmonary Arteriovenous Fistulas

 * Instead of being localized to the precordium, these murmurs are localized to the lung fields. Cyanosis is presented with a normal heart size. Seen in Rendu-Osler-Weber syndrome. A fistula causing cyanosis could be treated with lobectomy if it is confined to a single lobe.