Transthoracic Echocardiography for Diagnosis of Right Pulmonary Artery to Left Atrial Fistula

Abstract

Right pulmonary artery to left atrial fistula (RPA-LAF) is a rare cardiovascular anomaly. There were no systematic and detail represent by echocardiography. We chose the patients who diagnosed with RPA-LAF at Fuwai Hospital from 2000 to 2010. All patients underwent clinical examination, chest roentgenogram, laboratory testing, electrocardiography, transthoracic echocardiography (TTE), contrast echocardiography, and cardiac catheterization. In this article, we summarize the characteristics of the TTE for diagnosing the rare cardiovascular anomaly of RPA-LAF. We undertook a detailed review of their TTE and contrast echocardiography findings to determine the characteristic findings of this condition.

Fistula between the right pulmonary artery and the left atrium coexisting with a secundum‐type atrial septal defect: An unusual case of cyanosis in a girl

“…A CT pulmonary angiogram with three-dimensional reconstruction was acquired for this case and showed a large pulmonary arteriovenous fistula that directly communicated In recent years, angiographic intervention has been successfully performed in many cases RPA-to-LA fistulas and appears to be a safe and effective alternative to surgical treatment. 6,9,12,14…”

“…Symptoms depend on the size and location of the fistula. According to literature reports, patients with large right‐to‐left shunt may have severe cyanosis in neonatal period and need to early intervention; if the right‐to‐left shunt volume is small and hypoxemia is not serious, symptoms may occur in childhood, adolescence or even in adulthood, and the symptoms are relatively mild . In addition, the lung loses its filtering function because RPA‐to‐LA fistulas bypass the capillary bed.…”

“…However, an additional fistulous channel connects the RPA to the and hypoxemia is not serious, symptoms may occur in childhood, adolescence or even in adulthood, and the symptoms are relatively mild. 12 In addition, the lung loses its filtering function because RPA-to-LA fistulas bypass the capillary bed. This characteristic allows emboli and bacteria to directly pass into the systemic circulation.…”

Can TTE Diagnose Right Pulmonary Artery‐to‐Left Atrial Fistula? A Rare Case Report and Literature Review

“…Thus, it is important to visualize the PA branch clearly from multiple views, such as short‐axis view of the aorta and some nonstandard views, including the high pulmonary artery long‐axis view. In particular, if the left PA is covered by an abnormally widened right PA, then the fistula maybe diagnosed incorrectly as an anomalous origin of the left PA. To distinguish the other end of the fistula, intra‐cardiac ultrasound contrast is also useful in cases of an absence of an unusual diversion, and microbubbles may appear in the PA and LA simultaneously after injection of saline through the fistula that connects both arteries …”

“…In particular, if the left PA is covered by an abnormally widened right PA, then the fistula maybe diagnosed incorrectly as an anomalous origin of the left PA. To distinguish the other end of the fistula, intra-cardiac ultrasound contrast is also useful in cases of an absence of an unusual diversion, and microbubbles may appear in the PA and LA simultaneously after injection of saline through the fistula that connects both arteries. 8 Based on the relationships between the fistula and the pulmonary vein (PV), Nelson and Ohara in the 1970s classified PA-LAF into four types 9,10 : type I, normal PV pattern; type II, there is an absence of the right inferior PV and fistula connected to its ostium; type III, four PVs are all connected to the fistula; and type IV, the right inferior PV is replaced by three small veins and connected to the fistula, and the left PVs are directly joined to the LA (Fig. 3).…”