Case 3

Discussion:

Rare lesion manifested by abnormal communications between pulmonary arteries and veins, most commonly congenital. Approximately 70% of the cases are associated with Rendu-Osler-Weber syndrome. Classified as either simple or complex. 80 to 90% of PAVM are of the simple type (single feeding segmental artery and a single draining vein). Symptoms in early life may vary from being totally absent to severe with cyanosis, congestive heart failure, and even fulminant respiratory failure. But often clinical signs develop between the fourth and sixth decades. Symptoms often correlated  with lesion size with lesion smaller than 2cm causing no or less symptoms. The most common clinical manifestation is epistaxis followed by dyspnea and hemoptysis. Serious neurologic events including transient ischemic attack, stroke, and brain abscess occur in 30 to 40% of patients. In the adult population, indications for treatment comprise three broad categories: intolerance of exercise, prevention of neurologic complications, and prevention of hemoptysis and hemothorax. Currently, enhanced helical CT with maximum intensity projection (MIP) reconstruction is used to define the architecture of the lesion and for follow-up.

References:

• Prager, R. L., K. H. Laws, and H. W. Bender Jr.. 1983. Arteriovenous fistula of the lung. Ann. Thorac. Surg. 36: 231-239.
• Dines, D. E., R. A. Arms, P. E. Bernatz, and M. R. Gomes. 1974.
• Pulmonary arteriovenous fistulas. Mayo Clin. Proc. 49: 460-465.
• Remy, J, Remy-Jardin, M, Wattinne, L, et al (1992) Pulmonary arteriovenous malformations: evaluation with CT of the chest before and after treatment. Radiology 182,809-816
• Remy, J, Remy-Jardin, M, Giraud, F, et al (1994) Angioarchitecture of pulmonary arteriovenous malformation: clinical utility of three-dimensional helical CT. Radiology 191,657-664