Examples of right-to-left shunting are [[congenital cyanotic heart disease]] and [[pulmonary arteriovenous malformation]]s (PAVMs)
((Kawamata T, Takeshita M, Ishizuka N, Hori T. Patent foramen ovale as a possible risk factor for cryptogenic brain abscess: report of two cases. Neurosurgery 2001;49:204-206; discussion 206-207.))
((Sung CW, Jung JH, Lee SH, Choi S, Cho JR, Lee N, et al. Brain abscess in an adult with atrial septal defect. Clin Cardiol 2010;33:E51-E53.))
,which form the basis of current recommendations for prophylactic antibiotics in patients with such conditions and for prophylactic closure of PAVMs
((Trerotola SO, Pyeritz RE. PAVM embolization: an update. AJR Am J Roentgenol 2010;195:837-845.)).