Magnitude of right-to-left shunt as the only determinant of stroke in a pair of identical twins.
Right-to-left shunt due to patent foramen ovale is a well-established risk factor for stroke in the young. The magnitude of shunt seems to be correlated to the risk of stroke in individuals. We report the cases of two 51-year-old identical twins, with similar risk factors for ischemic stroke, in which the sibling with a large and permanent shunt suffered a left hemispheric stroke and the other, with a small and latent shunt, was asymptomatic. In a three-year follow-up, the siblings were both asymptomatic, and the dimensions of shunts were unchanged. Our cases stress the importance of quantifying right-to-left shunt in order to stratify the risk of stroke in individuals, and suggest a role of heredity in patency of foramen ovale.
Del Sette
M
M
Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, Via De Toni 5, I-16132 Genoa, Italy. mdelsette@neurologia.unige.it
Rizzi
D
D
Pretta
S
S
Gandolfo
C
C
D001921:Brain / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006344:Heart Septal Defects, Atrial / Q000175:diagnosis*; D006801:Humans; D008875:Middle Aged; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis*; D014430:Twins, Monozygotic