The degree of right-to-left shunt in a patient with a patent foramen ovale can be graded by monitoring the flow of contrast microbubbles during transesophageal echocardiography.
Method:
(1) Insert a transesophageal Doppler echocardiography transducer.
(2) Release of contrast microbubbles in the right atrium.
(3) The number of microbubbles are counted.
Webster et al
Torti et al
Grade
no bubbles
none
0
1 to 5 bubbles (small)
few single bubbles
1
6 to 20 bubbles (medium)
between a few and a cloud
2
>= 21 bubbles (large)
cloud
3
The higher the grade the greater the shunt and the greater the risk of complications.
To read more or access our algorithms and calculators, please log in or register.