pfo Studies

from Thaler DE and Cramer SC Paradoxical embolism in stroke in  Caplan LR, Biller J. Uncommon Causes of Stroke

"The choice of vein used to introduce echocardiographic contrast influences the sensitivity for PFO detection. Blood entering the right atrium via the inferior vena cava is directed towards the interatrial septum where PFOs are located whereas blood from the superior vena cava tends to be directed towards the tricuspid valve. Studies have been consistent in finding a 2.5-fold increase in diagnostic sensitivity when the contrast medium is injected via the femoral rather than the antecubital vein (Gin et al., 1993; Hamann et al., 1998).

Caplan, Louis R.; Biller, José. Uncommon Causes of Stroke (pp. 565-567). Cambridge University Press. Kindle Edition.

full citations for above:

Gin, K., Huckell, V., and Pollick, C. 1993. Femoral vein delivery of contrast medium enhances transthoracic echocardiographic detection of patent foramen ovale. J Am Coll Cardiol, 22, 1994– 2000.

Hamann, G., Schatzer-Klotz, D., Frohlig, G., et al. 1998. Femoral injection of echo contrast medium may increase the sensitivity of testing for a patent foramen ovale. Neurology, 50, 1423– 8.

ALL MY TAKE

I ASSUME ONE HUNDRED PERCENT OF OUR STUDIES BOTH TCD AND TEE BUBBLE ARE DONE THROUGH ARM VEIN BUT RHEOLOGY SHOWS FEMORAL VEIN IS 2.5 X AS GOOD.  PERHAPS WE COULD CONSIDER DOING THESE STUDIES FEMORRALLY SECOND LINE IN CHALLENGING PATIENTS SUCH AS WE HAVE HAD LATELY?  LOOK FORWARD TO EVERYONE'S THOUGHTS

DJ