Coronary artery fistulas are extremely rare and coil occlusion by intervent
ion techniques seems to be the therapy of choice. We describe the case of a
3-month-old infant with a coronary artery fistula. During occlusion of the
fistula a coronary guide wire got entrapped in a small coronary branch, bu
t could be successfully retrieved with a microsnare without damage to the h
eart. The microsnare technique prevented rupture of the guide wire.