Endomyocardial biopsy causing coronary artery-right ventricular fistula after cardiac transplantation.

We present 3 cases of coronary artery-right ventricular fistulae diagnosed on yearly check-ups on 160 cardiac transplant patients between September 1982 and January 1995. The fistula was communicating with the ventricular branch of the right coronary artery, the septal branch of the left anterior descending artery and the distal right coronary artery in the three cases being reported. Histological examination of the endomyocardial biopsy specimen showed the presence of small calibre arteries which were not seen in other cases. Although endomyocardial biopsy carries a risk of less than 0.5 percent, the possibility of causing coronary artery-ventricular fistula should be added to the list of the complications of this procedure. The shunt caused by these fistulae is small and has no hemodynamic significance and usually does not warrant any treatment.