Dear Ben,
About one to two percent of cardiac catheterizations are complicated by vascular problems such as hematomas involving the artery used to gain access into the circulation. It is extremely unusual for this problem to occur a year after the catheterization, and the two events might not be related. Hematomas are large blood clots that form when there is bleeding around the puncture site. In some cases, something known as a fistula can occur, with blood flowing from the artery into the adjacent vein. Also, aneurysms or pseudoaneurysms describe conditions where there is an outpouching of the artery, usually at the site of puncture.
Aneurysms can be corrected by a small procedure performed by a vascular surgeon. During the procedure, the surgeon can inspect the artery for any other problems that might cause aneurysms, including infection and degenerative changes. The fluid that you mention is likely saline, a salt/water mixture that approximates the qualities of the plasma in our blood.
Best of luck. Information in the Heart Forum is for general purposes. Specific diagnoses and therapies can only be provided by your physician.