When a stenotic lesion is suggested, the patient should be evaluatedwith angiography to determine if an anatomically significant lesion isactually present. Lesions that represent 50% stenosis or greater should betreated. Angioplasty should be regarded as a standard option for themanagement of venous stenosis associated with dialysis access. Thereshould be no more than a 30% residual stenosis following angioplasty;however, the current literature recommends that the goal should be noresidual stenosis following treatment.Currently, the most frequent form of tPA in use for dysfunctionaldialysis catheters is alteplase (Cathflo). This is a recombinant form of thenaturally occurring tPA.