We describe our initial experience with the "Big Skinny" angioplasty catheter, currently only available as an investigational device and in sizes of 4.5, 5, and 6 mm. Six patients with severe angina pectoris were successfully dilated with this angioplasty catheter and have remained asymptomatic up until a mean follow-up period of 6 months. However, because of the large profile of the catheter, sufficient back-up with an adequate guiding catheter should be obtained and predilation with a smaller angioplasty catheter should be performed. The use of this catheter may be a more simple alternative for the treatment of oversized vessel stenosis than the "hugging balloon" technique or directional atherectomy. Otherwise, it may be considered as an adjunct technique in order to optimize the angiographic result after stenting or directional arthrectomy in this particular indication.