Intermittent claudication: its natural course.

Of more than 600 patients seen for intermittent claudication by this group and not primarily considered for surgery, 104 had angiographic studies and are the basis for this report. The follow-up period varied from 6 months to 8 years, with a mean of 2.5 years. Classification by severity of claudication revealed 33 with less than one block, 36 with two blocks, and 35 with two or more blocks, foot, calf, or thigh claudication. Eighty-two remained stable or improved and 22 worsened. Of the 22 who worsened, 16 had only worsening of claudication (six of them requiring arterial reconstruction) and six progressed to gangrene and required amputations. Of the 82, 66 either had marked improvement of claudication or remained sufficiently stable not to require any operative intervention. Sixteen required arterial reconstruction for persistent, intolerable, or incapacitating claudication. Five of the six amputees were from the less than one half block claudication group. Angiographic studies were significant only in relation to the below-knee runoff in that three of 25 with less than one vessel runoff, two of 23 with one to two vessel runoff, and one of 56 with two to three vessel runoff came to amputation, regardless of the pattern of more proximal arterial occlusions. The study suggests that intermittent claudication is relatively benign, with only 5.8 percent coming to amputation in a 2.5 year mean follow-up. Prognosis is determined by the severity of below-knee arterial involvement and apparent inability to compensate for ischemia via the collateral circulation since only 12.5 percent of those with the most pronounced involvement came to amputation.