Restenosis after coronary angioplasty for rapidly progressive coronary stenosis

We hypothesized that percutaneous transluminal coronary angioplasty performed on coronary stenoses that have demonstrated rapid angiographic progression would be associated with a high risk of restenosis.

High rates of restenosis have been documented after percutaneous transluminal coronary angioplasty of unstable lesions and of lesions that recur rapidly after a successful initial angioplasty. This suggests that the "activity' of the plaque at the time of angioplasty may be an important factor determining the risk of restenosis.

In our institution we recommend angiographic follow-up for all patients with successful percutaneous transluminal coronary angioplasty. In this way we identified 86 consecutive patients who, at the time of angiographic follow-up had not developed restenosis at the dilated site, but required a further percutaneous transluminal coronary angioplasty at a different site. (which was successful). Based on quantitative angiographic measurements, 45 of these lesions (rapidly progressive lesions) had significantly increased in severity in the interval between the two angiograms (7.7 +/- 3.3 months) while 41 (stable lesions) had not. Rapid progression was defined as a > 0.4 mm decrease in minimal lumen diameter between initial angiography and percutaneous transluminal coronary angioplasty. All 86 patients had further angiographic follow-up 6 months later.

Baseline clinical and angiographic variables were similar in both groups except that a higher proportion of patients in the rapid progression group had unstable angina (20% vs 5%; P < 0.05). Late loss during follow-up did not differ statistically between groups (0.31 mm) and minimal lumen diameter at follow-up was also similar (stable lesion group = 1.40 +/- 0.48 mm; rapidly progressive lesion group = 1.30 +/- 0.59 mm). The loss index (late loss divided by acute gain) was also similar in both groups (0.45 +/- 0.52 in the stable lesion group, 0.37 +/- 0.76 in the rapidly progressive lesion group). A strong correlation between acute gain and late loss was observed in the stable lesion group (r = 0.61; P < 0.0001); by contrast, there was no relationship between these two variables in the rapidly progressive lesion group (r = 0.20; P = 0.19).

Percutaneous transluminal coronary angioplasty in patients with unstable angina or with early recurrence after a first percutaneous transluminal coronary angioplasty is associated with an increased risk of restenosis. By contrast, this study shows that angiographic instability, as evidenced by rapid stenosis progression, has no deleterious effect on the occurrence of restenosis. Percutaneous transluminal coronary angioplasty thus appears as a reasonable therapeutic option for coronary stenoses that have demonstrated rapid angiographic progression in the months prior to the procedure.