Regional differences in elastic recoil after percutaneous transluminal coronary angioplasty: a quantitative angiographic study.

The immediate result of percutaneous transluminal coronary angioplasty is influenced by both plastic and elastic changes of the vessel wall. To evaluate the amount of elastic recoil after coronary balloon angioplasty, the minimal luminal cross-sectional area of the largest balloon used at highest inflation pressure was compared with the minimal luminal vessel cross-sectional area directly after final balloon deflation in 607 lesions (526 patients). Elastic recoil was defined as the difference between balloon cross-sectional area and minimal luminal cross-sectional area of the dilated coronary segment immediately after balloon withdrawal. A videodensitometric analysis technique was used to avoid geometric assumptions on stenosis morphology directly after angioplasty. Mean balloon cross-sectional area was 5.3 +/- 1.6 mm2 and minimal luminal cross-sectional area after angioplasty was 2.8 +/- 1.4 mm2. Reference areas before and after angioplasty did not differ (6.0 +/- 2.6 and 6.2 +/- 2.6 mm2, respectively). Univariate analysis revealed that asymmetric lesions, lesions located in less angulated parts of the artery and lesions with a low plaque content showed more elastic recoil. Lesions located in distal parts of the coronary tree were also associated with more elastic recoil probably related to relative balloon oversizing in these distal lesions.