In-stent neointimal proliferation correlates with the amount of residual plaque burden outside the stent: an intravascular ultrasound study.
BACKGROUND
The aim of this study was to evaluate the relationship between residual plaque burden after coronary stent implantation and the development of late in-stent neointimal proliferation.


RESULTS
Between January 1996 and May 1997, 50 patients underwent intravascular ultrasound (IVUS) interrogation at 6+/-1.2 months after coronary stent implantation in native coronary arteries. IVUS images were acquired with a motorized pullback, and cross-sectional measurements were performed within the stents at 1-mm intervals. The following measurements were obtained: (1) lumen area (LA), (2) stent area (SA), (3) area delimited by the external elastic membrane (EEMA), (4) percent neointimal area calculated as (SA-LA/SA)x100, and (5) percent residual plaque area calculated as (EEMA-SA)/EEMAx100. Volume measurements within the stented segments were calculated by applying Simpson's rule. In the pooled data analysis of 876 cross sections, linear regression showed a significant positive correlation between percent residual plaque area and percent neointimal area (r=0.50, y= 45.03+0.29x, P<0.01). There was significant incremental increase in mean percent neointimal area for stepwise increase in percent residual plaque area. Mean percent neointimal area was 16.3+/-10.3% for lesions with a percent residual plaque area of <50% and 27.7+/-11% for lesions with a percent residual plaque area of >/=50% (P<0.001). The volumetric analysis showed that the percent residual plaque volume was significantly greater in restenotic lesions compared with nonrestenotic lesions (58.7+/-4.3% versus 51.4+/-5.7%, respectively; P<0.01).


CONCLUSIONS
Late in-stent neointimal proliferation has a direct correlation with the amount of residual plaque burden after coronary stent implantation, supporting the hypothesis that plaque removal before stent implantation may reduce restenosis.
Catheterization Laboratory, Hospital, Rome, Italy.
F
F
Prati
C
C
Di Mario
I
I
Moussa
B
B
Reimers
M T
MT
Mallus
A
A
Parma
E
E
Lioy
A
A
Colombo
D000368:Aged; D002455:Cell Division; D003327:Coronary Disease / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000473:pathology*; D012008:Recurrence; D015607:Stents; D014463:Ultrasonography