Change in diameter of coronary artery segments adjacent to stenosis after percutaneous transluminal coronary angioplasty: Failure of percent diameter stenosis measurement to reflect morphologic changes induced by balloon dilation

Abstract

To determine the changes in stenotic and nonstenotic segments of a dilated coronary artery, detailed quantitative angiographic measurements were performed in 342 patients (398 lesions) immediately after angioplasty and at a predetermined follow-up time of 30, 60, 90 or 120 days after the dilation. Measurements of the stenotic segments were expressed as minimal luminal diameter, and the adjacent nonstenotic segments were expressed as interpolated reference diameter (both in millimeters). A follow-up rate of 86% was achieved. In the patients followed up at 30 and 60 days, there was no significant change in either the mean minimal luminal diameter or the mean reference diameter. However, at 90 and 120 days, there was significant deterioration in both the mean minimal luminal diameter (-0.37 and -0.42 mm, respectively) and the mean reference diameter (-0.17 and -0.26 mm, respectively), all of the changes being highly significant (p less than 0.00001). The reference diameter is involved in the dilation process and may be subject to the same restenosis process that takes place in initially stenotic segments. Percent diameter stenosis measurements, which are conventionally used to express the change in the severity of a stenosis after angioplasty, will tend to underestimate the change when there is a simultaneous reduction in the reference diameter.

Comparison of Late Luminal Loss Response Pattern After Sirolimus-Eluting Stent Implantation or Conventional Stenting

“…It has been reported that some degree of late loss occurs even for nonrestenotic lesions after percutaneous interventions with bare stents. 1,7 In a previous study with conventional stenting, Schomig et al 7 have shown that lesions in the lower range of lumen renarrowing still presented a late lumen loss of Ϸ0.5 mm, a number similar to that observed in our control group. SES implantation, however, has been shown in our series to virtually abolish neointimal formation in nonrestenotic lesions.…”

“…However, it remains a matter of debate whether restenosis simply represents an extreme form of the "normal" vessel healing response after mechanical dilatation or if it is related to specific mechanisms that ultimately lead to vessel renarrowing. [1][2][3][4][5][6][7] Although several cutoff criteria have been proposed to dichotomize patients with restenosis from those without restenosis, it has been widely recognized that, to some extent, late luminal reduction is a ubiquitous phenomenon, occurring even in those categorized as not having binary restenosis. 1,7 Recently, drug-eluting stents with the antiproliferative agent sirolimus have proved to reduce neointimal growth markedly in clinical trials.…”

“…[1][2][3][4][5][6][7] Although several cutoff criteria have been proposed to dichotomize patients with restenosis from those without restenosis, it has been widely recognized that, to some extent, late luminal reduction is a ubiquitous phenomenon, occurring even in those categorized as not having binary restenosis. 1,7 Recently, drug-eluting stents with the antiproliferative agent sirolimus have proved to reduce neointimal growth markedly in clinical trials. In the First-in-Man (FIM) study 8 and the Randomized Study With the Sirolimus-Eluting Bx Velocity Balloon-Expandable Stent in the Treatment of Patients With De Novo Native Coronary Artery Lesions (RAVEL), 9,10 no cases of binary angiographic restenosis were seen after sirolimus-eluting stent (SES) implantation.…”

Reproducibility of Measurements of Coronary Narrowings by Videodensitometry and by Digital Calipers

“…There may be no view which shows the long axis of the artery, or there may be poor or nonuniform filling and failure to center the artery. Yet the necessity for an objective, repeatable method of analyz ing cinefilms of coronary arteriograms is of increasing importance in order to assess the effects of various mechanical interventions, such as balloon angioplasty, and the effects of newly available medications, which have the potential to modify progression or to result in regression of coronary artery lesions [ 12-l 4], To date, attempts to measure changes in coronary artery' stenoses following PTCA, us ing automated edge detection techniques, have encountered many pitfalls [15], as changes in the contour of the normal segment may occur following PTCA. In addition, bor der recognition techniques require consider able operator interaction in the setting of PTCA in order to distinguish between true flow channels and blind pouches created as a result of the angioplasty [ 16].…”

Reestenose pós-angioplastia. Fisiopatogenia

“…Este espessamento intimal é uma característica da resposta da parede vascular à injúria e ocorre independentemente da técnica de angioplastia utilizada 6,7 . Histologicamente, a hiperplasia da íntima difere significativamente da placa aterosclerótica, quanto à arquitetura celular e ao conteúdo lipídico.…”