| Popis: |
Elective native coronary artery stenting has shown its efficacy in lowering restenosis rates (RR) usually occurring after balloon angioplasty (PTCA). However ability of conventional PTCA to consistently provide low RR, through the achievement of large acute stent-like angiographic results, has not been investigated. This study was conducted to: (1) assess ability of optimal initial dilatation (OID), defined by residual lumen narrowingor = 20%, significantly reduce current high RR following traditional PTCA; (2) evaluate the efficacy of OID obtainable by conventional PTCA in influencing adverse effects of single variables predisposing to restenosis.Of consecutive 601 patients who underwent PTCA, 569 (94.6%), 483 men and 86 women, aged 38-76 years, had a successful procedure on 645/678 lesions (95.1%). After a plaque fracture was obtained by the first inflation, step-increases in pressure of 1 atm and 60 second-inflation-times were applied, until a large lumen (the nearest to normal) and smooth contours were seen, or any wall damage detected by using step-by-step angiographic tests. Acute optimal results (group A) were 450 (69.7%) and sub-optimal results (group B) were 203 (30.3%). After a mean time of 9 +/- 1.8 months, 543 patients (95.4%) had angiographic restudy on 611 (94.7%) successfully treated lesions.Restenosis (50% stenosis at restudy) occurred in 27.1% of patients and in 24.5% of lesions. RR was 18.8% in group A and 37.8% in group B (p0.0001). Significant lower RR were observed in group A in comparison with group B, for single variables examined, except for length10 mm. By multivariate analysis of all treated lesions, sub-optimal initial dilatation, unstable angina, lesion length10 mm and eccentricity emerged as major determinants of restenosis. Following OID only length10 mm was highly predictive of this event and, in the absence of this adverse variable, RR was only 13.6%.Counterbalancing adverse effects of many variables predisposing to restenosis, OID obtained by traditional PTCA seem to significantly reduce the risk of recurrence, particularly in lesions no longer than 10 mm. |
