Showing papers by "Rodolfo Staico published in 2005"

Comparison between sirolimus-eluting stents and intracoronary catheter-based beta radiation for the treatment of in-stent restenosis.

Abstract: We report the outcomes of patients who had in-stent restenosis (IRS) that was treated with intravascular brachytherapy (IVBT) or sirolimus-eluting stent (SES) implantation. The benefit of IVBT for treating ISR is well documented. SES implantation decreases first-time ISR and, in preliminary reports, has been used to treat ISR. Fifty consecutive patients who had ISR were treated; the first 25 patients underwent SES implantation and the next 25 patients were treated with IVBT using a beta-Cath System (a 40-mm strontium-90/yttrium-90 source). Quantitative angiographic and intravascular ultrasound follow-up were performed at 5.2 +/- 1.1 and 12.1 +/- 1.2 months; clinical follow-up was performed at 15 months. SES deployment and IVBT were successful in all patients. At 12-month follow-up, 8 patients who underwent IVBT had angiographic recurrence (4 in the stent and 4 at the stent edge); only 1 patient who underwent SES implantation developed recurrent ISR. At 12 months, in-stent late luminal loss was similar between the SES and IVBT groups (0.35 +/- 0.45 vs 0.34 +/- 0.46 mm, p = 0.9); however, in-stent net luminal gain was higher in the SES group than in the IVBT group (1.32 +/- 0.13 vs 0.57 +/- 0.19 mm, p <0.0001), and in-lesion late luminal loss was higher in the IVBT group (0.48 +/- 0.32 vs 0.16 +/- 0.42 mm, p = 0.004). At 12 months, intravascular ultrasound stent volume obstruction was higher after IVBT versus than after SES implantation (38.7% vs 6.7%, p <0.0001). At 15-month clinical follow-up, 64% and 96% (p <0.01) of patients who underwent IVBT and SES implantation, respectively, were free of major adverse cardiac events. In conclusion SES implantation for the treatment of ISR was effective and superior to catheter-based IVBT in preventing recurrent neointimal proliferation and angiographic restenosis at 1-year follow-up.

Angiographic and intravascular ultrasound findings of the late catch-up phenomenon after intracoronary beta-radiation for the treatment of in-stent restenosis.

Abstract: We report one-year angiographic and intravascular ultrasound (IVUS) outcomes of in-stent restenosis (ISR) patients treated with intravascular brachytherapy (IVBT). The benefit of IVBT for treating ISR is well documented. However, few data exist on significant angiographic and intravascular ultrasonic in-stent lumen deterioration beyond the habitual 6-month analysis after the index radiation procedure or so-called late catch-up process in the treatment of ISR. Twenty-five consecutive patients with ISR were treated with IVBT using the Beta-Cath System (a 40 mm 90 Sr per 90 gamma source). Quantitative angiographic and IVUS analysis was performed in all of them at 6 and 12 months. IVBT was successful in all patients. Four patients (16%) developed recurrent angiographic binary restenosis at 6-month follow-up, all located within the adjacent reference segments, with 2 being associated with geographical miss. An additional 4 patients (16%) presented with recurrent ISR at 12-month follow-up, all within the stented segment. Significant in-stent lumen loss (0.16 +/- 0.42 mm to 0.34 +/- 0.46 mm; p = 0.008) and in-stent intimal hyperplasia growth (+11.2 +/- 0.48 mm3; p = 0.03) was observed between 6 and 12 months. Intracoronary beta-radiation for the treatment of ISR was associated with significant luminal deterioration (late catch-up) within the stents between 6 and 12 months due to an important late progression of in-stent intimal hyperplasia.

Pilot study with an intensified oral sirolimus regimen for the prevention of in-stent restenosis in de novo lesions: A serial intravascular ultrasound study

Abstract: This pilot study evaluated the safety and efficacy of an intensified oral sirolimus regimen (15-mg loading dose 24 hr before PCI, followed by a daily dose of 5 mg for 4 weeks) in 15 patients subjected to elective bare metal coronary stent implantation for de novo lesions. Mean patient age was 59 ± 9; 73% were male, and 13% were diabetic patients. The reference diameter was 3.04 ± 0.38 mm, and the lesion length was 14 ± 2 mm. Angiographic and volumetric intravascular ultrasound (IVUS) analyses were performed in all patients at 6.0 ± 0.2 months. Two patients (13%) met the definition of in-segment binary restenosis; in-stent and in-segment angiographic late loss was 0.61 ± 0.31 mm and 0.67 ± 0.45 mm, respectively, and the percent neointimal volume was 28.5 ± 15.8%. At adjacent reference segments, there was neither significant plaque increase nor constrictive vascular remodeling. At 24-month follow-up no deaths, myocardial infarctions, or target lesion revascularizations were detected. Mean sirolimus blood level was 13 ± 7 ng/ml. No correlations were found between drug levels and late loss (r = 0.15, P = 0.59) or IVUS percent neointimal volume (r = 0.23, P = 0.47). Side effects were frequent (80%), leading to dose reductions in four and drug discontinuation in one patient. The results of this pilot study suggest that an intensified 5-mg oral sirolimus regimen resulted in no relevant improvements in the angiographic and IVUS parameters of restenosis after stent implantation in de novo lesions when compared with historic controls. Considering the efficacy/safety balance, our results do not encourage further trials evaluating the current protocol for the prevention of in-stent restenosis. © 2005 Wiley-Liss, Inc.

IMPACT Trial: angiographic and intravascular ultrasound observations of the first human experience with mycophenolic acid-eluting polymer stent system.

Abstract: The purpose of the study was to examine the safety and efficacy of two different formulations of mycophenolic acid (MPA)-eluting Duraflex stents on coronary de novo lesions. Recent data indicate that local delivery of MPA in the porcine overstretch coronary model significantly reduces neointimal hyperplasia (NIH). Patients were divided into three consecutive groups. The first (n=50) and second (n=55) groups received moderate- and slow-release MPA-eluting Duraflex stent, respectively. The last group (n=50) received the bare metal Duraflex stent. Clinical, angiographic, and intravascular ultrasound analysis were performed at 6-month follow-up. All stents were successfully deployed and patients were discharged home without clinical events. Compared to controls, 6-month in-lesion and in-stent minimum luminal diameter as well as late lumen loss were not significantly different in the moderate- and slow-release treatment groups. At follow-up, percentage obstruction and NIH volume were also similar between the three groups. At 30 days and 6 and 12 months, there were no differences noted between the three groups with respect to major adverse cardiac events as well as the individual rates of mortality, myocardial infarction, or repeat revascularization. There were no cases of subacute or late thrombosis. In this feasibility trial, the MPA-eluting Duraflex stents in either slow- or moderate-release formulations were well tolerated, but showed no benefit for treatment of coronary lesions when compared to controls. Further testing with different drug dosing or delivery rate might improve these results.

A Novel Mechanism Explaining Early Lumen Loss Following Balloon Angioplasty for the Treatment of In-Stent Restenosis

Abstract: We performed serial intravascular ultrasound analysis in patients who underwent balloon dilatation for in-stent restenosis. Early lumen loss was detected by intravascular ultrasound and was associated with minimal changes at the edges and at the external elastic membrane. These results on intravascular ultrasound suggest compression and decompression as the main mechanisms for early lumen loss after dilatation of in-stent restenotic lesions.