Intravascular ultrasound assessment of the novel AngioSculpt scoring balloon catheter for the treatment of complex coronary lesions.

BACKGROUND: Despite the advances in interventional cardiology, stent expansion remains an important predictor of success, impacting restenosis and thrombosis rates after either bare-metal (BMS) or drug-eluting stent implantation. Especially for the treatment of complex lesions (e.g., calcified lesions, in-stent restenosis, etc.), adequate lesion preparation might help improve procedural results as well as clinical outcomes. We sought to investigate the safety, feasibility and mechanism of action of a new scoring-balloon catheter, the AngioSculpt, comprised of a semicompliant balloon and a nitinol spiral cage designed to address complex lesions. METHODS: A total of 60 consecutive patients at two centers were prospectively enrolled in this first-in-man coronary study and divided into two groups according to the type of lesion treated: Group I: patients with de novo coronary lesions (n = 47) as a pretreatment strategy before BMS implantation, and Group II: patients with BMS restenosis (n = 17) as a standalone therapy. A subgroup of patients in each cohort was assigned to intravascular (IVUS) analysis. Patients in Group II were submitted to routine 6-month follow-up angiography. In Group I, angiographic restudy was contingent upon the presence of ischemia. Lesions longer than 20 mm in very tortuous vessels, in arterial or vein grafts, in the setting of acute myocardial infarction or with visible thrombus were excluded from this study. RESULTS: Success was achieved in all cases. The mean age of the study populations was 62 +/- 11.6 years (Group I) and 53 +/- 9.4 years (Group II), with 26% and 18% diabetics, respectively. In Group I, 73% of lesions were diffuse and fibrocalcified, while in Group II, 72% were classified as diffuse. No serious complications were observed in either group. Balloon slippage (or the "watermelon seed" phenomenon) was not observed. Significant acute gain was achieved in both groups (0.7 mm in Group I and 1.64 mm in Group II). A minimum final area (in-stent) 6.5 mm2 was achieved in 85% of the cases in Group I and in 82% of the cases in Group II. CONCLUSIONS: In this preliminary in vivo study, the use AngioSculpt(R) proved to be feasible and safe for the treatment of complex coronary lesions. Six-month results suggest the use of this novel device as an attractive option for the percutaneous approach of restenotic coronary lesions and should be assessed in a larger, more complex cohort of patients.

A three-dimensional intravascular ultrasound comparison between the new zotarolimus-eluting stent (ZoMaxx) and the non-drug-eluting TriMaxx stent.

BACKGROUND: Despite the effectiveness of sirolimus- and paclitaxel-eluting stents in reducing intimal hyperplasia (IH) and the need for repeat revascularization, concerns about their long-term safety have motivated the search for new drug-eluting stents (DES). Recently developed, the ZoMaxx stent combines a sirolimus-analogous agent (zotarolimus), featuring a phosphorycoline polymer and stainless steel and tantalum platform. We sought to assess the efficacy of this new DES in reducing IH. METHODS: A total of 40 patients were treated with the ZoMaxx stent and compared to 50 patients treated with its non-drug-eluting equivalent, the TriMaxx stent. Only single de novo lesions in native coronary vessels greater than or equal to 3.0 mm were enrolled. Serial quantitative coronary angiography and intravascular ultrasound (IVUS) images were obtained at baseline and 6- month follow up. All patients were clinically followed for 1 year. This analysis aimed to compare the percent of IH between the 2 stents. Secondarily, we assessed in-segment late loss, binary restenosis and major adverse cardiac events. RESULTS: Baseline patient and lesion characteristics were comparable between the 2 groups. At follow up, zotarolimus efficiently suppressed neointimal hyperplasia formation with a marked reduction in the percentage of stent obstruction by IVUS (4.6 +/- 3.6% vs. 31.2 +/- 16%; p < 0.0001). Almost 90% of the segments stented with ZoMaxx did not exhibit more than 10% of obstruction. After 1 year, 12 patients treated with the TriMaxx and 2 patients treated with the ZoMaxx presented in-segment binary restenosis (p = 0.03). CONCLUSIONS: In this initial experience, ZoMaxx proved to be clinically safe and superior to its non-drug-coated equivalent in reducing in-stent IH formation and restenosis.

Long-term follow-up of incomplete stent apposition in patients who received sirolimus-eluting stent for de novo coronary lesions: an intravascular ultrasound analysis.

BACKGROUND: Incomplete stent apposition (ISA) has been previously documented after sirolimus-eluting stent (SES) implantation. The aim of this study was to investigate the long-term intravascular ultrasound (IVUS) findings of ISA in patients who received SES. METHODS AND RESULTS: A total of 13 patients who received SES and showed ISA at follow-up IVUS (follow-up I) were investigated. IVUS was performed on all of these patients 12 months later (follow-up II). Quantitative ISA area measurement was also performed at follow-up I and II. No vascular remodeling was observed in the vessel segment with ISA; external elastic membrane area was 19.4+/-6.6 versus 19.5+/-6.4 mm2 at follow-up I and II, respectively. There was also no significant change in external elastic membrane area between vessel segment with ISA and without ISA (+1.5% versus -3.0%, respectively; P=0.27) at late follow-up. The ISA area, either including (2.5+/-1.7 versus 3.8+/-6.3 mm2; P=NS) or excluding (2.5+/-1.8 versus 2.4+/-1.7 mm2; P=NS) a single patient with aneurysm formation, was not significantly different between follow-up I and II. One patient manifested a coronary aneurysm in the stented segment at late follow-up that was probably present at the initial follow-up but masked by thrombus. It was successfully treated with a covered stent. All patients were asymptomatic, and no patient experienced late thrombotic occlusion. CONCLUSIONS: Vessel dimensions and area of ISA did not change over time, except for 1 coronary aneurysm that became apparent. ISA after implantation of a SES was not associated with adverse events at late follow-up.

Intravascular ultrasound findings in the multicenter, randomized, double-blind RAVEL (RAndomized study with the sirolimus-eluting VElocity balloon-expandable stent in the treatment of patients with de novo native coronary artery Lesions) trial.

BACKGROUND: The goal of this intravascular ultrasound investigation was to provide a more detailed morphological analysis of the local biological effects of the implantation of a sirolimus-eluting stent compared with an uncoated stent. METHODS AND RESULTS: In the RAVEL trial, 238 patients with single de novo lesions were randomized to receive either an 18-mm sirolimus-eluting stent (Bx VELOCITY stent, Cordis) or an uncoated stent (Bx VELOCITY stent). In a subset of 95 patients (sirolimus-eluting stent=48, uncoated stent=47), motorized intravascular ultrasound pullback (0.5 mm/s) was performed at a 6-month follow-up. Stent volumes, total vessel volumes, and plaque-behind-stent volumes were comparable. However, the difference in neointimal hyperplasia (2+/-5 versus 37+/-28 mm3) and percent of volume obstruction (1+/-3% versus 29+/-20%) at 6 months between the 2 groups was highly significant (P<0.001), emphasizing the nearly complete abolition of the proliferative process inside the drug-eluting stent. Analysis of the proximal and distal edge volumes showed no significant difference between the 2 groups in external elastic membrane or lumen and plaque volume at the proximal and distal edges. There was also no evidence of intrastent thrombosis or persisting dissection at the stent edges. Although there was a higher incidence of incomplete stent apposition in the sirolimus group compared with the uncoated stent group (P<0.05), it was not associated with any adverse clinical events at 1 year. CONCLUSIONS: Sirolimus-eluting stents are effective in preventing neointimal hyperplasia without creating edge effect and without affecting the plaque burden behind the struts.