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Antonio Colombo

Publications and source records attributed to Antonio Colombo.

At least 91 records · Page 5Linked to original sources
PubMed2005

Sirolimus-eluting stent implantation in diabetic patients with multivessel coronary artery disease.

BACKGROUND: Restenosis rate is lower after sirolimus-eluting stent (SES) implantation than after bare metal stent (BS) implantation. We evaluated the impact of SES implantation on immediate and 12-month outcome in diabetic patients with multivessel coronary artery disease (MVD). METHODS: From April 2002 to September 2003, 100 consecutive diabetic patients with MVD without previous myocardial revascularization underwent successful elective percutaneous coronary intervention (PCI) with SES on native coronary arteries at our institutions. A group (n = 122) of consecutive diabetic patients with MVD treated with BS implantation (BS group) for de novo lesions was selected from our database and matched with the SES group. Major adverse cardiac events (MACEs) during hospital stay and at follow-up included nonfatal myocardial infarction, death, bypass surgery, and re-PCI. RESULTS: At 12 +/- 4 months, MACEs occurred in 25% of patients in the SES group and in 44% of those in the BS group (P = .003, OR .72, 95% CI 0.57-0.91). Need for repeat intervention (re-PCI or bypass surgery) occurred in 17% of patients in the SES group and in 41% of those in the BS group (P < .001, OR .67, 95% CI 0.52-0.86). No significant difference in the rate of death and myocardial infarction was observed. In the SES group, the independent predictors of MACEs at follow-up were premature clopidogrel discontinuation (hazard ratio 20.62, 95% CI 1.60-264.97, P = .020) and chronic renal insufficiency (hazard ratio 4.73, 95% CI 1.99-11.25, P = .0004). CONCLUSIONS: As compared with BS implantation, SES implantation favorably influences outcome in diabetic patients with MVD, mainly by reducing the need for new revascularization.

Coronary Artery Disease↗
PubMed2005

Treatment of unprotected left main coronary artery disease with drug-eluting stents: is it time for a randomized trial?

The treatment of unprotected left main coronary artery disease by percutaneous intervention represents a considerable challenge for interventional cardiologists. The American College of Cardiology/American Heart Association guidelines currently recommend surgical revascularization for this disorder and percutaneous interventions have thus far been performed only in exceptional cases, albeit with positive results in some patients. Technical limitations, however, including stent restenosis, limit the application of this technique at present. The availability of drug-eluting stents, which are associated with a reduction in angiographic restenosis, might change this situation. Preliminary results show that the implantation of drug-eluting stents for unprotected left main coronary artery lesions is a feasible and safe approach. Randomized clinical trials comparing the use of drug-eluting stents with coronary artery bypass surgery for unprotected left main coronary artery disease are the next step, but can such trials be contemplated at this stage? In this review we present an overview of the findings to date and discuss the direction that research should now take.

Angioplasty, Balloon, Coronary↗
PubMed2005

Nephrotoxicity of low-osmolality versus iso-osmolality contrast agents: impact of N-acetylcysteine.

BACKGROUND: Recent data support that iodixanol, an iso-osmolality contrast agent, is less nephrotoxic than low-osmolality contrast agents when hydration is the only prophylactic strategy used. We evaluated the nephrotoxicity of iso- and low-osmolality contrast agents with prophylactic administration of N-acetylcysteine (NAC) along with hydration. METHODS: Two hundred and twenty-five patients with chronic renal insufficiency (serum creatinine >1.5 mg/dL or an estimated glomerular filtration rate <60 mL/min/1.73 m(2)), referred to our institution for coronary and/or peripheral procedures, were assigned to receive low-osmolality (iobitridol group; N = 115) or iso-osmolality (iodixanol group; N = 110) contrast dye. In all cases prophylactic administration of 0.45% saline intravenously and NAC (1200 mg orally twice daily) was used. RESULTS: Baseline creatinine levels were similar in the 2 groups [iobitridol group = 1.70 (IQR: 1.54-1.98) mg/dL; iodixanol group = 1.73 (IQR: 1.56-2.00) mg/dL, P = 0.33]. The risk score for contrast nephrotoxicity was 5.0 +/- 1.6 in the iobitridol group versus 5.0 +/- 1.8 in the iodixanol group (P = 0.44). Increase of at least 0.5 mg/dL of the creatinine concentration 48 hours after the procedure occurred in 4/115 patients (3.5%) in the iobitridol group and 3/110 patients (2.7%) in the iodixanol group (P = 1.00; OR 0.78; 95% CI 0.17-3.56). Amount of contrast media administration was similar in the 2 groups (iobitridol group = 167 +/- 90 mL; iodixanol group = 164 +/- 82 mL; P = 0.61). CONCLUSION: Nephrotoxicity of iso-osmolality and low-osmolality contrast agents was similar when a prophylactic strategy of hydration plus NAC was utilized.

Acetylcysteine↗
PubMed2005

Evaluation of the Coroflex Theca-Stent for reduction of restenosis (ECORI).

BACKGROUND: Various stent coatings have been shown to significantly reduce restenosis rates in comparison to non-coated devices. Therefore, the short- and mid-term performance of the new polyphosphazene-coated Coroflex Theca-Stent was investigated. METHODS: 103 patients [63.9 +/- 11 yrs, 5/103 (4.9%) lesion type A, 52/103 (50.5%) type B1, and 46 of 103 (44.6%) type B2] were enrolled for elective single stent deployment into de-novo coronary lesions (stenoses: greater than or equal to 70%, < 100%; reference diameter greater than or equal to 2.75 mm, less than or equal to 4 mm; lesion length: < 16 mm). RESULTS: Deployment and procedural success were 100%, in 57/103 (55.3%) patients without pre-dilatation. 3/103 (2.9%) patients were lost to follow-up. During the 7.1 +/- 2.3 months clinical follow-up, 3 of 100 (3.0%) patients underwent premature target lesion revascularizations, 4 /100 (4%) had non-target lesion-related deaths, and 1 of 100 (1%) suffered myocardial infarction. Among the 77 of 100 (77.0%) patients who underwent angiographic follow-up, the initial stenosis declined from 87.3 +/- 5.7% to 14.2 +/- 8.3% after stenting, and increased to 32.8 +/- 22.7% after 6.4 +/- 1.3 months. The late loss and late loss index were 0.6 +/- 0.7 mm and 0.2 +/- 0.4, respectively; the recurrence rate was 12 of 77 (15.6%), with reintervention required in 11 of 77 (14.3%) of these patients. CONCLUSION: The Coroflex Theca-Stent provides excellent procedural results and a low restenosis rate. Further development of this polymer as the final coating and as the basis for drug-eluting stents seems justified.

Angioplasty, Balloon, Coronary↗
PubMed2005

[Drug-eluting stents: from the results of clinical studies to economic simulation models in the Italian reality].

Several studies with drug-eluting stents (DES) have demonstrated dramatic reductions in restenosis rates compared with bare metal stents (BMS). Although the clinical benefits of DES are increasingly evident, important concerns about their costs have been raised. Most data regarding the impact of restenosis on long-term costs after percutaneous coronary intervention (PCI) are derived from clinical trials. These studies demonstrate that there is no single cost or economic burden of restenosis; these values vary substantially according to the specific patient population under investigation and to the healthcare system reality where they are applied. In the present study we propose an economic interactive decision model which was applied to the Italian healthcare system, considering the different reimbursement rates of the Italian regions for DES and for both PCI and coronary artery bypass surgical interventions (CABG). The aim of this model was to simulate the impact of DES introduction after potential complete reimbursement by the national healthcare system, hypothesizing the usage of 1.4 stent per patient in case of single vessel disease and 2.4 stents in case of multivessel disease, and utilizing the TAXUS IV rate of revascularization for reintervention costs calculation and the ARTS-I study for CABG costs. For a low risk patients' population, the mean cost of a procedure with DES was 6% greater than utilizing BMS (xi 8125 for DES vs xi 7651 for BMS). However, this percentage was reduced in case of diabetic patients (+4%), long lesions (+2%) and was favourable for small vessels (-3%). In addition, in case of multivessel disease with conversion from CABG to DES, the 12 months cost per patients was reduced of around 30% (xi 10 170 for PCI vs xi 14 584 for CABG). This model suggests that national healthcare system may save 2.1% of the total costs (xi 18.60 millions) if 60% of revascularization procedures converts to total DES utilization and 15% from CABG to PCI with DES.

Clinical Trials as Topic↗
PubMed2005

[Severe aortic stenosis successfully treated with percutaneous aortic valve implantation].

Patients with severe calcific aortic stenosis are occasionally not amenable to surgery because of advanced age or severe co-morbidities. Percutaneous aortic valve dilation is used but has only limited time relief. While preclinical evidence on percutaneous aortic valve replacement seems promising, only very limited clinical data are available worldwide. We hereby present the first case of percutaneous aortic valve replacement successfully performed in Italy in a 74-year-old high-risk female. This case emphasizes the technical challenges inherent to this procedure and its promising role in selected very high-risk patients with severe aortic stenosis, notwithstanding the early and long-term risk of adverse events.

Aged↗
PubMed2005

Bifurcation lesions.

The introduction of drug-eluting stents has significantly improved the immediate and long-term results following treatment of bifurcation coronary lesions. Despite these improvements, few questions are still without a clear answer. Among them the most important one is the need to use two stents vs provisional side branch stenting in true bifurcations. At present time the approach most frequently applied is to stent the main branch stenting to the side branch only for suboptimal results. In situations when the operator needs two stents as intention to treat we suggest the usage of the "Crush" or "V" technique. These two approaches have been utilized with good immediate and long-term results with sirolimus-eluting stents and with polymer-based paclitaxel-eluting stents. The usage of the "Crush" technique followed by final dilation of the side branch and with kissing balloon inflation has decreased. We recently evaluated results with this technique in 70 patients treated with sirolimus-eluting stents. The 6-month angiographic follow-up was available in 83% of the lesions and restenosis rate was 33% (7% main and side branches and 26% only side branch). No difference was observed in the restenosis rate on the main branch between lesions treated with final kissing balloon inflation and lesions without final kissing inflation (4% in the final kissing group vs 8% in the no final kissing group, p = 1.00). The restenosis rate on the side branch was lower in the final kissing group (17%) in comparison to the no final kissing group (42%) (p = 0.046). Similar results are achieved with polymer-based paclitaxel-eluting stents. The introduction of drug-eluting stents with selective usage of stenting the main and side branches applying the "Crush" or "V" techniques has significantly improved the results compared to bare metal stents in bifurcation lesions.

Blood Vessel Prosthesis Implantation↗
PubMed2004

Nonuniform strut distribution correlates with more neointimal hyperplasia after sirolimus-eluting stent implantation.

BACKGROUND: Little is known about causes of intimal hyperplasia (IH) after sirolimus-eluting stent (SES) implantation. METHODS AND RESULTS: Intravascular ultrasound was performed in 24 lesions with intra-SES restenosis and a comparison group of 25 nonrestenotic SESs. To assess stent strut distribution, the maximum interstrut angle was measured with a protractor centered on the stent, and the visible struts were counted and normalized for the number of stent cells. In SES restenosis patients, minimum lumen site was compared with image slices 2.5, 5.0, 7.5, and 10.0 mm proximal and distal to this site. The minimum lumen site had a smaller IVUS lumen area at follow-up (2.7+/-0.9 versus 6.2+/-1.9 mm2; P<0.01), larger maximum interstrut angle (135+/-39 degrees versus 72+/-23 degrees; P<0.01), larger IH area (3.4+/-1.5 versus 0.6+/-1.1 mm2; P<0.01) and thickness (0.7+/-0.3 versus 0.1+/-0.2 mm; P<0.01) at maximum interstrut angle, and fewer stent struts (4.9+/-1.0 versus 6.0+/-0.5; P<0.01) even when normalized for the number of stent cells (0.78+/-0.15 versus 0.97+/-0.07; P<0.01). Compared with nonrestenotic SES, the restenosis lesions also had a smaller minimal lumen area, larger IH area, thicker IH at maximum interstrut angle, fewer stent struts, and larger maximum interstrut angle. Multivariate analysis identified the number of visualized stent struts normalized for the number of stent cells and maximum interstrut angle as the only independent IVUS predictor of IH cross-sectional area (P<0.01 and P<0.01), minimum lumen area (P<0.01 and P<0.01), and IH thickness (P<0.01 and P<0.01). CONCLUSIONS: The number and distribution of stent struts affect the amount of neointima after SES implantation.

Aged↗
PubMed2004

Comparison of clinical and angiographic outcome of sirolimus-eluting stent implantation versus cutting balloon angioplasty for coronary in-stent restenosis.

Sixty in-stent restenotic lesions were treated with sirolimus-eluting stent implantation and retrospectively compared with a group of matched lesions treated with cutting balloon angioplasty. The results indicate a good safety profile of the procedure and a 57% reduction in the incidence of recurrent restenosis in comparison with cutting balloon angioplasty.

Angioplasty, Balloon, Coronary↗
PubMed2004

High-dose 7-hexanoyltaxol-eluting stent with polymer sleeves for coronary revascularization: one-year results from the SCORE randomized trial.

OBJECTIVES: The Study to COmpare REstenosis Rate between QueST and QuaDDS-QP2 (SCORE) trial was a multicenter, randomized, open-label trial comparing the safety and performance of 13- and 17-mm QuaDDS stents (n = 126) (Quanam Medical Corp., Santa Clara, California/Boston Scientific Corp., Natick, Massachusetts) versus uncoated control stents (n = 140) in focal, de novo coronary lesions. BACKGROUND: The pioneering drug-delivery QuaDDS stent used four to six acrylate polymer sleeves, each loaded with 800 microg of the paclitaxel derivative 7-hexanoyltaxol. METHODS: Clinical end points were assessed at 1, 6, and 12 months post procedure. Quantitative coronary angiography and intravascular ultrasound were performed post procedure and at six-month follow-up. RESULTS: In the QuaDDS group, early stent thrombosis and myocardial infarction (MI) rates were significantly higher, leading to premature cessation of enrollment. For the QuaDDS group, the stent thrombosis rate increased from 3.2% to 10.3% between 1 and 12 months, associated with increased non-Q-wave MI and death rates. The angiographic restenosis rate at six months was reduced from 32.7% (control) to 7.4% (p < 0.0001). However, the primary end point was not met with six-month target vessel revascularization (TVR) rate as well as the composite major adverse cardiac event rates (cardiac death, MI, and TVR) comparable between groups. CONCLUSIONS: Despite angiographic indications of potential anti-restenotic benefit, increased rates of stent thrombosis, MI, and cardiac death associated with the QuaDDS stent show an unacceptable safety profile.

Aged↗