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Carlo Di Mario

Publications and source records attributed to Carlo Di Mario.

At least 55 records · Page 3Linked to original sources

A randomized comparison of direct stenting versus stenting with predilatation in native coronary artery disease: results from the multicentric Crosscut study.

Stenting without predilatation has become possible due to the availability of a new generation of flexible, low-profile, securely crimped, balloon-expandable stents. This study compared the feasibility, efficacy and cost-effectiveness of direct stenting (DS) to the standard predilatation technique (PS) using the premounted Crossflex LC stent (Cordis Corporation, Miami Lakes, Florida). The study is a randomized prospective multicenter evaluation including 271 patients (140 patients in the DS group and 131 patients in the PS group) with 1 or 2 de novo or restenotic lesions located in native coronary arteries. Procedural success was 98.9% and 98.7% in the DS and PS groups, respectively (p = NS); crossover to PS was required in 22/166 lesions (13.2%) enrolled in the DS group because of inability to cross the target lesion without predilatation. Nonsignificant reductions in procedural time (-10.5%), fluoroscopy time (-4.7%) and amount of contrast (-3.8%) were observed in the DS group in comparison to the PS group. The number of balloons used (-76.6%) and the global cost of the procedure (-18.8%) were significantly lower in the DS group (p < 0.01 for both comparisons). After 6 months, no differences were observed in the restenosis rate between the two groups (22.0% for DS group versus 18.1% for PS group; p = NS) and in the incidence of major adverse clinical events (5.0% for DS group versus 3.0% for PS group; p = NS). Direct stenting is safe and feasible for the treatment of lesions in native coronary arteries and obtains a significant reduction in procedural cost, mainly due to the lower number of balloons used. Clinical and angiographic results at 6 months are comparable to those obtained after a conventional predilatation-stenting strategy.

Catheterization↗

Insulin-treated diabetes mellitus and predictors of mid-term clinical outcome after percutaneous coronary interventions with stent implantation.

BACKGROUND: Patients with type II, insulin-dependent diabetes mellitus have a high risk of death and repeat revascularization following successful percutaneous coronary interventions. The predictors of outcome in such patients after coronary stenting have not been clarified. METHODS: We studied 133 consecutive patients with type II, insulin-dependent diabetes mellitus who underwent coronary stenting from November 1992 to May 2001. The clinical outcome and predictors of major adverse cardiac events (MACE; that is death, myocardial infarction, target vessel revascularization) at follow-up were assessed. RESULTS: Out of 133 patients, 102 (76%) had multivessel (> or = 2 vessels) disease. Eight patients (6.0%) had in-hospital MACE. Clinical follow-up data at 19.5 months (range 6.1-100 months) were available for 121 (91%) patients. The MACE rate was 40.5%; 22 patients (18%) died, 17 (14%) of a cardiac death; 7 (5.8%) patients had a myocardial infarction, and target vessel revascularization was performed in 35 (28.9%) patients. At univariate analysis, hypertension (odds ratio-OR 5.5; confidence interval-CI 2.5-12.3; p < 0.001), hypercholesterolemia (OR 3.7; CI 1.7-8.2; p = 0.001), a prior percutaneous coronary intervention (OR 6.6; CI 2.9-15.4; p < 0.001), a prior myocardial infarction (OR 3.1; CI 1.5-6.7; p = 0.003) and the stent length (> or = 15 mm) (OR 2.7; CI 1.5-4.3; p = 0.008) were related to MACE. At multivariate analysis, hypertension (OR 4.1; CI 1.7-9.9; p = 0.002), a prior percutaneous coronary intervention (OR 4.8; CI 1.9-12; p = 0.001) and the stent length (OR 3.0; CI 1.3-7.4; p = 0.01) remained as independent predictors of MACE. CONCLUSIONS: Patients with insulin-dependent diabetes mellitus continue to face a high mortality and incidence of adverse events after stenting. The occurrence of events was related to a history including hypertension, percutaneous coronary interventions and to the stent length.

Aged↗

Effects of selective alpha1- and alpha2-adrenergic blockade on coronary flow reserve after coronary stenting.

BACKGROUND: Coronary flow reserve (CFR) is not normalized shortly after coronary stenting. We hypothesized that alpha-adrenergic coronary vasoconstriction acts to limit CFR. METHODS AND RESULTS: We assessed flow velocity by Doppler wires and cross-sectional area by angiography in 46 patients undergoing coronary culprit lesion stenting (81+/-4% stenosis). Hyperemia was induced by adenosine (24 micro g IC or 140 micro g/kg per minute IV) before and after stenting. Finally, either the alpha(1)-antagonist urapidil (10 mg IC) or the alpha(2)-antagonist yohimbine (3 mg IC) was randomly combined with adenosine. In 8 subjects with angiographically normal coronary arteries, CFR was increased from 3.21+/-0.30 to 3.74+/-0.43 by yohimbine and to 4.58+/-0.65 by urapidil, respectively (P=0.0001). Patients were divided according to the cutoff of CFR > or =3.0 (n=18) or <2.5 (n=28). Revascularization per se did not change CFR. However, 15 minutes after stenting, CFR decreased to 2.05+/-0.55 from CFR 3.64+/-0.58, whereas in patients with CFR 2.39+/-0.51, it remained unchanged. Yohimbine improved CFR to 3.26+/-0.42 and to 3.41+/-0.58 in patients with >3.0 and <2.05+/-0.55 baseline CFR, respectively. Urapidil improved CFR to 3.52+/-0.30 and 3.98+/-1.07, respectively. CONCLUSIONS: Urapidil and yohimbine attenuated the CFR impairment occurring after revascularization by increasing both the epicardial vasodilator effect of adenosine and the blood flow velocity, thus suggesting that the adrenergic system plays an important role in limiting the capacity of the coronary circulation to dilate.

Adenosine↗

Mechanism of late in-stent restenosis after implantation of a paclitaxel derivate-eluting polymer stent system in humans.

BACKGROUND: We recently reported delayed angiographic restenosis in 15 patients who received 7-hexanoyltaxol (QP2)-eluting polymer stents (QuaDS) for the treatment of in-stent restenosis. This study presents the histological findings of atherectomy specimens from a subset of these patients receiving implants. METHODS AND RESULTS: Between October and December 2001, 5 patients treated with QuaDS-QP2 stents underwent directional coronary atherectomy at 11.2+/-1.0 months for recurrent in-stent restenosis. Restenotic lesion composition was assessed with special stains, immunohistochemistry with quantitative image analysis, and, in one specimen, transmission electron microscopy. Atherectomy specimens contained fibrin interspersed in a smooth muscle cell-rich neointima with proteoglycan matrix. In 2 of 5 specimens, large aggregates of macrophages and T-lymphocytes were noted. These areas of active inflammation demonstrated a relatively high proliferation index by Ki-67 antibody staining, whereas the proliferation index in smooth muscle cell-rich restenotic areas was low. CONCLUSION: Restenotic lesions from QuaDS-QP2-eluting stents at 12 months show persistent fibrin deposition with varying degrees of inflammation. These pathological changes, representing delayed healing, are usually observed up to only 3 months in human coronary arteries with stainless steel balloon-expandable stents. The nonreabsorbable polymer alone may have induced chronic inflammation.

Aged↗

7-hexanoyltaxol-eluting stent for prevention of neointimal growth: an intravascular ultrasound analysis from the Study to COmpare REstenosis rate between QueST and QuaDS-QP2 (SCORE).

BACKGROUND: Inhibition of neointimal tissue growth has been demonstrated in preliminary human feasibility studies with a stent-based polymer sleeve delivering 7-hexanoyltaxol. The Study to COmpare REstenosis rate between QueST and QuaDS-QP2 (SCORE) trial is a human, randomized, multicenter trial comparing 7-hexanoyltaxol (QP2)-eluting stents (qDES) with bare metal stents (BMS) in the treatment of de novo coronary lesions. The purpose of this substudy was to evaluate the acute expansion property and long-term neointimal responses of qDES compared with BMS as assessed by intravascular ultrasound (IVUS). METHODS AND RESULTS: A total of 122 (qDES 66, BMS 56) patients were enrolled into the IVUS substudy. All IVUS images (immediately after the procedure and at 6-month follow-up) were analyzed at an independent core laboratory in a blind manner. At baseline, qDES achieved stent expansion similar to BMS. At follow-up, qDES showed reduced neointimal growth by 70% at the tightest cross section and by 68% over the stented segment (P<0.0001 for both), resulting in a significantly larger lumen in qDES than in BMS. Unlike intracoronary brachytherapy, there was no evidence of negative edge effects, unhealed dissections, or late stent-vessel wall malapposition over the stented and adjacent references segments in either group. CONCLUSIONS: Detailed IVUS analysis revealed that qDES had comparable acute mechanical and superior long-term biological effects to BMS. Although the long-term benefits and limitations of this technology require further investigation, the reduction in neointimal thickenings demonstrated that local delivery of 7-hexanoyltaxol through polymer sleeves augments conventional mechanical treatment of atherosclerotic disease.

Blood Vessel Prosthesis Implantation↗

In-stent restenosis in small coronary arteries: impact of strut thickness.

UNLABELLED: OBJECTIVES; We sought to evaluate whether strut thickness may impact the restenosis rate after stent implantation in small coronary arteries. BACKGROUND: Small vessel size (<3.0 mm) is an independent risk factor for the occurrence of in-stent restenosis. It has been reported that vessel damage induced during stent deployment is an important factor in restenosis. METHODS: From our database, we selected all patients who had successful stenting in small native vessels, with angiographic follow-up available, between March 1996 and April 2001. The strut was defined as thin when <0.10 mm and thick when > or = 0.10 mm. According to these criteria, we identified two subgroups: a thin group and a thick group. RESULTS: A total of 821 (57%) of the 1,447 patients had angiographic follow-up available and were included in the analysis. The thin group included 400 patients with 505 lesions. The thick group included 421 patients with 436 lesions. The restenosis rate was 28.5% in the thin group and 36.6% in the thick group (p = 0.009; odds ratio [OR] 1.44, 95% confidence interval [CI] 1.09 to 1.90). The study group was classified into three subgroups according to the reference vessel diameter: < or = 2.50 mm, 2.51 to 2.75 mm and 2.76 to 2.99 mm. Strut thickness influenced the restenosis rate only in the subgroup with a reference vessel diameter between 2.76 and 2.99 mm, with rates of 23.5% in the thin group and 37% in the thick group (p = 0.006). By logistic regression analysis, predictors of restenosis were stent length (OR 1.03, 95% CI 1.01 to 1.04; p = 0.001), strut thickness (OR 1.68, 95% CI 1.23 to 2.29; p = 0.001) and diabetes mellitus (OR 2.10, 95% CI 1.21 to 3.68; p = 0.007). CONCLUSIONS: This study supports that strut thickness is an independent predictor of restenosis in coronary arteries with a reference diameter of 2.75 to 2.99 mm.

Aged↗

Results and long-term predictors of adverse clinical events after elective percutaneous interventions on unprotected left main coronary artery.

BACKGROUND: The safety and efficacy of percutaneous coronary intervention of de novo lesions in unprotected left main coronary arteries remains an unresolved issue. METHODS AND RESULTS: We analyzed 67 consecutive patients treated with the following devices: 39 with stents, 12 with rotational atherectomy plus stents, 13 with directional coronary atherectomy plus stents (a total of 64 patients were treated with stents), and 3 patients with directional coronary atherectomy only. The reference vessel size was 3.78+/-0.73 mm and lesion length was 6.6+/-3.0 mm. In-hospital complications were 2 coronary artery bypass grafts (CABGs) (3.0%), 2 Q-wave myocardial infarctions (MIs) (3.0%), and 3 non-Q-wave MIs (4.5%); there were no deaths. The estimated cardiac survival at 3 years was 91%. The cardiac mortality rate was higher in patients with Parsonnet score >15 versus < or =15 (21.4% versus 4.2%, P=0.02) at 3 years. The independent covariate of cardiac death was preserved left ventricular ejection fraction; for combined cardiac events (cardiac death, MI, repeat revascularization) it was large reference vessel size. Follow-up angiography at 5+/-2 months in 85% of eligible patients revealed 31.4% restenosis. Extending the follow-up to 31+/-23 months (19 patients with follow-up beyond 3 years) the cumulative event rates were 11 deaths (16.4%), 8 of them cardiac (11.9%), 2 (3.0%) MI, and 16 (23.9%) repeat revascularizations (CABG in 5 patients). CONCLUSIONS: Elective percutaneous coronary intervention of de novo lesions in left main coronary arteries is feasible, with low procedural risk. The long-term follow-up revealed a high rate of angiographic restenosis and repeat revascularization, with a relatively high incidence of cardiac death. Reference vessel size and left ventricular function are the most important predictors of favorable follow-up.

Adult↗

Outcome of nonobstructive residual dissections detected by intravascular ultrasound following percutaneous coronary intervention.

The purpose of this study was to assess the outcome of nonobstructive (or non-flow-limiting) residual dissection (RD) after percutaneous coronary intervention. Results of 124 consecutive native coronary lesions with angiographic nonobstructive RD in 97 patients (RD group) were compared with outcomes of 124 lesions without RD in 100 patients (non-RD group), whose characteristics were matched with those of the RD group. RD occurred after stent implantation (81 of 124 lesions, 65%) or balloon angioplasty (43 of 124 lesions, 35%). Angiographic types of RD were type A in 8 lesions (6%), B in 101 (82%), and C in 15 (12%). Stents were implanted in 65% of the lesions in each group. Clinical success (94% in RD group vs 95% in non-RD group, p = 0.77) and the in-hospital major adverse cardiac event rates were found to be similar in the 2 groups (6% vs 3%, respectively; p = 0.33). The late angiographic and clinical outcomes were also comparable. By intravascular ultrasound (IVUS) evaluation of the dissections in the RD group, area stenosis correlated with the incidence of in-hospital major adverse cardiac events (p = 0.023), whereas the final minimal lumen area correlated inversely with the occurrence of restenosis (p = 0.011). An area stenosis > or =58% was the best predictor for the incidence of in-hospital major adverse cardiac events (sensitivity 0.68, specificity 0.68). Most nonobstructive RDs are "favorable" and do not need stent implantation. IVUS evaluation identifies "unfavorable" nonobstructive (or non-flow-limiting) dissections that might be prone to acute occlusion. Nonobstructive dissections can be left untreated when final IVUS reveals an area stenosis of < 60% at the site of a dissection.

Aortic Dissection↗

Recombinant apolipoprotein A-I(Milano) infusion into rabbit carotid artery rapidly removes lipid from fatty streaks.

Apolipoprotein A-I(Milano) (AIM), a natural variant of human apolipoprotein A-I, confers to carriers a significant protection against vascular disease. In previous studies, administration of recombinant AIM-phospholipid (AIM-PL) complexes to hypercholesterolemic rabbits markedly inhibited neointimal formation after arterial injury; moreover, repeated injections of AIM-PL in apoE-deficient mice significantly reduced atherosclerosis progression. The objective of the present study was to determine if a single localized infusion of AIM-PL complexes administered directly to atheromatous lesions could promote plaque regression. Lipid-rich, atheromatous plaques were generated at both common carotid arteries of 25 rabbits by applying a perivascular electric injury, followed by 1.5% cholesterol diet for 90 days. Rabbits were infused with either saline, phospholipid vesicles, or 3 different AIM-PL doses (250, 500, or 1000 mg of protein) delivered through an intravascular ultrasound (IVUS) catheter positioned at the origin of the right carotid. The lesions at the left carotid artery were therefore exposed to the agents systemically. Infusion of AIM-PL at the 2 highest doses caused reduction of right carotid artery plaque area by the end a 90-minute infusion as assessed by IVUS analysis. Plaque area regression was confirmed by histology in carotid arteries receiving direct (500 and 1000 mg doses) and systemic (500 mg dose) delivery, 72 hours after the start of the treatment. Plaque lipid content was associated with significant and similar decreases in Oil Red O staining in both arteries. These results suggest AIM-PL complexes enhanced lipid removal from arteries is the mechanism responsible for the observed plaque changes.

Animals↗

First clinical experience with a paclitaxel derivate-eluting polymer stent system implantation for in-stent restenosis: immediate and long-term clinical and angiographic outcome.

BACKGROUND: It has been shown that antiproliferative drugs such as paclitaxel lower the amount of intimal hyperplasia after stent implantation. We report the first clinical experience of 7-hexanoyltaxol (QP2)-eluting polymer stent system (QuaDS) implantation for in-stent restenosis. METHODS AND RESULTS: Fifteen consecutive patients with elective indication to percutaneous coronary intervention for in-stent restenosis were treated with the QuaDS-QP2 stent implantation. The QuaDS-QP2 stent was successfully implanted in all but 2 target lesions. In one lesion, the restenotic segment could not be completely covered by the stent, and in another lesion, a bare metal stent was implanted distally to the QuaDS-QP2 stent. One patient suffered from postprocedural non-Q-wave myocardial infarction (NQWMI). No other adverse events were observed during hospital stay. Six- and 12-month angiographic and clinical follow-up was scheduled for all patients. At 6 months, 3 patients had target lesion revascularization (20%). Two patients had restenosis (13.3%); one experienced restenosis in a gap between 2 drug-eluting stents, and the other had stent occlusion leading to NQWMI. Minimal intimal hyperplasia was observed in all the segments covered by drug-eluting stents (late loss=0.47+/-1.01 mm with a loss index=0.17+/-0.39). At 12 months, 1 patient suffered from NQWMI, and 8 of 13 patients (61.5%) had angiographic restenosis (late loss=1.36+/-0.94 mm with a loss index=0.62+/-0.44). CONCLUSION: This first experience with QuaDS-QP2 stent implantation for in-stent restenosis revealed minimal intimal hyperplasia at the 6-month follow-up. However, the antiproliferative effect was not maintained at the 12-month follow-up, resulting in delayed occurrence of angiographic restenosis.

Bridged-Ring Compounds↗

Polytetrafluoroethylene-covered stent and coronary artery aneurysms.

Angiographically detected coronary aneurysms (i.e., coronary segment greater then 1.5 times the normal artery) have an incidence of 0.3%-4.9% among patients undergoing coronary angiography and have been reported after an intervention procedure with a frequency of 2%-10%. The indication for treatment and the best modality still need to be defined. Some authors reported the successful treatment of coronary aneurysms with the polytetrafluoroethylene (PTFE)-covered stent implantation, supporting the role of this strategy. In our institution, from September 1997 to December 1999 eight PTFE-covered stents were implanted to treat seven coronary aneurysms in seven patients. All aneurysms were successfully treated by the PTFE-covered stent. In one case, there was the necessity of an additional PTFE stent to cover the aneurysm completely. In no case did the loss of stent occur. No in-hospital MACE occurred. At 35 +/- 8 (21-44) months, six patients were symptom-free. Angiographic follow-up was performed in all patients at 10 +/- 6 months. Restenosis occurred in one patient (14%) who had repeat percutaneous coronary interventions. This preliminary experience suggests that PTFE-covered stent may be useful in the treatment of coronary artery aneurysms.

Adult↗

Directional atherectomy of a calcified lesion using a new atherectomy device.

We report on a case of directional atherectomy performed on a calcified coronary lesion using a novel device with a hardened titanium cutter. The successful removal of calcified plaque was documented by intravascular ultrasound assessment and confirmed by histopathological analysis of the obtained plaque specimen.

Atherectomy, Coronary↗

Effective plaque removal with a new 8 French-compatible atherectomy catheter.

The purpose of this study was to evaluate the safety and efficacy of the new 8 Fr guide catheter-compatible Flexicut directional atherectomy device and to compare it with the conventional Atherocath GTO catheter. The 6 Fr Flexicut catheter has a larger cutting window and a titanium nitride-coated cutter to effect more tissue removal as well as treat mildly calcified lesions. A group of 143 lesions in 117 consecutive patients treated with the Flexicut catheter in four centers were compared with a control group of 277 lesions in 212 consecutive patients treated with the GTO device. Postatherectomy luminal diameters were larger (2.92 +/- 0.79 vs. 2.52 +/- 0.64 mm; P < 0.0001), with more luminal gain (relative gain: 0.58 +/- 0.24 vs. 0.48 +/- 0.25; P = 0.0007) using fewer directional coronary atherectomy (DCA) cuts (12 +/- 7 vs. 16 +/- 9; P = 0.0001) in the Flexicut group. A residual diameter stenosis < 20% immediately after DCA was obtained in 77% of the lesions in the Flexicut group vs. 45% in the GTO group (P < 0.0001). Histology in the former group revealed large calcium speckles in the retrieved specimens. In the Flexicut group, there was a lower incidence of access site complications and damage to the coronary ostium (2.5% vs. 7.5%; P = 0.08). The new Flexicut catheter is more effective than the conventional GTO catheter with a trend for reduced guiding catheter-related complications.

Atherectomy, Coronary↗

The lunar stent characteristics and clinical results.

One of the frequent long-term complications after stent implantation is restenosis due to the building up of a neointima within the artery, as well as endovascular hyperplasia (tissue growth). The interesting feature of the Lunar stent from Inflow Dynamics is that it is coated with a layer of iridium oxide. The iridium oxide coating is believed to reduce restenosis by decreasing the inflammatory response to the stent via its antioxidant action. The MOONLIGHT (Multicenter Objective ObservatioNal Lunar Iridiumoxide intimal GrowtH Trial) study was carried out to evaluate the immediate outcome and long-term angiographic success after implantation of Lunar stents. Between March 2001 and November 2001, 87 patients with 99 lesions were enrolled in this study and were treated with 12 and 16 mm long iridium-oxide coated Lunar stents. Delivery of the Lunar stent was successful in most lesions and the optimal radiopacity facilitated optimal stent positioning with optimal immediate clinical and angiographic results is an unselected patient and lesion population. Preliminary clinical and angiographic follow-up show a low rate of cardiac events at 6 months (16.1% MACE) and a moderate hyperplastic response.

Adult↗

Sirolimus-eluting stents: a review of experimental and clinical findings.

Sirolimus (rapamycin), a macrolide antibiotic with known potent immunosuppressive properties, acts in the first phase (G1) of the cell cycle, blocking its further progression to the phase of DNA synthesis (S). In experimental models, rapamycin is effective in inhibiting smooth muscle cell proliferation and migration after vessel wall injury with balloon angioplasty. These results lead to the clinical application of sirolimus-eluting stents in 45 patients in Sao Paulo and Rotterdam (FIM Registry) and 238 patients in a randomized, European multicenter trial (RAVEL). These trials showed, by angiography and intravascular ultrasound, almost complete abolition of in-stent late hyperplasia up to one year after the procedure. In this review, we describe the experimental and clinical results of sirolimus-eluting stents including our experience of 26 stents implanted in 17 patients. In elective de novo lesions has shown remarkably clear lumens at follow-up angiography and intravascular ultrasound within the stented segments were observed with no lesion progression at the stent margins or thrombosis after a 2 month regimen of aspirin, and ticlopodine or clopidogrel. New large-scale ongoing clinical trials will investigate the efficacy of sirolimus-eluting stents in lesions that are traditionally associated with high restenosis rates after stent implantation, such as long lesions, bifurcations and instent restenosis.

Angina Pectoris↗