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C Di Mario

Publications and source records attributed to C Di Mario.

At least 37 records · Page 2Linked to original sources
PubMed2001

Predictors of diffuse and aggressive intra-stent restenosis.

OBJECTIVES: This study was performed to investigate the causes of diffuse and aggressive intra-stent restenosis. BACKGROUND: Although restenosis is usually considered to be a dichotomous variable, there is clinical relevance to the severity of restenosis. It is not known which variables are predictive of diffuse or aggressive intra-stent restenosis. METHODS: A consecutive series of 456 coronary lesions with in-stent restenosis was evaluated for the type of restenosis using quantitative coronary angiography. Restenosis was defined as > or = 50% diameter stenosis at follow-up angiography, diffuse restenosis as a follow-up lesion length > or = 10 mm and aggressive restenosis as either an increase in lesion length from the original lesion or a restenotic narrowing tighter than the original. Clinical, anatomic and procedural characteristics were evaluated for lesions associated with these types of restenosis. RESULTS: Diffuse restenosis was associated with a smaller reference artery diameter, longer lesion length, female gender, longer stent length and the use of coil stents. Aggressive restenosis was more common in women, with the use of Wallstents and with long stent to lesion length ratios. Aggressive restenosis occurred earlier and was more closely associated with symptoms and myocardial infarctions than nonaggressive restenotic lesions. CONCLUSIONS: Markers for diffuse restenosis were also important markers for the presence of any restenosis. A long stent to lesion length ratio is an important marker for aggressive restenosis. When severe forms of in-stent restenosis occur, they tend to present earlier and with more symptoms, including myocardial infarction. More careful consideration of the type of in-stent restenosis may aid in identifying when alternative strategies may be useful.

Coronary Angiography↗
PubMed2001

Intravascular ultrasound criteria for the assessment of the functional significance of intermediate coronary artery stenoses and comparison with fractional flow reserve.

The functional significance of coronary artery stenoses of intermediate severity is important in determining strategy in patient care. Intravascular ultrasound (IVUS) is often used to evaluate coronary stenosis severity. However, at present, few data are available about the role IVUS in the assessment of functional significance of intermediate lesions. Myocardial fractional flow reserve (FFR) <0.75 is a reliable index of a functionally severe coronary stenosis. In 53 lesions we assessed (1) by pressure wire: FFR (index of functional significance), and (2) by IVUS: minimal lumen cross-sectional area (MLA, square millimeters), minimal lumen diameter (MLD, millimeters), lesion length (millimeters), and percent area stenosis at the lesion site. By regression analysis, percent area stenosis and lesion length had a significant inverse correlation with FFR (r = -0.58, p <0.001, r = -0.41, p <0.004, respectively). MLD and MLA showed a significant positive relation with FFR (r = 0.51, p <0.001, r = 0.41, p <0.004, respectively). By using a receiver operating characteristic (ROC) curve, we identified a percent area stenosis > 70% (sensitivity 100%, specificity 68%), a MLD < or = 1.8 mm (sensitivity 100%, specificity 66%), a MLA < or =4.0 mm2 (sensitivity 92%, specificity 56%), and a lesion length of >10 mm (sensitivity 41%, specificity 80%) to be the best cut-off values to fit with a FFR <0.75. The combined evaluation of both percent area stenosis and MLD made the IVUS examination more specific (sensitivity 100%, specificity 76%). In 53 intermediate coronary lesions found by angiography, IVUS area stenosis >70%, MLD < or =1.8 mm, MLA < or =4.0 mm2, and lesion length > 10 mm reliably identified functionally critical intermediate coronary stenoses.

Cardiac Catheterization↗
PubMed2001

Directional atherectomy prior to stenting in bifurcation lesions: a matched comparison study with stenting alone.

The ideal catheter-based intervention for treatment of coronary lesions at bifurcation site still has to be defined. The aim of the study was to assess the acute and long-term outcome after treatment of bifurcation lesions with directional atherectomy (DCA) and stenting in comparison with stenting alone. Thirty-one consecutive patients treated for bifurcation coronary lesions (62 lesions) with DCA and stenting in at least one branch (DCA group) were compared with a matched group of 31 patients with bifurcation coronary lesions (62 lesions) treated with stenting alone in at least one branch (non-DCA group). Procedural success was 87.1% in the DCA group compared with 100% in the non-DCA group (P = 0.03). In-hospital major adverse cardiac events (MACE) occurred only in the DCA group (12.9% vs. 0%, P = 0.03), mainly non-Q-wave myocardial infarction. After the procedure, minimum lumen diameter (MLD) and acute gain were significantly greater (P = 0.004 and P = 0.05, respectively) and % diameter stenosis was significantly lower (P = 0.05) in the main branch in the DCA group. At follow-up angiogram, MLD in the main branch was still significantly greater in the DCA group compared to the non-DCA group (2.31 vs. 1.65, respectively, P = 0.04), with no significant difference in late loss and loss index between the two groups. Restenosis rate was 28.8% in the DCA group vs. 43.5% in the non-DCA group (P = 0.13). The incidence of follow-up MACE was 29% in the DCA group compared with 48.4% in the non-DCA group, mainly due to target lesion revascularization. In conclusion, treatment of bifurcation coronary lesions with DCA and stenting was associated with greater acute gain after the procedure and greater MLD at follow-up in the main branch compared with stenting alone. Procedural myocardial infarction was more frequent in the DCA group. Restenosis rates and follow-up MACE were lower following DCA and stenting, without reaching any statistical significance.

Adult↗
PubMed2001

Late acute thrombosis after coronary brachytherapy: when is the risk over?

Late total occlusion (LTO) after simultaneous coronary stenting and brachytherapy has been described in recent randomized trials. We report a case of LTO presenting with an acute clinical event 15 months after the index procedure, suggesting that the risk is not confined to the first 6-month to 1-year period.

Blood Vessel Prosthesis Implantation↗
PubMed2001

Cutting balloon angioplasty for treatment of calcified coronary lesions.

The aim of the study was to evaluate the feasibility, safety, and efficacy of cutting balloon angioplasty in treatment of angiographically moderate and severe calcified coronary lesions. Thirty-seven calcified coronary lesions (29 patients) detected by angiography were dilated with cutting balloon. Predilatation with plain balloon was performed in 27 (73.0%) lesions and stent was implanted in 23 (62.2%) lesions following cutting balloon. Acute gain following cutting balloon in predilated lesions was compared to the acute gain following plain balloon predilatation. For predilated lesions, acute gain after cutting balloon was significantly greater compared with plain balloon predilatation (1.51 +/- 0.49 vs. 0.77 +/- 0.42; P = 0.01). This result was achieved with larger size and lower pressure of cutting balloon compared with plain balloon (3.28 +/- 0.46 vs. 2.94 +/- 0.55, P = 0.01; 10.38 +/- 1.64 vs. 13.19 +/- 3.63, P = 0.001, respectively). The final gain following cutting balloon dilatation was significantly higher than the expected gain obtained by using a plain balloon of the same size (1.51 +/- 0.49 vs. 0.93 +/- 0.48; P < 0.0001), which was inflated at significantly higher pressure compared with cutting balloon. When we compared acute gain following cutting balloon in lesions with and without predilatation, we found no significant difference (P = 0.31). Angiographic success was achieved in 36 (97.3%) lesions and procedural success in 33 (89.1%) lesions. In-hospital major adverse cardiac event (MACE) occurred in three (10.3%) patients. Follow-up MACE was reported from three (10.3%) patients. In conclusion, cutting balloon angioplasty is feasible and safe in treatment of angiographically moderate and severe calcified lesions. Dilating efficiency of cutting balloon seems to be greater compared with a plain balloon of the same size, which was inflated at significantly higher pressure compared with cutting balloon. These results can be achieved with low in-hospital MACE and are associated with a good long-term outcome.

Aged↗
PubMed2001

Development of a lipid-rich, soft plaque in rabbits, monitored by histology and intravascular ultrasound.

Lipid rich, soft plaques in the clinic are a common forerunner to occlusive thrombus formation, even with modest arterial stenosis. Animal models of atherosclerosis, obtained by various methods, do not generally allow direct in vivo evaluation of the lesion and, furthermore, cannot be examined more than once. The aim of the study was the generation of a rabbit model of atherosclerosis, with morphological characteristics similar to human lipid-rich, soft atheromatous plaques, and the evaluation of the reliability of intravascular ultrasound (IVUS) technology in the study of the development of atherosclerotic lesions in this model. Briefly, New Zealand white rabbits undergo perivascular electrical injury at both common carotid arteries, together with a 1.5% cholesterol diet for up to 90 days. The lesioned arterial segments show progressive changes, from diffuse cellular mortality, to macrophage infiltration in the media, up to the final migration of macrophages to the neointima, resulting in bulky, eccentric, macrophage and lipid-rich lesions. At IVUS, the produced lesions clearly resemble those described as 'soft plaques' in the clinical setting, with minimal calcification and reduced echo-reflectivity versus the adventitial layer. Quantitative and morphometric analysis of plaques shows a significant correlation between histological and IVUS measurements at each time point. In conclusion, vascular injury in the common carotids of rabbits generates atherosclerotic lipid-rich, soft plaques, that can be properly assessed by the IVUS methodology. The easy accessibility of the arterial lesion allows serial IVUS investigations and the direct evaluation of a number of locally or generally delivered therapeutic agents.

Analysis of Variance↗
PubMed2001

Cutting balloon angioplasty for the treatment of in-stent restenosis: a matched comparison with rotational atherectomy, additional stent implantation and balloon angioplasty.

OBJECTIVES: The purpose of the study was to determine whether cutting balloon angioplasty (CBA) has advantages over other modalities in treatment of in-stent restenosis (ISR). BACKGROUND: Controversies exist regarding optimal treatment for ISR. Recently, CBA emerged as a tool in management of ISR. METHODS: A total of 648 lesions treated for ISR were divided into four groups according to the treatment strategy: CBA, rotational atherectomy (ROTA), additional stenting (STENT), and percutaneous transluminal coronary angioplasty (PTCA). Following the matching process, 258 lesions were entered into the analysis. RESULTS: Baseline clinical and angiographic characteristics were similar among the groups (p = NS). Acute lumen gain was significantly higher in the STENT group (2.12 +/- 0.7 mm), whereas in the CBA group the gain was similar to one achieved following ROTA and following PTCA (1.70 +/- 0.6 vs. 1.79 +/- 0.5 mm and 1.56 +/- 0.7 mm, respectively; p = NS). The lumen loss at follow-up was lower for the CBA versus ROTA and versus STENT (0.63 +/- 0.6 vs. 1.30 +/- 0.8 mm and 1.36 +/- 0.8 mm, respectively; p < 0.0001), yielding a lower recurrent restenosis rate (20% vs. 35.9% and 41.4%, respectively; p < 0.05). By multivariate analysis, CBA (odds ratio [OR] = 0.17; confidence interval [CI], 0.06 to 0.51; p = 0.001) and diffuse restenosis type at baseline (OR = 2.07; CI, 1.15 to 3.71; p = 0.02) were identified as predictors of target lesion revascularization. CONCLUSIONS: We conclude that CBA is a safe and efficient technique for treatment of ISR, with immediate results similar to atheroablation and better clinical and angiographic outcomes at follow-up. This approach might be implemented as a viable option in management of focal ISR and to prepare diffuse ISR for brachytherapy treatment.

Aged↗
PubMed2001

Characterization of total occlusions with intracoronary ultrasound: the importance of the duration of occlusion.

OBJECTIVE: To assess the impact of the occlusion duration on the characteristics of coronary occlusive plaques. BACKGROUND: The percutaneous recanalization of chronic total coronary occlusions is a technically demanding and yet often unsuccessful procedure due to unfavorable morphological changes described by histology but not well defined in vivo. METHODS: Thirty-five consecutive total occlusions of > or = 1 month duration in previously untreated native coronary arteries were studied using intracoronary ultrasound following dilatation with a 1.5 mm balloon. Plaque characteristics of lesions with an occlusive duration of > or = 3 months (old occlusions) and those of < 3 months (recent occlusions) were then compared. The ultrasound cross-section where there was maximal plaque accumulation at the site of occlusion was analyzed for its qualitative and quantitative characteristics. The lesion remodeling index was defined as the vessel area at occlusion divided by the vessel area at a proximal reference. RESULTS: The old occlusion group comprised 11 lesions whereas 16 lesions were found in the recent occlusion group; the occlusion duration was undetermined in the remaining 8 lesions, and the mean occlusion duration was found to be 4.9 +/- 4.3 months, over a range of 1 36 months. The baseline clinical and angiographic characteristics were similar in the 2 groups. The lesion remodeling index was found to be significantly lower in older occlusions than in the more recent occlusions (0.75 +/- 0.14 vs. 1. 06 +/- 0.25; p = 0.007) and the duration of the occlusion also correlated with the length of calcified segment as determined by ultrasound (p = 0.040), and with a smaller angiographic proximal reference diameter (p = 0.043). CONCLUSION: Long-standing occlusions undergo lesion shrinkage and exhibit more extensive calcification.

Adult↗
PubMed2001

Surgical and percutaneous myocardial angiogenesis induction. Part II--neoangiogenesis.

Coronary artery bypass surgery and angioplasty provide symptomatic relief in patients with ischemic heart disease, but despite advancement in technique and devices, these methods are not applicable to a subset of patients with angina refractory to medical treatment. Bypass surgery might not be feasible because of lack of suitable conduits, diffuse coronary disease or poor distal run-off, and coronary angioplasty is sometimes not applicable due to chronic total occlusion, diffuse disease or extreme tortuosity. We have previously reviewed the available experience with laser-induced direct myocardial revascularization, one of the new potential treatment modalities for this patient subset. One of the potential mechanisms of action for laser treatment is the induction of neoangiogenesis. In the second part of our article we review the available experience with the induction of myocardial angiogenesis using different growth factors or the genes encoding for them.

Coronary Disease↗
PubMed2001

Predictors of re-occlusion after successful recanalization of chronic total occlusion.

UNLABELLED: The objective of this study was to highlight the incidence and predictors of re-occlusion after successful recanalization of chronic total coronary occlusions. METHODS AND RESULTS: Following successful recanalization and stent implantation in 716 coronary lesions (665 patients) with chronic total occlusion, four hundred and five (56.6%) lesions (375 patients) underwent repeat angiography within 6 months. Restenosis (> or = 50% lumen narrowing) was observed in 151 (37.3%) lesions; forty-three (10.6%) of these lesions had complete re-occlusion and constituted the study population. In this group, final angiographic minimal lumen diameter (MLD) was 2.6 +/- 0.51 mm and final percent diameter stenosis was 18 +/- 11. Univariate analysis revealed significant correlation between re-occlusion and restenotic lesions, final balloon diameter, final percent diameter stenosis, final angiographic MLD, number of stents per lesion and total stent length. By multivariate analysis, the only independent predictor of re-occlusion was total stent length (OR = 1.46, 95% CI = 1.12-1.82; p = 0.0069). CONCLUSION: Re-occlusion occurs in about 11% of cases after stenting chronic total occlusion. The most important predictor of re-occlusion seems to be stent length.

Aged↗
PubMed2001

[New methods of coronary imaging II. Intracoronary ultrasonography in clinical practice].

Coronary angiography remains the standard technique for the assessment and therapy of coronary artery disease. Recently, intravascular ultrasound (IVUS) has emerged as a new adjunctive invasive tool which allows the acquisition of direct images of the atherosclerotic plaque in the cardiac catheterization laboratory; however it cannot be considered as an alternative to angiography. The aim of this article was to describe the indications, technique, and interpretation of IVUS imaging and its diagnostic and therapeutic applications, to review the pertaining literature and report the experience from our catheterization lab group. Ultrasound provides a unique method to study the regression or progression of atherosclerotic lesions in vivo. Lipid-laden lesions appear hypoechoic, fibromuscular lesions generate low-intensity or "soft echos" while the fibrous and calcified tissue impedes ultrasound penetration, obscuring the underlying vessel wall (acoustic shadowing). IVUS has been used to evaluate arterial remodeling: positive remodeling is the increase in arterial size to compensate for plaque accumulation and represents a compensatory mechanism to preserve lumen size; negative remodeling is vessel shrinkage and has been implicated in restenosis after balloon angioplasty. Positive remodeling seems to be significantly more frequent in myocardial infarction and unstable angina, negative remodeling occurs more often in stable coronary syndromes and is the main mechanism of restenosis after balloon angioplasty. In ostial and bifurcation lesion, the stenosis may be obscured by overlapping contrast-filled structures. Intermediate stenoses are particularly problematic in patients whose symptomatic status is difficult to assess. In these ambiguous situations, ultrasound provides a tomographic perspective, independent of the radiographic projection, which often allows precise lesion quantification. IVUS has emerged as the optimal method for the detection of diffuse post-transplant vasculopathy. Rapidly progressive intimal thickening (> 0.5 mm increase) in the first year after transplantation has major negative prognostic significance. The safety of IVUS is well documented, with studies reporting complication rates varying from 1 to 3%; the complications most frequently reported is transient spasm. Ultrasound allows us to evaluate plaque morphology, plaque eccentricity and lesion length, often helping in procedural decision-making. IVUS demonstrates plaque fracture and arterial wall dissection more often than angiography. Coronary angiograms frequently underestimate disease burden, whereas IVUS identifies residual plaque burden and minimal lumen diameter as the most powerful predictor of clinical outcome (restenosis). Several IVUS studies of directional atherectomy have addressed the issue of more aggressive plaque removal possibly resulting in decreased angiographic restenosis rate. IVUS imaging has played a pivotal role in the optimization of stent therapy. The concept of high-pressure stent implantation disseminated quickly, and larger trials demonstrated the safety of stent implantation using high pressures. IVUS has shown that in-stent restenosis is determined by the degree of intimal hyperplasia within the stent or in the stent border. In conclusion, the use of IVUS in the world is slowly increasing. Ultrasound commonly detects occult disease in patients with coronary artery disease. However, no short- or long-term studies have determined whether disease detected exclusively by ultrasound portends a worse prognosis as compared with "true normal" angiography.

Angioplasty, Balloon, Coronary↗
PubMed2000

Emergency polytetrafluoroethylene-covered stent implantation to treat coronary ruptures.

BACKGROUND: Coronary perforation is a life-threatening complication of percutaneous interventions. In the past few years, the implantation of covered stents has emerged as a strategy for treatment when the traditional conservative approach (ie, prolonged balloon inflation and reversal of anticoagulation) fails. METHODS AND RESULTS: Since May 1997 (when polytetrafluoroethylene [PTFE]-covered stents were available at our institutions), 11 of the 12 consecutive patients who had coronary ruptures that were unsuccessfully sealed with prolonged balloon inflation and reversal of anticoagulation were treated with 12 PTFE-covered stents (PTFE group). The efficacy of the PTFE-covered stent was compared with that of noncovered stents, which were used to treat 17 perforations (non-PTFE group). One patient sustained a very distal perforation that was not suitable for covered stent sealing and underwent emergency surgery. All vessel ruptures treated with PTFE-covered stent implantation were successfully sealed. The time necessary to deploy the stent was 10+/-3 minutes (range, 4 to 15 minutes). All patients but one were discharged from the hospital and had an optimal early clinical outcome. One patient underwent emergency bypass surgery and died in the intensive care unit. The occurrence of cardiac tamponade and the necessity for emergency surgery was significantly lower in the PTFE group than in the non-PTFE group. At 14+/-4 months, the 10 discharged patients had not experienced any major adverse cardiac events. CONCLUSIONS: This preliminary study supports the utility of the PTFE-covered stent for the nonsurgical treatment of vessel ruptures.

Aged↗
PubMed2000

Randomized comparison of elective stent implantation and coronary balloon angioplasty guided by online quantitative angiography and intracoronary Doppler. DESTINI Study Group (Doppler Endpoint STenting INternational Investigation).

BACKGROUND: The purpose of this study was to compare long-term outcomes of coronary stenting in all lesions (elective stenting) or only in lesions with inadequate morphological and functional results after balloon angioplasty (guided PTCA). METHODS AND RESULTS: Treatment of multivessel disease, with any lesion length and vessel size, was allowed provided that all lesions were suitable for stent implantation. Patients were randomized to elective stent implantation (n=370) or guided PTCA (n=365). An optimal PTCA result (residual diameter stenosis </=35%, coronary flow reserve measured with a Doppler guidewire >2.0, absence of threatening dissections) was achieved in 166 lesions (43%). The remaining 218 lesions underwent stent implantation (provisional stenting). Final residual diameter stenosis was lower in the elective and provisional stent groups (9.3% and 10.2%) than in the optimal PTCA group (24.8%, P:<0. 00001). On an intention-to-treat analysis, the probability of >/=1 major adverse cardiac event at 12 months was 17.8% in the elective stenting group and 18.9% in the guided PTCA group (20.1% for optimal PTCA and 18.0% for the provisional stenting subgroup, P:=NS). The incidence of repeat target lesion revascularization at 1 year was 14. 9% in the elective stent group and 15.6% in the guided PTCA group (17.6% for optimal PTCA and 14.1% for the provisional stenting subgroup, P:=NS). CONCLUSIONS: When balloon angioplasty is guided by online quantitative angiography and Doppler-derived coronary flow reserve, with provisional stenting reserved for suboptimal results, early and late clinical outcomes are comparable to those achieved by elective stenting of all patients.

Angiography↗
PubMed2000

Polytetrafluoroethylene-covered stent for the treatment of narrowings in aorticocoronary saphenous vein grafts.

We compared the outcome of patients with saphenous graft disease treated with polytetrafluoroethylene (PTFE)-covered stents or noncovered stents. Angiographic success was similar; non-Q-wave myocardial infarction was lower in the PTFE group (p = 0.06) and long-term major cardiac events and restenosis rate were similar in the 2 groups. Implantation of PTFE-covered stent in vein graft disease seems to reduce the occurrence of distal embolization.

Aged↗
PubMed2000

Edge restenosis after implantation of high activity (32)P radioactive beta-emitting stents.

BACKGROUND: A high restenosis rate has been reported at the edges ("edge restenosis") of (32)P radioactive stents with an initial activity level of 3 to 12 microCi. This edge effect might be due to balloon injury and to a low dose of radiation at the stent margins. The aim of this study was to evaluate whether the implantation of (32)P radioactive stents with a higher activity level (12 to 21 microCi) combined with a nonaggressive stent implantation strategy could solve the problem of edge restenosis. METHODS AND RESULTS: We compared the results of lesions treated with single radioactive BX stents with an activity of 12 to 21 microCi (group 2, n = 54 lesions) with the results of lesions treated by single radioactive BX stents with an initial activity level of 3 to 12 microCi (group 1, n = 42 lesions). There were no procedural events. At the 6-month follow-up, no myocardial infarctions, deaths, or stent thromboses had occurred. Intrastent binary restenosis was 0% in group 1 versus 4% in group 2 (n = 2, both at the ostium of the right coronary artery, P = NS). Intrastent neointimal hyperplasia was significantly lower in group 2 than in group 1. The intralesion (intrastent plus peri-stent) restenosis rate was 38% in group 1 versus 30% in group 2 (P = NS). Conclusions-Single (32)P radioactive stents with an initial activity level of 12 to 21 microCi reduced intrastent neointimal hyperplasia compared with stents of 3 to 12 microCi, but they did not solve the problem of edge restenosis, even if a nonaggressive stent implantation strategy was used.

Angioplasty, Balloon, Coronary↗
PubMed2000

Immediate and long-term results of "T" stenting for bifurcation coronary lesions.

The technique of "T" stenting, which incorporates wiring both the branches of a bifurcation lesion, dilating a balloon in the main branch during stent deployment in the side branch followed by deployment of stent in the main branch, provides excellent immediate results in terms of technical and procedural success. However, further innovations are mandated to optimize the long-term outcome, which with a restenosis rate of 63%, can be described as not encouraging.

Angioplasty, Balloon, Coronary↗