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M Vaghetti

Publications and source records attributed to M Vaghetti.

14 recordsLinked to original sources
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↗
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

Cutting balloon angioplasty for the treatment of in-stent restenosis.

The results using the Cutting Balloon for the treatment of in-stent restenosis may be superior to those of conventional percutaneous transluminal coronary angioplasty (PTCA) or even the combination of PTCA preceded by rotational atherectomy. The reasons for these possible differences are not yet well defined. The case we report suggests that the Cutting Balloon achieves a better final result than conventional PTCA, by making the tissue more amenable to being pushed outward through the stent struts.

Angioplasty, Balloon, Coronary↗
PubMed2000

Left internal mammary artery graft perforation repair using polytetrafluoroethylene-covered stents.

The increase in the use of the left internal mammary artery (LIMA) as graft of choice to the left anterior descending coronary artery for conventional and minimally invasive coronary artery bypass surgery has led to an increased incidence of LIMA pathologic lesions early after surgery. The lesion, commonly located in the body of the LIMA graft, is usually caused by mechanical injury during harvesting of the vessel. In this context, percutaneous intervention with stent implantation can be complicated by vessel rupture, which usually requires emergency surgical repair. We describe two cases of stent implantation in newly placed LIMA grafts complicated by vessel rupture, which were successfully repaired using polytetrafluoroethylene-covered stents.

Aged↗
PubMed2000

Bifurcation lesions: two stents versus one stent--immediate and follow-up results.

OBJECTIVES: The purpose of this study was to evaluate two different techniques of stent placement in bifurcation lesions. BACKGROUND: Although stent placement with dedicated techniques has been suggested to be a useful therapeutic modality for bifurcation lesions, limited information is available if stent placement on the side branch and on the parent branch provides any advantage over a simpler strategy of stenting the parent vessel and balloon angioplasty of the side branch. METHODS: Between March 1993 and April 1999, we treated a total of 92 patients with bifurcation lesions with two strategies: stenting both vessels (group B, n = 53) or stenting the parent vessel and balloon angioplasty of the side branch (group P, n = 39). Paired angiograms were analyzed by quantitative angiography, and clinical follow-up was obtained. RESULTS: Stent placement on both branches resulted in a lower residual stenosis (7.4 +/- 10.9% vs. 23.4% +/- 18.7%, p < 0.001) in the side branch. Acute procedural success was similar in the two groups (group B: 87% vs. Group P: 92%). In-hospital major adverse cardiac events (MACE) occurred only in group B (13% vs. 0%, p < 0.05). At the six-month follow-up, the angiographic restenosis rate (group B: 62% vs. Group P: 48%) and the target lesion revascularization rate (38% vs. 36%, respectively) were similar in the two groups. There was no difference in the incidence of six-month total MACE (51% vs. 38%). CONCLUSIONS: For the treatment of true bifurcation lesions, a complex strategy of stenting both vessels provided no advantage in terms of procedural success and late outcome versus a simpler strategy of stenting only the parent vessel.

Aged↗
PubMed2000

Progressive decrease of outflow gradient and septum thickness after percutaneous alcoholization of the interventricular septum in hypertrophic obstructive cardiomyopathy.

BACKGROUND: The aim of this study was to evaluate the immediate- and mid-term results of percutaneous transluminal septal myocardial ablation (PTSMA) of the interventricular septum performed in 15 consecutive patients with hypertrophic obstructive cardiomyopathy between 1996 and 1999. METHODS: Prior to intervention, all patients (7 males, 8 females, mean age 62 +/- 11 years) complained of severe dyspnea (NYHA functional class III-IV) despite medical treatment with beta-blockers and/or verapamil. Family history of hypertrophic cardiomyopathy was present in 2 cases. Dehydrated alcohol (4.8 +/- 1.5 ml/pt) was selectively infused into the first septal perforator artery through over-the-wire balloon catheters. In 5 patients a second or a third septal branch was treated because the intraventricular gradient persisted above 50 mmHg after the initial alcohol infusion. RESULTS: Alcohol infusion induced an average peak creatine phosphokinase level of 1,524 +/- 427 IU/l. No iterating ventricular arrhythmias occurred during the procedure or in the 2-3 days of continuous ECG monitoring after the procedure. Two patients (13%) developed a complete atrioventricular block after the procedure, requiring permanent double-chamber pacing. Electrocardiographic changes included a > 2 mm ST segment elevation and transient right bundle branch block or left anterior/left posterior hemiblock in all patients. Peak basal intraventricular gradient decreased from 80 +/- 27 to 24 +/- 27 mmHg (p < 0.01) during cardiac catheterization and from 81 +/- 27 to 35 +/- 25 mmHg (p < 0.01) at the echocardiographic control performed during the hospital stay. At follow-up (mean 5.1 +/- 3.6 months), all patients were in NYHA functional class I or II. Repeat echocardiography showed a further significant decrease in intraventricular gradient to 25 +/- 26 mmHg (p < 0.01) and a progressive decrease in intraventricular septum thickness (25 +/- 5 mm before treatment, 21 +/- 6 mm before hospital discharge, 17 +/- 3 mm at follow-up, p < 0.01). CONCLUSIONS: PTSMA of the intraventricular septum effectively relieves symptoms in selected patients with hypertrophic obstructive cardiomyopathy. The immediate decrease in intraventricular gradient is followed by a further decline at follow-up with a progressive reduction in the intraventricular septum thickness.

Aged↗
PubMed2000

Effectiveness and complications of vascular access closure devices after interventional procedures.

BACKGROUND: Vascular closure devices are designed to obtain a fast hemostasis of the vascular access site after diagnostic and interventional procedures. This result should be obtained with a low incidence of complications. METHODS: A retrospective, non-randomized study was performed to evaluate the success rate and vascular complications associated with the use of two different vascular sealing devices [Angio-Seal (Daig Corporation, Minnetonka, Minnesota) and Prostar (Perclose, Inc., Redwood City, California)] after interventional procedures. RESULTS: Eight-hundred and twenty-seven devices were used (245 Angio-Seal and 582 Prostar). Angio-Seal success rate was 92% with a 2.5% rate of vascular complications; Prostar success rate was 89% with a 3.4% rate of vascular complications. Multivariate logistic regression analysis identified advanced age (p < 0.05) and lower weight (p < 0.05) as independent predictors of vascular complications associated with Angio-Seal use, while diabetes (p < 0.05) was found to be a predictor of vascular complications in the Prostar group. Abciximab use and larger sheath size were not associated with an increased probability of vascular complications. CONCLUSION: Angio-Seal and Prostar obtain a fast vascular access hemostasis after interventional procedures, with a low incidence of major vascular complications.

Angioplasty, Balloon, Coronary↗
PubMed2000

Coronary stenting beyond standard indications. Immediate and follow-up results.

BACKGROUND: Coronary stent has become an accepted treatment modality for selected indications. However, the literature shows diverse results when indications for coronary stenting are different from those tested in large randomized trials. The purpose of this study was to determine immediate and follow-up clinical and angiographic results in patients treated with coronary stenting for indications not specifically tested in large randomized trials. METHODS: Coronary stents were implanted in a total of 2060 lesions (1757 patients) in seven groups with expanded indications: left main coronary lesions, calcified lesions, small vessels (< 3 mm in size), small vessels with diffuse disease, large vessels with diffuse disease, and bifurcation lesions treated with stents in both branches or with one stent implanted only in the major branch. Stents were implanted using high balloon pressure for final inflation and in most cases with intravascular ultrasound. Clinical follow-up was achieved in 96% of patients at a mean time of 12+/-7 months. RESULTS: Primary success (range 89-96%) and acute complications (range 5.7-13%) were comparable in all groups. At follow-up, the mortality rate was highest in the group of left main stenting (12.5%) but 20% of these patients had coronary stenting on non-elective basis. The restenosis rates ranged between 16-43%. The restenosis rate was highest in the group of bifurcation lesions with stent implantation in both vessels leading to a major adverse cardiac event (MACE) rate of 62% in this group. However, the survival rate at 1 and 2 years in the overall study group was 97 and 96%, and the event free survival was 76 and 74%, respectively. The procedure-related predictors of MACE were: final intravascular ultrasound result, use of stents with non-slotted tube morphology, final stent percent stenosis, and vessel size. CONCLUSIONS: Coronary stenting beyond standard indications is feasible, with acceptable primary success and complication rates. However, the overall MACE rates were relatively high (34-62%), in particular for the indication of bifurcation lesions with stents implanted in both vessels.

Age Factors↗
PubMed2000

Surgical and percutaneous myocardial angiogenesis induction. Part I--laser revascularization.

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 in a subset of patients with angina refractory to medical treatment. Bypass surgery may not be feasible because of lack of suitable conduits, diffuse coronary artery disease or poor distal run-off, and coronary angioplasty is sometimes not applicable due to chronic total occlusion, diffuse disease or extreme tortuosity. Transmyocardial laser revascularization and the stimulation of neoangiogenesis by a variety of growth factors have recently emerged as a new tool in the management of these patients. In the first part of this article, we review laser-induced direct myocardial revascularization, its indications, potential risks, and published clinical trials. The induction of neoangiogenesis using different growth factors or the genes encoding for them will be the subject of the second part of our review.

Angina Pectoris↗
PubMed1999

Comparison of immediate and follow-up results of the short and long NIR stent with the Palmaz-Schatz stent.

The intrinsic characteristics of a stent including stent length may affect both procedural success and long-term outcome. The present study evaluated the immediate and follow-up results after implantation of the short and long NIR stent and compared these results with the Palmaz-Schatz stent. Between July 1995 and December 1996, stenting with a 16-mm NIR stent (NIR-16), a 32-mm NIR stent (NIR-32), or a Palmaz-Schatz stent (PS) was performed in 68, 57, and 155 lesions, respectively. There were no significant differences in the incidences of delivery failure (PS, 2.6%: NIR-16, 4.4%; NIR-32, 5.3%; p = NS) and procedural success (PS, 92%; NIR-16, 93%; NIR-32, 93%; p = NS) among the 3 groups. The reference vessel diameter was smaller in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz stent (PS, 3.14+/-0.58, NIR-16, 3.00+/-0.50; NIR-32, 2.90+/-0.47 mm; p <0.05). The lesion length was longer in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz or a 16-mm NIR stent (PS, 8.9+/-5.0; NIR-16, 11.0+/-4.1; NIR-32, 26.1+/-9.7 mm; p <0.01). After the procedure, the lesions with a 32-mm NIR stent had a smaller minimal lumen diameter than those with a Palmaz-Schatz stent (PS, 3.17+/-0.61; NIR-16, 2.99+/-0.51; NIR-32, 2.89+/-0.49 mm; p <0.01). At follow-up, a smaller minimal lumen diameter was observed in lesions with a 32-mm NIR stent than in those with a Palmaz-Schatz or a 16-mm NIR stent (PS, 2.32+/-0.98; NIR-16, 2.25+/-0.80; NIR-32, 1.68+/-0.79 mm; p <0.01). Restenosis rates were 16.5% in lesions with a Palmaz-Schatz stent, 13.3% in those with a 16-mm NIR stent, and 47.4% in those with a 32-mm NIR stent (p <0.01). Although stent delivery and procedural success of a long NIR stent were acceptable, the restenosis rate of a long NIR stent was high compared with a short NIR stent or a Palmaz-Schatz stent.

Adult↗
PubMed1999

Administration of protamine after coronary stent deployment.

BACKGROUND: Prompt reversal of anticoagulation by protamine administration could be an important therapeutic option to treat serious procedural complications such as vessel rupture or major bleeding from the puncture site during coronary stent implantation. However, this therapeutic option is rarely used because of the possible risk of stent thrombosis. METHODS: We retrospectively analyzed the incidence of acute and subacute stent thrombosis and vascular complications in 90 patients who received protamine (protamine group) and 1763 patients who did not receive protamine (control group) after successful coronary stent implantation. The 2 groups were matched for clinical, angiographic, and procedure characteristics. RESULTS: No patients in the protamine group had adverse effects such as hypotension or vascular collapse during protamine administration. Acute stent thrombosis did not occur in any protamine group patient but did occur in 12 patients in the control group (0.7%) (P =.47). Subacute stent thrombosis occurred in 2 patients in the protamine group (2.1%) and in 15 in the control group (0.8%) (P =.20). By logistic regression analysis, protamine was not a determinant of stent thrombosis. CONCLUSIONS: Reversal of anticoagulation by protamine after stent implantation does not predispose to stent thrombosis. This result has important clinical consequences because it allows the use of protamine in the treatment of coronary perforation and serious bleeding complications that may occur during coronary stent deployment.

Aged↗
PubMed1998

Coronary collateral circulation behaviour and myocardial viability in chronic total occlusion treated with coronary angioplasty.

AIMS: We explored the role of microcirculation integrity following the chronic occlusion of an infarct-related artery to assess the behaviour of collateral circulation during and after reperfusion by coronary angioplasty METHODS AND RESULTS: Eighteen patients with a proximally occluded left anterior descending artery and firm evidence of intercoronary collateral circulation were studied with selective coronary angiography and selective intracoronary myocardial contrast echocardiography, before coronary angioplasty, and at 5 and 15 min and 12 h later. Myocardial enhancement during myocardial contrast echocardiography was evaluated with a semiquantitative score (0-3), which was correlated to basal and 6 months' regional left ventricular wall motion results. 16/18 procedures were successfully performed; four patients with an inadequate acoustic window were excluded. Restenosis was evident at the 6 months' follow-up in two patients. Basal myocardial contrast echocardiography indicated that 81/192 segments from the left anterior descending coronary artery and 90/192 from the right coronary artery were perfused; no perfusion was observed in 21 segments either before or after coronary angioplasty. After coronary angioplasty, the angiographic intercoronary collateral circulation immediately disappeared, and myocardial contrast echocardiography revealed that there was a progressive reduction of segments perfused by the right coronary artery and an increase in segments perfused by the left anterior descending coronary artery. Regional left ventricular wall motion analysis demonstrated that there was abnormal motion in 51/192 segments. There was no improvement in segments with score 0 and abnormal motion after 6 months (100% sensitivity), but 16/17 segments with score 3 did show an improvement (98% specificity). The predictive value of intermediate scores (1-2) in detecting long-term improvement, was only 43%. CONCLUSION: These data show that the adaptive mechanism observed in the behaviour of epicardial and microvascular circulation after reperfusion of a chronic occluded infarct-related artery can vary. In addition, this study clearly shows that microvascular integrity detected by myocardial contrast echocardiography can provide myocardial viability.

Aged↗
PubMedDate not supplied

Short- and intermediate-term results of (32)P radioactive beta-emitting stent implantation in patients with coronary artery disease: The Milan Dose-Response Study.

BACKGROUND: Radioactive (32)P beta-emitting stents have been shown to reduce intrastent neointimal hyperplasia in a substantial dose-related manner in the animal model. The aim of this dose-response study was to evaluate, in the clinical setting, the safety and efficacy at 6-month follow-up of this approach to reducing restenosis. METHODS AND RESULTS: A total of 122 (32)P radioactive beta-emitting stents (initially the Palmaz-Schatz and later the BX Isostent) with an activity level of 0.75 to 3.0 microCi (group 1), 3.0 to 6.0 microCi (group 2), and 6.0 to 12.0 microCi (group 3) were implanted in 91 lesions in 82 patients. There were no procedural events. At 6-month follow-up, no deaths had occurred, and only 1 patient had stent thrombosis. Pure intrastent binary restenosis was 16% in group 1, 3% in group 2, and 0% in group 3. However, intralesion restenosis was 52% in group 1, 41% in group 2, and 50% in group 3. CONCLUSIONS: The use of (32)P radioactive beta-emitting stents in patients with CAD is feasible. At 6-month follow-up, intrastent neointimal hyperplasia was reduced in a dose-related manner. However, in the 3 groups, intralesion restenosis was high because of a high late lumen loss in the reference segments at the stent edges, possibly as a result of a low activity level of radiation at the edges of the stent combined with an aggressive approach to stenting. We called this "edge effect" the "candy wrapper."

Analysis of Variance↗