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S Repetto

Publications and source records attributed to S Repetto.

At least 19 recordsLinked to original sources
PubMed2004

A stochastic approach for the apodization of very short arrays.

The problem addressed in this paper is the synthesis of the weight coefficients to be assigned to the elements of a linear array that has a spatial aperture shorter than one wavelength. The aim is to obtain a data-independent beam pattern that fulfills some a priori fixed constraints. The analytical approach, expressed in terms of a linear least-squares problem, has been attempted, resulting in very large noise sensitivity and beam pattern instability. To overcome this problem a mixed methodology, based on a combination of a stochastic technique and a local descent method that provides very robust weight coefficients with reduced noise sensitivity, is proposed. Here, robust means that, even if unavoidable fluctuations occur in the transducer gains, the beam pattern obtained maintains the desired features.

Journal Article↗
PubMed2003

Electron paramagnetic resonance and ultraviolet/visible study of compounds I and II in the horseradish peroxidase-H(2)O(2)-silk fiber reaction system.

The enzymatic oxidation of silk with H(2)O(2) in the presence of horseradish peroxidase (HRP) has been investigated. Two intermediate complexes have been observed during this reaction. Both can be attributed to Fe(4+) ions axially bonded to an oxygen atom and to a porphyrin radical (P). In the most unstable of them, indicated as compound II, the chemical bond between [Fe(IV)=O](2+) and P was weaker than in the other, indicated as compound I. The former compound disappeared within 1 h of the reaction, at difference with the latter, traces of which were observed even after 3 weeks with dried samples. However, the chemical bond between [Fe(IV)=O](2+) and P in compound I weakened during the sample ageing. All these phenomena have been enlightened by electron paramagnetic resonance (EPR) and spectrophotometric ultraviolet/visible (UV/Vis) measurements.

Electron Spin Resonance Spectroscopy↗
PubMed2001

Complete or incomplete percutaneous coronary revascularization in patients with unstable angina in stent era: Are early and one-year results different?

The aim of our study was to evaluate the impact of a strategy of incomplete revascularization by PTCA, with or without stent implantation, on clinical outcome of 208 consecutive patients (171 men) with unstable angina and multivessel coronary artery disease. Mean age of the group was 63.8 +/- 10.3 years (range, 31-91). Complete and incomplete revascularization was achieved in 49 and 159 patients, respectively. A total of 226 stents were implanted in 172 patients (1.31 +/- 0.65 stent per patient), equally distributed between the two groups. Left ventricular ejection fraction < 40% and total chronic coronary occlusions were significantly more frequent in patients with incomplete revascularization than in those with complete (P = 0.014 and 0.001, respectively). In-hospital MACE occurred in 10% and 7.5% of patients with complete and incomplete revascularization, respectively (P = NS). By multivariate analysis, multiple stent implantation (OR, 5.44; 95% CI, 1.21-24.3), presence of thrombus in the treated lesion (OR, 6.3; 95% CI, 1.53-25.9), Braunwald class III (OR, 4.74; 95% CI, 1.08-20.8), and ad hoc PTCA (OR 4.51; 95% CI, 1.11-18.3) were significantly related to in-hospital outcome. At 1-year follow-up, 11.3% and 11.5% of patients with complete and incomplete revascularization, respectively, had MACE. In all patients, diabetes (OR, 3.40; 95% CI, 1.09-10.58) and presence of thrombus in the treated lesion (OR, 3.48; 95% CI, 1.12-10.84) were significant predictors of 1-year outcome by multivariate analysis. These results indicate that the strategy of incomplete revascularization in unstable angina patients with multivessel coronary disease does not expose them to a higher risk of death or other major ischemic events in comparison to those undergoing complete revascularization.

Adult↗
PubMed2000

Coronary angioplasty in patients with unstable angina: clinical, electrocardiographic and angiographic predictors of in-hospital outcome. R.OS.A.I. Study Group.

BACKGROUND: In unstable angina early coronary arteriography is frequently performed, often followed by percutaneous revascularization with liberal use of stents. We intended to study the in-hospital outcome of patients receiving this treatment. METHODS: From April 1997 to April 1998, patients submitted to coronary arteriography due to unstable angina, and with no previous myocardial revascularization, were included in a multicenter registry. RESULTS: Out of 987 patients enrolled at 14 centers, 876 (89%) had percutaneous or surgical revascularization. Coronary angioplasty was performed in 571 patients (58%); 281 (49%) had Braunwald class IIIB or C angina. Refractory or prolonged chest pain, or both, were present in 133, 217 and 85 patients, respectively, and multivessel disease in 245 patients (43%). Stenting was performed in 486/571 cases (85%), abciximab was administered to 42 patients, and ticlopidine and/or aspirin to all. A procedural success was obtained in 96.9 % of cases. In-hospital major adverse cardiac events occurred in 29/571 patients (5.1%). Pain-related ST segment depression (44% of cases) was not predictive of outcome after coronary angioplasty. In multivariate analysis prolonged plus refractory angina (p = 0.02), an ejection fraction < 0.4 (p = 0.04), multivessel disease (p = 0.01) and--with the strongest predictive value--ad hoc angioplasty (p = 0.007) and use of > 1 stent (p = 0.0008) were all independent predictors of in-hospital adverse outcome. CONCLUSIONS: Coronary angioplasty with a liberal use of stents yields a high rate of procedural success, with few in-hospital major cardiac events also in "high risk" patients.

Adult↗
PubMed1999

Increased number of caveolae and caveolin-3 overexpression in Duchenne muscular dystrophy.

Caveolae are small pockets or invaginations localized at the plasma membrane. Caveolins are the principal protein components of caveolae and play an important structural role in the formation of caveolae membranes. Here, we studied by freeze fracture and immunological techniques the spatial organization of caveolae at the muscle cell plasma membrane and the expression of caveolin-3 in Duchenne muscular dystrophy (DMD) muscle fibers. In DMD muscle, we found an increased number of caveolae at the sarcolemma that corresponds to an overexpression of caveolin-3 by immunohistochemistry and by Western blot analysis. These findings suggest a possible role for caveolae and caveolin-3 in the pathogenesis of DMD.

Adolescent↗
PubMed1999

Stent thrombosis: incidence and related factors in the R.I.S.E. Registry(Registro Impianto Stent Endocoronarico)

Although stent thrombosis has been greatly reduced by adequate stent expansion with high-pressure balloon inflations and by the use of antiplatelet drugs, this event is still frightening, as it may lead to acute myocardial ischemia resulting in acute myocardial infarction or sudden death. Therefore, the definition of factors associated with stent thrombosis may provide a better understanding of the mechanisms underlying this phenomenon and may permit us to define therapeutic strategies to further reduce its occurrence. The purpose of this study was to assess factors responsible for the occurrence of stent thrombosis after coronary stent implantation in 939 consecutive patients enrolled in the Registro Impianto Stent Endocoronarico (R.I.S.E. Study Group). Consecutive patients undergoing coronary stent implantation at 16 medical centers in Italy were prospectively enrolled in the registry. Clinical data, and qualitative and quantitative angiographic findings were obtained from data collected in case report forms at each investigator site. The study group consisted of 781 men and 158 women with a mean age of 59 yr: 1,392 stents were implanted in 1,006 lesions and expanded at a maximal inflation pressure of 14.7 +/- 3 atm. The great majority of patients (92%) received only antiplatelet drugs after coronary stenting. During hospitalization there were 45 major ischemic complications in 39 patients (4.2%): 13 events were related to acute or subacute thrombosis (1.4%). Another stent thrombotic event occurred in the first month of follow-up. On multivariate logistic regression analysis, stent thrombosis was related to the following factors: unplanned stenting (OR 3.46, 95% CI 1.65-7.23), unstable angina (OR 3.37, 95% CI 1.11-10.14) and maximal inflation pressure (OR 0.83, 95% CI 0.75-0.93). In conclusion, this registry shows that in an unselected population of patients undergoing coronary stenting, stent thrombosis occurs in less than 2% of patients and is significantly related to unplanned stent implantation, unstable angina, and maximal inflation pressure. The incidence of this phenomenon is likely to be further reduced by the use of new potent antiplatelet drugs, such as platelet glycoprotein IIb/IIIa antagonists.

Adult↗
PubMed1999

One-year outcome in multivessel coronary disease patients undergoing coronary stenting.

The purpose of this study was to assess 1-year clinical outcome of patients with multivessel coronary artery disease (CAD) who underwent coronary stenting and were prospectively enrolled in the Registro Impianto Stent Endocoronarico (RISE). Of 939 consecutive patients included in the registry, 377 patients with angiographic evidence of multivessel CAD had a 1-year clinical follow-up. All patients underwent PTCA and single or multiple stenting in at least one vessel. Angiographic optimization was usually performed by using high-pressure balloon dilation. After the procedure, continuation of aspirin (at least 250 mg/day) was recommended, whereas the use of anticoagulation or ticlopidine was determined by the physician in charge of the patient in the various centers. Major adverse cardiac events were defined as death, Q-wave or non-Q-wave myocardial infarction and target vessel revascularization. Mean age of patients (311 men, 66 women) was 60 +/- 10 years. Globally, there were 596 stents implanted (72% Palmaz-Schatz stents) in 434 vessels. In about 75% of the procedures, an inflation pressure > 12 atm was used. Angiographic success rate was 98.5%. After stenting, 77% of patients received antiplatelet treatment with ticlopidine and aspirin. During hospitalization, there were 34 major adverse cardiac events in 24 patients. At 1-year follow-up, 309 patients were alive and event-free; cumulative incidence of death, myocardial infarction, and repeat revascularization were 2.9%, 4.7%, and 10.8%, respectively. By Cox regression analysis, multiple stents implantation (HR 1.72, 95% CI 1-2.97), left anterior descending artery revascularization (HR 1.86, 95% CI 1.01-3.42), use of inflation pressure > 12 atm (HR 0.93, 95% CI 0.89-0.97), ticlopidine therapy (HR 0.41, 95% CI 0.23-0.74), and stent length (HR 1.03, 95% CI 1.01-1.05) were associated with 1-year major cardiac events. In patients with multivessel CAD undergoing stent implantation in at least one vessel, 1-year follow-up is favorable and the need for repeat revascularization procedures, based on clinical data, is lower than previously reported for conventional PTCA. Cathet. Cardiovasc. Intervent. 48:343-349, 1999.

Aged↗
PubMed1999

Left ventricular opacification by intravenous contrast echocardiography.

BACKGROUND: The present study was undertaken in order to evaluate the efficacy of the intravenous administration of Albunex in obtaining left ventricular opacification and the relationship between left ventricular opacification and pulmonary pressures and cardiac function. METHODS: Fifty-two adult patients, mostly affected by ischemic heart disease, were enrolled in the study. In 37 of these patients, a complete right heart hemodynamic study was performed after Swan-Ganz catheterization. Albunex was administered in three randomized doses (0.10, 0.15 and 0.20 ml/kg) to all the patients. Left ventricular opacification was assessed both visually and using videodensitometric analysis. RESULTS: Left ventricular opacification was obtained in 93% of all the injections and an intermediate or strong opacification was obtained in 68%, while absent opacification was observed in 6% of the injections, irrespective of the contrast dose. An incremental opacification efficacy trend was observed from the lower to the higher dose, with an intermediate or strong opacification in 58 and in 77% of 0.10 and 0.20 ml/kg injections, respectively. Irrespective of the contrast dose, an enhancement of the endocardial borders was observed in 61% of the wall segments suboptimally visualized in basal conditions. The endocardial borders enhancement was obtained in 39 and in 79% of segments using the 0.10 and the 0.20 ml/kg doses, respectively. No statistically significant differences were observed between the videodensitometric parameters obtained using the three contrast doses. Finally, a significant relationship was observed between left ventricular opacification parameters and pulmonary pressures and left ventricular functional parameters, irrespective of the contrast doses considered. CONCLUSIONS: The results we obtained demonstrate the good overall efficacy of Albunex administered intravenously in order to obtain left ventricular opacification in a clinical population of cardiac patients. Moreover, they suggest that the dosage to be used clinically should preferably be at least 0.20 ml/kg, although no significant influence of contrast dosage on videodensitometric parameters has been observed. Finally, irrespective of the contrast dosage, the magnitude of left ventricular opacification appears to be influenced by the hemodynamic status of the patient.

Adult↗
PubMed1999

Safety and feasibility of coronary stenting during rescue PTCA: in-hospital outcome.

BACKGROUND: Rescue PTCA is still a debatable procedure and the results published in the literature may not justify routine application of this strategy. AIM: To evaluate the hospital outcome of patients undergoing rescue PTCA with the aim of achieving a complete recanalization of the infarct-related artery (IRA)--residual stenosis assessed with QCA < 30% and TIMI 3 forward flow--obtained with adjuvant coronary stenting when needed. METHOD: From April 1993 to December 1997, 59 consecutive patients underwent rescue PTCA after thrombolysis failure (SK or front-loaded r-tPA, UK) within 6 hours of chest pain onset. All patients had a pre-procedure TIMI 0-1 flow. IRA was the right coronary artery in 23 cases (39%), the left anterior descending in 26 (44%), the left circumflex in 9 (15.3%) and a saphenous vein graft in 1 case (1.7%). In 2 (3.3%) patients, PTCA was not performed (impossibility of crossing the stenosis with the guide-wire). Fifteen patients (26.3%) had a successful procedure (TIMI 3 flow, residual stenosis < 30%) with lone PTCA. Forty-two patients (73.6%) had an intracoronary stent placed (Palmaz-Schatz, Micro-Stent, Multilink, IRIS III): 24 patients (57.1%) for suboptimal angiographic result (TIMI 2 flow, residual stenosis > 30%), 11 patients (26.2%) for dissection, 7 patients (16.7%) for intracoronary thrombosis. All 57 patients had a TIMI 3 flow and a residual stenosis < 30% at the end of the procedure. Mean vessel diameter was 3.22 +/- 0.4 mm, mean balloon size 3.3 +/- 0.4 mm, mean inflation pressure 12 +/- 4 atm, mean residual stenosis 8 +/- 9%. RESULTS: The overall procedure success rate was 96.6%. During hospitalization, three patients (5.1%) suffered subacute reocclusion managed conservatively in one case, with CAGB in another and with re-PTCA in the last one. Three patients (5.1%) had minor vascular complications (groin hematoma) not requiring surgical correction or blood transfusion. No patients died, suffered reinfarction or stroke. All patients were discharged alive and free of angina or clinical heart failure. CONCLUSIONS: Coronary stenting performed in the setting of rescue PTCA leads to a good procedural success rate allowing TIMI 3 flow and low residual stenosis (< 30%). Therefore, when conventional balloon angioplasty is unable to achieve an optimal angiographic result, stenting can be accomplished safely, thereby improving the procedural success rate and allowing a bright event-free survival rate.

Angioplasty, Balloon, Coronary↗
PubMed1998

Predictors of major in-hospital ischemic complications and length of hospital stay after coronary stenting.

Although recent data show that coronary stenting reduces procedural complications and late restenosis, major concern has been expressed about the greater hospital cost associated with the use of this device as compared to conventional coronary angioplasty. Since length of hospital stay after surgical procedures is a major determinant of resource use, the identification of variables associated with an excessively long hospital stay after intracoronary stent placement may have important practical consequences. The purpose of this study was to assess factors responsible for the occurrence of in-hospital complications and prolonged hospital stay after coronary stenting in 939 consecutive patients enrolled in the Registro Impianto Stent Endocoronarico (RISE Study Group). Consecutive patients undergoing coronary stent implantation at 16 medical centers in Italy were prospectively enrolled in the Registry. Clinical data, qualitative and quantitative angiographic findings were obtained from data collected in case report forms at each investigator site. Major ischemic complications were considered death, Q-wave myocardial infarction, emergency bypass surgery and emergency repeat angioplasty. The study group consisted of 939 patients (781 men, 158 women with a mean age of 59 years) in whom 1392 stents were implanted in 1006 lesions and expanded at a maximal inflation pressure of 14.7 +/- 3 atmospheres. The great majority of patients (92%) received only antiplatelet drugs after coronary stenting. During hospitalization, there were 45 major ischemic complications in 39 patients (4.2%): 13 events were related to acute or subacute thrombosis (1.4%). On multivariate logistic regression analysis, the following factors were predictive of in-hospital complications: increasing age (OR 2.19, 95% CI 1.18-4.07), unplanned stenting (OR 3.46, 95% CI 1.65-7.23) and maximal inflation pressure (OR 0.83, 95% CI 0.75-0.93). Mean hospital stay after stent implantation was 4.1 +/- 4.4 days and was related, by multivariate regression analysis, to female sex (p = 0.0001), prior bypass surgery (p = 0.03), non-elective stenting (p = 0.0001), use of anticoagulation (p = 0.0001) and development of major ischemic complications (p = 0.0001). This Registry shows that in an unselected population of patients undergoing coronary stenting, major ischemic complications occur at a relatively low rate (4.2%) and thrombotic events can be kept at 1.4%, despite the omission of anticoagulation in the great majority of patients. Length of hospital stay was affected by the occurrence of major ischemic complications, unplanned stenting, use of anticoagulation, female sex and prior bypass surgery. Accumulating experience, further reduction in complications and complete omission of anticoagulation may decrease length of hospital stay, thus reducing the use of resources after coronary stenting.

Adult↗
PubMed1997

[The Registry for Angioplasty in Infarction (RAI): brief preliminary report on the main indicators and process of acute outcome].

BACKGROUND: Emergency coronary angioplasty can be the treatment of choice in selected patients with acute myocardial infarction in centers with adequate facilities and organization. METHODS: A multicenter observational study in patients with high-risk acute myocardial infarction was conducted to evaluate the quality of emergency angioplasty treatment according to process, acute and long-term outcome, and use of resources. RESULTS: The RAI registry included 345 patients with high-risk acute myocardial infarction who were admitted to six participating centers over a thirteen-month period. Emergency coronary angiography was performed in 261 patients (76%) and was followed by immediate angioplasty in 236 of them (68%). Mean door-to-procedure time was 58 +/- 47 min. Severe left ventricular failure was present at admission in 35 (13%) of the 261 patients with emergency coronary angiography; and 29 of them were in cardiogenic shock (11%). Overall, in-hospital mortality for patients with angioplasty was 7.6%; i.e., 43% and 3.7% for patients with and without shock, respectively. CONCLUSIONS: Despite logistical limitation, in centers with emergency angioplasty programs this treatment can be performed with favorable process and acute outcome characteristics in patients with high-risk myocardial infarction.

Acute Disease↗
PubMed1996

High energy transcatheter cardioversion for chronic, poorly tolerated atrial fibrillation.

Between August 1991 and May 1993, 14 patients affected by chronic, poorly tolerated atrial fibrillation (AF) were submitted to high energy transcatheter cardioversion. Mean duration of AF was 27.4 +/- 45.1 months. In nine patients (56%), AF lasted for > 1 year. All patients had underlying heart disease, with a mean LVEF of 45.2% +/- 11.8% and a NYHA Class > or = II. Previously, a mean of 2.9 +/- 1.3 patients failed external electrical cardioversion, with and without antiarrhythmics, have been attempted. Transcatheter conversion was performed by pulling the His-bundle catheter back in the right atrial cavity until no His bundle activity was recorded on distal poles, and then delivering the shock between a proximal electrode (cathode) and a back plate (anode). In all patients, transcatheter conversion restored sinus rhythm. Transient complete atrioventricular (AV) block was observed in four patients (28%), and treated by prophylactic temporary pacing. At 1 year, seven patients (50%) were still in sinus rhythm. In this series, only younger age could be related to AF recurrence (46.1 +/- 10.8 vs 63.4 +/- 6.8 years, P < or = 0.004), even if prophylaxis with amiodarone showed a positive trend versus sinus rhythm maintenance (71% vs 14%, P = NS). In conclusion, high energy transcatheter cardioversion is a safe and effective method of restoring sinus rhythm in patients with chronic, poorly tolerated AF. In these patients, high energy transcatheter cardioversion could be considered as an alternative to AV node ablation techniques, avoiding pacemaker implant and embolic risk. Larger studies are needed to determine better patient selection and delineate drug strategy after the procedure.

Age Factors↗
PubMed1996

Stenting of the Infarct-Related Artery During Complicated Angioplasty in Acute Myocardial Infarction.

The aim of this study was to assess safety and efficacy of coronary stenting as a strategy for improving PTCA suboptimal angiographic result. From March 1993 to December 1995, 104 patients underwent PTCA during acute myocardial infarction. Unplanned coronary stenting was required in 66 pts (63.5%). Procedural success was obtained in 64 pts (97%). Two patients had an unsuccessful stenting procedure: one patient for a suboptimal stent deployment and another for LAD reocclusion requiring emergency CABG (1.5%). Palmaz-Schatz stents were used in 60 pts (91%) and AVE micro-stent in 6 pts (9%). During the hospital course, subacute reocclusion of the vessel occurred in 3 pts (4.6%); one patient underwent a successful rePTCA while the other two underwent CABG. Two patients had vascular groin complications requiring surgical repair of the femoral artery. During hospitalization, one patient underwent elective CABG for early residual myocardial ischemia. At seventy-two hours from PTCA, one patient (1.5%) died as a result of intestinal infarct. Six months survival rate was 98.3% for 59 pts discharged alive from our department. Ten pts were symptomatic during the follow-up: One patient underwent PTCA on another vessel and the other underwent CABG for a multivessel disease. CABG was used in one patient who presented residual silent ischemia in multivessel coronary artery disease. At six months, the first group of patients (18 pts) underwent planned coronary angiography: Vessel patency was present in 17 patients. One patient had an asymptomatic reocclusion of the treated vessel. This study shows a good angiographic result obtained with intracoronary stenting during primary or rescue PTCA of the infarct-related artery. It does not appear to increase major in-hospital adverse events and may reduce the need for surgical revascularization, reducing in-hospital mortality rate and favorably affecting LVEF.

Journal Article↗
PubMed1996

[Histopathologic features in atherectomy samples obtained from patient with unstable angina, stable angina and restenosis. Directional Atherectomy Lombardi Group].

BACKGROUND: The present study was aimed at investigating the pathologic features of directional coronary atherectomy (DCA) samples obtained from 194 patients (14 females) with stable (n = 68) and unstable (n = 95) angina, and with restenosis (n = 27). METHODS: DCA samples were obtained from culprit lesions, using the Simpson technique. Unstable angina was classified according to E. Braunwald criteria. Stable angina was grouped according to the presence or absence of a prior myocardial infarction (MI). DCA samples were fixed, processed, serially cut and stained with hematoxilin-eosin and with Movat pentachrome stain. RESULTS: The major pathologic findings were thrombosis, inflammation of the superficial plaque layers, and neointimal hyperplasia which often coexisted within a same sample. Their frequencies, in that order, were distributed in the differing groups of patients as follows: 21% (n = 9), 29.2% (n = 12) and 51% (n = 21) of the 41 cases with stable angina without prior MI. 40.7% (n = 11), 40.7% (n = 11), and 51.8% (n = 14) of the 27 cases with stable angina with prior MI. 25% (n = 4), 56.2% (n = 9) and 68.7% (n = 11), of the 16 cases with BI unstable angina. 35.3% (n = 14), 55.8% (n = 19) and 44% (n = 15), of the 34 cases with BII unstable angina. 44.4% (n = 4), 33.3% (n = 3) and 33.3% (n = 3), of the 9 cases with BIII unstable angina. 48.2% (n = 14), 48.2% (n = 14) and 51.8% (n = 15), of the 29 cases with CII unstable angina at 35.8 days after MI. 60% (n = 3), 60% (n = 3) and 40% (n = 2), of the 5 cases with CIII unstable angina at 8.3 days after MI. 26% (n = 7), 48% (n = 13) and 85.1% (n = 23), of the 27 cases with restenosis. According to above observation, the frequency of coronary thrombosis increases with the increase of the severity of myocardial ischemia. However, thrombosis is not found in most unstable angina without prior MI (63% of BI-II-III unstable angina cases do not have thrombus). In addition, thrombus is not a specific finding of unstable angina, given its occurrence, although in a much lower percentage of cases, in stable angina and in restenosis. CONCLUSIONS: Present data show that different ischemic and plaque lesions. This observation questions on the pathogenetic role of thrombus in unstable angina and calls for further investigations on inflammation and neointimal hyperplasia, as well as on the the reciprocal relation between these findings which are often combined within a same lesion.

Adult↗
PubMed1995

Comparison of coronary lesions obtained by directional coronary atherectomy in unstable angina, stable angina, and restenosis after either atherectomy or angioplasty.

The present study investigated the incidence of the histopathologic lesions and of growth factor expression in a consecutive series of directional coronary atherectomy (DCA) samples from 40 unstable angina pectoris patients without prior acute myocardial infarction and compared the findings with those obtained in DCA samples from 18 patients with stable angina without previous infarction and 18 patients with restenosis. We investigated coronary thrombosis, neointimal hyperplasia, and inflammation. For unstable angina, we correlated the angiographic Ambrose plaque subtypes with the histopathologic findings. The immunophenotype of plaque cells and the growth factor expression were assessed with specific antibodies for cell characterization and for the expression of basic fibroblast and platelet-derived AA and AB growth factors and receptors. The incidence of coronary thrombosis was 35% in patients with unstable angina, 17% in those with stable angina, and 11% in patients with restenosis. Neointimal hyperplasia was found in 38% of unstable angina cases, in 17% of stable angina cases, and in 83% of restenosis cases. Inflammation without thrombus or accelerated progression occurred in 20% of unstable angina and 6% of stable angina samples. In 52% of unstable angina cases, inflammation coexisted with thrombosis and/or neointimal hyperplasia. In the unstable angina group, 71% of the plaques with thrombus had a corresponding angiographic pattern of complicated lesions. The growth factor expression, reported as percentage of cells immunostaining with different growth factor antibodies, was highest in restenosis, followed by unstable angina and stable angina lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗