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S De Servi

Publications and source records attributed to S De Servi.

At least 19 recordsLinked to original sources
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↗
PubMed2001

Increased concentrations of inflammatory mediators in unstable angina: correlation with serum troponin T.

OBJECTIVE: To measure plasma interferon gamma, monocyte chemotactic protein-1 (MCP-1), and interleukin 6 and to assess their correlation with cardiac troponin T in unstable angina. DESIGN: Blood sampling in patients undergoing coronary arteriography for known or suspected ischaemic heart disease. PATIENTS: 76 patients divided in three groups: 29 with unstable angina (group 1), 28 with stable angina (group 2), and 19 without ischaemic heart disease and with angiographically normal coronary arteries (group 3). MAIN OUTCOME MEASURES: Plasma interleukin 6, interferon gamma, MCP-1, and troponin T in the three groups of patients. RESULTS: Interleukin 6 was increased in group 1 (median 2.19 (range 0.53-50.84) pg/ml) compared with the control group (1.62 (0.79-3.98) pg/ml) (p < 0.005), whereas interferon gamma was higher in group 1 (range 0-5.51 pg/ml) than in the other two groups (range 0-0.74 pg/ml and 0-0.37 pg/ml; p < 0.005 and p < 0.001, respectively). Patients with unstable angina (group 1) and positive troponin T had higher concentrations of interferon gamma than those with negative troponin T (0-5.51 pg/ml v 0-0.60 pg/ml, p < 0.001). Plasma MCP-1 was also higher in group 1 (median 267 (range 6-8670) pg/ml) than in the other two groups (134 (19-890) pg/ml and 84.5 (5-325) pg/ml; p < 0.005 and p < 0.001, respectively), and among group 1 patients with a positive troponin T assay than in those with normal troponin T (531 (14.5-8670) pg/ml v 69 (6-3333) pg/ml; p < 0.01). There was no difference in plasma interleukin 6 in group 1 patients between those with and without raised troponin T. CONCLUSIONS: The inflammatory cytokines interferon gamma and MCP-1 are increased in patients with unstable angina, particularly in those with raised concentrations of troponin T, suggesting that they are probably related to myocardial cell damage or to plaque rupture and thrombus formation.

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

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

Plasma levels of interleukin 2, 6, 10 and phenotypic characterization of circulating T lymphocytes in ischemic heart disease.

The purpose of this study was to assess lymphocyte receptors expression in patients with ischemic heart diseases, as well as to measure the plasma levels of interleukin (IL) 2, 6 and 10. T Lymphocytes are found in large numbers in human atherosclerotic plaques, indicating that immune and inflammatory mechanisms are important factors in the pathogenesis of atherosclerosis. Recent data have also implicated T lymphocytes in the pathogenetic mechanism of unstable angina and ischemic heart disease. Three groups of patients were studied: 42 with an acute ischemic syndrome (AIS), 36 with stable angina (SA) and 39 healthy controls. To characterize lymphocyte phenotype, flow cytometry was performed in whole-blood samples. IL-2, IL-6 and IL-10 were measured using the ELISA method. Double fluorescence evaluation showed an increase in CD8+/CD11b+ cells (cytotoxic T lymphocytes) and in CD11b+/CD16+CD56+ cells (NK lymphocytes) in the AIS group and in SA group as compared to the control group (P < 0.05 and P < 0.001, respectively). IL-2 was increased in the AIS and SA groups compared to the control group (AIS 4.5 +/- 0.5 pg/ml; SA 6.3 +/- 0.6 pg/ml; controls 2.4 +/- 0.8 pg/ml, P < 0.05), whereas IL-6 was higher in the AIS group than in the other two groups (AIS 10.8 +/- 1.8 pg/ml; SA 1.8 +/- 0.8 pg/ml; controls 1.2 +/- 0.6 pg/ml, P < 0.0001). These data show that patients with ischemic heart disease have an increase in circulating cytotoxic T lymphocytes and in IL-2 plasma levels, irrespective of their clinical presentation, compared to normal control subjects, whereas IL-6 is elevated only in patients with AIS.

Angina Pectoris↗
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

Increased expression of CD11b/CD18 on phagocytes in ischaemic disease: a bridge between inflammation and coagulation.

The aim of this study was to assess the expression of CD11b/CD18 integrin adhesion molecules on the phagocytes of patients with ischaemic diseases, and to evaluate the concentration of soluble adhesion molecules that are released from endothelium (sICAM-1) and from phagocytes (sL-selectin). A total of 370 patients were enrolled: 120 with coronary artery disease (CAD); 50 with peripheral artery occlusive disease (PAOD); and 200 control subjects with no clinical manifestations of ischaemic disease. CD11b/CD18 integrin was detected by flow cytometry, whereas sL-selectin and sICAM-1 concentrations were detected using a sandwich-type immunoassay. CD11b/CD18 integrin expression was found to be higher in the patients with ischaemic disease than in the control subjects (P < 0.001). The PAOD patients had higher values of CD11b/CD18 integrin than the CAD ones (P < 0.01). The concentration of soluble adhesion molecules did not show any significant differences within the three groups (P = NS). The high expression of CD11b/CD18 integrin in ischaemic disease patients may depend on the increased, but probably stable, cytokine network that has been demonstrated to occur in chronic ischaemic diseases: the difference observed between PAOD and CAD patients could be the consequence of higher inflammatory activation probably resulting from the greater extent of the atherosclerotic process in PAOD, or of the more localized ischaemic area in CAD patients. CD11b/CD18 can therefore be considered a marker of chronic phagocyte activation during ischaemic disease. On the other hand, sICAM and sL-selectin concentrations were found to be within the normal range; they have recently been considered as a marker for acute ischaemic events and acute inflammatory process activation. Our results confirm that in uncomplicated atherosclerosis no acute inflammatory process activation should occur.

Blood Coagulation↗
PubMed1997

Factors affecting the therapeutic choice in patients with multivessel coronary artery disease. The Studio Lombardo Angiografia Multivasali (SLAM) Study Group.

OBJECTIVE: To assess how clinical and angiographic findings are related to the decision to carry out coronary angioplasty (PTCA) or coronary bypass grafting in patients with multivessel coronary artery disease. DESIGN: Prospective survey carried out in 14 centres in the Lombardia region of Italy. PATIENTS: 1468 consecutive patients under going coronary arteriography for known or suspected ischaemic heart disease between May and October 1994, who were found to have multivessel coronary artery disease. MAIN OUTCOME MEASURES: Multivariate analysis was undertaken using stepwise logistic regression to identify the clinical and angiographic variables correlated with revascularisation (v medical treatment) in all of patients, and with surgery (v angioplasty) in the subset of revascularised patients. RESULTS: In all patients the clinical decision after coronary arteriography was made by physicians of each participating centre on the basis of their experience and clinical judgment: 53% of patients had bypass surgery, 28% had PTCA, and 19% continued medical treatment. The choice of a revascularisation procedure was directly related to a clinical diagnosis of unstable angina (P < < 0.001), the presence of left anterior descending artery disease (P < < 0.001), and to an ejection fraction > or = 40% (P < < 0.001), and inversely related to history of previous coronary bypass surgery (P < < 0.001). In revascularised patients, bypass surgery was the preferred treatment in patients with left anterior descending artery disease (P < < 0.001), three-vessel disease (P < < 0.001), and in those with at least one occluded vessel (P = 0.008). The choice of PTCA was significantly related to history of previous PTCA (P < < 0.001) or coronary bypass surgery (P < < 0.001), to a clinical diagnosis of non-Q wave myocardial infarction (P = 0.002), and to the possibility of implanting an intracoronary stent (P = 0.01). CONCLUSIONS: Bypass surgery is still the most widely used treatment for patients with multivessel coronary artery disease. This analysis provides a basis for comparison with future developments in the treatment of such patients. Further advancements in PTCA technology are needed to tilt the balance in favour of this less invasive procedure.

Adult↗
PubMed1997

[Coronary angioplasty: use and cost].

OBJECTIVES: The goal of the study was to examine the utilization of cardiac catheterization laboratory resources in surgical procedures in order to determine the cost impact of introducing new devices such as stents and atherectomy. METHODS: Detailed resource utilization and costs of each cardiac catheterization laboratory procedure performed in 1995 were determined. Costs were analyzed for single-vessel and multivessel coronary angioplasty, also taking into account the additional costs for coronary stent placement or for the use of directional atherectomy. RESULTS: The mean cost of a surgical procedure was ITL 8,280,010, while the mean cost for conventional coronary angioplasty was ITL 4,352,427 (ITL 4,293,108 for single-vessel PTCA; ITL 5,072,841 for multivessel PTCA). The mean cost for a procedure with stent implantation was ITL 10,084,563. As compared to conventional angioplasty, coronary stenting had a 131.6% higher catheterization laboratory cost and an additional cath-lab resource utilization in terms of contrast medium (257 +/- 136 ml vs 216 +/- 109 ml, p = 0.018) and balloon catheter (1.97 +/- 1.27 vs 1.54 +/- 0.78, p = 0.0009). The cost for a directional atherectomy followed by stent placement was ITL 18827545, which is 332.5% higher than the cost of a conventional angioplasty. CONCLUSIONS: Coronary stents and directional atherectomy have a significant economic impact on catheterization laboratory resource utilization and costs. This aspect should be taken into consideration in analyzing the short- and long-term results of these techniques.

Angioplasty, Balloon, Coronary↗
PubMed1996

Interaction between exercise training and ejection fraction in predicting prognosis after a first myocardial infarction.

BACKGROUND: Although recent meta-analysis trials have shown that exercise training may improve survival after myocardial infarction, the mechanism of this beneficial effect is still unknown. The purpose of this study was to detect possible interactions between exercise training and predictors of prognosis after a first myocardial infarction. METHODS AND RESULTS: Patients with uneventful clinical courses after a first myocardial infarction were randomly assigned to a 4-week training period (125 patients, group 1) or to a control group (131 patients, group 2). Before randomization, all patients underwent a symptom-limited exercise test (28 +/- 2 days after myocardial infarction), 24-hour Holter monitoring, and coronary arteriography (31 +/- 3 days after the acute episode). After a mean follow-up period of 34.5 months, 18 patients had cardiac deaths (5 in group 1 and 13 in group 2). Multivariate analysis by Cox regression model showed that ejection fraction was the only independent prognostic indicator (P = .03). Evidence existed of an interaction between ejection fraction and exercise training, showing an effect of physical training on survival that depended on the patient's ejection fraction. Among patients with ejection fractions < 41%, the relative risk for an untrained patient was 8.63 times higher than for a trained patient (P = .04), whereas for ejection fractions > 40%, the estimated risks for trained and untrained patients were similar. CONCLUSIONS: These data show that exercise training may prolong survival in post-myocardial infarction patients with depressed left ventricular function. A randomized trial in such patients seems warranted.

Adult↗
PubMed1996

Correlation between clinical and morphologic findings in unstable angina.

This study was undertaken to verify the hypothesis that the discrepant findings in published reports on the prevalence of thrombus in unstable angina depend on the inclusion of different clinical subsets in the various studies. We therefore correlated the clinical characteristics of patients included under the label of unstable angina with the morphologic features assessed by coronary angiography and intravascular ultrasound, and with histopathologic findings of atherectomy specimens. Fifty-eight patients with unstable angina (class B of the Braunwald classification) undergoing coronary arteriography followed by either coronary angioplasty (n = 20) or directional coronary atherectomy (n = 38) were studied. Fifteen patients were in class IB and 43 were in class II to IIIB. Among these 43 patients with angina at rest, 28 had ST-segment elevation during pain, and 15 had ST-segment depression, and 26 developed negative T waves on the baseline electrocardiogram (ECG) as a result of prolonged or repeated episodes of resting chest pain. Intravascular ultrasound examination of the culprit lesion was performed in 43 patients before the interventional procedure, and histopathologic analysis of atherectomy specimens was performed in 38 patients. Complex lesion morphology by angiography was observed in 31 patients (53%) without any significant relation to various clinical subsets. Patients in Braunwald class IB had more calcific plaques than patients in class II to IIIB (p < 0.001). Among patients with angina at rest, those with negative T waves on the baseline ECG, as well as those with transient ST elevation during pain, had a significantly higher incidence of noncalcific lesions (p = 0.001 for both). Analysis of atherectomy specimens revealed acute coronary lesions (thrombus and/or intraplaque hemorrhage) in 18 patients (47%). The incidence of acute coronary lesions was significantly higher in patients with than without negative T waves on the baseline ECG (p = 0.005), and increased further when negative T waves were combined with ST elevation during pain (p = 0.001). Multivariate analysis revealed that the presence orf negative T waves on the baseline ECG was the only explanatory variable related to the presence of acute coronary lesions by histology (p = 0.03). Patient subsets included in the broad spectrum of unstable angina have different morphologic features and incidence of acute coronary lesions by histology. These data provide an explanation for the discrepant findings in published reports on the relevance of thrombus formation in the pathogenesis of unstable angina.

Angina, Unstable↗
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↗
PubMed1996

[Evaluation of efficacy and mechanism of action of angioplasty and directed atherectomy assisted by intravascular ultrasonography].

Intravascular ultrasound (IVUS) is a unique method of coronary lumen visualization enabling also examination the structure of the artery wall. Aim of this study was to assess efficacy and mechanisms of action of balloon angioplasty (PTCA) and directional atherectomy by means of IVUS. IVUS examination was performed before and after mechanical revascularization procedure in 37 pts (DCA-19 pts, PTCA-18 pts). Both PTCA and DCA resulted in enlargement of the coronary artery lumen (2.29 +/- 1.19 mm2 vs 2.93 +/- 1.55 mm2) but, also external diameter of the vessel increased after the procedure (1.94 +/- 1.10 mm2 and 0.74 +/- 1.01 mm2 retrospectively). In 55.6% of cases after PTCA plaque rupture or artery wall dissection was observed, mainly in eccentric lesions (70%). IVUS allowed to recognize details of artery lumen and define efficiency of procedure. In about 15% cases decision to continue PTCA or DCA was made on the basis of IVUS images only. The mechanism in which PTCA modifies the artery lumen is diverse and depends on the structure of lesion. Factors possibly responsible for enlargement of the lumen are: stretching, squeezing and translocation of atheroma as well as cracking and dissections along the arterial wall. DCA effectiveness depends on the withdraw of the atheromatous deposit, however, in over one-half of cases also stretching has some effect.

Aged↗