Angiographic findings of the multicenter Randomized Study With the Sirolimus-Eluting Bx Velocity Balloon-Expandable Stent (RAVEL): sirolimus-eluting stents inhibit restenosis irrespective of the vessel size.

BACKGROUND: Restenosis remains the major limitation of coronary catheter-based intervention. In small vessels, the amount of neointimal tissue is disproportionately greater than the vessel caliber, resulting in higher restenosis rates. In the Randomized Study With the Sirolimus-Eluting Bx Velocity Balloon-Expandable Stent (RAVEL) trial, approximately 40% of the vessels were small (<2.5 mm). The present study evaluates the relationship between angiographic outcome and vessel diameter for sirolimus-eluting stents. METHODS AND RESULTS: Patients were randomized to receive either an 18-mm bare metal Bx VELOCITY (BS group, n=118), or a sirolimus-eluting Bx VELOCITY stent (SES group, n=120). Subgroups were stratified into tertiles according to their reference diameter (RD; stratum I, RD <2.36 mm; stratum II, RD 2.36 mm to 2.84 mm; stratum III, RD >2.84 mm). At 6-month follow-up, the restenosis rate in the SES group was 0% in all strata (versus 35%, 26%, and 20%, respectively, in the BS group). In-stent late loss was 0.01+/-0.25 versus 0.80+/-0.43 mm in stratum I, 0.01+/-0.38 versus 0.88+/-0.57 mm in stratum II, and -0.06+/-0.35 versus 0.74+/-0.57 mm in stratum III (SES versus BS). In SES, the minimal lumen diameter (MLD) remained unchanged (Delta -0.72 to 0.72 mm) in 97% of the lesions and increased (=late gain, DeltaMLD <-0.72 mm) in 3% of the lesions. Multivariate predictors for late loss were treatment allocation (P<0.001) and postprocedural MLD (P= 0.008). CONCLUSIONS: Sirolimus-eluting stents prevent neointimal proliferation and late lumen loss irrespective of the vessel diameter. The classic inverse relationship between vessel diameter and restenosis rate was seen in the bare stent group but not in the sirolimus-eluting stent group.

New diagnostic criteria for diabetes and coronary artery disease: insights from an angiographic study.

OBJECTIVES: The goal of this research was to study coronary atherosclerosis in patients with type 2 diabetes compared with patients without diabetes according to the new definition of diabetes advocated by the American Diabetes Association in 1997. BACKGROUND: Patients with diabetes (fasting plasma glucose above 7.0 mM/L) have a higher risk of cardiovascular death. The correlation with the pattern and severity of their coronary atherosclerosis, especially in the new patients with "mild" diabetes (7.0 mM/L < or = fasting plasma glucose < 7.8 mM/L), remains unclear. METHODS: A cohort of 466 patients undergoing coronary angiography but free of any previous infarction, coronary intervention and insulin therapy were prospectively recruited. Ninety-three had diabetes (fasting plasma glucose > 7.0 mM/L or hypoglycemic oral treatment). Five angiographic indexes were calculated to describe severity and extent of coronary atherosclerosis. RESULTS: Overall, patients with diabetes had more diffuse coronary atherosclerosis, a greater prevalence of mild, moderate and severe stenoses and a two-fold higher occlusion rate than patients without diabetes, even after adjustment for age, gender, body mass index, hypertension, lipid parameters, smoking, family history of cardiovascular events and ischemic symptoms. Patients with "mild diabetes" had a coronary atherosclerosis pattern more similar to patients with normal fasting plasma glucose than to patients formerly defined as diabetic according to the World Health Organization criteria, except that they had a higher prevalence of <50% stenoses. CONCLUSIONS: In patients with type 2 diabetes, those with 7.0 mM/L < or = fasting plasma glucose < 7.7 mM/L have a slightly greater prevalence of mildly severe lesions that may partly explain their higher cardiovascular event rate.

Percutaneous transluminal angioplasty of the anomalous circumflex artery.

The technical experience reported in the literature concerning angioplasty in patients with anomalous origin of the left circumflex artery is limited. Balloon angioplasty seems to be a favorable approach for revascularization in these vessels, and major determinants of successful angioplasty are angiographic knowledge of their course and structure, appropriate selection of guiding catheter, and the possibility of advancing the balloon into the anomalous vessel. Five consecutive patients with severe atherosclerotic lesions on the anomalous left circumflex artery who underwent coronary angioplasty of the anomalous vessel are reported. Angiographic and clinical success were achieved in three patients with balloon alone and in one with stent implantation.

[Use of radiotherapy in cardiovascular disease. Radiophysical basis, current results, indications and perspectives]. / La curiethérapie en pathologie cardiovasculaire. Bases radiophysiques, résultats actuels, indications et perspectives.

Restenosis is the main limitation of percutaneous angioplasty, especially in vessels of small diameters such as the coronary arteries, the femoro-popliteal and tibial-peroneal arteries and the arterio-venous dialysis grafts. The extensive use of tents has not entirely prevented its occurrence, whereas treating in-stent restenosis gives even more uncertain results. Endovascular radiotherapy has emerged over the past few years as a promising approach to both prevent and cure it. The analogy between the tumour-like cellular proliferations observed in post-angioplasty restenosis and tumour processes prompted pioneering works to study the effect of ionizing radiations in animal models of arterial restenosis. The demonstrated feasibility, tolerance and efficacy of this approach lead to test this strategy in humans. The results of 3 recently presented randomized double-blind trials in the treatment of coronary in-stent restenosis have been so promising that endovascular brachytherapy might now be considered the treatment of choice in this indication. Other randomized trials are currently carried out to test whether endovascular brachytherapy may prevent restenosis in coronary and femoro-popliteal arteries as well as in hemodialysis shunts. In the present review, we describe the basics of the biological effects of ionizing radiations, the technical modalities to deliver endovascular radiations, our current knowledge about their effects on the vascular wall and the restenosis mechanisms, and the results of the first clinical studies. Finally, we address the remaining problems in the use of endovascular curietherapy and question the promises and challenges of its clinical application.

A comparison of systematic stenting and conventional balloon angioplasty during primary percutaneous transluminal coronary angioplasty for acute myocardial infarction. STENTIM-2 Investigators.

OBJECTIVES: In a multicenter, randomized trial, systematic stenting using the Wiktor stent was compared to conventional balloon angioplasty with provisional stenting for the treatment of acute myocardial infarction (AMI). BACKGROUND: Primary angioplasty in AMI is limited by in-hospital recurrent ischemia and a high restenosis rate. METHODS: A total of 211 patients with AMI <12 h from symptom onset, with an occluded native coronary artery, were randomly assigned to systematic stenting (n = 101) or balloon angioplasty (n = 110). The primary end point was the binary six-month restenosis rate determined by core laboratory quantitative angiographic analysis. RESULTS: Angiographic success (Thrombolysis in Myocardial Infarction [TIMI] flow grade 3 and residual diameter stenosis <50%) was achieved in 86% of the patients in the stent group and in 82.7% of those in the balloon angioplasty group (p = 0.5). Compared with the 3% cross-over in the stent group, cross-over to stenting was required in 36.4% of patients in the balloon angioplasty group (p = 0.0001). Six-month binary restenosis (> or = 50% residual stenosis) rates were 25.3% in the stent group and 39.6% in the balloon angioplasty group (p = 0.04). At six months, the event-free survival rates were 81.2% in the stent group and 72.7% in the balloon angioplasty group (p = 0.14), and the repeat revascularization rates were 16.8% and 26.4%, respectively (p = 0.1). At one year, the event-free survival rates were 80.2% in the stent group and 71.8% in the balloon angioplasty group (p = 0.16), and the repeat revascularization rates were 17.8% and 28.2%, respectively (p = 0.1). CONCLUSIONS: In the setting of primary angioplasty for AMI, as compared with a strategy of conventional balloon angioplasty, systematic stenting using the Wiktor stent results in lower rates of angiographic restenosis.

Geometric features of coronary artery lesions favoring acute occlusion and myocardial infarction: a quantitative angiographic study.

OBJECTIVES: We sought to identify the angiographic predictors of a future infarction, to study their interaction with time to infarction, patient risk factors and medications, and to evaluate their clinical utility for risk stratification. BACKGROUND: Identification of coronary lesions at risk of acute occlusion remains challenging. Stenosis severity is poorly predictive but other stenosis descriptors might be better predictors. METHODS: Eighty-four patients with an acute myocardial infarction and a coronary angiogram performed within the preceding 36 months (baseline angiogram), and after infarction were selected. All coronary stenoses (from 10% to 95% lumen diameter reduction) at baseline angiogram were analyzed by computer-assisted quantification. Each of the 84 lesions responsible for the infarction (culprit) was compared with the nonculprit stenoses (controls) in the same patient. RESULTS: Culprit lesions were more symmetrical (symmetry index +15%; p < 0.001), had steeper outflow angles (maximal angle +4 degrees; p < 0.001), were more severe (percent stenosis +5%; p = 0.001) and longer (+ 1.5 mm, p = 0.01) than controls. The symmetry index and the outflow angles were the two independent predictors of infarction at three-year follow-up. Stenosis severity predicted only infarctions occurring within 1 year after angiography. In moderately severe stenoses (40% to 70% stenosis), stratification using the symmetry index and outflow angles accurately predicted lesions remaining free of occlusion and infarction at three-year follow-up. CONCLUSIONS: Better characterization of stenosis geometry might help to understand the pathophysiologic mechanisms triggering coronary occlusion and to stratify patients for improved care.

[Diabetic coronary disease and risk of myocardial infarction]. / Coronaropathie diabétique et risque d'infarctus du myocarde.

The raised incidence of myocardial infarction and sudden death in diabetics was explained over 20 years ago by the increase in prevalence and severity of coronary atherosclerosis. Coronary angiographies of 820 consecutive patients admitted to hospital for coronary artery disease were analysed. One hundred and fifteen of these patients (14%) were diabetic. In 77.4% of diabetics and 72.6% of non-diabetics, coronary angiography showed coronary lesions which were usually distal and three vessel in diabetics. When the three coronary arteries were analysed globally, the percentage of patients with at least one mild stenosis was much higher in diabetics than in non-diabetics (50.6% vs 30.3% respectively, p < 0.001), but there was no statistical difference in the number of severe stenoses or occlusions. The increase in mild stenosis in the diabetic population could indicate an anatomical predisposition to future rupture of a plaque. This result could explain the increased frequency of myocardial infarction and sudden death in diabetes, not necessarily preceded clinically by angina pectoris.

Percutaneous transluminal angioplasty of radial artery grafts.

The radial artery is being used with increasing frequency to replace the saphenous vein as a coronary artery bypass graft, in the belief that it will provide improved long-term patency. Several centers have confirmed that the early results of surgery using the radial artery seem to be better than those obtained with saphenous grafts. Despite these apparent gains, early failure of the radial artery graft can occur and is frequently associated with symptomatic myocardial ischemia. Percutaneous angioplasty is an alternative to reoperation to treat lesions occurring on radial artery grafts. We report on 4 patients who underwent angioplasty of radial artery grafts.

The radial artery for coronary artery bypass grafting: clinical and angiographic results at five years.

OBJECTIVE: The aim of this study was to assess the long-term results of use of the radial artery as a conduit for coronary artery bypass grafting. METHODS: After revival of the technique in 1989, the radial artery was used as a conduit in 910 patients undergoing coronary artery bypass grafting. A complete follow-up was obtained for the first 102 consecutive patients from 4 to 7 years after the operation (mean 5.27 +/- 1.30 years). Fifty-nine percent of the patients were receiving calcium-channel inhibitors. An electrocardiographic stress test was obtained for 51 patients, with no contraindications found. Routine follow-up angiography was performed in 50 cases, including those of all patients with symptoms. Thus 64 radial artery and 48 left internal thoracic artery grafts were followed up from 4 to 7 years after the operation (mean 5.6 +/- 1.40 years). RESULTS: The actuarial survival was 91.6% at 5 years, and the actuarial rate of freedom from angina was 88.7% at 5 years. Four patients underwent percutaneous transluminal angioplasty during the period of follow-up, and there were no reoperations for revision of the bypass. The electrocardiographic stress test showed negative results in 73% of cases, electrocardiographic changes alone in 21%, and clinically positive results in 6%. Angiography showed that the patency rate of the radial artery grafts was 83%. The patency rate of the left internal thoracic artery grafts (n = 47) was 91%. The difference in patency could be related to the implantation sites of the grafts, mainly the circumflex artery (51%) for the radial artery grafts and almost exclusively the left anterior descending artery (94%) for the left internal thoracic artery. CONCLUSION: The use of the radial artery for coronary bypass grafting provides excellent clinical and angiographic results at 5 years. Routine use of the radial artery in combination with the left internal thoracic artery can be recommended.

[Left atrial myxoma and coronary embolism]. / Myxome de l'oreillette gauche et embolie coronaire.

The authors report the case of a 49 year old man referred for a preoperative evaluation of a left atrial myxoma. During the hospital admission, the patient had an episode of sudden anginal chest pain associated with electrocardiographic changes of anteroseptoapical myocardial infarction. Emergency coronary angiography showed occlusion of the middle segment of the left anterior descending artery whereas it had been absolutely normal on the coronary angiogramme performed a few days beforehand. The diagnosis of coronary embolism from the left atrial myxoma was made and an emergency coronary angioplasty was performed followed by surgical ablation of the tumour.

Relation between severity of coronary artery disease, left ventricular function and myocardial infarction, and influence of the ACE I/D gene polymorphism.

Left ventricular (LV) systolic function is partly determined by severity of coronary artery disease and is improved by angiotensin-converting enzyme (ACE) inhibition, at least in post-infarct patients. Because the ACE insertion/deletion (I/D) gene polymorphism is associated with circulating and tissue ACE activity, we sought to evaluate the role of this genetic variant on LV function in patients studied with coronary angiography, taking into account coronary vessel anatomy and history of infarction. Coronary artery disease extent scores, coronary artery patency, and LV ejection fraction were assessed in 400 consecutive Caucasian patients referred for established or suspected ischemic heart disease. A previous infarction had occurred in 141 patients an average of 3.7 years before the study. The ACE DD genotype, compared with the ACE ID/II genotype, was associated with a 2.7% higher ejection fraction in noninfarct patients (p = 0.047) but a 5.0% lower ejection fraction in post-infarct patients (p = 0.047). An interaction effect between the ACE I/D gene polymorphism, the infarction status, and LV ejection fraction was observed in the whole population (p = 0.003), in patients with no disease and 1-, 2-, and 3-vessel diseases (p = 0.03 and p = 0.06, respectively), and in those with chronically occluded coronary vessels (p = 0.02). The influence of the ACE I/D gene polymorphism on LV function is modulated by infarction status and coronary anatomy.

Sialic acid content of LDL in coronary artery disease: no evidence of desialylation in subjects with coronary stenosis and increased levels in subjects with extensive atherosclerosis and acute myocardial infarction: relation between desialylation and in vitro peroxidation.

We recently showed that sialic acid content of LDL was not a marker of early cardiovascular disease (Arterioscler Thromb Vasc Biol. 1995;15:334-339). Here, we investigated this parameter in patients with advanced coronary artery disease (CAD). We first examined 100 patients having undergone coronary angiography. The distribution of LDL sialic acid values was very similar in subjects with no coronary stenosis (31.3+/-3.7 nmol/mg LDL protein, mean+/-SD) and those with > or = 75% stenosis in at least one main coronary artery or > or = 50% stenosis in at least two main coronary arteries (32.1+/-5.5 nmol/mg LDL protein). In contrast, LDL sialic acid content was significantly increased in patients with both coronary stenosis and peripheral arterial atherosclerotic lesions compared with those with either no lesion or only one or the other type of lesion. We then examined LDL sialic acid content in 20 patients with acute myocardial infarction. LDL sialic acid content was significantly higher (35.9+/-3.2 nmol/mg LDL protein) than that in the CAD(-) control group. These data suggest that LDL sialic acid content increases with the extension of atherosclerosis and its progression to acute complications. To explain the discordance with Orekhov and coworkers (Atherosclerosis. 1991;86:153-161), who showed that LDL sialic acid content in patients with advanced CAD was lower than that in healthy subjects, we studied the time courses of sialic acid, TBARS, and vitamin E levels in LDL dialyzed in different experimental conditions. A continuous decrease in both sialic acid and vitamin E levels and an increase in TBARS levels were observed in LDL samples containing less than 1 mmol/L EDTA, the intensity and rapidity of which varied with the EDTA concentration in the buffer. Our data support the idea that desialylation may result from in vitro peroxidation of LDL.

Use of anti-GP IIb-IIIa in acute thrombosis after intracoronary stent implantation.

Acute occlusion of coronary stents still occurs in 0.5-2% of patients. The usefulness of GP IIb-IIIa receptor inhibitors has never been evaluated in this indication. After 1,454 stent implantations, acute occlusion occurred in 16 patients. Direct percutaneous transluminal coronary angioplasty (PTCA) was immediately performed. In eight patients, no recurrent thrombosis occurred during the 15 min following PTCA, and abciximab infusion was started after this period. In six patients, immediate recurrent thrombosis occurred in the stent. In these cases, an intravenous bolus of abciximab followed by a new inflation at low pressure was performed. Fifteen min after the bolus, stable TIMI 3 flow was restored in all six cases, and no thrombus or haziness remained. In two patients, a TIMI 0 flow persisted despite PTCA and the use of a bolus of abciximab. No recurrent ischemic symptoms were observed before hospital discharge. Abciximab in combination with balloon angioplasty can be used safely to control acute thrombosis after stent deployment.

First international new intravascular rigid-flex endovascular stent study (FINESS): clinical and angiographic results after elective and urgent stent implantation. The FINESS Trial Investigators.

OBJECTIVES: The purpose of this study was to determine the feasibility, safety and efficacy of elective and urgent deployment of the new intravascular rigid-flex (NIR) stent in patients with coronary artery disease. BACKGROUND: Stent implantation has been shown to be effective in the treatment of focal, new coronary stenoses and in restoring coronary flow after coronary dissection and abrupt vessel closure. However, currently available stents either lack flexibility, hindering navigation through tortuous arteries, or lack axial strength, resulting in suboptimal scaffolding of the vessel. The unique transforming multicellular design of the NIR stent appears to provide both longitudinal flexibility and radial strength. METHODS: NIR stent implantation was attempted in 255 patients (341 lesions) enrolled prospectively in a multicenter international registry from December 1995 through March 1996. Nine-, 16- and 32-mm long NIR stents were manually crimped onto coronary balloons and deployed in native coronary (94%) and saphenous vein graft (6%) lesions. Seventy-four percent of patients underwent elective stenting for primary or restenotic lesions, 21% for a suboptimal angioplasty result and 5% for threatened or abrupt vessel closure. Fifty-two percent of patients presented with unstable angina, 48% had a previous myocardial infarction, and 45% had multivessel disease. Coronary lesions were frequently complex, occurring in relatively small arteries (mean [+/-SD] reference diameter 2.8 +/- 0.6 mm). Patients were followed up for 6 months for the occurrence of major adverse cardiovascular events. RESULTS: Stent deployment was accomplished in 98% of lesions. Mean minimal lumen diameter increased by 1.51 +/- 0.51 mm (from 1.09 +/- 0.43 mm before to 2.60 +/- 0.50 mm after the procedure). Mean percent diameter stenosis decreased from 61 +/- 13% before to 17 +/- 7% after intervention. A successful interventional procedure with < 50% diameter stenosis of all treatment site lesions and no major adverse cardiac events within 30 days occurred in 95% of patients. Event-free survival at 6 months was 82%. Ninety-four percent of surviving patients were either asymptomatic or had mild stable angina at 6 month follow-up. CONCLUSIONS: Despite unfavorable clinical and angiographic characteristics of the majority of patients enrolled, the acute angiographic results and early clinical outcome after NIR stent deployment were very promising. A prospective, randomized trial comparing the NIR stent with other currently available stents appears warranted.

[A comparative study of 4 diagnostic strategies in coronary artery disease. A theoretical approach]. / Etude comparée de quatre stratégies diagnostiques de la maladie coronaire. Approache théorique.

The prognosis of patients with coronary artery disease is constantly improving mainly due to better control of risk factors, to improved methods of myocardial revascularisation and better follow-up. For effective management, the diagnosis of coronary disease has to be established. The authors used a statistical model to study the efficacy of 4 diagnostic strategies used in daily practice: (i) three investigations in two stages: exercise stress testing, stress echocardiography or stress scintigraphy followed by coronary angiography when positive (EE, ECHO, SCINTI): (ii) one stage investigation: coronary angiography of first indication (CORO). When the a priori probability is low or moderate (less than 0.5) the efficacy of EE, ECHO and SCINTI is excellent as there are few false negative results. When the a priori probability of coronary disease is high (0.7 or more), the percentage of false negative results (patients with undetected significant coronary disease) becomes very high. At this level of risk the CORO strategy avoids the false negatives without increasing the costs with respect to the other strategies. In conclusion, the choice of diagnostic strategy of coronary artery disease should take into account the "a priori" risk of the patient. When high (> 0.7), coronary angiography of first intention seems to be statistically justified.

Genetic polymorphisms of the renin-angiotensin system and angiographic extent and severity of coronary artery disease: the CORGENE study.

Genetic polymorphisms of the renin-angiotensin system (RAS) have been associated with coronary artery disease (CAD) but no relation between these polymorphisms and coronary atherosclerosis has yet been systematically evaluated. The CORGENE study is a cross-sectional study involving 463 Caucasians who underwent standardized coronary angiography for established or suspected CAD [156 patients with a previous myocardial infarction (MI), 307 without MI]. Four angiographic scores assessing the extent and severity of the coronary lesions were obtained from a double visual analysis of each angiogram, arbitration being achieved by a quantitative measurement. Three different genotypes were analyzed: the angiotensin I-converting enzyme insertion/deletion (ACE I/D) polymorphism, the Met to Thr change at position 235 of the angiotensinogen gene (AGT M235T) and the A to C transition at position 1166 of the angiotensin II type-1 receptor gene (AT1R A1166C). No significant association was observed between these polymorphisms and the clinical characteristics of MI and non-MI subjects. While most classical risk factors were positively correlated with the angiographic scores, no significant relationship could be established with the three genotypes (r ranging from -0.08 to 0.05). Only one significant correlation was observed: between the presence of the AGT 235T allele and the extent of the coronary lesions (r = -0.19, P = 0.04) in patients with low-risk status. These overall results are not in favor of a role of these RAS genetic polymorphisms in the development of coronary atherosclerosis.