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Pim de Feyter

Publications and source records attributed to Pim de Feyter.

45 records · Page 3Linked to original sources

Sirolimus-eluting stent for treatment of complex in-stent restenosis: the first clinical experience.

OBJECTIVES: In this study, we assess the value of sirolimus eluting stent (SES) implantation in patients with complex in-stent restenosis (ISR). BACKGROUND: The treatment of ISR remains a therapeutic challenge, since many pharmacological and mechanical approaches have shown disappointing results. The SESs have been reported to be effective in de-novo coronary lesions. METHODS: Sixteen patients with severe, recurrent ISR in a native coronary artery (average lesion length 18.4 mm) and objective evidence of ischemia were included. They received one or more 18 mm Bx VELOCITY SESs (Cordis Waterloo, Belgium). Quantitative angiographic and three-dimensional intravascular ultrasound (IVUS) follow-up was performed at four months, and clinical follow-up at nine months. RESULTS: The SES implantation (n = 26) was successful in all 16 patients. Four patients had recurrent restenosis following brachytherapy, and three patients had totally occluded vessels preprocedure. At four months follow-up, one patient had died and three patients had angiographic evidence of restenosis (one in-stent and two in-lesion). In-stent late lumen loss averaged 0.21 mm and the volume obstruction of the stent by IVUS was 1.1%. At nine months clinical follow-up, three patients had experienced four major adverse cardiac events (two deaths and one acute myocardial infarction necessitating repeat target vessel angioplasty). CONCLUSIONS: The SES implantation in patients with severe ISR lesions effectively prevents neointima formation and recurrent restenosis at four months angiographic follow-up.

Adult↗

Noninvasive angiographic evaluation of coronary stents with multi-slice spiral computed tomography.

BACKGROUND: The number of patients with obstructive coronary artery disease, who undergo coronary angioplasty with implantation of stents, is ever increasing. As an alternative to catheter-based angiography, ECG-gated multi-slice spiral computed tomography (MSCT) allows noninvasive imaging of the coronary arteries. However, coronary stents have been notoriously difficult to assess by CT. METHODS AND RESULTS: In vitro experiments were performed, using varying detector collimations, contrast concentrations, stent positions and stent diameters, to evaluate the feasibility and image characteristics of stents. The stent-related high-density artifacts expand the apparent size of the stent struts. This blooming effect is a fairly constant phenomenon, and therefore relatively less evident in larger-diameter stents. The in vivo images show the same artifacts, but assessment is further complicated by motion, lower contrast-to-noise, and vessel wall calcifications. CONCLUSIONS: The clinical value of CT after percutaneous coronary intervention currently remains largely limited to the detection of stent occlusion, and the progression of coronary artery disease in the remaining nonstented segments. Subtle in-stent abnormalities cannot be reliably imaged. Some relief will be offered by improvements in scanner technology, but the use of less radiopaque stent material would be more effective.

Angioplasty, Balloon, Coronary↗

Intravascular palpography for high-risk vulnerable plaque assessment.

BACKGROUND: The composition of an atherosclerotic plaque is considered more important than the degree of stenosis. An unstable lesion may rupture and cause an acute thrombotic reaction. Most of these lesions contain a large lipid pool covered by an inflamed thin fibrous cap. The stress in the cap increases with decreasing cap thickness and increasing macrophage infiltration. Intravascular ultrasound (IVUS) palpography might be an ideal technique to assess the mechanical properties of high-risk plaques. TECHNIQUE: Palpography assesses the local mechanical properties of tissue using its deformation caused by the intraluminal pressure. IN VITRO VALIDATION: The technique was validated in vitro using diseased human coronary and femoral arteries. Especially between fibrous and fatty tissue, a highly significant difference in strain (p = 0.0012) was found. Additionally, the predictive value to identify the vulnerable plaque was investigated. A high-strain region at the lumen-vessel wall boundary has an 88% sensitivity and 89% specificity for identifying such plaques. IN VIVO VALIDATION: In vivo, the technique was validated in an atherosclerotic Yucatan minipig animal model. This study also revealed higher strain values in fatty than fibrous plaques (p < 0.001). The presence of a high-strain region at the lumenplaque interface has a high predictive value to identify macrophages. PATIENT STUDIES: Patient studies revealed high-strain values (1-2%) in thin-cap fibrous atheroma. Calcified material showed low strain values (0-0.2%). With the development of three-dimensional (3-D) palpography, identification of highstrain spots over the full length of a coronary artery becomes available. CONCLUSION: Intravascular palpography is a unique tool to assess lesion composition and vulnerability. The development of 3-D palpography provides a technique that may develop into a clinical tool to identify the high-risk plaque.

Animals↗

MS-CT coronary imaging.

Magnetic resonance imaging and computed tomography (CT) have recently emerged as two techniques that can noninvasively visualize the coronary arteries. The latest generation 16-row detector multislice CT scanner is now considered the most reliable technique to visualize the coronaries. The sensitivity and specificity to detect a significant (>50% diameter stenosis) coronary stenosis is +/-94% and +/-90%, respectively. Further technical improvements are necessary to make CT a clinically reliable diagnostic tool.

Cardiomyopathies↗

Persistent inhibition of neointimal hyperplasia after sirolimus-eluting stent implantation: long-term (up to 2 years) clinical, angiographic, and intravascular ultrasound follow-up.

BACKGROUND: Early results of sirolimus-eluting stent implantation showed a nearly complete abolition of neointimal hyperplasia. The question remains, however, whether the early promising results will still be evident at long-term follow-up. The objective of our study was to evaluate the efficiency of sirolimus-eluting stent implantation for up to 2 years of follow-up. METHODS AND RESULTS: Fifteen patients with de novo coronary artery disease were treated with 18-mm sirolimus-eluting Bx-Velocity stents (Cordis) loaded with 140 microg sirolimus/cm2 metal surface area in a slow release formulation. Quantitative angiography (QCA) and intravascular ultrasound (IVUS) were performed according to standard protocol. Sirolimus-eluting stent implantation was successful in all 15 patients. During the in-hospital course, 1 patient died of cerebral hemorrhage after periprocedural administration of abciximab, and 1 patient underwent repeat stenting after 2 hours because of edge dissection that led to acute occlusion. Through 6 months and up to 2 years of follow-up, no additional events occurred. QCA analysis revealed no significant change in stent minimal lumen diameter or percent diameter stenosis, and 3-dimensional IVUS showed no significant deterioration in lumen volume. In 2 patients, additional stenting was performed because of significant lesion progression remote from the sirolimus-eluting stent. CONCLUSION: Sirolimus-eluting stents showed persistent inhibition of neointimal hyperplasia for up to 2 years of follow-up.

Abciximab↗

Fluvastatin for prevention of cardiac events following successful first percutaneous coronary intervention: a randomized controlled trial.

CONTEXT: Percutaneous coronary intervention (PCI) is associated with excellent short-term improvements in ischemic symptoms, yet only three fifths of PCI patients at 5 years and one third of patients at 10 years remain free of major adverse cardiac events (MACE). OBJECTIVE: To determine whether treatment with fluvastatin reduces MACE in patients who have undergone PCI. DESIGN AND SETTING: Randomized, double-blind, placebo-controlled trial conducted at 77 referral centers in Europe, Canada, and Brazil. PATIENTS: A total of 1677 patients (aged 18-80 years) recruited between April 1996 and October 1998 with stable or unstable angina or silent ischemia following successful completion of their first PCI who had baseline total cholesterol levels between 135 and 270 mg/dL (3.5-7.0 mmol/L), with fasting triglyceride levels of less than 400 mg/dL (4.5 mmol/L). INTERVENTIONS: Patients were randomly assigned to receive treatment with fluvastatin, 80 mg/d (n = 844), or matching placebo (n = 833) at hospital discharge for 3 to 4 years. MAIN OUTCOME MEASURE: Survival time free of MACE, defined as cardiac death, nonfatal myocardial infarction, or reintervention procedure, compared between the treatment and placebo groups. RESULTS: Median time between PCI and first dose of study medication was 2.0 days, and median follow-up was 3.9 years. MACE-free survival time was significantly longer in the fluvastatin group (P =.01). One hundred eighty-one (21.4%) of 844 patients in the fluvastatin group and 222 (26.7%) of 833 patients in the placebo group had at least 1 MACE (relative risk [RR], 0.78; 95% confidence interval [CI], 0.64-0.95; P =.01). This result was independent of baseline total cholesterol levels (above [RR, 0.76; 95% CI, 0.56-1.04] vs below [RR, 0.77; 95% CI, 0.57-1.02] the median). In subgroup analysis, the risk of MACE was reduced in patients with diabetes (n = 202; RR, 0.53; 95% CI, 0.29-0.97; P =.04) and in those with multivessel disease (n = 614; RR, 0.66; 95% CI, 0.48-0.91; P =.01) who received fluvastatin compared with those who received placebo. There were no instances of creatine phosphokinase elevations 10 or more times the upper limit of normal or rhabdomyolysis in the fluvastatin group. CONCLUSION: Fluvastatin treatment in patients with average cholesterol levels undergoing their first successful PCI significantly reduces the risk of major adverse cardiac events.

Adult↗

Three-dimensional coronary anatomy in contrast-enhanced multislice computed tomography.

A number of three-dimensional imaging modalities, such as magnetic resonance imaging, electron beam computed tomography, ultrasonography, and multislice computed tomography have been introduced in cardiovascular medicine. One of the most recently developed techniques, multislice computed tomographic coronary angiography, allows assessment of the small coronary vessels. The entire heart is scanned within a single breathhold and contrast-enhanced images are reconstructed through retrospective electrocardiographic gating. Instead of the conventional two-dimensional projection images, multislice computed tomographic data can be displayed in a three-dimensional, volume-rendered manner. This paper presents an overview of the cardiac and coronary morphology as it is imaged with contrast-enhanced multislice computed tomography. Further imaging characteristics of computed tomographic angiography are discussed.

Contrast Media↗

Noninvasive visualisation of coronary atherosclerosis with multislice computed tomography.

Computed Tomography (Electron Beam Tomography: EBCT and multislice computed tomography: MSCT) have recently emerged as non-invasive diagnostic modalities that can quantify coronary calcium which is not only as indicator of coronary risk, but also permits assessment of the coronary lumen. The 16-slice MS-CT, the most recent CT-scanner has a very high resolution, which allows non-invasive assessment of coronary plaques. This has led to a stimulus for further research to assess the role of MSCT coronary plaque imaging in the identification of high-risk coronary plaques.

Age Distribution↗