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    <title>Melkert, R.</title>
    <link>http://repub.eur.nl/res/aut/1081/</link>
    <description>List of Publications</description>
    <language>en</language>
    <image>
      <url>http://repub.eur.nl/static-eur/img/logo.png</url>
      <title>RePub, Erasmus University Rotterdam</title>
      <link>http://repub.eur.nl</link>
    </image>
    <item>
      <title>Angiographic and clinical one-year follow-up of the Cordis tantalum coil stent in a multicenter international study demonstrating improved restenosis rates when compared to pooled PTCA and BENESTENT-I data: the European Antiplatelet Stent Investigation (EASI). (Article)</title>
      <link>http://repub.eur.nl/res/pub/4841/</link>
      <pubDate>2001-01-01T00:00:00Z</pubDate>
      <description>The Cordis tantalum coil stent was assessed in a nonrandomized multicenter trial: 275 patients with stable or unstable angina were entered. Clinical follow-up was for 1 year, with repeat angiography at 6 months. The major adverse cardiac event rates (MACE) were 3%, 14%, and 17% at 1, 7, and 13 months, respectively. The procedural success rate was 96% and the subacute occlusion rate 1.5%, in a group of patients over 60% of whom had ACC/AHA type B2 or C lesions. The binary restenosis rate at 6 months was 17.3%. Minimum lumen diameter increased from 1.07 +/- 0.28 mm preprocedure to 2.93 +/- 0.34 mm poststenting and at 6 months was 1.99 +/- 0.69 mm. These results demonstrate that the Cordis tantalum stent can be used to treat complex lesions with good procedural success and low rates of subacute thrombosis and restenosis at 6 months.</description>
    </item> <item>
      <title>Total occlusion trial with angioplasty by using laser guidewire. The TOTAL trial. (Article)</title>
      <link>http://repub.eur.nl/res/pub/12887/</link>
      <pubDate>2000-01-01T00:00:00Z</pubDate>
      <description>AIMS: A randomized trial was performed to assess the safety and efficacy
      of a laser guidewire, in the treatment of chronic coronary occlusions.
      METHODS AND RESULTS: In 18 European centres, 303 patients with a chronic
      coronary occlusion were randomized to treatment with either the laser
      guidewire (n=144) or conventional guidewires (mechanical guidewire,
      n=159). The primary end-point of the study was treatment success, defined
      as reaching the true lumen distal to the occlusion by the allocated wire
      within 30 min of fluoroscopic time: laser guidewire vs mechanical
      guidewire; 52.8% (n=76) vs 47.2% (n=75), P=0.33. Serious adverse events
      following the initial guidewire attempt were 0% (laser guidewire) and 0.6%
      (mechanical guidewire), respectively. Angioplasty (performed following
      successful guidewire crossing) was successful in 179 patients (91%, laser
      guidewire n=79, mechanical guidewire n=100), followed by stent
      implantation in 149 (79%). At the 6-month angiographic follow-up, the
      difference in binary restenosis rate (laser guidewire vs mechanical
      guidewire; 45.5% vs 38.3 %, P=0.72) or reocclusion rate (25.8% vs 16.1%,
      P=0.15) did not reach statistical significance. At 1, 6 and 12 months,
      angina and event-free survival were 69%, 35% and 24% (laser guidewire) vs
      74%, 40% and 31% (mechanical guidewire). CONCLUSION: Although laser
      guidewire technology was safe, the increase in crossing success did not
      reach statistical significance.</description>
    </item> <item>
      <title>Influence of a history of smoking on short term (six month) clinical and angiographic outcome after successful coronary angioplasty (Article)</title>
      <link>http://repub.eur.nl/res/pub/8307/</link>
      <pubDate>2000-01-01T00:00:00Z</pubDate>
      <description>OBJECTIVES: To assess the influence of smoking on restenosis after
      coronary angioplasty. DESIGN AND PATIENTS: The incidence of smoking on
      restenosis was investigated in 2948 patients. They were prospectively
      enrolled in four major restenosis trials in which quantitative angiography
      was used before and immediately after successful angioplasty and again at
      six months. RESULTS: Within the study population there were 530 current
      smokers, 1690 ex-smokers, and 728 non-smokers. Smokers were more likely to
      be men (85.9% v 87. 5% v 65.3%, current v ex- v non-, p &lt; 0.001), to be
      younger (54.0 (9. 0) v 57.0 (9.1) v 59.9 (9.4) years, p &lt; 0.001), to have
      peripheral vascular disease (7.2% v 5.5% v 2.3%, p &lt; 0.001), and have
      sustained a previous myocardial infarction (42.9% v 43.9% v 37.9%, p =
      0.022), but were less likely to be diabetic (9.1% v 9.5% v 12.6%, p =
      0.043) or hypertensive (24.9% v 29.3% v 37.2, p &lt; 0.001). There was no
      significant difference in the categorical restenosis rate (&gt; 50% diameter
      stenosis) at six months (35.28% v 35.33% v 37.09%, current v ex- v non-),
      or the absolute loss (0.29 (0.54) v 0.33 (0.52) v 0. 35 (0.55) mm,
      respectively; p = 0.172). CONCLUSIONS: Although smokers have a lower
      incidence of known predisposing risk factors for atherosclerosis, they
      require coronary intervention almost six years earlier than non-smokers
      and three years earlier than ex-smokers. Once they undergo successful
      coronary angioplasty, there appears to be no evidence that smoking
      influences their short term (six month) outcome, but because of the known
      long term effects of smoking, patients should still be encouraged to
      discontinue the habit.</description>
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      <title>Carvedilol for prevention of restenosis after directional coronary atherectomy : final results of the European carvedilol atherectomy restenosis (EUROCARE) trial (Article)</title>
      <link>http://repub.eur.nl/res/pub/9300/</link>
      <pubDate>2000-01-01T00:00:00Z</pubDate>
      <description>BACKGROUND: In addition to its known properties as a competitive,
      nonselective beta and alpha-1 receptor blocker, carvedilol directly
      inhibits vascular myocyte migration and proliferation and exerts
      antioxidant effects that are considerably greater than those of vitamin E
      or probucol. This provides the basis for an evaluation of carvedilol for
      the prevention of coronary restenosis. METHODS AND RESULTS: In a
      prospective, double-blind, randomized, placebo-controlled trial, 25 mg of
      carvedilol was given twice daily, starting 24 hours before scheduled
      directional coronary atherectomy and continuing for 5 months after a
      successful procedure. The primary end point was the minimal luminal
      diameter as determined during follow-up angiography 26+/-2 weeks after the
      procedure. Of 406 randomized patients, 377 underwent attempted
      atherectomy, and in 324 (88.9%), a &lt;/=50% diameter stenosis was achieved
      without the use of a stent. Evaluable follow-up angiography was available
      in 292 eligible patients (90%). No differences in minimal luminal diameter
      (1.99+/-0.73 mm versus 2.00+/-0.74 mm), angiographic restenosis rate
      (23.4% versus 23.9%), target lesion revascularization (16.2 versus 14.5),
      or event-free survival (79.2% versus 79.7%) between the placebo and
      carvedilol groups were observed at 7 months. CONCLUSIONS: The maximum
      recommended daily dose of the antioxidant and beta-blocker carvedilol
      failed to reduce restenosis after successful atherectomy. These findings
      are in contrast to those of the Multivitamins and Probucol Trial, which
      raises doubts regarding the validity of the interpretation that restenosis
      reduction by probucol was via antioxidant effects. The relationship
      between antioxidant agents and restenosis remains to be elucidated.</description>
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      <title>Anticoagulant properties, clinical efficacy and safety of efegatran, a direct thrombin inhibitor, in patients with unstable angina. (Article)</title>
      <link>http://repub.eur.nl/res/pub/12808/</link>
      <pubDate>1999-08-01T00:00:00Z</pubDate>
      <description>AIMS: Thrombin plays a key role in the clinical syndrome of unstable
      angina. We investigated the safety and efficacy of five dose levels of
      efegatran sulphate, a direct thrombin inhibitor, compared to heparin in
      patients with unstable angina. METHODS: Four hundred and thirty-two
      patients with unstable angina were enrolled. Five dose levels of efegatran
      were studied sequentially, ranging from 0.105 mg. kg(-1). h(-1)to 1.2 mg.
      kg(-1). h(-1)over 48 h. Safety was assessed clinically, with reference to
      bleeding and by measuring clinical laboratory parameters. Efficacy was
      assessed by the number of patients experiencing any episode of recurrent
      ischaemia as measured by computer-assisted continuous ECG ischaemia
      monitoring. Clinical end-points were: episodes of recurrent angina,
      myocardial infarction, coronary intervention (PTCA or CABG), and death.
      RESULTS: Efegatran demonstrated dose dependent ex-vivo anticoagulant
      activity with the highest dose level of 1.2 mg. kg(-1). h(-1)resulting in
      steady state mean activated partial thromboplastin time values of
      approximately three times baseline. Thrombin time was also increased.
      Neither of the efegatran doses studied were able to suppress myocardial
      ischaemia during continuous ECG ischaemia monitoring to a greater extent
      than that seen with heparin. There were no statistically significant
      differences in clinical outcome or major bleeding between the efegatran
      and heparin groups. Minor bleeding and thrombophlebitis occurred more
      frequently in the efegatran treated patients. CONCLUSION: Administration
      of efegatran sulphate at levels of at least 0.63 mg. kg(-1). h(-1)provided
      an anti-thrombotic effect which is at least comparable to an activated
      partial thromboplastin time adjusted heparin infusion. There was no excess
      of major bleeding. The level of thrombin inhibition by efegatran, as
      measured by activated partial thromboplastin time, appeared to be more
      stable than with heparin. Thus, like other thrombin inhibitors, efegatran
      sulphate is easier to administer than heparin. However, no clinical
      benefits of efegatran over heparin were apparent.</description>
    </item> <item>
      <title>Does angiography six months after coronary intervention influence management and outcome? Benestent II Investigators. (Article)</title>
      <link>http://repub.eur.nl/res/pub/4911/</link>
      <pubDate>1999-01-01T00:00:00Z</pubDate>
      <description>OBJECTIVES This study was performed to assess whether angiography six months after coronary balloon angioplasty or stent implantation has an influence on clinical management and one-year outcome.
BACKGROUND The Benestent II study randomized 827 patients to balloon angioplasty or stent implantation. A subrandomization was undertaken allocating patients to six-month clinical  follow-up (CF) or clinical and angiographic follow-up (AF).
METHODS Seven hundred and six patients (349 CF and 357 AF) had no intercurrent angiography, so that restenosis and disease progression elsewhere remained unknown until the time of
six-month follow-up. These two groups, which were well matched at enrolment, were compared with respect to symptoms, medication and major cardiac events defined as death,
myocardial infarction and need for revascularization at six and 12 months.
RESULTS At six-month follow-up, 53 (15%) of the CF and 76 (21%) of the AF patients had stable angina (p 5 0.041), while 5 (1%) and 4 (1%) had symptoms of unstable angina. At 12-month
follow-up, 44 (13%) patients in both groups had stable angina, and only 1 patient in the CF group had unstable angina. Seventy-seven patients (27 CF and 50 AF; p , 0.01) had major
cardiac events between 6 and 12 months. Of the 349 patients in the CF group, 21 underwent repeat percutaneous transluminal coronary angioplasty or coronary artery bypass graft surgery
between 6 and 12 months, compared with 44 of the 357 patients in the AF group (relative risk 2.05 [1.24 to 3.37], p 5 0.003).
CONCLUSIONS Patients who had AF six months after balloon angioplasty or stent implantation experienced more repeat revascularization procedures than those who had CF. They also had significantly more angina at six-month follow-up but this may be due to bias</description>
    </item> <item>
      <title>A randomized placebo-controlled trial of fluvastatin for prevention of restenosis after successful coronary balloon angioplasty; final results of the fluvastatin angiographic restenosis (FLARE) trial (Article)</title>
      <link>http://repub.eur.nl/res/pub/9059/</link>
      <pubDate>1999-01-01T00:00:00Z</pubDate>
      <description>BACKGROUND: The 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase
      inhibitors competitively inhibit biosynthesis of mevalonate, a precursor
      of non-sterol compounds involved in cell proliferation. Experimental
      evidence suggests that fluvastatin may, independent of any lipid lowering
      action, exert a greater direct inhibitory effect on proliferating vascular
      myocytes than other statins. The FLARE (Fluvastatin Angioplasty
      Restenosis) Trial was conceived to evaluate the ability of fluvastatin 40
      mg twice daily to reduce restenosis after successful coronary balloon
      angioplasty (PTCA). METHODS: Patients were randomized to either placebo or
      fluvastatin 40 mg twice daily beginning 2-4 weeks prior to planned PTCA
      and continuing after a successful PTCA (without the use of a stent), to
      follow-up angiography at 26+/-2 weeks. Clinical follow-up was completed at
      40 weeks. The primary end-point was angiographic restenosis, measured by
      quantitative coronary angiography at a core laboratory, as the loss in
      minimal luminal diameter during follow-up. Clinical end-points were death,
      myocardial infarction, coronary artery bypass graft surgery or
      re-intervention, up to 40 weeks after PTCA. RESULTS: Of 1054 patients
      randomized, 526 were allocated to fluvastatin and 528 to placebo. Among
      these, 409 in the fluvastatin group and 427 in the placebo group were
      included in the intention-to-treat analysis, having undergone a successful
      PTCA after a minimum of 2 weeks of pre-treatment. At the time of PTCA,
      fluvastatin had reduced LDL cholesterol by 37% and this was maintained at
      33% at 26 weeks. There was no difference in the primary end-point between
      the treatment groups (fluvastatin 0.23+/-0.49 mm vs placebo 0.23+/-0.52
      mm, P=0.95) or in the angiographic restenosis rate (fluvastatin 28%,
      placebo 31%, chi-square P=0.42), or in the incidence of the composite
      clinical end-point at 40 weeks (22.4% vs 23.3%; logrank P=0.74). However,
      a significantly lower incidence of total death and myocardial infarction
      was observed in six patients (1.4%) in the fluvastatin group and 17 (4.0%)
      in the placebo group (log rank P=0.025). CONCLUSION: Treatment with
      fluvastatin 80 mg daily did not affect the process of restenosis and is
      therefore not indicated for this purpose. However, the observed reduction
      in mortality and myocardial infarction 40 weeks after PTCA in the
      fluvastatin treated group has not been previously reported with statin
      therapy. Accordingly, a priori investigation of this finding is indicated
      and a new clinical trial with this intention is already underway.</description>
    </item> <item>
      <title>Reduction of Recurrent Ischemia With Abciximab During Continuous ECG Ischemia Monitoring in Patients With Unstable Angina Refractory to Standard Treatment (CAPTURE) (Article)</title>
      <link>http://repub.eur.nl/res/pub/5582/</link>
      <pubDate>1998-01-01T00:00:00Z</pubDate>
      <description>Background—In the CAPTURE (c7E3 Fab Anti Platelet Therapy in Unstable REfractory angina) trial, 1265 patients with refractory unstable angina were treated with abciximab or placebo, in addition to standard treatment from 16 to 24 hours preceding coronary intervention through 1 hour after intervention. To investigate the incidence of recurrent ischemia and the ischemic burden, a subset of 332 patients (26%) underwent continuous vector-derived 12-lead ECG-ischemia monitoring.

Methods and Results—Patients were monitored from start of treatment through 6 hours after coronary intervention. Ischemic episodes were detected in 31 (18%) of the 169 abciximab and in 37 (23%) of the 163 placebo patients (NS). Only 9 (5%) of abciximab versus 22 (14%) of placebo patients had 2 ST episodes (P&lt;0.01). In patients with ischemia, abciximab significantly reduced total ischemic burden (P&lt;0.02), which was calculated alternatively as the total duration of ST episodes per patient, the area under the curve of the ST vector magnitude during episodes, or the sum of the areas under the curves of 12 leads during episodes. Twenty-one patients (6%) suffered a myocardial infarction (MI) (18) or died (3) within 5 days of treatment. The presence of asymptomatic and symptomatic ST episodes during the monitoring period preceding coronary intervention was associated with an increased relative risk of these events of 3.2 (95% CI 1.4, 7.4) and 4.1 (95% CI 1.4, 12.2), respectively.

Conclusions—Recurrent ischemia predicts MI or death within 5 days of follow-up. Treatment with abciximab is associated with a reduction of frequent ischemia and a reduction of total ischemic burden in patients with refractory unstable angina. As such, patients with ischemia derive particularly high benefit from abciximab.</description>
    </item> <item>
      <title>Reduction of recurrent ischemia with abciximab during continuous ECG-ischemia monitoring in patients with unstable angina refractory to standard treatment (CAPTURE) (Article)</title>
      <link>http://repub.eur.nl/res/pub/8907/</link>
      <pubDate>1998-01-01T00:00:00Z</pubDate>
      <description>BACKGROUND: In the CAPTURE (c7E3 Fab Anti Platelet Therapy in Unstable
      REfractory angina) trial, 1265 patients with refractory unstable angina
      were treated with abciximab or placebo, in addition to standard treatment
      from 16 to 24 hours preceding coronary intervention through 1 hour after
      intervention. To investigate the incidence of recurrent ischemia and the
      ischemic burden, a subset of 332 patients (26%) underwent continuous
      vector-derived 12-lead ECG-ischemia monitoring. METHODS and RESULTS:
      Patients were monitored from start of treatment through 6 hours after
      coronary intervention. Ischemic episodes were detected in 31 (18%) of the
      169 abciximab and in 37 (23%) of the 163 placebo patients (NS). Only 9
      (5%) of abciximab versus 22 (14%) of placebo patients had &gt;/=2 ST episodes
      (P&lt;0.01). In patients with ischemia, abciximab significantly reduced total
      ischemic burden (P&lt;0.02), which was calculated alternatively as the total
      duration of ST episodes per patient, the area under the curve of the ST
      vector magnitude during episodes, or the sum of the areas under the curves
      of 12 leads during episodes. Twenty-one patients (6%) suffered a
      myocardial infarction (MI) (18) or died (3) within 5 days of treatment.
      The presence of asymptomatic and symptomatic ST episodes during the
      monitoring period preceding coronary intervention was associated with an
      increased relative risk of these events of 3.2 (95% CI 1.4, 7.4) and 4.1
      (95% CI 1.4, 12.2), respectively. CONCLUSIONS: Recurrent ischemia predicts
      MI or death within 5 days of follow-up. Treatment with abciximab is
      associated with a reduction of frequent ischemia and a reduction of total
      ischemic burden in patients with refractory unstable angina. As such,
      patients with ischemia derive particularly high benefit from abciximab.</description>
    </item> <item>
      <title>Contributions of frequency distribution analysis to the understanding of coronary restenosis. A reappraisal of the gaussian curve. (Article)</title>
      <link>http://repub.eur.nl/res/pub/5038/</link>
      <pubDate>1996-01-01T00:00:00Z</pubDate>
      <description>Background Clinical restenosis after balloon angioplasty can be categorized by use of dichotomous terms based on the presence or absence of recurrent myocardial ischemia. In contrast, recent investigations have concluded that late luminal renarrowing, documented through angiographic imaging, occurs to a variable extent in nearly all stenoses. This process has been characterized by a gaussian or normal frequency distribution, with restenosis simply representing an extreme form of this delayed remodeling. In the current study, frequency distribution analysis was used to examine the process of coronary restenosis in a large cohort of patients at risk.

Methods and Results Quantitative coronary angiographic analysis was applied to 9279 cineangiograms obtained in 3093 patients before and immediately after angioplasty and after 6-month follow-up. Late loss, defined as the change in minimum lumen diameter of the target stenosis from postdilation to follow-up, did not statistically conform to a normal distribution (P&lt;.0001 by both 2 statistic and Kolmogorov-Smirnov test), even after the exclusion of the 236 stenoses that displayed total occlusions at follow-up angiography. Examination of deviations from a normal curve revealed an excessively high frequency of stenoses that experienced either little change (0.0±0.3 mm) or marked change (1.0 to 2.0 mm) in late loss, with a low frequency of stenoses with intermediate values (0.3 to 1.0 mm). Similarly, although the distribution of percent diameter stenosis of the target lesion was statistically normal immediately after dilation, this gaussian distribution disappeared during the follow-up period. Other angiographic indexes of restenosis also failed to approximate a normal curve. In an attempt to improve the goodness of fit, a probabilistic model of late loss was created on the basis of deconvolution of the observed data distribution. Two theoretical, discrete populations of stenoses were identified, one with and one without overall late luminal narrowing. Unlike the gaussian distribution, this model provided a good representation of the observed data (P=NS for lack of fit).

Conclusions The frequency distributions of angiographic indexes of restenosis often superficially resemble a gaussian curve, an appearance that is artifactually enhanced by the measurement imprecision of current quantitative techniques. Nevertheless, standard indexes of coronary restenosis fail to conform statistically to a normal distribution. The pattern of deviations observed supports the possible existence of discrete subpopulations of lesions, each with a different propensity toward the development of restenosis after coronary intervention.</description>
    </item> <item>
      <title>Role of Angiographically Identifiable Thrombus on Long-term Luminal Renarrowing After Coronary Angioplasty: a quantitative angiographic analysis. (Article)</title>
      <link>http://repub.eur.nl/res/pub/5042/</link>
      <pubDate>1996-01-01T00:00:00Z</pubDate>
      <description>Background Experimental studies suggest that mural thrombus may be involved in postangioplasty restenosis. The aim of our study was to examine the role of angiographically identifiable thrombus in the clinical situation.

Methods and Results The study population comprised 2950 patients (3583 lesions). The presence of angiographically identifiable thrombus either before or after the procedure was defined as the presence of a generalized haziness or filling defect within the arterial lumen. Restenosis was assessed by both a categorical (&gt;50% diameter stenosis at follow-up) and a continuous approach (absolute and relative losses). The study population included 160 lesions with and 3423 lesions without angiographically identifiable thrombus. The categorical restenosis rate was significantly higher in lesions containing angiographically identifiable thrombus: 43.1% versus 34.4%, P&lt;.01; relative risk, 1.449; CI, 1.051 to 1.997. The absolute and relative losses were also higher in lesions containing angiographically identifiable thrombus (absolute loss, 0.43±0.66 versus 0.32±0.52; relative loss, 0.16±0.26 versus 0.13±0.21; both P&lt;.05). The higher restenosis in these lesions was due primarily to an increased incidence of occlusion at follow-up angiography in this group: 13.8% versus 5.7%, P&lt;.001. When lesions that went on to occlude by the time of follow-up angiography were excluded from the analysis, the restenosis rate between the two groups was similar by both the categorical (34.1% versus 30.4%, P=NS; relative risk, 1.183; CI, 0.824 to 1.696) and continuous (absolute loss, 0.23±0.46 versus 0.24±0.42, P=NS; relative loss, 0.09±0.17 versus 0.09±0.16, P=NS) approaches.

Conclusions Our results indicate that the presence of angiographically identifiable thrombus at the time of the angioplasty procedure is associated with higher restenosis. The mechanism by which this occurs is through vessel occlusion at follow-up angiography. Measures aimed at improving outcome in this group of patients should be focused in this direction.</description>
    </item> <item>
      <title>Differences in restenosis propensity of devices for transluminal coronary intervention. A quantitative angiographic comparison of balloon angioplasty, directional atherectomy, stent implantation and excimer laser angioplasty. CARPORT, MERCATOR, MARCATOR, PARK, and BENESTENT Trial Groups. (Article)</title>
      <link>http://repub.eur.nl/res/pub/5068/</link>
      <pubDate>1995-01-01T00:00:00Z</pubDate>
      <description>With the increasing clinical application of new devices for percutaneous coronary revascularization, maximization of the acute angiographic result has become widely recognized as a key factor in maintained clinical and angiographic success. What is unclear, however, is whether the specific mode of action of different devices might exert an additional independent effect on late luminal renarrowing. The purpose of this study was to investigate such a difference in the degree of provocation of luminal renarrowing (or 'restenosis propensity') by different devices, among 3660 patients, who had 4342 lesions successfully treated by balloon angioplasty (n = 3797), directional coronary atherectomy (n = 200), Palmaz-Schatz stent implantation (n = 229) or excimer laser coronary angioplasty (n = 116) and who also underwent quantitative angiographic analysis pre- and post-intervention and at 6-month follow-up. To allow valid comparisons between the groups, because of significant differences in coronary vessel size (balloon angioplasty = 2.62 +/- 0.55 mm, directional coronary atherectomy = 3.28 +/- 0.62 mm, excimer laser coronary angioplasty = 2.51 +/- 0.47 mm, Palmaz-Schatz = 3.01 +/- 0.44 mm; P &lt; 0.0001), the comparative measurements of interest selected were the 'relative loss' in luminal diameter (RLoss = loss/vessel size) to denote the restenosis process, and the 'relative lumen at follow-up' (RLfup = minimal luminal diameter at follow up/vessel size) to represent the angiographic outcome. For consistency, lesion severity pre-intervention was represented by the 'relative lumen pre' (RLpre = minimal luminal diameter pre/vessel size) and the luminal increase at intervention was measured as 'relative gain' (relative gain = gain/ vessel size). Differences in restenosis propensity between devices was evaluated by univariate and multivariate analysis. Multivariate models were constructed to determine relative loss and relative lumen at follow-up, taking account of relative lumen pre-intervention, lesion location, relative gain, vessel size and the device used. In addition, model-estimated relative loss and relative lumen at follow-up at given relative lumen pre-intervention relative gain and vessel size, were compared among the four groups. Significant differences were detected among the groups both with respect to these estimates, as well as in the degree of influence of progressively increasing relative gain, on the extent of renarrowing (relative loss) and angiographic outcome (relative lumen at follow-up), particularly at higher levels of luminal increase (relative gain). Specifically, lesions treated by balloon angioplasty or Palmaz-Schatz stent implantation (the predominantly 'dilating' interventions) were associated with more favourable angiographic profiles than directional atherectomy or excimer laser (the mainly 'debulking' interventions). Significant effects of lesion severity and location, as well as the well known influence of luminal increase on both luminal renarrowing and late angiographic outcome were also noted. These findings indicate that propensity to restenosis after apparently successful intervention is influenced not only by the degree of luminal enlargement achieved at intervention, but by the device used to achieve it. In view of the clinical implications of such findings, further evaluation in larger randomized patient populations is warranted.</description>
    </item> <item>
      <title>Long-term Luminal Renarrowing After Successful Elective Coronary Angioplasty of Total Occlusions (Article)</title>
      <link>http://repub.eur.nl/res/pub/5083/</link>
      <pubDate>1995-01-01T00:00:00Z</pubDate>
      <description>Background The long-term angiographic outcome after successful dilatation of coronary occlusions remains unclear. The objective of this study was to examine long-term restenosis after successful balloon dilatation of coronary occlusions at a predetermined time interval with quantitative angiography and compare this with a control population of stenoses.

Methods and Results The study population comprised 2950 patients (3583 lesions) prospectively enrolled in and successfully completing four major restenosis trials (86% quantitative angiographic follow-up). Cineangiographic films were processed and analyzed at a central core laboratory with the use of an automated interpolated edge detection technique. The study population comprised 266 occlusions (7%) defined as total when there was absent anterograde filling beyond the lesion (109 lesions) and functional (157 lesions) when faint, late anterograde opacification of the distal segment was seen in the absence of a discernible luminal continuity; 3317 lesions were defined as stenoses (93%). Restenosis was significantly higher after successful dilatation of occlusions than of stenoses. With the categorical (&gt;50% diameter stenosis at follow-up) approach, the restenosis rate was 44.7% in occlusions compared with 34.0% in stenoses (P&lt;.001; relative risk, 1.575; CI, 1.224 to 2.027). Similarly, the absolute loss (defined as the change in minimal lumen diameter between post coronary angioplasty and follow-up; in millimeters, mean±SD) (0.43±0.68) in occlusions was significantly higher than in stenoses (0.31±0.51, P&lt;.001), as was the relative loss, defined as the change in minimal lumen diameter between postangioplasty and follow-up, adjusted for the vessel size (0.17±0.28 versus 0.12±0.20, P&lt;.001). The higher restenosis rate in the occlusions group was due predominantly to an increased number of occlusions at follow-up angiography in this group (19.2% compared with 5.0% for stenoses, P&lt;.001). Within the occlusions group, there were no significant differences in long-term outcome between total and functional occlusions (restenosis rate, 45.0% versus 44.6%; reocclusion rate, 23.9% versus 15.9%; absolute loss, 0.53±0.69 versus 0.36±0.67; relative loss, 0.21±0.28 versus 0.15±0.28; P=NS).

Conclusions These results indicate that successfully dilated coronary occlusions, both total and functional, have a higher rate of angiographic restenosis at 6 months than stenoses. This is due chiefly to a higher rate of occlusion at follow-up angiography in this group of lesions. Measures aimed at reducing restenosis after successful dilatation of coronary occlusion should be focused in this direction.</description>
    </item> <item>
      <title>Quantitative angiographic comparison of elastic recoil after coronary excimer laser-assisted balloon angioplasty and balloon angioplasty alone. (Article)</title>
      <link>http://repub.eur.nl/res/pub/5087/</link>
      <pubDate>1995-01-01T00:00:00Z</pubDate>
      <description></description>
    </item> <item>
      <title>Irish Cardiac Society - Proceedings of the Annual General Meeting held November 1993 (Article)</title>
      <link>http://repub.eur.nl/res/pub/14919/</link>
      <pubDate>1994-08-01T00:00:00Z</pubDate>
      <description></description>
    </item> <item>
      <title>Optimal use of directional coronary atherectomy is required to ensure long-term angiographic benefit: a study with matched procedural outcome after atherectomy and angioplasty (Article)</title>
      <link>http://repub.eur.nl/res/pub/4619/</link>
      <pubDate>1994-01-01T00:00:00Z</pubDate>
      <description>OBJECTIVES. This study was designed to examine whether restenosis is related to the extent or mechanism of lumen improvement and to explore angiographic determinants of optimal atherectomy. BACKGROUND. Directional atherectomy induces a greater extent of immediate gain and late loss but has not been found to yield a better late angiographic lumen than angioplasty in randomized trials. The difference in lumen renarrowing may be related to either the extent or the mechanism of immediate gain. The design of previous studies has precluded the detection of a device-specific effect on restenosis. METHODS. A retrospective analysis was based on matching a prospectively collected series of 80 native coronary arteries successfully treated with atherectomy with a prospectively collected series of 80 native coronary arteries successfully treated with balloon angioplasty. Angiographic analysis was performed in 160 lesions to explore whether a specific device-related effect exists. Multivariate analyses were performed to determine the correlates of minimal lumen diameter at follow-up and late lumen loss and to identify the procedural characteristics for optimal atherectomy. RESULTS. Matching resulted in two comparable groups with equivalent baseline clinical and stenosis characteristics. By study design, atherectomy and angioplasty resulted in similar mean (+/- SD) immediate lumen gain (1.15 +/- 0.44 vs. 1.10 +/- 0.40 mm, p = 0.50). However, lumen loss was more pronounced after atherectomy, and, thus, the minimal lumen diameter at follow-up differed significantly between the two groups (1.78 +/- 0.57 vs. 2.00 +/- 0.56 mm, p = 0.001). Device type was retained in the multivariate analysis as an independent predictor of late minimal lumen diameter and lumen loss. Multivariate analysis identified vessel size and immediate gain as determinants of optimal atherectomy. CONCLUSIONS. Restenosis is a consequence not only of the extent of lumen improvement but also of the mechanism of vessel wall injury (debulking vs. dilating). While performing atherectomy, the operator should strive for an optimal procedural result to accommodate an increased intimal hyperplastic response.</description>
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      <title>Evaluation of Ketanserin in the Prevention of Restenosis After Percutaneous Transluminal Coronary Angioplasty (Article)</title>
      <link>http://repub.eur.nl/res/pub/4548/</link>
      <pubDate>1993-01-01T00:00:00Z</pubDate>
      <description>BACKGROUND. Ketanserin is a serotonin S2-receptor antagonist that inhibits the platelet activation and vasoconstriction induced by serotonin and also inhibits the mitogenic effect of serotonin on vascular smooth muscle cells. METHODS AND RESULTS. We conducted a randomized, double blind, placebo-controlled trial to assess the effect of ketanserin in restenosis prevention after percutaneous transluminal coronary angioplasty (PTCA). Patients received either ketanserin (loading dose, 40 mg 1 hour before PTCA; maintenance dose, 40 mg bid for 6 months) or matched placebo. In addition, all patients received aspirin for 6 months. Coronary angiograms before PTCA, after PTCA, and at 6 months were quantitatively analyzed. Six hundred fifty-eight patients were entered into the intention-to-treat analysis. The primary clinical end point of the study was the occurrence between PTCA and 6 months of any one of the following: cardiac death, myocardial infarction, the need for repeat angioplasty, or bypass surgery. It also included the need for revascularization actuated by findings at 6-month follow-up angiography. The primary clinical end point was reached by 92 (28%) patients in the ketanserin group and 104 (32%) in the placebo group (RR, 0.89; 95% CI, 0.70, 1.13; P = .38). Quantitative angiography after PTCA and at follow-up was available in 592 patients (ketanserin, 287; control, 305). The mean difference in minimal lumen diameter between post-PTCA and follow-up angiogram (primary angiographic end point) was 0.27 +/- 0.49 mm in the ketanserin group and 0.24 +/- 0.52 mm in the control group (difference, 0.03 mm; 95% CI, -0.05, 0.11; P = .50). CONCLUSIONS. Ketanserin at the dose administered in this trial failed to reduce the loss in minimal lumen diameter during follow-up after PTCA and did not significantly improve the clinical outcome.</description>
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