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Felix Zijlstra

Publications and source records attributed to Felix Zijlstra.

At least 73 records · Page 4Linked to original sources
PubMed2004

Assessing the prognostic value of coronary endothelial function in patients referred for a first coronary angiogram.

At present, the value of endothelial function as a prognostic tool has been evaluated only in selected groups of patients with mild or minor coronary artery disease, not in the complete spectrum of patients presenting with angina. The objective of this study was to evaluate whether endothelium-dependent vasodilation of the coronary arteries in response to acetylcholine infusion as a marker of endothelial function would have prognostic value in patients referred for a first coronary angiogram. The data suggest that endothelial function assessment does not contribute to the prediction of outcomes in patients referred for a first coronary angiogram.

Adolescent↗
PubMed2004

Detection, visualization and evaluation of anomalous coronary anatomy on 16-slice multidetector-row CT.

Early identification and evaluation of relatively frequent anomalous coronary anatomy is quite relevant because of the occurrence of sudden cardiac death or related symptoms of myocardial ischemia. Selective coronary angiography (CAG) is invasive, expensive and cannot always provide the required information adequately. Recently, non-invasive imaging techniques such as magnetic resonance imaging and multidetector-row computed tomography (MDCT) have been shown to provide a good anatomical view of the coronary artery tree. This study aims to demonstrate the value of 16-MDCT for evaluation of anomalous coronary anatomy. In 13 patients scanned using 16-MDCT, six different coronary anomalies were diagnosed [two absent left main, one single vessel left coronary artery (LCA), three LCA originating from the right (two with interarterial course), six right coronary artery originating from the left, one double left anterior descending (LAD)]. Mean diagnostic quality, recorded by two observers using a 5-point scale (1= non-diagnostic to 5= excellent diagnostic quality), resulted in a mean score of 3.73 (SD 1.19) without any non-diagnostic result. MDCT offers an accurate diagnostic modality to visualize the origin and course of anomalous coronary arteries by a three-dimensional display of anatomy. Shortcomings in CAG can be overcome by the use of contrast-enhanced MDCT.

Adult↗
PubMed2004

Achieved platelet aggregation inhibition after different antiplatelet regimens during percutaneous coronary intervention for ST-segment elevation myocardial infarction.

OBJECTIVES: To evaluate the extent of platelet aggregation inhibition in patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI), treated with different antiplatelet agents and dosages. BACKGROUND: The extent of platelet aggregation inhibition is an independent predictor of major cardiac events after elective PCI. In STEMI patients undergoing PCI, routine dose of antiplatelet agents may be associated with less effective platelet aggregation inhibition. METHODS: Patients were treated with clopidogrel before angiography and randomized to abciximab, tirofiban, high-dose tirofiban, or no glycoprotein (GP) IIb/IIIa inhibitor; GP IIb/IIIa inhibitor bolus, followed by maintenance infusion, was administered after angiography, but before PCI. Platelet aggregation inhibition was assessed before angiography, immediately after PCI, and 1 and 6 h afterwards. RESULTS: The total study population consisted of 112 patients. Platelet aggregation inhibition was variable for individuals and suboptimal for all agents, particularly in the periprocedural period. Only with high-dose tirofiban, mean periprocedural platelet aggregation inhibition exceeded 80%. Angiographic parameters after PCI were not different between the groups. No relationship was found between the level of platelet aggregation and parameters of PCI success (Thrombolysis In Myocardial Infarction frame count and myocardial blush grade), after combining the data from all four groups studied. CONCLUSIONS: Platelet aggregation inhibition in STEMI patients undergoing PCI, treated with antiplatelet agents, is variable and suboptimal for all agents and dosages studied. Only with high-dose tirofiban, mean periprocedural platelet aggregation inhibition exceeded 80%. However, no relationship of platelet aggregation inhibition and angiographic outcome was found in this patient cohort.

Abciximab↗
PubMed2004

Rat abdominal aorta stenting: a new and reliable small animal model for in-stent restenosis.

BACKGROUND: A high throughput animal model may enhance pathophysiological studies to mechanisms of in-stent restenosis (ISR). More and appropriate antibodies and transgenic and knockout strains are available in rats. Consequently, a model for ISR in the rat would be convenient for pathobiological studies. Here we present the full characteristics of a rat ISR model suitable for high throughput stent research. METHODS: The abdominal aorta of rats was separated from surrounding tissue and a BeStenttrade mark 2 or a Cyphertrade mark sirolimus-eluting stent was locally inserted. After 1, 3, 7, 28 and 56 days, the aortas were harvested, fixed, embedded and cut. Morphometric analysis was performed and inflammation scored. RESULTS: The neointimal area increased to a maximum after 28 days (0.55 +/- 0.08 mm(2)). Subsequently, the neointimal area slightly decreased. The injury score and the neointimal area were linearly correlated (r = 0.85, p < 0.01). Thrombus formation was present after 1 day. Leukocyte adherence was evident after 1 day, maximal after 3 days (93 +/- 21 cells/section) and decreased thereafter. The inflammation score increased after 3 days to a maximum after 7 days (1.37 +/- 0.06) and declined thereafter. After 28 days the Cypher sirolimus-eluting stent decreased the stenosis in comparison to the BeStent 2 (10.2 +/- 0.85 vs. 18.0 +/- 2.0%, respectively, p < 0.01). CONCLUSIONS: Stent deployment in the rat abdominal aorta results in thrombus formation, inflammation and neointimal formation. Moreover, there is a linear correlation between the injury score and the neointimal area. These responses resemble ISR events as seen in other animal models. Moreover, a known anti-restenotic stent also reduces neointimal formation in this model. Rat abdominal aorta stenting is a promising animal model for ISR, it is suitable for testing commercially manufactured stents and studying the pathophysiology of ISR.

Animals↗
PubMed2004

Dobutamine stress MRI. Part II. Risk stratification with dobutamine cardiovascular magnetic resonance in patients suspected of myocardial ischemia.

The aim of this study was to determine the prognostic value of dobutamine cardiovascular magnetic resonance (CMR) in patients suspected of myocardial ischemia. Clinical data and dobutamine-CMR results were analyzed in 299 consecutive patients. Follow-up data were analyzed in categories of risk levels defined by the history of coronary artery disease and presence of rest wall motion abnormalities (RWMA). Major adverse cardiac events (MACE) as evaluated end points included cardiac death, nonfatal myocardial infarction and clinically indicated coronary revascularization. Follow-up was completed in 214 (99%) patients with a negative dobutamine-CMR study (no signs of inducible myocardial ischemia) with an average of 24 months. The patients with a negative dobutamine-CMR study and RWMA showed a significantly higher annual MACE rate (18%) than the patients without RWMA (0.56%) ( P<0.001). Patients without RWMA showed an annual MACE rate of 2% when they had a history of coronary artery disease and <0.1% without a previous coronary event ( P<0.001). Dobutamine-CMR showed a positive and negative predictive value of 95 and 93%, respectively. The cardiovascular occurrence-free survival rate was 96.2%. In patients suspected of myocardial ischemia, dobutamine-CMR is able to assess risk levels for coronary events with high accuracy.

Cardiotonic Agents↗
PubMed2004

Prognostic assessment of patients with acute myocardial infarction treated with primary angioplasty: implications for early discharge.

BACKGROUND: The aim of this study was to create a practical score for risk stratification in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary angioplasty and to assess the feasibility of early discharge in low-risk patients. METHODS AND RESULTS: A prognostic score was built according to 30-day mortality rates in 1791 patients undergoing primary angioplasty for STEMI. For the identified low-risk patients without any contraindication to early discharge, we estimated and compared the costs of conventional care (prolonged 24-hour hospitalization) with the costs of shifting the care from inpatient to outpatient setting (early discharge) between 48 and 72 hours. Independent predictors of 30-day mortality included in the score were age, anterior infarction, Killip class, ischemic time, postprocedural Thrombolysis In Myocardial Infarction (TIMI) flow, and multivessel disease. This score was able to identify a large cohort (73.4%) of low-risk (score < or =3) patients, with a good discriminatory capacity (c statistic=0.907). The mortality rate was 0.1% at 2 days and 0.2% between 2 and 10 days in patients with a score < or =3. The incremental cost-effectiveness ratio for late discharge in low-risk patients was estimated at 1949.33. Therefore, this policy would save 1 life per 1097 low-risk patients, at additional costs of 194 933.33, in comparison with an early discharge policy. CONCLUSIONS: This score is a practical and useful index for risk stratification after primary angioplasty for STEMI, with a significant impact on clinical decision-making and the related costs. It reliably identifies a large group of patients at very low risk, who may safely be discharged early after primary angioplasty.

Aged↗
PubMed2004

Preprocedural TIMI flow and mortality in patients with acute myocardial infarction treated by primary angioplasty.

OBJECTIVES: The aim of the study was to evaluate the impact of preprocedural Thrombolysis In Myocardial Infarction (TIMI) flow on one-year mortality in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary angioplasty. BACKGROUND: Although there is an excellent outcome conferred by primary angioplasty in patients with STEMI, the prognostic role of early recanalization in these patients has yet to be investigated. METHODS: Our population is composed of 1,791 patients with acute myocardial infarction treated by primary angioplasty at our institution from 1994 to 2001. All angiographic, clinical, and follow-up data were prospectively collected. According to the TIMI risk score, patients were stratified in low- and high-risk groups. RESULTS: Preprocedural TIMI flow was related to postprocedural TIMI flow grade 3 (p = 0.002), myocardial blush grade 2 to 3 (p < 0.001), enzymatic infarct size (p < 0.001), predischarge ejection fraction (p < 0.001), and one-year mortality (p < 0.05). Multivariate analysis showed that preprocedural TIMI flow grade 3 was an independent predictor of one-year survival in high-risk patients (p < 0.05). CONCLUSIONS: This study shows that preprocedural TIMI flow grade 3 is an independent predictor of one-year survival in high-risk patients with acute myocardial infarction treated by primary angioplasty. These data suggest that all efforts should be made to obtain early and optimal restoration of antegrade flow, particularly in high-risk patients and when transportation to tertiary centers, with a conceivable further time delay, is required.

Aged↗
PubMed2004

Impaired myocardial perfusion is a major explanation of the poor outcome observed in patients undergoing primary angioplasty for ST-segment-elevation myocardial infarction and signs of heart failure.

BACKGROUND: The aim of the present study was to investigate the prognostic implication of myocardial perfusion in patients with ST-segment-elevation myocardial infarction (STEMI) and signs of heart failure, treated with primary angioplasty. METHODS AND RESULTS: Our population is represented by 1548 consecutive patients undergoing primary angioplasty for STEMI. Congestive heart failure was defined as Killip class >1 at admission. Killip class was linearly associated with myocardial perfusion, enzymatic infarct size, predischarge ejection fraction, and 1-year mortality rate. Myocardial blush was an independent predictor of 1-year mortality (RR [95% CI]=2.92 [1.37 to 6.23], P=0.005) in patients with advanced Killip class at presentation. CONCLUSIONS: Our study shows that patients with heart failure complicating STEMI have impaired myocardial perfusion, which accounts for the poor outcome observed in these patients. Further efforts should be aimed at improving myocardial perfusion, beyond epicardial recanalization, to further improve the outcome of these high-risk patients.

Aged↗
PubMed2004

Angiographic predictors of left ventricular ejection fraction after successful angioplasty in acute myocardial infarction: an angiographic risk score for use in the catheterization laboratory.

We investigated the value of angiographic parameters in patients with successful primary angioplasty using a simple angiographic risk score. In 608 consecutive patients, we assessed the infarct-related artery, antegrade flow before treatment, presence of distal embolization, and myocardial blush grade after coronary angioplasty. LAD-related infarction (OR = 8.4; 3 points), TIMI 0-2 flow before angioplasty (OR = 2.2; 1 point), myocardial blush 0 or 1 (OR = 2.5; 1 point), and distal embolization (OR = 2.2; 1 point) were independent predictors of left ventricular ejection fraction (LVEF) < or = 40% after successful angioplasty. Patients with 0 (minimum) or 1 point have LVEF of 49.5% +/- 8.4% and 30-day mortality of 0.8%. Patients with 2-3 points have LVEF of 44.9% +/- 10.3% and 30-day mortality of 2.8%. Patients with 4 points have LVEF of 38.2% +/- 10.8% and 30-day mortality of 2.7%. Patients with 5-6 (maximum) points have LVEF of 32.0% +/- 9.4% and 30-day mortality of 6.9%. A simple angiographic score predicts LVEF and mortality in patients when leaving the catheterization laboratory after successful primary angioplasty for acute myocardial infarction.

Angioplasty, Balloon, Coronary↗
PubMed2004

Prognostic value of admission glucose in non-diabetic patients with myocardial infarction.

BACKGROUND: Patients with acute myocardial infarction (AMI) who have diabetes have an increased risk of death. In nondiabetic patients, admission glucose levels may be a predictor of survival. However, data regarding admission glucose and long-term outcome in nondiabetic patients treated with reperfusion therapy for AMI are limited. METHODS: We investigated long-term clinical outcome in 356 consecutive nondiabetic patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention or thrombolysis as reperfusion therapy. Mean follow-up time was 8 +/- 2 years. The patients were divided on the basis of admission glucose level: group 1, <7.8 mmol/L; group 2, 7.8 to 11.0 mmol/L; and group 3, > or =11.1 mmol/L. RESULTS: Mortality rate in group 1 (n = 163) was 19.0%; in group 2 (n = 151), 26.5%; and in group 3 (n = 42), 35.7% (P <.05). Higher glucose levels were associated with larger enzymatic infarct sizes (P <.01) and more reduced residual left ventricular function (P <.05). Multivariate analysis showed that Killip class >1 at admission (OR, 2.9; 95% CI, 1.7 to 5.0; P <.001), age > or =60 years (OR, 2.4; 95% CI, 1.5 to 4.0, P =.001), thrombolysis as compared with percutaneous coronary intervention (OR, 1.7; 95% CI, 1.1 to 2.7, P =.02), admission glucose category (OR, 1.4; 95% CI, 1.0 to 1.9, P =.04), and anterior location (OR, 1.6; 95% CI, 1.0 to 2.6, 0.03) were independent predictors of long-term clinical outcome. CONCLUSIONS: Elevated admission glucose levels in nondiabetic patients treated with reperfusion therapy for ST-segment elevation myocardial infarction are independently associated with larger infarct size and higher long-term mortality rates.

Aged↗
PubMed2004

Sex-related differences in outcome after ST-segment elevation myocardial infarction treated by primary angioplasty: data from the Zwolle Myocardial Infarction study.

BACKGROUND: Several studies have found that among patients with ST-elevation myocardial infarction (STEMI) treated by thrombolysis, female sex is associated with a worse outcome. The aim of this study was to investigate sex-related differences in clinical and angiographic findings and in long-term outcome in patients with STEMI treated with primary angioplasty. METHODS: Our population is represented by 1548 consecutive patients with STEMI treated by primary angioplasty from April 1997 to October 2001. All clinical, angiographic, and follow-up data were prospectively collected. RESULTS: Among 1548 patients, 353 were women (22.8%). Female sex was associated with more advanced age, higher prevalence of diabetes, hypertension, more advanced Killip class, longer ischemia time, and smaller vessel caliber. No difference was observed in terms of procedural success, postprocedural epicardial flow, myocardial perfusion, ST-segment resolution, and enzymatic infarct size. At 1-year follow-up, female sex was associated with a significantly higher 1-year mortality rate at univariate (9.3% vs 4.9 %, RR [95% CI] = 1.79 [1.14 to 2.8], P = .002) but not at multivariate analysis (RR [95% CI] = 1.41 [0.86 to 2.32], P = NS). CONCLUSIONS: This study shows that in patients with STEMI treated by primary angioplasty, women are associated with higher mortality rate in comparison with men, mainly because of their high-risk profile and angiographic features. Female sex did not emerge as an independent predictor of death.

Age Factors↗
PubMed2004

Time-to-treatment significantly affects the extent of ST-segment resolution and myocardial blush in patients with acute myocardial infarction treated by primary angioplasty.

AIMS: The prognostic role of time-to-treatment in primary angioplasty is still a matter of debate. The aim of our study was to evaluate the relationship between time-to-treatment and myocardial perfusion in patients with ST-segment-elevation myocardial infarction (STEMI) treated by primary angioplasty. METHODS AND RESULTS: Our study population consisted of 1072 patients with STEMI treated by primary angioplasty from 1997 to 2001. Myocardial perfusion was evaluated by using ST-segment resolution and myocardial blush grade. Time-to-treatment was defined as the time from symptom-onset to the first balloon inflation. Time-to-treatment was significantly associated with the extent of ST-segment resolution, myocardial blush grade, enzymatic infarct size, and 1-year mortality. After adjustment for baseline confounding factors, time-to-treatment was still associated with impaired ST-segment resolution (adjusted OR [95% CI]=1.01 [1.01-1.02], p<0.001) and myocardial blush (adjusted OR [95% CI]=1.01 [1.01-1.02], p<0.0001). CONCLUSIONS: This study shows that in patients with STEMI treated by primary angioplasty prolonged ischaemic time is associated with impaired myocardial perfusion, larger infarct size, and higher 1-year mortality. Therefore, all efforts should be made to shorten ischaemic time as much as possible to achieve better myocardial perfusion and myocardial salvage in primary angioplasty for STEMI.

Aged↗
PubMed2004

Long-term, cause-specific mortality after myocardial infarction in diabetes.

AIMS: To compare long-term, cause-specific mortality after reperfusion therapy for ST segment elevation myocardial infarction (STEMI) in patients with and without diabetes. METHODS AND RESULTS: Patients with STEMI (n = 395) were randomised to intravenous streptokinase (SK) or primary percutaneous coronary intervention (PCI). Median follow-up was 7.5 years (interquartile range 5.6-8.5). A total of 74 patients (19%) had diabetes. Reduced left ventricular ejection fraction (<40%) after STEMI was more often observed in patients with diabetes (27% vs. 15%, P = 0.02). Patients with diabetes had a higher total mortality compared to patients without diabetes (HR 2.4; P < 0.001). Multivariate analysis confirmed that diabetes was an independent risk factor for long-term mortality (HR 2.3; P < 0.001). The incidence of sudden death was comparable in both patient groups (HR 1.6; P = 0.23). The increased mortality in patients with diabetes was mainly caused by heart failure (HR 3.1; P = 0.004). In patients with diabetes, primary PCI was associated with an improved prognosis. CONCLUSIONS: Despite reperfusion therapy, STEMI patients with diabetes have an increased long-term mortality. This is due to death by heart failure and not by an increase in sudden death. Primary PCI is associated with an improved prognosis, particularly in patients with diabetes.

Angioplasty, Balloon, Coronary↗
PubMed2004

Facilitation of primary coronary angioplasty by early start of a glycoprotein 2b/3a inhibitor: results of the ongoing tirofiban in myocardial infarction evaluation (On-TIME) trial.

AIM: Although primary angioplasty is effective despite additional transportation delay, improved patency before PCI might be obtained by starting pharmacological pre-treatment before transportation. METHODS AND RESULTS: From June 2001 to November 2002, 507 patients with acute myocardial infarction, who were transferred to a PCI centre, were randomised to early, pre-hospital initiation of Tirofiban (Early) or to initiation in the catheterisation laboratory (Late). The primary end-point was TIMI flow grade 3 of the infarct-related vessel (IRV) at initial angiography, as assessed by an independent core-lab. The effect of Tirofiban on each TIMI flow component, the presence of thrombus at initial angiography and pre-PCI myocardial blush grade were secondary end-points. A large proportion of patients (41%) was diagnosed and randomised in the ambulance, without intervention of a physician. In the Early group, Tirofiban was administered a median of 59 min (range 11-178 min) earlier than in the Late group. At initial angiography, TIMI 3 flow was present in 19% the Early group and in 15% in the Late group (P = 0.22). The combined incidence of TIMI 2 or 3 flow was present in 43% in the Early group and in 34% in the Late group, respectively (P = 0.04). Thrombus or a fresh occlusion was present in 60% and 73% in the Early and Late group, respectively (P = 0.002). A pre-PCI myocardial blush grades 2 or 3 was more often present in the Early group (30% vs. 22%, P = 0.04). However, no difference in TIMI 3 flow or myocardial blush grade was found between the groups, post-PCI. At one-year follow-up, the combined incidence of death or recurrent MI was not different between the groups (7.0% vs. 7.0%, P = 0.99). CONCLUSION: Early initiation of Tirofiban did not improve initial TIMI 3 flow of the IRV significantly. Despite a better patency (TIMI 2 or 3 flow), a lower prevalence of thrombus or fresh occlusion and a better myocardial perfusion in the infarct-related region pre-PCI, no beneficial effect on post-PCI angiographic or clinical outcome was found, as compared to initiation of Tirofiban in the catheterisation laboratory.

Aged↗