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C Van De Wiele

Publications and source records attributed to C Van De Wiele.

16 recordsLinked to original sources
PubMed2007

Poststress left ventricular ejection fraction is an independent predictor of major cardiac events in patients with coronary artery disease and impaired left ventricular function.

AIM: The aim of this study was to investigate the prognostic value of myocardial perfusion and function SPECT imaging in patients with coronary artery disease (CAD) and poor left ventricular (LV) function. METHODS: We studied 261 patients (231 men, age 66+/-10 years) with CAD and a resting LV ejection fraction (LVEF) <or= 40% assessed during myocardial gated SPECT. Perfusion defect extent was calculated using 4D-MSPECT software (Michigan University). Ischemia scoring was performed visually. Considered end points were: 1) major adverse cardiac events (MACE) (cardiac death, non-fatal myocardial infarction or late revascularization), 2) MACE or the need for hospitalization due to heart failure (MACE-HF) and 3) cardiac death or non-fatal myocardial infarction. RESULTS: During a median follow-up of 31 months, 52 patients (20%) died (35 cardiac deaths), 50 (19%) developed a MACE and 69 (26%) a MACE-HF. In a clinical model, diabetes and angina status were the only predictors of MACE (chi-squared=19.3; P<0.001). By multivariate analysis, poststress LVEF (chi-squared-gain of 6.4; P=0.008) and presence of ischemia (chi-squared-gain of 5.8; P=0.018) were predictive of MACE. Similarly, diabetes mellitus (chi-squared=12.1; P<0.001), poststress LVEF (chi-squared-gain of 5.5; P=0.019) and presence of ischemia (chi-squared-gain of 4.3; P=0.044) were independent predictors of MACE-HF. Diabetes mellitus (chi-squared=17.8; P<0.001), presence of angina complaints (chi-squared-gain of 6.8; P=0.028) and poststress LVEF (chi-squared-gain of 6.3; P=0.008) were independent predictors of cardiac death or non-fatal myocardial infarction. CONCLUSION: In patients with impaired LV function and CAD, poststress LVEF is an independent predictor of future cardiac events.

Aged↗
PubMed2005

A forum for IRIST.

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International Agencies↗
PubMed2003

Validation of planar and tomographic radionuclide ventriculography by a dynamic ventricular phantom.

Although there is increasing interest in the automatic processing of tomographic radionuclide ventriculography (TRV) studies, validation is mainly limited to a comparison of TRV results with data from planar radionuclide ventriculography (PRV) or gated perfusion single photon emission computed tomography (SPECT). The aim of this study was to use a dynamic physical cardiac phantom to validate the ejection fraction (EF) and volumes from PRV and TRV studies. A new dynamic left ventricular phantom was constructed and used to obtain 21 acquisitions in the planar and tomographic mode. The directly measured volumes and EFs of the phantom during the acquisitions were considered as the gold standard for comparison with TRV and PRV. EFs were calculated from PRV by background-corrected end-diastolic and end-systolic frames. Volumes and EFs were calculated from TRV by region growing with different lower thresholds to search for the optimal threshold. EF from PRV correlated significantly with the real EF (r=0.94, P=0.00). The optimal threshold value for volume calculation from TRV in 336 cases was 50% (r=0.98, P=0.00) yielding the best slope after linear regression. When considering these calculated end-diastolic and end-systolic volumes, EF correlated well (r=0.99, P=0.00) with the real EF, and this correlation was significantly (P=0.04) higher than that of the EF from PRV. Our experiments prove that EF measured by TRV yields more accurate results compared with PRV in dynamic cardiac phantom studies.

Aircraft↗
PubMed2002

The clinical value of nuclear medicine in the assessment of irradiation-induced and anthracycline-associated cardiac damage.

Two groups of patients, those treated for Hodgkin's disease and breast cancer, are particularly at risk of developing late myocardial damage, since radiotherapy (RT) techniques for both patient groups may include (large) parts of the heart, and adjuvant systemic therapy is frequently administered to these patients, in particular anthracycline-containing chemotherapy. Available literature on the monitoring and prediction of RT-induced and anthracycline-associated cardiac damage using nuclear medicine techniques is presented. Based on relevant studies, the risk of overall cardiac disease post-RT and overt congestive heart failure during anthracycline-containing chemotherapy is probably low. Conventional nuclear medicine imaging, i.e. myocardial perfusion scintigraphy, may be of complementary use to echocardiographical evaluation for routine follow-up after RT with modern techniques, in a subgroup of patients with known cardiovascular risk factors. Left ventricle ejection fraction (LVEF) measurements, as assessed by radionuclide angiography for the monitoring of anthracycline-associated cardiac injury, are not very sensitive and early detection will probably be enhanced by combining LVEF measurements with other cardiac function parameters. Also, it may be expected that nuclear medicine techniques using molecular radioligands will constitute an essential future step in the evaluation of subclinical cardiac injury afforded by the combined effect of RT and cardiotoxic chemotherapy.

Anthracyclines↗
PubMed2002

Biodistribution and displacement studies of the selective 5-HT2A receptor antagonist 123I-5-I-R91150 in the normal dog.

There is increasing interest in mapping receptors in vivo by using functional imaging modalities such as single photon emission tomography (SPET) and positron emission tomography (PET). Since SPET is a more accessible functional imaging modality than PET and, overall, it is more economical, radioligands suitable for this technique are in greater demand. Recently, 123I-5-I-R91150, a radioligand with high selectivity and affinity for 5-HT(2A) receptors in the brain, was introduced for SPET. This study reports on the whole-body distribution and brain uptake of the selective 123I-5-I-R91150 ligand in four normal dogs. The frontal to cerebellar ratio of uptake in time was determined in three dogs. Time-activity curve of venous blood was determined in one dog. Maximal global brain uptake was found at 10-60 min post-injection. Higher brain uptake was noted in the frontal cortical areas compared to the cerebellum. The frontal-cerebellar ratio reached the highest values at 90-180 min. Reversibility and pharmacological selectivity of ligand binding was demonstrated through displacement and blocking studies with the 5-HT(2A) receptor antagonist ketanserin. This study demonstrates that the specific 5-HT(2A) iodinated ligand can be used for imaging and semi-quantification of the 5-HT(2A) receptors in the canine brain in vivo by using SPET.

Animals↗
PubMed2002

18FDG PET versus high-dose 67Ga scintigraphy for restaging and treatment follow-up of lymphoma patients.

To date, only one published study has directly compared 67Ga scintigraphy (low dose, planar) with planar dual-head gamma camera 18F-fluorodeoxyglucose (18FDG) imaging for the purpose of treatment follow-up monitoring in lymphoma patients, and no data on restaging are available. The present study reports the direct comparison of high-dose (297-370 MBq) 67Ga planar and single photon emission computed tomography (SPECT) imaging and conventional 18FDG positron emission tomography (PET) for restaging and treatment follow-up of lymphoma patients versus a gold standard consisting of morphological imaging, including plain radiography and computed tomography (CT) scanning, bone marrow examination and long-term follow-up (<12 months). Sixteen patients, 10 with non-Hodgkin's lymphoma and six with Hodgkin's disease, were included (10 men, six women; median age, 43 years; range, 16-64 years). The median follow-up time was 27 months (range, 12-34 months). In two patients, 67Ga and 18FDG PET (370 MBq) were performed twice, resulting in 18 cross-sectional episodes. In 11 episodes, the results obtained by both imaging modalities were in agreement with regard to the presence or absence of disease when compared with the gold standard. However, the abnormalities found on 18FDG PET were always more extensive. In two episodes, 67Ga imaging normalized after treatment, whereas PET showed significant regression followed by subsequent normalization. In four additional episodes, 67Ga images were negative, whereas 18FDG PET visualized non-tumour-related pathology, such as lung infection, rib fracture or dense thymic tissue. In one gold standard-negative patient, the underlying cause of sternal FDG uptake remained undetermined. The data presented, although limited in number, suggest that 18FDG PET performs better than Ga imaging in monitoring lymphoma disease status. However, a correlation with clinical history and a knowledge of the characteristics of benign lesions are mandatory. Further studies are recommended.

Adolescent↗
PubMed2001

99Tc(m) labelled HL91 versus computed tomography and biopsy for the visualization of tumour recurrence of squamous head and neck carcinoma.

This phase I pilot study reports on (1) the safety and feasibility of 99Tc(m)-HL91, an amine oxime core radioligand that has shown oxygen dependent binding, and imaging; and (2) its usefulness for the visualization of local tumour recurrence of a biopsy proven squamous cell carcinoma of the head and neck (SCCHN) as compared to spiral computed tomogaphy (CT) and biopsy. Nine men (mean age 33 years, range 34-74 years) were prospectively included. For safety measurements, vital signs were recorded and serum chemical analysis carried out, with a complete blood cell count and urine analysis, and an ECG was performed prior to injection of 99Tc(m)-HL91 and repeated during the investigation. Single photon emission computed tomography (SPECT) scans of the head and neck, and of a standard, were performed at 2 h and 4 h post-injection of 740 MBq 99Tc(m)-HL91. Tumour-to-normal tissue background (T/N) ratios and percentage uptake were measured for all 99Tc(m)-HL91 scans. Spiral CT scans were obtained using a Somaton 4+ Siemens scanner within 1 week from the 99Tc(m)-HL91 scans. Based on CT and the 99Tc(m)-HL91 scan findings guided biopsies were performed. No adverse or subjective side effects were noticed. Vital signs, ECG findings, clinical laboratory, blood and urine assays remained stable in all patients. Spiral CT suggested local recurrence in 5/9 patients accompanied by nodal involvement in three, all of which proved positive on biopsy. 99Tc(m)-HL91 scintigraphy was false positive in one patient and true positive (TP) in 3/5 local recurrences and two out of three sites of lymph node involvement depicted by spiral CT. The mean T/N ratios at 2 h and 4 h in TPs were 1.28 (range 1.1-1.66) and 1.40 (range 1.0-1.6), respectively. The corresponding absolute percentages of 99Tc(m)-HL91 lesional uptake at 2 h and 4 h were mu = 0.05% (SD = 0.03%) and mu = 0.048% (SD = 0.035%). The findings suggest 99Tc(m)-HL91 is a safe radioligand and that metabolic binding in a large fraction but not all of local SCCHN recurrences may be expected. The inference that tumour 99Tc(m)-HL91 avidity could be a non-invasive measure of tumour hypoxia deserves however independent confirmation with needle oximetry.

Adult↗
PubMed2000

Adaptive response in patients treated with 131I.

UNLABELLED: The aim of this study was to investigate whether an adaptive response (defined as the induction of radiation tolerance after a small dose of radiation) could be observed in peripheral blood lymphocytes of patients treated with 1311 for thyroid disease. METHODS: For each patient, blood samples were taken immediately before and 1 wk after 131I administration. Each blood sample was divided into 3 fractions and the fractions were subsequently irradiated in vitro with 0, 0.5, and 1.0 Gy 60Co gamma-rays. After blood culture for 70 h, cells were harvested and stained with Romanowsky-Giemsa and micronuclei were counted in 1000 binucleated cells. The increase in micronuclei by the in vitro irradiation of the blood samples taken before and after therapy was compared. In this setup, an adaptive response is represented by a significant decrease of the in vitro induced micronucleus yield after therapy compared with that before therapy. The iodine therapy can be considered as an in vivo adaptation dose, after which the subsequent in vitro irradiation acts as a challenge dose. To investigate the reproducibility of the method, 2 subsequent blood samples of healthy volunteers were taken 7 d apart. Irradiation and cell culture were performed as described. RESULTS: In 8 of 20 patients, a significant (P = 0.0002) decrease was found in the in vitro induced micronucleus yield in the blood sample taken 1 wk after 1311 administration compared with that of the blood sample taken before therapy. No significant (P > 0.1) differences were observed between these 8 patients and the other patients when the number of micronuclei induced in vivo by the iodine treatment and the resulting equivalent total body dose were compared. None of the control subjects showed a significant change in micronucleus yield after in vitro irradiation between both blood samples taken 1 wk apart. CONCLUSION: The iodine treatment can act as an in vivo adaptation dose and can induce an adaptive response that is observed by a decrease of the cytogenetic damage in peripheral blood lymphocytes after in vitro irradiation as a challenge dose. A large interindividual difference was observed.

Adaptation, Physiological↗
PubMed1999

QT dispersion is not related to infarct size or inducibility in patients with coronary artery disease and life threatening ventricular arrhythmias.

OBJECTIVE: To relate QT parameters to infarct size and inducibility during electrophysiological studies. DESIGN: Analysis of a prospective register. SETTING: University hospital. PATIENTS: 64 patients with coronary artery disease and documented life threatening ventricular arrhythmias. INTERVENTIONS: Measurements of QT-max, QTc-max, and QT dispersion (QT-d) on a simultaneous 12 lead ECG (50 mm/s). Estimation of myocardial infarct size with radionuclide left ventricular ejection fraction (LVEF), echocardiography (left ventricular end diastolic diameter, LVEDD), and a defect score based on a quantitative stress redistribution 201-thallium perfusion study. Electrophysiological study to assess inducibility. RESULTS: Mean (SD) QT parameters were: QT-max 440 (50) ms, QTc-max 475 (46) ms, and QT-d 47 (20) ms. Mean (SD) estimates of infarct size were: LVEF 34 (13)%, LVEDD 61 (9) mm, and defect score 18 (11). There was no significant correlation between any index of infarct size and QT parameters. QT parameters were not significantly different between patients with inducible (n = 57) and non-inducible arrhythmias (n = 7) (QT-max: 416 (30) v 443 (51) ms, p = 0.18; QTc-max 485 (34) v 473 (47) ms, p = 0.34; QT-d 47 (12) v 47 (21) ms, p = 0.73). Non-inducible patients had a significant lower defect score: 8 (9) v 19 (11), p = 0.02, but comparable LVEF: 38 (12)% v 34 (12)%, p = 0.58, and LVEDD: 54 (10) v 61 (8) mm, p = 0.13. CONCLUSIONS: QT parameters are not influenced by infarct size and do not predict inducibility during electrophysiological study in patients with coronary artery disease and malignant ventricular arrhythmias. In contrast, the amount of scar tissue determined by perfusion imaging is strongly correlated with inducibility.

Aged↗