Biomedical subjects

J Verbist

Publications and source records attributed to J Verbist.

At least 19 recordsLinked to original sources

PubMed2006

Does free cell area influence the outcome in carotid artery stenting?

OBJECTIVES: To identify if carotid stent design, especially free cell area, impacts on the 30-day rates for stroke, death and TIA after carotid artery stenting (CAS). MATERIAL AND METHODS: A CAS database of 3179 consecutive CAS patients was retrospectively assessed. The distribution of neurological complications were analysed for association with the different stent types and designs. Events where subdivided into procedural and postprocedural events. RESULTS: The overall combined rate of TIA, stroke and death was 2.8% at 30 days (late events 1.9%). The post-procedural event rate analyzed for differences stents varied from 1.2% using BSCI Carotid Wallstent to 5.9% using Medtronic Exponent. The late event rates varied from 1.2% to 3.4% for free cell areas <2.5mm(2) and >7.5mm(2) respectively (p<0.05). Post-procedural event rate was 1.3% for closed cells and 3.4% for open cells. All these differences were highly pronounced among symptomatic patients (p<0.0001). CONCLUSIONS: After carotid stenting, complication rates vary according to stent type, free cell area and cell design. In the symptomatic population (and also in the total population), post-procedural complication rates are highest for the open cell types and increase with larger free cell area.

Blood Vessel Prosthesis Implantation↗

PubMed2006

Review of stents for the carotid artery.

The individual characteristics of a stent may make it an attractive choice in some circumstances, but render it a less desirable option in others. The applicability depends primarily on the arterial anatomy and the specific details of the lesion being treated. A careful assessment by the interventionalist is required to select the proper type of stent that is of appropriate size. Certainly, personal preferences and familiarity with a specific device may legitimately influence the decision to choose one stent over another. Finally, stent design can play a role in the selection procedure. Although carotid stents are often functionally equivalent in the clinical setting and have been used successfully to treat a wide variety of lesions, a basic knowledge of stent geometry can contribute to make up your mind in certain carotid cases.

Angioplasty↗

PubMed2006

Percutaneous transluminal angioplasty for treatment of ''below-the-knee'' critical limb ischemia: early outcomes following the use of sirolimus-eluting stents.

AIM: We investigated the safety and efficacy of sirolimus-eluting stents in the treatment of patients with severe below-the-knee' critical limb ischemia. METHODS: Between October 2004 and January 2005 we performed 20 percutaneous transluminal angioplasty procedures on 18 patients (7 female, 11 male, mean age 72.8 years), implanting 24 sirolimus-eluting stents. At pre-procedure, 12 patients (66.7%) presented with a Rutherford Category 4, 4 (22.2%) with Category 5 and 2 (11.1%) with Category 6. The majority of patients (72.2%, n=13) were non-smokers and 77.8% (n=14) presented with hypercholesterolemia. Calcification was present in 52.2% (n=12) of lesions. Pre-dilation was performed in half the patients. The majority of lesions (95.7%, n=22) were treated with a single sirolimus-eluting stent. Two patients underwent 2 procedures, each one receiving 2 sirolimus-eluting stents. Clinical examination and quantitative vascular analysis were performed in all patients at discharge and at 6-month follow-up. RESULTS: Percutaneous transluminal angioplasty was successfully performed on all 18 patients. The mean stent length and stent diameter were 30.29 mm and 3.23 mm, respectively. Mean follow-up was 256 days (170-368 days). At the 6-month follow-up, the minimum lumen diameter as measured by Quantitative Vessel Analysis was 2.39 mm with an attendant LLS of 0.38 mm. The overall 6-month survival and limb salvage rate were 94.4% and 94%, respectively. CONCLUSIONS: Our results suggest that treatment with sirolimus-eluting stents can be considered as an effective and safe treatment of patients with critical ischemia.

Adult↗

PubMed2006

Balloon-expandable, radially reinforced ePTFE relining of the superficial femoral artery after remote endarterectomy.

AIM: The aim of this paper was to evaluate the mid-term results of remote endarterectomy and balloon-expandable, radially reinforced ePTFE endograft uplining of the superficial femoral artery (SFA) for long occlusions. METHODS: One hundred and two limbs in 92 patients were included in this prospective, multicenter study. Indications were disabling claudication (n=74), restpain (n=10) and tissue loss (n=16) due to an SFA occlusion of at least 10 cm in length. Remote endarterectomy of the SFA using a modified ringcutter in an over-the-wire technique, was followed by implantation of a balloon-expandable Enduring endovascular graft. Control visits were performed at 1, 3 and 6 months postprocedure and every half year from then on. Follow-up protocol included physical examination, Doppler ankle-brachial index measurement and, in case of doubt, duplex examination. RESULTS: A technical success rate of 98% was achieved. Mean follow-up was 36 months. Four patients were lost to follow-up and 17 patients died of nondevice-related causes. The primary, primary assisted and secondary patency rates were 68%, 73% and 97.5% at 1 year and 50%, 60%, and 89% at 3 years, respectively. CONCLUSION: Although technical success rate is high and early patency rates are good, mid-term results are inferior to those of conventional femoro-popliteal synthetic bypass grafts. In order to become competitive to conventional bypass surgery, further technical refinements will be necessary, especially to overcome the problem of stenoses at the distal transition zone.

Adult↗

PubMed2006

Will absorbable metal stent technology change our practice?

Peripheral stents aim to support revascularization procedures of intravascular stenoses by mechanically preventing vessel recoil and counteracting pathophysiologic processes of luminal re-narrowing triggered by procedural injury of the vessel wall. Despite improvements in stenting techniques and concomitant medication, repeated intervention due to target lesion re-stenosis is necessary on a significant percentage of patients. The permanent presence of an artificial implant plays a prominent role in the discussion of mechanisms causing in-stent restenosis. Permanent metallic implants pose the risk of a continuous interaction between non-absorbable stent and surrounding tissue, leading to physical irritation, long-term endothelial dysfunction, or chronic inflammatory reactions. In addition, there is a risk of stent fracture due to external mechanical forces. To overcome these shortcomings, technology of stenting has moved towards the development of temporary implants composed of biocompatible materials which mechanically support the vessel during the period of high risk for recoil and then completely degrade in the long-term perspective. This removes a potential trigger for late restenosis.

Absorbable Implants↗

PubMed2006

Results with heparin bonded polytetrafluoroethylene grafts for femorodistal bypasses.

AIM: Expanded polytetrafluoroethylene (ePTFE) grafts are commonly used for femoropopliteal (FP) and femorocrural (FC) bypass grafting. Especially in below-knee (BK) reconstructions, patency is often inferior to the outcome in patients eligible for venous bypass grafting. This study assesses whether the Carmeda BioActive Surface (CBAS), which employs covalent end-point linkage to retain heparin on the device surface, as it is used on the Propaten vascular graft successfully, can prolong patency. METHODS: From June 2002 to December 2005, 138 patients (97 men and 41 women; mean age: 73 years) received the CBAS-ePTFE graft for 153 infrainguinal bypass procedures. Seventy-five above-knee (AK) and 78 BK (including 37 FC) procedures were performed. Follow-up evaluations consisted of clinical examinations, ultrasonographic studies, and distal pulse assessments. Patency and limb salvage rates were assessed by using life-table analyses. RESULTS: The overall primary and secondary 2-year patency rates were 73.6% and 86%, respectively. Two-year primary patency rates according to bypass type were 76.2%, 72.6%, and 68.9% for AK FP, BK FP, and FC bypasses, respectively; the corresponding secondary patency rates were 87.5%, 87.8%, and 79.4%. The 2-year limb salvage rate in patients with critical limb ischemia (n=68) was 89.9%. CONCLUSION: Our findings show that CBAS-ePTFE bypass grafts appear to give prolonged patency rates and indicate that the use of this graft may represent a viable alternative for BK bypasses, which have traditionally yielded less than desirable outcomes. A prospective randomized trial is required to provide more definitive information about the graft's patency and limb salvage performance.

Aged↗

PubMed2005

Complex thoracic aortic aneurysm: a combined open and endovascular approach.

The authors wish to describe a combined open and endovascular approach to repair a complex thoracic aortic aneurysm. A 72-year-old man with chronic obstructive pulmonary disease, aortic valvular insufficiency and diffuse thoracic aortic aneurysm underwent aortic valve and ascending aorta replacement by a Bentall-procedure and replacement of arch aneurysm using the elephant trunk technique, performed in a first procedure. During the second procedure, endovascular stenting of the descending thoracic aorta was done. Only a few similar case reports have been presented. Endovascular repair after an elephant trunk procedure for complex thoracic aortic aneurysms is an elegant approach to deal with such mega aortas. Further research is necessary to compare open and endovascular repair and to determine long-term follow-up with regard to endoleaks and mortality.

Aged↗

PubMed2005

Endovascular treatment strategies for supra-aortic arterial occlusive disease.

Because of the focal nature of stenoses or occlusions in the supra-aortic vasculature, the high blood-pressures in this area and the very low morbidity rates related to percutaneous therapy have largely replaced surgical revascularization as the initial treatment of choice for patients with supra-aortic arterial occlusive disease. The initial technical success and durability of percutaneous angioplasty (PTA) and stenting in these lesions is excellent. Nevertheless several factors can make PTA and stenting a complex procedure that requires advanced endovascular skills for a successful outcome. Profound knowledge of surgical reconstruction techniques or extra-anatomic bypasses remains mandatory, as it is occasionally required for failure of endovascular techniques or if contraindications exist.

Angiography↗

PubMed2005

Does carotid artery stenting work on the long run: 5-year results in high-volume centers (ELOCAS Registry).

AIM: Although the first long-term results of Carotid Artery Stenting (CAS) became available only recently, CAS has become an accepted treatment for carotid artery disease. We report CAS data up to 5 years, both late stroke rate and patency rates as observed in 4 high-volume European centers. METHODS: Between February 1, 1993 and December 31, 2004, 2 172 patients were selected over the 4 participating centres, with intention to treat endovascularly. Conscientious follow-up was done according to the in-hospital stipulations of each centre and was entered into a database both retrospectively and prospectively. Long-term restenosis and stroke-death rates were investigated and statistically analysed and stratified using the Kaplan-Meier method. RESULTS: Of the 2 172 patients with intention to treat 2 165 (99.7%) were technically successful. Of these 306 (14.1%) were performed without and 1 859 (85.9%) with embolic protection device (EPD); 96 patients (4.4%) received balloon dilation only and stenting was performed in 2 069 (95.6%) cases. Kaplan-Meier analysis of major stroke/all death and of significant restenosis (>50%) for the total population showed stroke/death rates of 4.1% (nar=1 356), 10.1% (nar=476) and 15.5% (nar=138); and restenosis rates of 1% (nar=1 363), 2% (nar=480) and 3.4% (nar=139), after 1, 3 and 5 years respectively. CONCLUSIONS: The patency and stroke/death rates resulting from our database analysis are pleasing and indicate that CAS also on longer term is a valuable treatment method for carotid artery disease. Due to the fact that our dataset contains prospective as well as retrospective data, it may have its limitations. Until this moment, data indicating that certain patient subgroups are at increased risk for neurological complications and in-stent restenosis during and after CAS are sparse. Further multivariant analysis on this unique dataset is mandatory in order to identify any potential links in between plaque morphology, preprocedural neurological complications, risk factor distribution, procedural steps and clinical outcome.

Adult↗

PubMed2004

Choice of protection devices in carotid angioplasty. Two case reports.

Patient selection is of the utmost importance with all endovascular procedures. It is equally important to select the appropriate protection device during carotid angioplasty/stenting (CAS). CAS in two patients was unsuccessful due to the chosen protection device. Occlusion of the external carotid artery while deploying a Parodi Anti-Embolic-System Device (PAEC - ArteriA) resulted in cerebral ischaemia. Conversion to the Angioguard System (Cordis) made carotid angioplasty possible, but was complicated by thrombosis of the filter. In the second case it was impossible to negotiate tortuous vessels with the Angioguard system. Our experience illustrates that both devices have limitations. Choosing the wrong device may have serious consequences.

Aged↗

PubMed2000

Postoperative pain management and recovery after remifentanil-based anaesthesia with isoflurane or propofol for major abdominal surgery. Remifentanil Study Group.

We have assessed if recovery times after morphine or fentanyl, given before terminating remifentanil anaesthesia with isoflurane or propofol, are compromised. We studied patients undergoing elective, major abdominal surgery, allocated randomly to receive remifentanil and isoflurane (n = 277) or remifentanil and propofol (n = 274) anaesthesia. Twenty-five minutes before the end of surgery, patients received fentanyl 0.15 mg or morphine 15 mg in a randomized, double-blind manner followed by a second dose (fentanyl 0.05 mg, morphine 7 mg) for moderate or severe pain in recovery. Recovery was rapid and at an Aldrete score > or = 9 (median 12-15 min), 42-51% of patients reported none or mild pain. However, 26-35% of patients reported severe pain and > 90% required a second dose of opioid within 21-27 min after anaesthesia.

Abdomen↗

PubMed1997

Myasthenia gravis associated with thymolipoma: a case report.

A 31-year-old patient with a 2-year history of myasthenia gravis underwent resection of a mass in the anterior mediastinum. On histological examination, the tumour proved to be a thymolipoma. The association of thymolipoma with myasthenia gravis is rare. To our knowledge this is the 12th case reported. It is however the first in which histological examination revealed the presence of germinal centres. The tumour measured 28 x 14 x 2 cm and weighted 340 gr. This is by far the largest thymolipoma associated with myasthenia gravis reported. As in all previously published cases, the myasthenia associated symptoms improved significantly after surgery. In this case improvement occurred within weeks. In general, benefit after thymectomy is delayed until months to years.

Adult↗

PubMed1997

Pseudoaneurysm of the inferior epigastric artery.

Abdominal wound closure with safety retention sutures can cause intestinal obstruction, fistula, skin necrosis and rarely pseudoaneurysms of the inferior epigastric artery (IEA) (1, 2, 3). We report the case of a man presenting with a pseudoaneurysm of the IEA after traumatic extraction of retention sutures, successfully treated by surgical ligation of the feeding vessels. The importance of contrast enhanced CT and duplex colour Doppler sonography in differential diagnosis of postoperative abdominal wall masses is discussed, as well as possibilities and risks in the treatment of false aneurysms of the IEA.

Abdominal Pain↗

PubMed1993

Expression of Ca2+ binding proteins of the sarcoplasmic reticulum of striated muscle in the endoplasmic reticulum of pig smooth muscles.

The Ca2+ binding proteins in the lumen of intracellular Ca2+ stores differ between muscle and non-muscle cells, indicating a specific role of these proteins in intracellular Ca2+ regulation. Since smooth muscle cells possess both muscle and non-muscle characteristics, we have studied the presence and the differential expression of the muscle-type Ca2+ binding proteins--calsequestrin, sarcalumenin, and the histidine-rich Ca2+ binding protein (HCP)--in several smooth muscle tissues from the pig. Western blot analysis showed that among the smooth muscles studied, the cardiac isoform of calsequestrin is expressed at the highest levels in the stomach. Calsequestrin was present at lower levels in ileum and trachea, whereas this protein was undetectable in aorta and main pulmonary artery. The total amount of calsequestrin in the stomach was estimated to be 20-30-times lower than in the pig heart. Whereas calsequestrin from pig presented the same apparent M(r) in sodium dodecyl sulphate polyacrylamide gels as the well characterized protein from rabbit, the apparent M(r) of both sarcalumenin and HCP was lower in pig than in rabbit. The presence of HCP was demonstrated in pig stomach and ileum, while sarcalumenin was detected only in the stomach. These results demonstrate further biochemical differences between smooth muscle cells of large blood vessels and those of the digestive tract. The present findings on the differential distribution of muscle-type Ca2+ binding proteins are discussed in relation to biochemical and functional differences between these smooth muscle cells.

Animals↗

PubMed1991

Phosphoinositide-protein interactions of the plasma-membrane Ca2(+)-transport ATPase as revealed by fluorescence energy transfer.

Fluorescence energy transfer has been used to study the interaction of various phospholipids with the erythrocyte (Ca2+ + Mg2+)-ATPase. The fluorescence energy transfer between tryptophan residues of the (Ca2+ + Mg2+)-ATPase purified from erythrocytes and pyrene-labelled analogues of phosphatidylcholine (Pyr-PC), phosphatidylinositol (Pyr-PI), phosphatidylinositol 4-phosphate (Pyr-PIP), phosphatidylinositol 4,5-bisphosphate (Pyr-PIP2), phosphatidylglycerol (Pyr-PG) and phosphatidic acid (Pyr-PA) was measured. A positive correlation was found between the number of negative charges on the phospholipids (PIP2 greater than PIP greater than PA greater than PI = PG greater than PC) and the potency of their pyrene-labelled analogues to act as quantum acceptors in fluorescence energy transfer from the tryptophan residues of the (Ca2+ + Mg2+)-ATPase. This is the first time that a physical interaction between PIP/PIP2 and an intrinsic membrane protein has been demonstrated. The dependence of the energy transfer on the number of negative charges of the phospholipids closely resembles the previously demonstrated charge dependence of the enzymatic activity of the (Ca2+ + Mg2+)-ATPase (Missiaen, L., Raeymaekers, L., Wuytack, F., Vrolix, M., Desmet, H. and Casteels, R. (1989) Biochem. J. 263, 687-694). It is concluded that the stimulation of the (Ca2+ + Mg2+)-ATPase activity by negatively charged phospholipids is based on a binding of these lipids to the (Ca2+ + Mg2+)-ATPase and that the negative charges are a major modulatory factor for this interaction.

Animals↗

PubMed1990

Expression of endoplasmic-reticulum Ca2(+)-pump isoforms and of phospholamban in pig smooth-muscle tissues.

The expression of the gene 2 sarcoplasmic/endoplasmic-reticulum Ca2(+)-pump isoforms (SERCA2a and SERCA2b) and of phospholamban was studied in pig smooth muscle of the stomach, longitudinal ileum, pulmonary artery and aorta. mRNA levels were determined using an RNAase protection assay. The SERCA2 isoforms and phospholamban were tested on Western blots with a panel of antibodies, some of which were isoform-specific. The pig smooth-muscle tissues all contained comparable SERCA2 mRNA levels, but these levels were 10-20-fold lower than SERCA2 mRNA levels in cardiac muscle. Of the SERCA2 mRNAs in smooth muscle, 72-81% encoded the non-muscle isoform (SERCA2b), and Western blot analysis with isoform-specific antibodies confirmed that the SERCA2b isoform is the predominant endoplasmic-reticulum Ca2(+)-pump in smooth muscle. In contrast with SERCA2 mRNA levels, phospholamban mRNA levels varied by 12-fold between the different pig smooth-muscle tissues, with low and very low levels in the pig pulmonary artery and the pig aorta respectively. The differential expression of phospholamban was also confirmed on Western blots. The finding that the phospholamban content varied between the different smooth-muscle tissues whereas the SERCA2 expression remained rather constant indicates that, in pig smooth muscle, the expression of phospholamban is not coupled with that of SERCA2.

Animals↗

PubMed1989

Smooth muscle expresses a cardiac/slow muscle isoform of the Ca2+-transport ATPase in its endoplasmic reticulum.

Smooth muscle expresses in its endoplasmic reticulum an isoform of the Ca2+-transport ATPase that is very similar to or identical with that of the cardiac-muscle/slow-twitch skeletal-muscle form. However, this enzyme differs from that found in fast-twitch skeletal muscle. This conclusion is based on two independent sets of observations, namely immunological observations and phosphorylation experiments. Immunoblot experiments show that two different antibody preparations against the Ca2+-transport ATPase of cardiac-muscle sarcoplasmic reticulum also recognize the endoplasmic-reticulum/sarcoplasmic-reticulum enzyme of the smooth muscle and the slow-twitch skeletal muscle whereas they bind very weakly or not at all to the sarcoplasmic-reticulum Ca2+-transport ATPase of the fast-twitch skeletal muscle. Conversely antibodies directed against the fast-twitch skeletal-muscle isoform of the sarcoplasmic-reticulum Ca2+-transport ATPase do not bind to the cardiac-muscle, smooth-muscle or slow-twitch skeletal-muscle enzymes. The phosphorylated tryptic fragments A and A1 of the sarcoplasmic-reticulum Ca2+-transport ATPases have the same apparent Mr values in cardiac muscle, slow-twitch skeletal muscle and smooth muscle, whereas the corresponding fragments in fast-twitch skeletal muscle have lower apparent Mr values. This analytical procedure is a new and easy technique for discrimination between the isoforms of endoplasmic-reticulum/sarcoplasmic-reticulum Ca2+-transport ATPases.

Animals↗

PubMed1989

Cloning and sequencing of the fbcF, B and C genes encoding the cytochrome b/c1 complex from Rhodopseudomonas viridis.

The complete nucleotide sequence of the genes encoding the Rieske FeS, the cytochrome b and the cytochrome c1 subunits of the ubiquinol-cytochrome c2 oxidoreductase from the photosynthetic purple bacterium Rhodopseudomonas viridis, and the derived amino acid sequences are presented. These three genes, fbcF, fbcB and fbcC, are located at contiguous sites of the genome. The DNA-deduced amino acid sequences are compared with known primary structures of corresponding proteins from other purple photosynthetic bacteria, as well as mitochondria, cyanobacteria and chloroplasts.

Amino Acid Sequence↗