Ultrasound guided puncture of the brachial artery for haemodialysis fistula angiography.
(41/550)
BACKGROUND: Arterio-venous (a-v) fistulae of haemodialysis patients frequently require function assessment by angiography. The purpose of the present study was to determine the efficacy and safety of ultrasound-guided transbrachial catheterization when a-v fistulae were evaluated. METHODS: Between July 1996 and December 1997, 208 dialysis patients, whose a-v fistulae (arterial inflow < 50 ml/min or venous pressure > 150 mm Hg in three consecutive HD sessions) were at the wrist or elbow, underwent transbrachial angiography using an ultrasound-guided 20-gauge IA needle to evaluate fistula function. Procedure-related symptoms or complications were noted in 28 patients and these were analysed. RESULTS: No apparent cases of vessel spasm or thrombosis were noted. Reported symptoms in 28 patients (13.5%) included local arm pain (3.3%), transient paresthesia (0.9%), mild ecchymosis (10.6%) and haematoma (0.9%). All complications were minor and none required surgical intervention. CONCLUSION: Ultrasound-guided puncture of the brachial artery is a safe, reliable and effective procedure in skilled hands and should be the preferred means of catheterization whenever haemodialysis angiography is performed. (+info)
Evaluation of thrombolysis in a porcine model of chronic deep venous thrombosis: an endovascular model.
(42/550)
PURPOSE: The advancement of catheter-based interventions for vascular recanalization has underscored the need for an experimental animal model of vascular thrombosis that can be used for the evaluation of interventional therapies. In this model, a porcine model of deep venous thrombosis with a novel endovascular technique was described, and the efficacy of thrombolytic therapy with urokinase was evaluated. METHODS: An endovascular device that consisted of a tapered polytetrafluoroethylene graft attached within a self-expanding nitinol stent was delivered to bilateral common iliac veins in 20 pigs. Venous thrombosis occurred as a result of flow stasis created by the intrastent stenosis. Catheter-directed pulse-spray thrombolysis with urokinase (250,000 units) and heparin (5000 IU) was performed on one limb while the contralateral limb received control saline solution. Thrombolysis was performed in 1 hour (n = 4), 8 hours (n = 4), 3 days (n = 4), 7 days (n = 4), and 14 days (n = 4) after the stent-graft deployment. Venography and intravascular ultrasound were used to evaluate the efficacy of thrombolysis. Light microscopy was used for histologic analysis of the thrombus. RESULTS: Complete thrombolysis was achieved in groups with deep vein thrombosis that were younger than 1 day. Angioplasty of the tapered stent-grafts in the completely thrombolysed iliac vein was successful in restoring venous flow. The efficacy of thrombolysis in 3-day, 7-day, and 14-day groups was 86% +/- 7%, 73% +/- 13%, and 42% +/- 23%, respectively. The thrombolytic efficacy was enhanced to 92% +/- 16% and 86% +/- 18% (P <.05) in 3-day and 7-day groups, respectively, when doses of the pulse-spray thrombolysis were doubled. Increased dosages of the thrombolytic agent, however, did not significantly enhance the thrombus dissolution in the 14-day group. CONCLUSION: The thrombolytic efficacy of urokinase correlated with the chronicity of deep venous thrombosis in our model. An increased dose of urokinase may be used to enhance the efficacy of thrombolysis in a 1-week-old thrombus. (+info)
Ultrasound guided percutaneous thrombin injection of iatrogenic femoral artery pseudoaneurysms after coronary angiography and intervention.
(43/550)
Ultrasound guided percutaneous thrombin injection has recently been described for the treatment of iatrogenic femoral pseudoaneurysms. Patient selection and technical aspects of this technique are still evolving and safety data, particularly after coronary intervention, remains limited. The percutaneous thrombin injection of femoral artery pseudoaneurysms in 13 consecutive patients, most of whom were receiving antiplatelet/anticoagulant treatment (aspirin 11, heparin 4, clopidogrel 6), is reported. Thrombin (1000 U/ml) was injected over several seconds until Doppler colour flow within the cavity ceased. The median dose of thrombin injected was 800 U (range 200-1000 U) and the treatment was successful in all cases without complication. In one case, thrombus was visualised within the arterial lumen immediately after thrombin injection, but this dissolved spontaneously within five minutes without evidence of embolisation. In contrast to ultrasound guided compression, percutaneous thrombin injection of femoral pseudoaneurysms is a rapid, well tolerated, and successful technique even in patients receiving antiplatelet/anticoagulant treatment. (+info)
Daily catheter-directed single dosing of t-PA in treatment of acute deep venous thrombosis of the lower extremity.
(44/550)
The strong fibrin affinity of recombinant tissue plasminogen activator (rt-PA) theoretically obviates continuous infusion or replacement of t-PA after direct intrathrombic injection. This hypothesis led the authors to evaluate single daily catheter-directed injection of rt-PA as a thrombolytic treatment for acute deep vein thrombosis of the lower extremity. Once-daily injection of rt-PA was performed in large thrombosed veins (popliteal or larger) with use of pulse-spray catheters and in small thrombosed veins in patients' calves with use of 3-4-F coaxial catheters. Patients received only full systemic anticoagulation on his/her patient care unit. This dosing regimen has been tested in 10 patients (12 legs) with a maximum dose of 50 mg per leg per day. Extensive thrombolysis was achieved in nine patients and partial thrombolysis was achieved in one patient, at an average total dose of 106 mg of rt-PA per leg. Minor bleeding was seen in three patients and no transfusions were needed. Our technique and the rationale for this pilot study is the focus of this article. (+info)
Permanent pacemaker implantation via the femoral vein: an alternative in cases with contraindications to the pectoral approach.
(45/550)
BACKGROUND: This paper presents a consecutive series of permanent pacemakers (PPM) implanted via the femoral vein in patients with contraindications to pacing systems via the superior vena cava (SCV). The femoral vein approach is a less invasive and feasible alternative to epicardial lead placement. METHODS: Twenty-seven patients had femoral pacemakers inserted. Indications for femoral vein pacemaker insertion were: SVC/subclavian obstruction (12 patients, 44.4%), previous infection in SVC leads (four patients, 14.8%), mastectomy and/or radiotherapy to chest (four patients, 14.8%), multiple leads in SVC (two patients, 7.4%), recurrent erosion (two patients, 7.4%), abnormal anatomy (one patient, 3.7%), painful pacemaker pocket (one patient, 3.7%) and burns (one patient, 3.7%). Fifty-one leads, 25 atrial and 26 ventricular, were inserted. The majority of leads were active fixations (96% of atrial leads and 85% ventricular leads). RESULTS: During a mean follow-up of 36.5 months (range 0.9-116.5), six additional unplanned procedures were performed in four patients. Atrial lead displacement occurred in five leads (20%). There were no ventricular lead displacements. In two patients, box revision for pre-erosion was required. One patient had persistent pain at the site of abdominal pacemaker generator. Infection, thromboembolic events, thromophlebitis, evidence of lower limb venous occlusion and lead fracture did not occur. CONCLUSION: Femoral vein PPM are a simple and feasible alternative in patients in whom the SVC approach is contraindicated. (+info)
Adverse events with transvenous left ventricular pacing in patients with severe heart failure: early experience from a single centre.
(46/550)
AIMS: Assessment of complications following implantation of transvenous ventricular electrodes to pace the left ventricle. METHODS AND RESULTS: Twenty-eight patients with severe cardiac failure and left bundle branch block were prospectively followed for adverse effects of implantation of a left ventricular transvenous pacing system. Immediate follow-up was associated with loss of left ventricular pacing in nine patients (32%). This was due to lead dislodgement in four cases (corrected by re-operation in three of these cases), and due to increased threshold in five cases (corrected by programming a higher pacing amplitude in all five cases, but with intermittent diaphragmatic contraction in one case). After 1 month, one patient died, one patient with severe coronary heart disease suffered a myocardial infarction, and left ventricular pacing was lost in two patients. Pericardial effusion, new significant ventricular arrhythmias or other adverse effects were not observed. After a mean follow-up of 16 +/- 9.2 months, pacing leads remained stable and no late complications related to the transvenous left ventricular epicardial pacing were observed. CONCLUSION: Placement of a permanent lead in a tributary of the coronary sinus is feasible without serious adverse effects during the first month. The only frequent adverse event was lead dislodgement; a finding which emphasizes the need for development of specially designed leads for this application. (+info)
Transradial approach for diagnostic selective cerebral angiography: results of a consecutive series of 166 cases.
(47/550)
BACKGROUND AND PURPOSE: Diagnostic selective cerebral angiography is commonly performed via transfemoral and transbrachial approaches. With these approaches, however, patients occasionally suffer serious complications. The purpose of this study was to evaluate the feasibility, efficacy, and safety of a transradial approach as an alternative to the transfemoral and transbrachial approaches. METHODS: Between October 1998 and September 1999, transradial cerebral angiography was performed in 166 consecutive patients in a single center as a diagnostic procedure. Before the procedure, we confirmed the collateral blood supply to the hand from the ulnar artery using a modified Allen test. Regular catheterization techniques were practiced using our newly designed 120-cm-long 4F catheter. In 42 patients, anticoagulant and/or antiplatelet therapy was given perioperatively. RESULTS: Twelve of the 166 patients proved to be poor candidates for the transradial approach, owing to restlessness (n = 9), lack of collateral blood supply via the ulnar artery (n = 2), and brachial artery stenosis (n = 1). The radial artery was successfully punctured and cannulated in the remaining 154 patients. Selective catheterization of the intended vessels was obtained in all carotid and vertebral angiographic procedures with no major vascular complications. CONCLUSION: Compared with transfemoral and transbrachial approaches, the transradial approach is a less invasive and safer technique for selective cerebral angiography and may warrant consideration as a standard procedure. Anticoagulant or antiplatelet therapy need not be discontinued for this method. (+info)
Endovascular access to the meningohypophyseal trunk.
(48/550)
SUMMARY: We describe a novel technique to selectively catheterize the meningohypophyseal trunk (MHT) and its branches. We emphasize the difficulty in accessing the MHT via an ipsilateral approach because of the geometric orientation of this vessel to the parent internal carotid artery. (+info)