JOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue S1 2004
DT Crowe
A technique for placement of a long-term arterial catheter that the author developed was used in 20 canine patients. The catheter was used for pressure monitoring and arterial blood sampling. The technique involved the following steps post-sedation and placement of a local anesthetic: 1Clipping and prepping of the medial aspect of the distal tibia and proximal metatarsal region; 2Incision over the medial tibial malleolus just caudal to the cranial tibial muscle-tendon; 3Blunt dissection of the space just caudal to the cranial tibialis tendon; 4Isolation of the cranial tibial artery and loop placement proximally and distally; 5Placement of a 3 Fr. polyurethane 4,8 cm catheter using a Seldinger wire technique; 6Placement of a suture in the periosteium of the distal tibia and anchoring of the catheter with this suture; 7Closure of the skin incision with sutures or staples; 8Bandage application to hold the catheter in place. The entire surgical procedure was done using sterile technique. The catheter was able to be kept in place and working for up to 9 days (averaged 4 days). This compared favorably retrospectively over dorsalis pedis catheters that lasted only a maximum of 4 days. (average 1.5 days). Because of the size of the catheter (3 Fr.) it provided improved waveforms over that observed with the dorsalis pedis catheter (22 g) and its occlusion rate was very low (2 in 20). The cranial tibial artery catheter was found to be particularly effective because the catheter was able to be inserted several cm up the artery and the catheter was able to be anchored well. No major complications were observed with this technique. Because of its effectiveness it is recommended to be used routinely over femoral artery and dorsal pedis artery catheters. [source]

PREVENTION OF TUNNELED HAEMODIALYSIS CATHETER (TC) RELATED INFECTIONS USING CATHETER RESTRICTED FILLING WITH GENTAMICIN AND CITRATE

NEPHROLOGY, Issue 1 2002
G Dogra
[source]

TRACING THE ORIGIN OF MULTI-DRUG RESISTANT (MDR) ESCHERICHIA COLI INFECTIONS FROM URINARY CATHETERS IN ICU CANINE PATIENTS

JOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue S1 2004
J Ogeer-Gyles
Introduction: Urinary tract infections (UTIs) in dogs with urinary catheters in intensive care units (ICUs) are frequent. Historically, multi-drug resistant (MDR) Escherichia coli account for about 10% of the UTIs. The objectives of this study were to determine the frequency of E. coli infections and of MDR E. coli in dogs with UTIs in our ICU, and to assess whether the MDR E. coli were community-acquired or nosocomial in origin. Methods: Over a 1-year period, rectal swabs were taken from all dogs in the ICU on the day of admission (D0) and on days 3 (D3), 6 (D6), 9 (D9) and 12 (D12). Urine was collected on these days from dogs with an indwelling urinary catheter (n=190). Rectal swabs and urine were routinely cultured. E. coli isolates were identified by biochemical tests. Using NCCLS guidelines, antibiotic susceptibility testing was done by disk diffusion method on fecal and urinary E. coli isolates. Twelve antimicrobial agents were used: nalidixic acid, enrofloxacin, cephalothin, cefoxitin, cefotaxime, ceftiofur, trimethoprim-sulfa, chloramphenicol, gentamicin, tetracycline, ampicillin, and amoxicillin/clavulanate. Pulsed-field gel electrophoresis (PFGE) was used to compare MDR E. coli UTI strains with fecal E. coli strains from the same patient and with MDR fecal E. coli from patients that were adjacent to, or housed in the same cages. Results: E. coli was cultured from 12 (48%) of 25 UTIs. Two of the E. coli were MDR. For one dog, PFGE showed no similarities among fecal E. coli and the urinary MDR E. coli isolates from the patient or between these isolates and fecal E. coli from a dog housed in the same kennel on the previous day. The MDR E. coli UTI was likely acquired prior to admission to the ICU, as it was present on D0. For the other dog, PFGE showed genetic similarity but not complete identity between the D3 MDR E. coli urinary isolate and the D3, D6, D9 fecal MDR isolates. This suggests that the UTI originated with the fecal E. coli. Using selective plates, fecal MDR E. coli were not found on D0. Selection of the MDR strain in the intestine by the use of antibiotics occurred while the dog was in the ICU and possibly led to the UTI. Conclusions: Multi-drug resistant E. coli accounted for 2 of 12 E. coli UTIs in dogs in the ICU over a 1-year period. Genotyping showed that one of the two MDR E. coli infections could possibly be of nosocomial origin. [source]

Catheter-Assisted Vein Sclerotherapy: A New Approach for Sclerotherapy of the Greater Saphenous Vein with a Double-Lumen Balloon Catheter

DERMATOLOGIC SURGERY, Issue 4 2007
JENS P. BRODERSEN MD
OBJECTIVE We sought to optimize sclerotherapy of the greater saphenous vein (GSV) by targeted application of foamed sclerosant by using a catheter. METHODS We designed a new double-lumen catheter that is inserted into the GSV. Via one lumen, a balloon at the tip of the catheter can be inflated to stop the blood flow. Via the second lumen, the sclerosing agent can be injected and aspirated. This method enabled us to perform a targeted application of the sclerosing agent [catheter-assisted vein sclerotherapy (KAVS)]. In an open study, outpatients suffering from varicosis of the GSV received a foam sclerotherapy under ultrasound guidance, using the newly developed KAVS catheter. RESULTS Thirty patients with an insufficiency (reflux) of the GSV were treated with the newly developed KAVS method using foamed polidocanol. The intervention was well tolerated in all patients without the occurrence of serious side effects. In 27 of the 30 treated patients (90%), we found a closure of the GSV at control visits 6 weeks, 3 months, and 6 months after treatment. CONCLUSIONS The KAVS method represents a feasible approach for sclerotherapy of the GSV. The efficiency and treatment modalities need to be explored in further studies. [source]

Role of the Peripheral Intravenous Catheter in False-positive D-dimer Testing

ACADEMIC EMERGENCY MEDICINE, Issue 2 2001
Alan C. Heffner MD
Abstract. Objective: To determine whether inserting a peripheral intravenous catheter (IV) can significantly increase the circulating D-dimer concentration. Methods: Twenty healthy young adult volunteers underwent cannulation of an antecubital vein with a 20-gauge Teflon IV. Time 0 venous blood was drawn during IV insertion. The IV was salinelocked and left in place for 90 minutes, at which time a second venipuncture was performed in a contralateral antecubital vein (+90 min). A qualitative D-dimer assay [erythrocyte-agglutination assay, SimpliRED (SRDD)] and a quantitative spectrophotometric assay [enzyme-linked immunosorbent assay (EIA), Dimertest Gold] were performed on all samples. Time 0 means (±SD) were compared with +90 min means by paired t-test, and SRDD pairs were compared with McNemar's test. Results: Time 0 initial venipuncture blood samples yielded a mean D-dimer concentration of 15 ± 24 ng/mL, with 2/20 SRDD tests read as positive (95% CI = 1% to 32%). At +90 min, the D-dimer concentration was 33 ± 21 ng/mL (p = 0.04 vs time 0), with 5/20 SRDD tests read as positive (95% CI = 9% to 49%, p = 0.248). Conclusions: Insertion of an IV increased the circulating D-dimer concentration (determined by EIA), but did not lead to a significant increase in false-positive conversion of the SRDD. An effort should be made to perform D-dimer testing on "first-stick" blood to optimize specificity. However, a strongly positive D-dimer reaction cannot be ascribed to the presence of an IV. [source]

Closure of Adult Patent Ductus Arteriosus Under Cardiopulmonary Bypass by Using Foley Balloon Catheter

JOURNAL OF CARDIAC SURGERY, Issue 3 2007
Yildirim Tekin M.D.
Method: We present a 43-year-old female patient who underwent successful ductal closure operation under cardiopulmonary bypass (CPB) via a transpulmonary route. Results: The operation was uneventful and the patient was discharged from the hospital on the 4th postoperative day. Conclusion: Transpulmonary route for the closure of the PDA by using CPB is a safe and acceptable approach in adult patients. [source]

The Permanency of Pulmonary Vein Isolation Using a Balloon Cryoablation Catheter

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2010
HUMERA AHMED B.A.
Chronic PV Isolation With the Cryoballoon.,Background: Because of its technical feasibility and presumed safety benefits, balloon cryoablation is being increasingly employed for pulmonary vein (PV) isolation. While acute isolation has been demonstrated in most patients, little data are available on the chronic durability of cryoballoon lesions. Methods and Results: Twelve atrial fibrillation patients underwent PV isolation using either a 23-mm or 28-mm cryoballoon. For each vein, after electrical isolation was verified with the use of a circular mapping cathether, 2 bonus balloon ablation lesions were placed. Gaps in balloon occlusion were overcome using either a spot cryocatheter or a "pull-down" technique. A prespecified second procedure was performed at 8,12 weeks to assess for long-term PV isolation. Acute PV isolation was achieved in all PVs in the patient cohort (n = 48 PVs), using the cryoballoon alone in 47/48 PVs (98%); a "pull-down" technique was employed for 5 PVs (1 right superior pulmonary vein, 2 right inferior pulmonary veins, and 2 left inferior pulmonary veins). The gap in the remaining vein was ablated with a spot cryocatheter. During the second mapping procedure, 42 of 48 PVs (88%) remained isolated. One vein had reconnected in 2 patients, while 2 veins had reconnected in another 2 patients. All PVs initially isolated with the "pull-down" technique remained isolated at the second procedure. Conclusions: Cryoballoon ablation allows for durable PV isolation with the use of a single balloon. With maintained chronic isolation in most PVs, it may represent a significant step toward consistent and lasting ablation procedures. (J Cardiovasc Electrophysiol, Vol. pp. 731-737, July 2010) [source]

Age-Related Increase in Atrial Fibrillation Induced by Transvenous Catheter-Based Atrial Burst Pacing: An In Vivo Rat Model of Inducible Atrial Fibrillation

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2010
DONGZHU XU M.D.
AF Rat Model Induced by Transvenous Catheter Pacing.,Introduction: Large animal models of atrial fibrillation (AF) are well established, but limited experimental reports exist on small animal models. We sought to develop an in vivo rat model of AF using a transvenous catheter and to evaluate the model's underlying characteristics. Methods and Results: Echocardiogram, surface electrocardiogram (ECG), and atrial effective refractory period (AERP) were recorded at baseline in young (3 months) and middle-aged (9 months) Wistar rats. AF inducibility and duration were measured through transvenous electrode catheter in young (n = 11) and middle-aged rats (n = 11) and middle-aged rats treated with either pilsicainide (1 mg/kg iv, n = 7) or amiodarone (10 mg/kg iv, n = 9). Degrees of interstitial fibrosis and cellular hypertrophy in the atria were assessed histologically. The P-wave duration and AERP were significantly longer and echocardiographic left atrial dimension significantly larger in middle-aged versus young rats. AF was inducible in >90% of all procedures in both untreated rat groups, whereas AF inducibility was reduced by the antiarrhythmic drugs. The AF duration was significantly longer in middle-aged than in young rats and was significantly shortened by treatment with either pilsicainide or amiodarone. Histologic analysis revealed significant increases in atrial interstitial fibrosis and cellular diameter in middle-aged versus young rats. Conclusions: Transvenous catheter-based AF is significantly longer in middle-aged than in young rats and is markedly reduced by treatment with antiarrhythmic drugs. This rat model of AF is simple, reproducible, and reliable for examining pharmacologic effects on AF and studying the process of atrial remodeling.(J Cardiovasc Electrophysiol, Vol. 21, pp. 88,93, January 2010) [source]

First Experiences for Pulmonary Vein Isolation with the High-Density Mesh Ablator (HDMA): A Novel Mesh Electrode Catheter for Both Mapping and Radiofrequency Delivery in a Single Unit

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2009
AXEL MEISSNER M.D.
Background: Interventional therapy of atrial fibrillation (AF) is often associated with long examination and fluoroscopy times. The use of mapping catheters in addition to the ablation catheter requires multiple transseptal sheaths for left atrial access. Objectives: The purpose of this prospective study was to evaluate feasibility and safety of pulmonary vein (PV) isolation using the high-density mesh ablator (HDMA), a novel single, expandable electrode catheter for both mapping and radiofrequency (RF) delivery at the left atrium/PV junctions. Methods: Twenty-six patients with highly symptomatic paroxysmal AF (14, 53.8%) and persistent AF (12, 46.2%) were studied. Segmental PV isolation via the HDMA was performed using a customized pulsed RF energy delivery program (target temperature 55,60°C, power 70,100 W, 600,900 seconds RF application time/PV). Results: All 104 PVs in 26 patients could be ablated by the HDMA. Segmental PV isolation was achieved with a mean of 3.25 ± 1.4 RF applications for a mean of 603 ± 185 seconds. Entrance conduction block was obtained in 94.2% of all PV. The mean total procedure and fluoroscopy time was 159.0 ± 32 minutes and 33.5 ± 8.6 minutes, respectively. None of the patients experienced severe acute complications. After 3 months no PV stenosis was observed, and 85.6% and 41.6% of the patients with PAF and persistent AF, respectively, did not report symptomatic AF. Conclusions: In this first study of PV isolation using the HDMA, our findings suggest that this method is safe and yields good primary success rates. The HDMA simplifies AF ablation, favorably impacting procedure and fluoroscopy times. [source]

Clinical Experience with a Single Catheter for Mapping and Ablation of Pulmonary Vein Ostium

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2009
PAOLO DE FILIPPO M.D.
Introduction: The aim of this single center study is to evaluate the safety and the efficacy of performing pulmonary vein isolation (PVI) using a single high-density mesh ablator (HDMA) catheter. Methods: A total of 17 consecutive patients with paroxysmal (10 patients) or persistent atrial fibrillation (7 patients) and no heart disease were enrolled. A single transseptal puncture was performed and the HDMA was placed at each PV ostium identified with anatomic and electrophysiological mapping. Pulsed radiofrequency (RF) energy was delivered at the targeted temperature of 58°C with maximum power of 80 watts. No other ablation system was utilized. The primary objective of the study was acute isolation of the targeted PV, and the secondary objective was clinical efficacy and safety of PVI with HDMA for atrial fibrillation (AF) prevention. Patients were followed at intervals of 1, 3, 6, and 12 months. Results: PVI was attempted with HDMA in 67/67 PVs. [Correction made after online publication October 27, 2008: PVs changed from 6/67 to 67/67] Acute success rate were: 100% (16/16) for left superior PV, 100% (16/16) for left inferior PV, 100% (17/17) for right superior PV, 100% (1/1) for left common trunk and 47% (8/17) for right inferior PV. Total procedure time was 200 ± 36 minutes (range 130,240 minutes) and total fluoroscopy time was 42 ± 18 minutes (range 23,75 minutes). During a mean follow-up of 11 ± 4 months, 64% of patients remained in sinus rhythm (8/10 paroxysmal AF and 3/7 for persistent AF). No complications occurred either acutely or at follow-up. Conclusions: PV isolation with HDMA is feasible and safe. The midterm efficacy in maintaining sinus rhythm is higher in paroxysmal than in persistent patients. [source]

Comparison of Cool Tip Versus 8-mm Tip Catheter in Achieving Electrical Isolation of Pulmonary Veins for Long-Term Control of Atrial Fibrillation: A Prospective Randomized Pilot Study

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2006
SANJAY DIXIT M.D.
Objective: To compare safety and efficacy of 8-mm versus cooled tip catheter in achieving electrical isolation (EI) of pulmonary veins (PV) for long-term control of atrial fibrillation (AF). Background: There is paucity of studies comparing safety/efficacy of 8-mm and cooled tip catheters in patients undergoing AF ablation. Methods and Results: This was a randomized and patient-blinded study. Subjects were followed by clinic visits (at 6 weeks and 6 months) and transtelephonic monitoring (3-week duration) done around each visit. Primary endpoints were: (1) long-term AF control (complete freedom and/or >90% reduction in AF burden on or off antiarrhythmic drugs at 6 months after a single ablation), and (2) occurrence of serious adverse events (cardiac tamponade, stroke, LA-esophageal fistula, and/or death). Eighty-two patients (age 56 ± 9 years, 60 males, paroxysmal AF = 59) were randomized (42 patients to 8-mm tip and 40 patients to cooled tip). EI of PVs was achieved in shorter time by the 8-mm tip as compared with cooled tip catheter (40 ± 23 minutes vs 50 ± 30 minutes; P < 0.05) but long-term AF control was not different between the two (32 patients [78%] vs 28 patients [70%], respectively; P = NS). One serious adverse event occurred in each group (LA-esophageal fistula and stroke, respectively) and no significant PV stenosis was observed in either. Conclusion: EI of PVs using either 8-mm or cooled tip catheter results in long-term AF control in the majority after a single ablation procedure, with comparable efficacy and safety. [source]

Creating Continuous Linear Lesions in the Atria: A Comparison of the Multipolar Ablation Technique Versus the Conventional Drag-and-Burn

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2005
WILBER W. SU M.D.
Introduction: Catheter-based treatment of atrial fibrillation (AF) requires the isolation of the triggering foci as well as modification of the atria with substrate that sustains AF. The creation of linear lesions in the left atrium with standard radiofrequency ablative methods requires long procedural times with unpredictable results. Methods: The simultaneous delivery of phase-shifted radiofrequency energy from a multipolar catheter was compared to the conventional drag-and-burn technique for creating linear lesions in 10 dogs. Four atrial sites were targeted under intracardiac ultrasound and fluoroscopic guidance in each of 10 dogs. The conventional drag-and-burn technique or the multipolar phase-shifted ablation catheter was randomly applied for 60 seconds and compared. Results: Creating linear lesions using the simultaneous multipolar phase-shifted ablation catheter was on average 11.0 minutes faster (33.6 minutes vs 44.6 minutes, P < 0.01) than the drag-and-burn method. The fraction of the lesion length achieved using phase-shifted ablation compared to that intended was 23% greater (76% vs 53%, P < 0.01), and has less discontinuities (0.1 compared to 0.8 discontinuities/line, P < 0.003). There was no significant difference in either the lesion transmurality, or fluoroscopy times. Conclusion: The simultaneous delivery of phase-shifted, radiofrequency energy using a multipolar catheter is more effective and efficient in producing linear lesions than the traditional drag-and-burn technique. Using the multipolar ablative method to create linear lesions may be a useful technique in the treatment of patients with substrate-mediated atrial fibrillation. [source]

Usefulness of a New Radiofrequency Thermal Balloon Catheter for Pulmonary Vein Isolation:

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2003
A New Device for Treatment of Atrial Fibrillation
Introduction: A rapidly firing or triggered ectopic focus located within a pulmonary vein (PV) or close to the PV ostium could induce atrial fibrillation (AF). The aim of this study was to evaluate the efficacy and safety of a radiofrequency thermal balloon catheter for isolation of the PV from the left atrium (LA). Methods and Results: Twenty patients with drug-resistant paroxysmal AF were treated by isolating the superior PVs using an RF thermal balloon catheter. Using a transseptal approach, the balloon, which had an inflated diameter 5 to 10 mm larger than that of the PV ostium, was wedged at the LA-PV junction. It was heated by a very-high-frequency current (13.56 MHZ) applied to the coil electrode inside the balloon for 2 to 3 minutes, and the procedure was repeated up to four times. The balloon center temperature was maintained at 60° to 75°C by regulating generator output. Successful PV isolation was achieved in 19 of the 20 left superior PVs and in all 20 of the right superior PVs and was associated with a decrease in amplitude of the ostial potentials. Total procedure time was1.8 ± 0.5hours, which included22 ± 7minutes of fluoroscopy time. After a follow-up period of8.1 ± 0.8months, 17 patients were free from AF, with 10 not taking any antiarrhythmic drugs and 7 taking the same antiarrhythmic agent as before ablation. Electron beam computed tomography revealed no complications, such as PV stenosis at ablation sites. Conclusion: The PV and its ostial region can be safely and quickly isolated from the LA by circumferential ablation around the PV ostia using a radiofrequency thermal balloon catheter for treatment of AF. (J Cardiovasc Electrophysiol, Vol. 14, pp. 609-615, June 2003) [source]

Rapid Magnetic Electroanatomic Mapping of Typical Atrial Flutter Using a Novel Multielectrode Catheter

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2003
Vijay S. Chauhan M.D. F.R.C.P.C.
[source]

Clinical Usefulness of a Multielectrode Basket Catheter for Idiopathic Ventricular Tachycardia Originating from Right Ventricular Outflow Tract

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2001
TAKESHI AIBA M.D.
Basket Catheter in Idiopathic VT.Introduction: It often is difficult to determine the optimal ablation site for idiopathic ventricular tachycardia (VT) originating from the right ventricular outflow tract (RVOT) when the VT or premature ventricular complex (PVC) does not occur frequently. The aim of our study was to evaluate the usefulness of a multielectrode basket catheter for ablation of idiopathic VT originating from the RVOT. Methods and Results: Radiofrequency (RF) catheter ablation was performed using a 4-mm tip, quadripolar catheter in 50 consecutive patients with 81 VTs originating from the RVOT with (basket group = 25 patients with 45 VTs) or without (control group = 25 patients with 36 VTs) predeployment of a multielectrode basket catheter composed of 64 electrodes. Deployment of the multielectrode basket catheter was possible and safe in all 25 patients in the basket group. Ablation was successful in 25 (100%) of 25 patients in the basket group and in 22 (88%) of 25 patients in the control group. The total number of RF applications and the number of RF applications per PVC morphology did not differ between the two groups. However, both the fluoroscopic and ablation procedure times per PVC morphology were shorter in the basket group than in the control group (36.8 ± 14.1 min vs 52.0 ± 32.5 min, P = 0.04; 60.0 ± 14.6 vs 81.5 ± 51.2 min, P = 0.05). This difference was more pronounced in the 29 patients in whom VT or PVC was not frequently observed. Conclusion: The multielectrode basket catheter is safe and useful for determining the optimal ablation site in patients with idiopathic VT originating from the RVOT, especially in those without frequent VT or PVC. [source]

Clinical Experience with a Novel Intracoronary Perfusion Catheter to Treat No-Reflow Phenomenon in Acute Coronary Syndromes

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 2 2010
GABRIEL MALUENDA M.D.
Background:,The no-reflow phenomenon is an often seen complication in patients presenting with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). This event is associated with poor prognosis and poses a therapeutic challenge. Methods:,This retrospective study cohort was composed of 30 patients who presented with ACS between September 2007 and April 2009, and developed no-reflow during subsequent PCI. The primary end-point was defined as normal Thrombolysis In Myocardial Infarction (TIMI) 3 flow with myocardial blush grade (MBG) ,2 or an increase in TIMI flow by ,2 grades with a MBG ,2 after intracoronary drug infusion via the ClearWay (CW) RX perfusion catheter. Results:,The population presented with a relatively high prevalence of cardiovascular risk factors. ST-elevation myocardial infarction was the most common presentation (60.0%), while 20% of the patients presented with cardiogenic shock. After intracoronary infusion of nicardipine or nitroprusside using the CW catheter, TIMI flow improved from the baseline in 19 cases (63.3%, P < 0.001), and 16 patients (53.3%, P < 0.001) achieved normal coronary flow at the end of the procedure. The rate of in-hospital death was 6.7% (2 cases). No clinical differences were noted between those patients who successfully achieved normal coronary flow and those with persistent no-reflow. Conclusion:,The infusion of intracoronary drugs using the novel perfusion CW RX catheter seems to be safe and could help to improve myocardial perfusion in a selected group of patients presenting with ACS who developed no-reflow during PCI. (J Interven Cardiol 2010;23:109-113) [source]

Predictors of Complete Heart Block After Alcohol Septal Ablation for Hypertrophic Cardiomyopathy and the Timing of Pacemaker Implantation

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2007
F.R.A.C.P., SEIFEDDIN S. EL-JACK M.B.B.S.
Catheter-based alcohol septal ablation has recently been introduced for the treatment of left ventricular outflow tract obstruction in hypertrophic obstructive cardiomyopathy. It is associated with various conduction disturbances and may lead to transient or persistent complete heart block (CHB). Electrocardiographic (ECG) changes and predictors of developing CHB and the timing of permanent pacemaker implantation have been variable among the different studies. Among 50 patients studied, we found that a new right bundle branch pattern was the most common new ECG change after septal ablation and that baseline left bundle branch block was strongly associated with the development of CHB (P = 0.004); 9 patients (18%) required permanent pacemaker implantation of whom 7 (78%) remained pacemaker dependent at 14 days with no delayed recovery of atrioventricular conduction. This favors an early pacemaker implantation strategy. [source]

Transesophageal Echocardiography and Intracardiac Echocardiography Differently Predict Potential Technical Challenges or Failures of Interatrial Shunts Catheter-Based Closure

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2007
GIANLUCA RIGATELI M.D.
We sought to prospectively assess the role of transesophageal (TEE) and intracardiac echocardiography (ICE) in detecting potential technical difficulties or failures in patients submitted to interatrial shunts percutaneous closure. We prospectively enrolled 46 consecutive patients (mean age 35±28, 8 years, 30 female) referred to our center for catheter-based closure of interatrial shunts. All patients were screened with TEE before the intervention. Patients who met the inclusion criteria underwent ICE study before the closure attempt (40 patients). TEE detected potential technical difficulties in 22.5% (9/40) patients, whereas ICE detected technical difficulties in 32.5% (13/40 patients). In patients with positive TEE/ICE the procedural success (92.4% versus 100% and, P = ns) and follow-up failure rate (7.7% versus 0%, P = ns) were similar to patients with negative TEE/ICE, whereas the fluoroscopy time (7 ± 1.2 versus 5 ± 0.7 minutes, P < 0.03), the procedural time (41 ± 4.1 versus 30 ± 8.2 minutes, P ± 0.03), and technical difficulties rate (23.1% versus 0%, P = 0.013) were higher. Differences between ICE and TEE in the evaluation of rims, measurement of ASD or fossa ovalis, and detection of venous valve and embryonic septal membrane remnants impacted on technical challenges and on procedural and flouroscopy times but did not influence the success rate and follow-up failure rate. [source]

Percutaneous Retrieval of a Broken Catheter from the Left Atrium in an Adult

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2002
ANGELO BRUNO RAMONDO M.D.
We performed a percutaneous retrieval of a broken catheter from the left atrium in an adult patient using transseptal left heart catheterization and a helical basket guidewire. To our knowledge, this is the first description of such a therapeutical option for a foreign body lodged in the left atrium of an adult patient. [source]

Catheter-Based Transendocardial Myocardial Gene Transfer

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2002
CHRISTER SYLVÉNM.D. Ph.D.
Background and Aim: Local modulation of myocardial function by gene transfer or cell depositions constitutes a potential method of cardiac treatment. This study tested the morphology of myocardial plasmid gene transfer by catheter-based transendocardial injection (NOGA). Methods: Left ventricular morphology and electrical and mechanical characteristics were mapped in three dimensions. In two pigs, 0.10 mL oftoluidine blue was injected at ten sites. In seven pigs, seven to ten injections of 0.10 mL saline containing 0.10 mg pCMV-LacZ expressing the enzyme ,-galactosidase and 0.10 mg phVEGF-A165 were given. The pigs were sacrificed after 3 days and gene expression was determined. Results: Macroscopically on the endocardial surface, all identified spots were located in the target area. However, along the transmyocardial axis, injections with color and plasmid were located randomly throughout the left ventricular wall from the endocardium to the epicardium. In each detected spot, gene expression of ,-galactosidase was observed in an approximate myocardial volume of 5 × 5 × 5 mm. Microscopically, the transfected cells were located typically at the tip of the injection scar. As a rule, 10 to 20 transfected cells were located at the end of the injection scar. In sections where expression of both transcripts was observed, 42% of the cells expressed both ,-galactosidase and vascular endothelial growth factors (VEGF), 32% only ,-galactosidase, and 26% only VEGF. Conclusions: Myocardial gene transfer following magnetic guidance can be located precisely on the left ventricular inner surface. Within the myocardium, gene expression is local around the distal tip of the injection scar and is located randomly at every level of depth of the left ventricular wall. [source]

Catheter-Based Angiography in Patients with Cervical Internal Carotid Artery Occlusion: Is it Worth the Cost?

JOURNAL OF NEUROIMAGING, Issue 4 2008
M. Fareed K. Suri MD
No abstract is available for this article. [source]

Catheter Ablation for Paroxysmal Atrial Fibrillation: A Randomized Comparison between Multielectrode Catheter and Point-by-Point Ablation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2010
ALAN BULAVA M.D., Ph.D.
Introduction:,Catheter ablation for paroxysmal atrial fibrillation is widely used for patients with drug-refractory paroxysms of arrhythmia. Recently, novel technologies have been introduced to the market that aim to simplify and shorten the procedure. Aim:,To compare the clinical outcome of pulmonary vein (PV) isolation using a multipolar circular ablation catheter (PVAC group), with point-by-point PV isolation using an irrigated-tip ablation catheter and the CARTO mapping system (CARTO group; CARTO, Biosense Webster, Diamond Bar, CA, USA). Methods:,Patients with documented PAF were randomized to undergo PV isolation using PVAC or CARTO. Atrial fibrillation (AF) recurrences were documented by serial 7-day Holter monitoring. Results:,One hundred and two patients (mean age 58 ± 11 years, 68 men) were included in the study. The patients had comparable baseline clinical characteristics, including left atrial dimensions and left ventricular ejection fraction, in both study arms (PVAC: n = 51 and CARTO: n = 51). Total procedural and fluoroscopic times were significantly shorter in the PVAC group (107 ± 31 minutes vs 208 ± 46 minutes, P < 0.0001 and 16 ± 5 minutes vs 28 ± 8 minutes, P < 0.0001, respectively). The AF recurrence was documented in 23% and 29% of patients in the PVAC and CARTO groups, respectively (P = 0.8), during the mean follow-up of 200 ± 13 days. No serious complications were noted in both study groups. Conclusions:,Clinical success rates of PV isolation are similar when using multipolar circular PV ablation catheter and point-by-point ablation with a three-dimensional (3D) navigation system in patients with PAF, and results in shorter procedural and fluoroscopic times with a comparable safety profile. (PACE 2010; 33:1039,1046) [source]

Comparison of fibrescope guided intubation via the classic laryngeal mask airway and i-gel in a manikin,

ANAESTHESIA, Issue 1 2010
L. De Lloyd
Summary We compared the classic laryngeal mask airway and i-gel as adjuncts to fibrescope guided intubation in a manikin. Two methods of intubation were compared with each device: the tracheal tube directly over the fibrescope; and the tracheal tube over an Aintree Intubation Catheter. Thirty-two anaesthetists took part in this randomised crossover study. Each anaesthetist performed two intubations with each method via each device. The mean (SD) time for the first intubation using the tracheal tube over the fibrescope was 43 (24) s with the classic laryngeal mask airway and 22 (9) s with the i-gel (95% CI for the difference 12,30 s, p < 0.0001). The mean (SD) times for the first intubation when using the Aintree Intubation Catheter was 46 (24) s with the classic laryngeal mask airway and 37 (9) s with the i-gel (95% CI for the difference 5,12 s, p < 0.0001). We recorded five (5/64, 8%) oesophageal intubations when using the classic laryngeal mask airway and none when using the i-gel. The participants rated the ease of railroading of the tracheal tube and railroading the Aintree Intubation Catheter over the fibrescope to be significantly easier (p < 0.0001 and p = 0.002 respectively) when using the i-gel than when using the classic laryngeal mask airway. Furthermore, 30/32 (94%) of anaesthetists reported preference for the i-gel over the classic laryngeal mask airway for fibrescope guided tracheal intubation when managing a difficult airway. We conclude that the i-gel is likely to be a more appropriate conduit than the classic laryngeal mask airway for fibrescope guided intubation irrespective of the intubation method used. [source]

Outpatient Management of Primary Spontaneous Pneumothorax in the Emergency Department of a Community Hospital Using a Small-bore Catheter and a Heimlich Valve

ACADEMIC EMERGENCY MEDICINE, Issue 6 2009
Behzad Hassani
Abstract Objectives:, The objective was to assess the effectiveness of a small-bore catheter (8F) connected to a one-way Heimlich valve in the emergency department (ED)-based outpatient management of primary spontaneous pneumothorax (PSP). Methods:, The authors conducted a structured chart audit in a retrospective case series of patients with PSP who were treated with a small-bore (8F) catheter and a Heimlich valve who were seen in the ED of a community hospital between April 2000 and March 2005. To be eligible, patients had to be available for a telephone interview. Main outcomes were success of treatment (sustained, complete lung reexpansion), admission, and surgical intervention rates. Secondary outcomes included number of chest x-rays (CXRs), number of visits to the ED, treatment duration, complications, and recurrence rates. Results:, The authors identified 62 discrete episodes of PSP in 50 patients, with a mean (±standard deviation [SD]) age of 25.5 ± 10.5 years (range = 14,53 years). In 50 of 62 episodes (81%, 95% confidence interval [CI] = 70.8% to 90.5%), patients were discharged directly from the ED. Patients were admitted to the hospital at some point for treatment in 27/62 episodes (43.5%, 95% CI = 31.2% to 55.9%). Surgery was performed for acute treatment failure in 17 episodes. Ultimately, 19 patients, who accounted for 21 of 62 episodes (33.9%, 95% CI = 22.1% to 45.6%), had surgery at some point in the study. Mean (±SD) time to admission for those patients initially discharged from the ED was 2.9 (±2.01) days (95% CI = 1.9 to 3.8 days). There were no serious complications from treatment; the minor complication rate (misplacement or dislodging of the chest tube) was 22.6% (95% CI = 12.2% to 33.0%). No association was found between the size of pneumothorax and treatment failure. Conclusions:, This study suggests that the initial management of PSP with a small-bore catheter and Heimlich valve can easily be performed by emergency physicians in the community hospital setting and appears safe. A larger study systematically comparing this approach with alternative therapies is needed. [source]

Flow Visualization Study of a Novel Respiratory Assist Catheter

ARTIFICIAL ORGANS, Issue 6 2009
Stephanus G. Budilarto
Abstract Respiratory assist using intravenous catheters may be a potential therapy for patients with acute and acute-on-chronic lung failure. An important design constraint is respiratory catheter size, and new strategies are needed that enable size reduction while maintaining adequate gas exchange. Our group is currently developing a percutaneous respiratory assist catheter (PRAC) that uses a rotating bundle of hollow fiber membranes to enhance CO2 removal and O2 supply with increasing bundle rotation rate. In this study, particle image velocimetry (PIV) was used to analyze the fluid flow patterns and velocity fields surrounding the rotating fiber bundle of the PRAC. The goal of the study was to assess the rotational flow patterns within the context of the gas exchange enhancement that occurs with increasing fiber bundle rotation. A PRAC prototype was placed in a 1-in. internal diameter test section of an in vitro flow loop designed specifically for PIV studies. The rotation rate of the PRAC was varied between 500 and 7000 rpm, and PIV was used to determine the velocity fields in the primary (r -,) and secondary (r - z) flow planes. The secondary flow exhibited time-varying and incoherent vortices that were consistent with the classical Taylor vortices expected for Taylor numbers (Ta) corresponding to the rotation speeds studied (2200 < Ta < 31 000). In the primary flow, the tangential velocity exhibited boundary layers of less than ½ mm adjacent to the fiber bundle and vessel wall. The estimated shear stress associated with the Taylor vortices was approximately 11 dyne/cm2 at 7000 rpm and was over 10 times smaller than the shear stress in the primary flow boundary layers. [source]

Blood Biocompatibility Assessment of an Intravenous Gas Exchange Device

ARTIFICIAL ORGANS, Issue 9 2006
Trevor A. Snyder
Abstract:, To treat acute lung failure, an intravenous membrane gas exchange device, the Hattler Catheter, is currently under development. Several methods were employed to evaluate the biocompatibility of the device during preclinical testing in bovines, and potential coatings for the fibers comprising the device were screened for their effectiveness in reducing thrombus deposition in vitro. Flow cytometric analysis demonstrated that the device had the capacity to activate platelets as evidenced by significant increases in circulating platelet microaggregates and activated platelets. Thrombus was observed on 20 ± 6% of the surface area of devices implanted for up to 53 h. Adding aspirin to the antithrombotic therapy permitted two devices to remain implanted up to 96 h with reduced platelet activation and only 3% of the surface covered with thrombus. The application of heparin-based coatings significantly reduced thrombus deposition in vitro. The results suggest that with the use of appropriate antithrombotic therapies and surface coatings the Hattler Catheter might successfully provide support for acute lung failure without thrombotic complications. [source]

Miniature Vibrating Flow Blood Pump Using a Cross-Slider Mechanism for External Shunt Catheter

ARTIFICIAL ORGANS, Issue 1 2003
S. Kawano
Abstract: The prototype of the miniature vibrating flow pump (VFP) is developed for the external shunt catheter. The cross-slider mechanism is applied to vibrate the tube, which causes the pumping effect. This mechanism results in successful development of the miniature and lightweight VFP. By the use of the prototype VFP, the experiment of the basic pump performance is made in detail based on the authorized procedure in the research field of fluids engineering. The typical H - Q curve of VFP, which is the relationship between the pump head and the flow rate, can be obtained. This result suggests that the miniature VFP developed here can be expected to be used as the booster pump for the external shunt catheter in clinical applications. [source]

Catheter-based closure of atrial septal defects in the oval fossa with the Amplatzer® device in patients in their first or second year of life,

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2009
G. Fischer MD
Abstract Objective: To assess feasibility, safety, and efficacy of the use of Amplatzer® occluders in closure of atrial septal defects (ASD) in children in the first 2 years of life. Background: Although scattered reports on such closure have been published, no agreement consists on the policy. Methods: In 654 patients of all ages, closure was achieved in 632 (96.6%). Data were analyzed retrospectively in all 71 children where an attempt had been made to close the ASD before their second birthday. Results: Median age and body weight were 17.2 months (range 3.9,23.8) and 10.0 kg (range 3.8,14.5), respectively. Median fluoroscopy time was 13.6 min and median device size 15 mm. Successful closure was achieved in 68 children (95.8%). Three times the procedure was aborted: in one, the device repeatedly straddled the septum; in the other two, a small left atrium restricted the movement of the left-sided disc. One device embolized and was reimplanted after retrieval. One infant with multiple disorders died 6 days after closure from acute sepsis probably unrelated to the procedure. No other complications occurred. Only trivial shunts closing with time were registered during follow-up. Symptomatic patients profited markedly from closure. Conclusion: The results and complications of ASD closure with the Amplatzer® device in patients in their first 2 years of life compare favorably with procedures in older patients, provided that the size of the septum and the dimensions in the left atrium are taken into consideration when selecting the size of the device. © 2009 Wiley-Liss, Inc. [source]

Catheter induced clot formation during angioplasty: An enoxaparin side effect?

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2007
Pedro A. Lemos MD
No abstract is available for this article. [source]

Prospective assessment of hemodialysis access patency after percutaneous intervention: Cox proportional hazards analysis

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005
John A. Bittl MD
Abstract Vascular access failure is the greatest limitation of successful hemodialysis, but the factors associated with long-term patency have not been fully elucidated. Outcomes in a consecutive series of 294 thrombosed or failing accesses [128 fistulas (43.5%) and 166 grafts (56.5%) in 179 patients] were analyzed with life table and multivariable Cox proportional hazards analysis. Initial success was achieved in 275 of 294 accesses (95.6%). The median patency after intervention was 206 days (interquartile range, 79,457 days). Fistulas had longer median patency after intervention than grafts (286 vs. 170 days). Nonthrombosed accesses had longer median patency than thrombosed accesses (238 vs. 136 days), but thrombosed fistulas had similar median patency as thrombosed grafts (140 vs. 136 days). The selective use of stents as a bailout for failed balloon dilatation did not significantly reduce long-term patency (196 days for stented accesses vs. 210 days for unstented accesses). Long-term patency was inversely related to final access pressure, but access patency was not related to the presence of central venous occlusions, graft age, patient age, sex, or diabetes. Catheter-based intervention of thrombosed and failing dialysis accesses significantly prolongs patency and usefulness of dialysis accesses. The expanding use of fistulas, improved detection of early access failure, and selective use of bailout stents should enhance long-term access patency. © 2005 Wiley-Liss, Inc. [source]