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Balloon
Kinds of Balloon Terms modified by Balloon Selected AbstractsCutting Balloon for In-Stent Restenosis:JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2004Acute, Long-Term Results Introduction: Conventional percutaneous coronary intervention for the treatment of in-stent restenosis (ISR) has shown a high rate of ISR (30,55%). Considering the need for both extrusion of hyperplastic intima and additional stent expansion, a cutting balloon might be more effective for the treatment of ISR. Methods: We prospectively assessed the immediate and 8-month outcome of balloon angioplasty using the Barath Cutting Balloon in 100 consecutive patients (mean age: 60.5 ± 10.8 years, 71% male). Results: In 73 lesions (73%), a good result was reached with the cutting balloon only. In 21 lesions (21%) postdilatation and in 6 lesions (6%) predilatation with a conventional balloon was necessary. The mean inflation pressure was 8.7 ± 2.0 (range: 6.0,18.0) atm. Before the procedure the mean minimal luminal diameter (MLD) was 0.95 ± 0.45 mm. Quantitative coronary analysis showed a mean diameter stenosis of 65%± 16%. Immediately after the procedure the mean MLD was 2.42 ± 0.54 mm with a mean diameter stenosis of 19%± 13%. Two patients died during the follow-up period (1 stroke, 1 nonvascular). At 8-month follow-up 26 patients (26%) reported to have anginal complaints CCS class II,IV of whom 16 (16%) needed target lesion revascularization. Conclusion: Treatment of ISR using the Barath Cutting Balloon can be performed safely with good immediate results and a relatively low need for repeated target lesion revascularization at 8-month follow-up. [source] Review article: recent advances in the management of bleeding gastric varicesALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2006D. TRIPATHI Summary Gastric variceal bleeding can be challenging to the clinician. Tissue adhesives can control acute bleeding in over 80%, with rebleeding rates of 20,30%, and should be first-line therapy where available. Endoscopic ultrasound can assist in better eradication of varices. The potential risks of damage to equipment and embolic phenomena can be minimized with careful attention to technique. Variceal band ligation is an alternative to tissue adhesives for the management of acute bleeding, but not for secondary prevention due to a higher rate of rebleeding. Endoscopic therapy with human thrombin appears promising, with initial haemostasis rates typically over 90%. The lack of controlled studies for thrombin prevents universal recommendation outside of clinical trials. Balloon occluded retrograde transvenous obliteration is a recent technique for patients with gastrorenal shunts, although its use is limited to clinical trials. Transjugular intrahepatic portosystemic stent shunt is an option for refractory bleeding and secondary prophylaxis, with uncontrolled studies demonstrating initial haemostasis obtained in over 90%, and rebleeding rates of 15,30%. Non-cardioselective , -blockers are an alternative to transjugular intrahepatic portosystemic stent shunt for secondary prophylaxis, although the evidence is limited. Shunt surgery should be considered in well-compensated patients. Splenectomy or embolization is an option in patients with segmental portal hypertension. [source] Coronary Vein Angioplasty with Noncompliant Balloon for Resistant Coronary Vein Stenosis During Left Ventricular Lead ImplantationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2008KETUL CHAUHAN M.D. This report describes a patient who underwent cardiac resynchronization therapy (CRT) in the setting of a severe stenosis in the lateral coronary vein that prevented passage of a left ventricular lead. The stenosis was unresponsive to standard compliant balloon dilatation but was successfully treated with a noncompliant balloon. Venoplasty with noncompliant balloon should be considered for resistant coronary vein stenosis encountered during CRT device implantation. [source] Variations in Aortic Pressure Affect the Mechanics of the Intra-Aortic Balloon: An In Vitro InvestigationARTIFICIAL ORGANS, Issue 7 2010Giovanni Biglino Abstract This study aims to investigate the mechanics of the intra-aortic balloon (IAB) under different aortic pressure (Pao) and inclination (0,75°). Pressure and flow were measured in an artificial aorta during IAB pumping with a frequency of 1:3. Volume displaced toward the "coronary arteries" during inflation (Vprox) and "intra-aortic" pressure reduction during deflation (Pr) were derived. IAB duration of inflation and deflation was determined with a high-speed camera visualization. When the aorta was horizontal, Pao raised from 45 mm Hg to 115 mm Hg, Vprox reduced by 18% (25.0 ± 1.0 mL vs. 30.4 ± 1.9 mL) and Pr increased by 117% (106.4 ± 0.3 mm Hg vs. 48.9 ± 0.6 mm Hg). When the aorta was inclined, at low Pao of 45 mm Hg, Vprox was reduced by 30% from 0° to 45° (19.8 ± 2.3 mL vs. 28.3 ± 1.7 mL) and Pr was reduced by 66% (16.5 ± 0.1 mm Hg vs. 48.9 ± 0.6 mm Hg). However, at high Pao of 115 mm Hg, Vprox remained unchanged with increasing angle (20.0 ± 1.0 mL) and Pr was reduced by 24% (80.6 ± 0.8 mm Hg vs. 106.4 ± 0.3 mm Hg). Increasing Pao increased duration of inflation. At low Pao, increasing angle resulted in increasing duration of inflation, but at high Pao, increasing angle had the opposite effect. Duration of deflation generally decreased with Pao and increased with increasing angle. The IAB pump is affected by both Pao and angle, indicating that non-normotensive patients or patients in the semi-recumbent position might not receive the full benefits of IAB counterpulsation. [source] Gastric tone, volume and emptying after implantation of an intragastric balloon for weight controlNEUROGASTROENTEROLOGY & MOTILITY, Issue 9 2010S. Layec Abstract Background, The intragastric balloon, filled with air or liquid is used before elective bariatric surgery because its efficacy is limited. This might be the consequence of altered gastric functions. Therefore, we aimed to investigate, in an animal model, the changes in gastric motility and emptying induced by long-term insertion of a balloon used for weight reduction. Methods, Ten Göttingen mini-pigs were allocated into two groups with and without an intragastric balloon for 5 months. Balloons were inserted under endoscopy during general anesthesia and were filled with 350 mL of air. Gastric emptying was evaluated by scintigraphy. Gastric volume was measured by single photon emission computed tomography and proximal gastric compliance obtained using an electronic barostat. Changes in vagal tone were assessed by heart rate variability (HRV). Key Results, After balloon insertion, gastric volume was significantly increased (2047 ± 114.8 cm3 after vs 1674 ± 142.5 cm3 before insertion, P < 0.05). Gastric compliance was also larger in balloon group (219 ± 23.4 mL mmHg,1 in balloon vs 168 ± 7.7 mL mmHg,1 in control group). Gastric emptying was reduced after insertion of the balloon (T1/2 = 204 ± 28.8 min vs 159 ± 25.4 before vs after insertion). High frequency components of the spectral analysis of HRV, representing vagal tone, were increased in balloon group. Conclusions & Inferences, The proximal stomach was enlarged after the insertion of a balloon in the stomach as a consequence of an increased gastric compliance. This change in compliance was probably causative for a reduction in gastric emptying rate of solids. These alterations were associated with increased vagal tone. [source] The Material Transformations of AMID (cero9) Social Oxygen BalloonsARCHITECTURAL DESIGN, Issue 3 2010David Gissen Abstract For Spanish practice AMID (cero9), the proposal for an urban park on a restricted site in the Ventilla district of Madrid offered the chance to reconnect with nature through an experimentation with material metamorphosis. Guest-editor David Gissen describes how the project Social Oxygen Balloons with its ,metabolisms' or matter-changes, most apparent in the wall structure, stem from Gottfried Semper's concept of Stoffweschel. Copyright © 2010 John Wiley & Sons, Ltd. [source] Catheter-Assisted Vein Sclerotherapy: A New Approach for Sclerotherapy of the Greater Saphenous Vein with a Double-Lumen Balloon CatheterDERMATOLOGIC SURGERY, Issue 4 2007JENS 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] ENDOSCOPIC NECROSECTOMY UNDER DIRECT VISION AFTER ENDOSCOPIC ULTRASOUND-GUIDED CYSTGASTROSTOMY FOR ORGANIZED PANCREATIC NECROSISDIGESTIVE ENDOSCOPY, Issue 1 2008Takeshi Hisa A 56-year-old man was referred for an enlarging pancreatic pseudocyst that developed after severe acute pancreatitis with gallstones. Abdominal ultrasound showed a huge cystic lesion with a large amount of solid high echoic components. Arterial phase contrast-enhanced computed tomography scan revealed arteries across the cystic cavity. Stents were placed after endoscopic ultrasound-guided cystgastrostomy; however, the stents were obstructed by necrotic debris, and secondary infection of the pseudocyst occurred. Therefore, the cystgastrostomy was dilated by a dilation balloon, and a forward-viewing endoscope was inserted into the cystic cavity. Many vessels and a large amount of necrotic debris existed in the cavity. Under direct vision, all necrotic debris was safely removed using a retrieval net and forceps. One year after this procedure, there was no recurrence. Our case indicates that peripancreatic fat necrosis can cause exposure of vessels across/along the cystic cavity, and blind necrosectomy should be avoided. [source] COMPARING BALLOON DIAMETER ON PERFORMING ENDOSCOPIC PAPILLARY BALLOON DILATATION WITH ISOSORBIDE DINITRATE DRIP INFUSION FOR REMOVAL OF BILE DUCT STONESDIGESTIVE ENDOSCOPY, Issue 4 2004Hiroshi Nakagawa Background:, Endoscopic papillary balloon dilatation (EPBD) is one of the methods to remove bile duct stones. EPBD might preserve the function of the sphincter of Oddi despite the potential risk of acute pancreatitis. There are only a few reports of EPBD reducing the risk of acute pancreatitis and, at same time, preserving the function of the sphincter of Oddi. Methods:, We performed EPBD for bile duct stone removal in 60 patients using two balloons with different diameters. Patients were randomized to EPBD with a 6 mm balloon (n = 30) or an 8 mm balloon (n = 30). In both groups, isosorbide dinitrate (ISDN) was infused in a rate of 5 mg/h while low pressure EPBD were being performed. The pressure of the sphincter of Oddi was observed before and after the EPBD procedures. Also, serum amylase level after EPBD was observed for both groups. Results:, Serum amylase level of the 6 mm group was signi,cantly higher than that of the 8 mm group (P < 0.05). Acute pancreatitis occurred in two patients ( 6.7%) in the 6 mm group whereas no case was observed for the 8 mm group. The rates of duct clearance were 93% in the 6 mm group and 100% in the 8 mm group. Stone removals were dif,cult in seven cases with 6 mm balloon dilatations due to the narrow ori,ces of the papilla. In the 6 mm group, there was no signi,cant difference between the basal sphincter of Oddi pressure (BSOP) and the phasic sphincter of Oddi pressure (PSOP) before and after EPBD. However in the 8 mm group, the BSOP observed after the EPBD procedure was signi,cantly higher than BSOP before the treatments. Within this group, BSOP values after EPBD were preserved by approximately 80% of the BSOP values before the treatments. In contrast, there was no signi,cant difference in PSOP before and after the treatments. Regarding the stone numbers, no signi,cant difference was observed in BSOP before and after the treatments for the 6 mm group with less than two stones. Also, as for stone size, no signi,cant difference was observed in BSOP before and after the treatments for the 6 mm group with stones of less than 6 mm in diameter. Conclusion:, We are now conducting EPBD with ISDN infusion using a 6 mm balloon for a patient who has less than two stones with size not exceeding 6 mm in diameter. An 8 mm balloon is used for a patient with more than two stones or a stone greater than 6 mm in size. [source] Endoscopic Injection Sclerotherapy for the Treatment of Recurrent Esophageal Varices after Esophageal TransectionDIGESTIVE ENDOSCOPY, Issue 3 2002Hiroshi Yoshida Background: ,We examined the hemodynamic changes associated with recurrent esophageal varices after esophageal transection (ET) and evaluated the effectiveness of endoscopic injection sclerotherapy (EIS) as the treatment for these varices. Methods: ,Nineteen patients with recurrent esophageal varices after ET were treated by EIS. Endoscopic varicealography during injection sclerotherapy, following oral blockage of flow by a balloon, identified three patterns: (i) type 1: common type, continuous filling by the feeder vessel of the varix; (ii) type 2: retrograde-disappearing type, confirmed hepatofugal flow; and (iii) type 3: immediate washout type, immediate washout of contrast medium. Results: ,Angiography revealed that the hepatofugal feeder vessel was the right gastric vein in all cases. Fourteen patients (73.7%) were classified as type 1, 4 patients (21.1%) as type 2, and 1 patient (5.3%) as type 3. Fewer treatment sessions were required in type 1 than in type 2 (P < 0.005). Recurrent varices were completely eradicated in all patients except the patient with type 3 disease. Cumulative re-recurrence rates at 5 and 10 years were similar for types 1 and 2 (28.6 and 71.4%vs 25 and 25%, respectively). The cumulative survival rates after EIS at 5 and 10 years were also similar for types 1 and 2 (77.1 and 66.1%vs 66.7 and 66.7%). Conclusion: ,Endoscopic injection sclerotherapy is an effective treatment for recurrent esophageal varices after ET, except in type 3 disease. Our classification based on endoscopic varicealography during injection sclerotherapy provides knowledge of blood flow within the varices that helps to inform the treatment strategy. [source] Adolescent Foley Catheter Technique for Visualizing Hymenal Injuries in Adolescent Sexual AssaultACADEMIC EMERGENCY MEDICINE, Issue 9 2003Jeffrey S. Jones MD Abstract Objectives: To determine the usefulness of the Foley catheter balloon technique for visualizing injuries of the estrogenized hymen in adolescent sexual assault victims compared with supine labial traction. Methods: A prospective clinical trial of 20 adolescent (age 13,16 years old) victims of sexual assault evaluated at a free-standing Nurse Examiner Clinic was conducted over a four-month study period. The clinic, affiliated with an emergency medicine residency program, is staffed by registered nurses who have been specially trained to perform medicolegal examinations using colposcopy with digital imaging. The Foley catheter technique uses an inflated balloon in the distal vaginal vault to expand the estrogenized hymen to its full capacity so that the edge may be readily visualized for signs of trauma. The Foley technique was compared with gross inspection, using supine labial traction, to photodocument hymenal abnormalities. Photographs of the hymen were obtained using the labial traction technique and then with the Foley technique. Three emergency physicians independently examined each pair of photographs with high interrater agreement for the presence of injury (,= 0.88). Results: Twenty adolescent sexual assault victims volunteered for the study; mean age was 14.8 years. Gross inspection of the hymen using supine labial traction identified hymenal injuries in three patients (15%). Use of the Foley catheter balloon technique allowed identification of hymenal abnormalities in nine additional cases (60%). The common injuries to the hymen included lacerations (30%), followed by ecchymosis and abrasions. One patient (5%) voiced discomfort (mild pressure sensation) during inflation of the balloon. Conclusions: The Foley catheter balloon technique is a simple method allowing improved photodocumentation of hymenal trauma in adolescent sexual assault victims compared with supine labial traction. [source] A control analysis of interaction problem by fluid forceINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 7 2001Shoichiro Kato Abstract This paper presents a control analysis of displacement for a building. To control the vertical displacement of the building, control device of multi-balloons with water inside is introduced on the friction piles. Coupling through the water, soil, balloon and pile, the interaction problem is numerically solved. The soil is assumed to be a linear elastic body. The balloon and pile are also modelled as linear elastic truss and rigid-frame components. The water is assumed to be the two-dimensional incompressible Navier,Stokes flow. All components are discretized by the finite element method in space. The control analysis of vertical displacement by fluid force is performed for the purpose of keeping the building horizontal. One of the optimal control theory, the so-called Sakawa,Shindo method, is applied for the control analysis. Using this method, control flux of the water is determined so that position at the top of the balloon comes to be close to the objective position. Copyright © 2001 John Wiley & Sons, Ltd. [source] Optimal transportation meshfree approximation schemes for fluid and plastic flowsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 12 2010B. Li Abstract We develop an optimal transportation meshfree (OTM) method for simulating general solid and fluid flows, including fluid,structure interaction. The method combines concepts from optimal transportation theory with material-point sampling and max-ent meshfree interpolation. The proposed OTM method generalizes the Benamou,Brenier differential formulation of optimal mass transportation problems to problems including arbitrary geometries and constitutive behavior. The OTM method enforces mass transport and essential boundary conditions exactly and is free from tension instabilities. The OTM method exactly conserves linear and angular momentum and its convergence characteristics are verified in standard benchmark problems. We illustrate the range and scope of the method by means of two examples of application: the bouncing of a gas-filled balloon off a rigid wall; and the classical Taylor-anvil benchmark test extended to the hypervelocity range. Copyright © 2010 John Wiley & Sons, Ltd. [source] Cost-effective laparoscopic pyeloplasty: Single center experienceINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2003ASHOK KUMAR HEMAL Summary Objective:, Laparoscopic pyeloplasty (LPP) is a minimally invasive treatment option for ureteropelvic junction (UPJ) obstruction. We report here our experience of performing cost-effective LPP on 24 patients at a single center. Methods:, Between October 1999 and March 2002, LPP was performed in 24 patients (17 male, seven female; age range 8,51 years) including two patients who had failed previous endourologic treatments. In two patients with concomitant renal stones, laparoscopic pyelolithotomy was also performed. LPP was conducted in a cost-reductive manner by both transperitoneal (n = 12) and retroperitoneal (n = 12) access. To reduce the cost, an indigenous balloon to create the retroperitoneal space, reusable ports, ordinary polyglactin suture and intracorporeal free-hand suturing were employed. To reduce operative time, antegrade stenting was also performed in some cases. Results:, Laparoscopic Anderson,Hynes pyeloplasty was performed in 16, Foley Y,V pyeloplasty in five and Fenger pyeloplasty in three patients. One patient required conversion to open surgery due to tension at the anastomosis site during Anderson,Hynes pyeloplasty. The mean operating time, blood loss, analgesic (pethidine) requirement, duration of drain and hospital stay for the retroperitoneal and transperitoneal groups were 170.3 and 187.6 min, 102.2 and 145.9 mL, 125 and 136.4 mg, 2.1 and 2.5 days, and 3.4 and 4.3 days, respectively. No significant complications were encountered apart from prolonged ileus in three patients in the transperitoneal group. The mean follow-up period was 10.8 months with a range of 2,24 months. Postoperative renal scan was performed at 3 months in 21 patients, and 1 year in 11 patients. There was evidence of equivocal obstruction in one patient, but there were no obstructions in the remaining patients. Conclusion:, Although LPP is technically demanding, it is emerging as a viable, minimally invasive alternative to open pyeloplasty for UPJ obstruction with a success rate similar to that of open pyeloplasty. It allows the duplication of open surgery steps (unlike endoscopic procedures), thereby providing durable and sustained results. LPP can also be performed safely, effectively and efficiently in a cost-efficient manner. [source] Minimally Invasive Transventricular Implantation of Pulmonary XenograftJOURNAL OF CARDIAC SURGERY, Issue 4 2008Howaida Al Qethamy F.R.C.S., M.D. A number of ingenious techniques have been described for percutaneous aortic and pulmonary valve replacement as well as transventricular aortic valve replacement. We describe a technique for transventricular pulmonary valve replacement utilizing off-the-shelf bovine tissue valve, vascular stents, and simplified delivery system. After median sternotomy with limited exposure of the right ventricle, Contegra 200 pulmonary valve (Medtronic, Inc., Minneapolis, MN, USA) is transfixed inside a CP stent (NuMed, Inc., Hopkinton, NY, USA) using multiple 5/0 prolene sutures. The valve/stent composite is crimped on a Cristal balloon catheter (Balt, Montmorency, France). The valve/stent and the balloon are then introduced via a small purse-string placed at the RVOT. The stent/valve composite is then expanded in the pulmonary valve position. [source] Left Ventricular Reconstruction for Ischemic CardiomyopathyJOURNAL OF CARDIAC SURGERY, Issue 3 2002Vincent Dor M.D. The technique is conducted under a totally arrested heart; coronary revascularization is accomplished first. The mitral valve is checked by TEE and repaired if necessary. Endocardectomy and cryotherapy are used in case of ventricular tachycardia. At the limit between scarred and normal tissue, a continuous suture is tied on a balloon inflated at the theoretical diastolic volume of the patient, and a patch is fixed inside the ventricle. Autologous tissue can be also used. The experience of the author is more than 1000 cases since 1984. The global hospital mortality of the whole series is 7.3%, and 13% in patients with very poor ejection fraction (<30%). In the series of the last 3 years, these mortality rates are 4.8% and 7.9%, respectively. Both geometry and performances of the LV are improved, and the mean increase of ejection fraction is between 10 and 15 points. Three causes can explain delayed impairment; continuum in remodeling, lack in diastolic capacity, or absence of mitral repair. After an infarct, with or without successful coronary recanalization, that leaves a large asynergic scarred ventricle (50% of LV circumference), LVR is recommended to avoid or prevent permanent congestive heart failure with global dilatation. In end-stage ischemic cardiomyopathy with congestive heart failure, and poor response to full medical therapy, LVR, with acceptable risk, could slow down the remodeling and avoid or delay heart transplantation. [source] The Permanency of Pulmonary Vein Isolation Using a Balloon Cryoablation CatheterJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2010HUMERA 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] Distortion of Right Superior Pulmonary Vein Anatomy by Balloon Catheters as a Contributor to Phrenic Nerve InjuryJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2009YASUO OKUMURA M.D. Introduction: Cryothermal, HIFU, and laser catheter-based balloon technologies have been developed to simplify ablation for AF. Initial enthusiasm for their widespread use has been dampened by phrenic nerve (PN) injury. The interaction between PN and pulmonary vein (PV) geometry contributing to PN injury is unclear. Methods and Results: After right thoracotomy, the PN course along the epicardial right atrial surface was mapped directly in 10 dogs. The location of the PN and its relationship with the right superior (RS) PV, and potential RSPV surface distortions after balloon inflation were established by electroanatomic mapping. In 5 dogs, the PN was captured within the RSPV, but could not be stimulated in the remaining 5 dogs. The distance between the RSPV and the PN was significantly shorter in the captured group than in the noncaptured group (6.3 ± 3.1 mm vs 10.2 ± 3.2 mm, P < 0.001). Importantly, 96% of the captured sites within the RSPV were observed at a distance >5 mm into the PV. The inflated balloon surface anteriorly extended 5.6 ± 3.7 mm outside the PV diameter, with distortion of anatomy narrowing the distance from the balloon surface to the PN to 4.8 ± 2.3 mm. (Distance of the original RSPV-to-PN: 9.4 ± 2.7 mm, P < 0.001.) Conclusion: PN injury with balloon technologies may stem from anatomic distortion of the PV orifice/PN relationship, through increasing contact or shortening the relative distance between the ablation site and the PN, even without displacement of the balloon into the PV. These data are important in the refinement of these technologies to improve procedural safety. [source] Temporary Occlusion of the Great Cardiac Vein and Coronary Sinus to Facilitate Radiofrequency Catheter Ablation of the Mitral IsthmusJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2008ANDRE D'AVILA M.D. Introduction: Ablation of the mitral isthmus to achieve bidirectional conduction block is technically challenging, and incomplete block slows isthmus conduction and is often proarrhythmic. The presence of the blood pool in the coronary venous system may act as a heat-sink, thereby attenuating transmural RF lesion formation. This porcine study tested the hypothesis that elimination of this heat-sink effect by complete air occlusion of the coronary sinus (CS) would facilitate transmural endocardial ablation at the mitral isthmus. Methods: This study was performed in nine pigs using a 30 mm-long prototype linear CS balloon catheter able to occlude and displace the blood within the CS (the balloon was inflated with ,5 cc of air). Using a 3.5 mm irrigated catheter (35 W, 30 cc/min, 1 minute lesions), two sets of mitral isthmus ablation lines were placed per animal: one with the balloon deflated (CS open) and one inflated (CS Occluded). After ablation, gross pathological analysis of the linear lesions was performed. Results: A total of 17 ablation lines were placed: 7 with CS Occlusion, and 10 without occlusion. Despite similar biophysical characteristics of the individual lesions, lesion transmurality was consistently noted only when using the air-filled CS balloon. Conclusions: Temporary displacement of the venous blood pool using an air-filled CS balloon permits transmurality of mitral isthmus ablation; this may obviate the need for ablation within the CS to achieve bidirectional mitral isthmus conduction. [source] Ventricular Fibrillation Induced by Stretch Pulse: Implications for Sudden Death Due to Commotio CordisJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2006FRANK BODE M.D. Introduction: Nonpenetrating chest wall impact (commotio cordis) may lead to sudden cardiac death due to the acute initiation of ventricular fibrillation (VF). VF may result from sudden stretch during a vulnerable window, which is determined by repolarization inhomogeneity. Methods: We examined action potential morphologies and VF inducibility in response to sudden myocardial stretch in the left ventricle (LV). In six Langendorff perfused rabbit hearts, the LV was instrumented with a fluid-filled balloon. Increasing volume and pressure pulses were applied at different times of the cardiac cycle. Monophasic action potentials (MAPs) were recorded simultaneously from five LV epicardial sites. Inter-site dispersion of repolarization was calculated in the time and voltage domains. Results: Sudden balloon inflation induced VF when pressure pulses of 208,289 mmHg were applied within a window of 35,88 msec after MAP upstroke, a period of intrinsic increase in repolarization dispersion. During the pressure pulse, MAPs revealed an additional increase in repolarization dispersion (time domain) by 9 ± 6 msec (P < 0.01). The maximal difference in repolarization levels (voltage domain) between sites increased from 19 ± 3% to 26 ± 3% (P < 0.05). Earliest stretch-induced activation was observed near a site with early repolarization, while sites with late repolarization showed delayed activation. Conclusions: Sudden myocardial stretch can elicit VF when it occurs during a vulnerable window that is based on repolarization inhomogeneity. Stretch pulses applied during this vulnerable window can lead to nonuniform activation. Repolarization dispersion might play a crucial role in the occurrence of fatal tachyarrhythmias during commotio cordis. [source] Assessment of Pulmonary Vein Anatomic Variability by Magnetic Resonance Imaging:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2004Implications for Catheter Ablation Techniques for Atrial Fibrillation Introduction: Pulmonary vein (PV) isolation for atrial fibrillation (AF) currently is performed using either an ostial or an extra-ostial approach. The objective of this study was to analyze by three-dimensional (3D) magnetic resonance angiography (MRA) the anatomy of the PVs in order to detect structural variability that would impact the choice of ablation approach. Methods and Results: Three-dimensional MRA was performed in 105 patients undergoing PV isolation. The ostial diameter, branching pattern, and PV angulation were analyzed. Fifty-nine (56%) patients had the typical pattern of 4 PVs with 4 separate ostia, 30 (29%) patients had an additional PV, and 18 (17%) patients had a left common PV trunk. In two patients, there were three right-sided veins and a common left-sided trunk, giving rise to four ostia: three on the right and one on the left. Two different populations of right middle PVs were noted: one where the additional vein projected anteriorly to drain the right middle lobe and one posterior to drain the superior portion of the right lower lobe. The average intrapatient variability in PV diameter was 7.9 ± 4.2 mm. The PV ostium was <10 mm in 26 (25%) patients and >25 mm in 15 (14%) patients. The first branch originated 6.7 ± 2.3 mm from the ostium. The left superior, right superior, right inferior, and left inferior PVs were found to enter the left atrium at the following angles: 32 ± 13°, 131 ± 11°, 206 ± 16°, and 329 ± 14°, respectively. Forty-nine patients (47%) had at least one funnel shaped PV. Conclusion: This largest PV imaging study to date demonstrates that MRA is a valuable tool that allows detection of marked intrapatient and interpatient anatomic variability of the PVs. These findings suggest that, at least in some patients, circumferential extra-ostial left atrial encirclement of the PVs may be preferable to ostial PV isolation. These findings also may have significant implications on the future development of coil- and balloon-based catheter ablation designs for AF ablation. (J Cardiovasc Electrophysiol, Vol. 15, pp. 387-393, April 2004) [source] Usefulness of a New Radiofrequency Thermal Balloon Catheter for Pulmonary Vein Isolation:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2003A 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 Ventricular Pacing for Catheter Interventions in Congenital Aortic Stenosis and Coarctation: Effectiveness, Safety, and Rate Titration for Optimal ResultsJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2010CHETAN MEHTA M.B.B.S. Introduction: Infants and children with congenital aortic stenosis and coarctation of the aorta can be treated by catheter intervention. There are several pharmacological and mechanical techniques described to overcome the balloon movement; none, however, have proved entirely satisfactory. An alternative method to achieve balloon stability is the use of rapid ventricular pacing. We describe our experience with titrating the pacing rate and the use of this technique. Methods: A retrospective review of database was performed, to identify patients who underwent transcatheter intervention with rapid ventricular pacing. Invasive systemic pressures were documented with a catheter in the aorta. Rapid ventricular pacing was initiated at the rate of 180 per minute and increased by increments of 20 per minute to a rate required to achieve a drop in systemic pressure by 50% and a drop in pulse pressure by 25%. The balloon was inflated only after the desired pacing rate was reached. Pacing was continued until the balloon was completely deflated. Results: Thirty patients were identified, 29 of whom had interventions with rapid ventricular pacing. Balloon valvuloplasty of aortic valve was performed on 25 patients while 4 patients had stenting for coarctation by this technique. The rate of ventricular pacing required ranged from 200 to 260 per minute with a median rate of 240. Balloon stability at the time of intervention was achieved in 27 patients. Conclusion: Rapid ventricular pacing is a safe and effective method to provide transient decrease in cardiac output at the time of transcatheter interventions to achieve balloon stability. (J Interven Cardiol 2010;23:7,13) [source] Endovascular Interventions in Iliac and Infrainguinal Occlusive Artery DiseaseJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 6 2004JOHANNES RUEF M.D., M.Sc. Percutaneous endovascular procedures are increasingly applied to treat symptomatic peripheral occlusive artery disease. While the primary technical success and recanalization rates in iliac and infrainguinal interventions are high, differences in the long-term patency rates exist with respect to the anatomic localization, separating the iliac, femoropopliteal, and infrapopliteal arterial regions. In iliac arteries, even complex lesions can be recanalized with good long-term patency rates, especially when using self-expanding nitinol stents. In the infrainguinal arteries the method of choice is still under debate (e.g., balloon angioplasty vs stent implantation). A high restenosis rate represents one of the major limitations in femoropopliteal and infrapopliteal interventions. Therefore, additional methods and treatment strategies for peripheral interventions with the potential for future applications are under investigation and will be discussed such as drug-eluting stents, brachytherapy, subintimal angioplasty, laser angioplasty, atherectomy/thrombectomy, cutting balloon, polytetrafluoroethylene (PTFE)-covered stent grafts, biodegradable stents, and cryoplasty. The increasing amount of data on successful peripheral interventions supports the necessity to adapt and reevaluate the current consensus guidelines that were put together in 2000. [source] Cutting Balloon for In-Stent Restenosis:JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2004Acute, Long-Term Results Introduction: Conventional percutaneous coronary intervention for the treatment of in-stent restenosis (ISR) has shown a high rate of ISR (30,55%). Considering the need for both extrusion of hyperplastic intima and additional stent expansion, a cutting balloon might be more effective for the treatment of ISR. Methods: We prospectively assessed the immediate and 8-month outcome of balloon angioplasty using the Barath Cutting Balloon in 100 consecutive patients (mean age: 60.5 ± 10.8 years, 71% male). Results: In 73 lesions (73%), a good result was reached with the cutting balloon only. In 21 lesions (21%) postdilatation and in 6 lesions (6%) predilatation with a conventional balloon was necessary. The mean inflation pressure was 8.7 ± 2.0 (range: 6.0,18.0) atm. Before the procedure the mean minimal luminal diameter (MLD) was 0.95 ± 0.45 mm. Quantitative coronary analysis showed a mean diameter stenosis of 65%± 16%. Immediately after the procedure the mean MLD was 2.42 ± 0.54 mm with a mean diameter stenosis of 19%± 13%. Two patients died during the follow-up period (1 stroke, 1 nonvascular). At 8-month follow-up 26 patients (26%) reported to have anginal complaints CCS class II,IV of whom 16 (16%) needed target lesion revascularization. Conclusion: Treatment of ISR using the Barath Cutting Balloon can be performed safely with good immediate results and a relatively low need for repeated target lesion revascularization at 8-month follow-up. [source] Immediate and 3-Month Follow-Up Outcome After Cutting Balloon Angioplasty for Bifurcation LesionsJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2004HIDEO TAKEBAYASHI M.D. Balloon angioplasty of a bifurcation lesion is associated with lower rates of success and higher rates of complications than such treatment of lesions of most other morphologies. To date, the best device or procedure for bifurcation lesions has not been determined. The aim of this study was to compare the immediate and 3-month follow-up outcome of cutting balloon angioplasty (CBA) versus conventional balloon angioplasty (PTCA) for the treatment of bifurcation lesions. We treated 87 consecutive bifurcation lesions with CBA (n = 50) or PTCA (n = 37). Paired angiograms were analyzed by quantitative angiography, and angiographic follow-up was achieved for 93% of the lesions. The procedural success was 92% in the CBA group and 76% in the PTCA group (P < 0.05). Major in-hospital complications occurred in two lesions in the CBA group and six in the PTCA group (P = 0.05). The incidence of bail-out stenting in the CBA group was lower than in the conventional PTCA (8% vs 24%, P < 0.05). At the 3-month follow-up, the restenosis rate was 40% in the CBA group versus 67% in the PTCA group (P < 0.05). Clinical events during follow-up did not differ between the two groups. In conclusion, in comparison with PTCA, procedural success was greater and the restenosis rate lower with CBA. The results of this study support the use of the cutting balloon as optimal treatment for bifurcation lesions. (J Interven Cardiol 2004;17:1,7) [source] Catheter Closure of Coronary Artery FistulasJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2001SHAKEEL A. QURESHI F.R.C.P. Coronary artery fistulas are rare and vary widely in their morphological appearance and presentation. This paper presents experience of catheter closure of coronary artery fistulas in 40 patients. Catheter closure was performed with a variety of techniques, including detachable balloons, stainless steel coils, controlled-release coils, controlled-release patent ductus arteriosus (PDA) coils, and Amplatzer PDA plug. The vast majority of the fistulas were occluded with coils and in particular, controlled-release coils. Successful occlusion of the fistula was achieved in 39 (97%) of 40 patients. In one patient, the detachable balloon deflated prematurely and the patient underwent elective surgery. One 4-month-old infant died approximately 6 hours after the procedure. Immediate occlusion of the coronary artery fistula occurred in 33 (82%) of patients and late occlusion in 4 patients. Thus overall, total occlusion was achieved in 37 (97%) of 39 patients. The main complication was embolization of the occlusion device, which occurred in 6 (17%) of cases. In one of these cases, a detachable balloon deflated prematurely, and in five patients, coils embolized and were retrieved. In one of the patients, all six coils embolized 24 hours after the procedure but were retrieved, and further coils were implanted successfully. Controlled-release coils have made an important contribution to the technique of catheter closure of coronary artery fistulas. Catheter closure of these fistulas is an acceptable alternative to the standard surgical treatment. [source] Percutaneous Transluminal Angioplasty of the Anomalous Circumflex ArteryJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2001DIDIER BLANCHARD M.D. The technical experience reported in the literature concerning angioplasty in patients with anomalous origin of the left circumflex artery is limited. Balloon angioplasty seems to be a favorable approach for revascularization in these vessels, and major determinants of successful angioplasty are angiographic knowledge of their course and structure, appropriate selection of guiding catheter, and the possibility of advancing the balloon into the anomalous vessel. Five consecutive patients with severe atherosclerotic lesions on the anomalous left circumflex artery who underwent coronary angioplasty of the anomalous vessel are reported. Angiographic and clinical success were achieved in three patients with balloon alone and in one with stent implantation. (J Interven Cardiol 2001;14:11,16) [source] Direct Coronary Stenting in Noncomplex and Noncalcified Lesions: Immediate and Mid-term Results of a Prospective RegistryJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2000MARC BEDOSSA M.D. Stenting of coronary arteries is currently used in clinical practice. The aim of this prospective registry was to assess the feasibility and the safety of stent implantation without balloon predilatation in noncomplex and noncalcifed lesions. One hundred six stents were implanted in 85 patients who underwent percutaneous coronary angioplasty (PTCA) of native vessels (n = 95) or bypass grafts (n = 11). The lesions were type A (21%) or B1 (79%). The stent was a tubular or a coil stent in 71 ± and 29% of the cases, respectively. The angiographic success rate was 94%. The maximal pressure was 12.1 ± 2.1 atm. In only 7 cases, it was not possible to cross the stenosis with the stent, necessitating retrieval of it and predilation with a balloon before stent implantation. Three dissections after stent implantation were treated by a second stent implantation. The primary success rate was 98% (no acute closure or myocardial infarction). A clinical follow-up was obtained in 98% of patients with a mean delay of 6 ± 0.5 months. Eighty-one percent of patients were asymptomatic. The target lesion revascularization rate was 9.4%. Four patients underwent a new PTCA and four patients a coronary artery bypass graft surgery. This technique of stent implantation appears to be safe with good immediate and midterm results. A prospective randomized trial comparing this technique to the standard technique of stent delivery in noncomplex lesions is currently ongoing with an intravascular ultrasound substudy. [source] Fast and optimized T1 mapping technique for the noninvasive quantification of gastric secretionJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2008Reto Treier MSc Abstract Purpose To evaluate the noninvasive quantification of gastric secretion volume after administration of a labeled viscous glucose solution by fast T1 mapping. Materials and Methods T1 values of a series of labeled and diluted glucose solutions were measured in vitro to characterize the interrelationship between T1 and contrast agent concentration (CGd) as well as the dependency of relaxivity and reference T1 (T10) on the macromolecular concentration. Abdominal T1 mapping in five healthy volunteers of different body mass index was performed after filling an intragastric balloon with a labeled and diluted glucose solution. In additional ex vivo experiments, T1 values of gastric (GJ) and duodenal juice (DJ) and 0.1 N HCl solution were determined. Results A linear relationship between relaxivity and macromolecular concentration and between T10 and macromolecular concentration was found. The in vitro T1,CGd calibration curve was successfully validated in all volunteers. T1 values of GJ, DJ, and HCl (2939 msec vs. 2858 msec vs. 2760 msec) were close to the T1 of water (,3000 msec). Conclusion The presented method allows one to noninvasively quantify the spatial distribution of gastric secretory products in the human stomach and provides a valuable tool for evaluating the efficacy of drugs to stimulate/inhibit gastric secretion. J. Magn. Reson. Imaging 2008;28:96,102. © 2008 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||||||||