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Balloon Catheter (balloon + catheter)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

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]

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]

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]

Distortion of Right Superior Pulmonary Vein Anatomy by Balloon Catheters as a Contributor to Phrenic Nerve Injury

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2009
YASUO 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]

Appling the abdominal aortic-balloon occluding combine with blood pressure sensor of dorsal artery of foot to control bleeding during the pelvic and sacrum tumors surgery

JOURNAL OF SURGICAL ONCOLOGY, Issue 7 2008
Liu Yang MD
Abstract Background and Objectives To investigate the feasibilities of reducing intraoperative hemorrhage and improving the safety of pelvic and sacrum tumor surgery using sizing balloon occluding abdominal aorta. Method From May 2001 to May 2007, 18 patients were diagnosed as sacrum or pelvic tumor and underwent surgery in our institution. Balloon catheters were placed via femoral artery to occlude the abdominal aorta of pelvic tumor and sacrum region undergoing the sacrum resection or half pelvis resection and replacement operation in 12 patients. A sizing balloon was used to occlude the abdominal aorta for 60 min in assisting with resection of pelvic and sacral tumors. Results After the abdominal aorta was occluded, much less intraoperative hemorrhage was found, and the average blood loss was only 280 ml (range 200,600 ml). This procedure assisted the surgeon in identifying clearly the surgical margin and neurovascular structure surrounded by the tumors. The blood pressure remained stable during the operation. And the function of the kidney, the pelvis organs and the lower extremities were normal. Conclusion Intraoperative abdominal aorta occluding may effectively control intraoperative hemorrhage, thus assisting the surgeon in the complete and safe resection of pelvic and sacrum tumors. J. Surg. Oncol. 2008;97:626,628. © 2008 Wiley-Liss, Inc. [source]

THERAPEUTIC FISTULOSCOPY FOR THE MANAGEMENT OF PROLONGED POSTOPERATIVE INTRA-ABDOMINAL ABSCESS CAUSED BY SMALL INTESTINAL PINHOLE PERFORATION

DIGESTIVE ENDOSCOPY, Issue 4 2005
Yoshihisa Saida
Fistuloscopy is an effective treatment for intractable fistula, a sometimes difficult to manage postoperative intra-abdominal complication. A case of a 69-year-old male with an abdominal abscess after he underwent right hemi-colectomy for cecum cancer with invasions into the ileum and sigmoid colon is reported. A re-operation for lavage and drainage was performed 2 weeks after surgery. However, no obvious origin for the pus was located. Although physiological saline lavage was repeatedly performed, the effusion of pus persisted in the drain at the midline incision about 7 months after surgery. Then, fistuloscopy with an upper gastrointestinal endoscope was performed through the hole of the tube. A pinhole that produced a bubble just below the midline incision was observed. Then, an endoscopic retrograde cholangiopancreatography (ERCP) tube was inserted to obtain images of the small intestine by fluorography and findings suggested a diagnosis of perforation of the small intestine, which appeared to explain why resolution of the abscess was prolonged. After direct drainage to the small intestine with a 40-cm-long 7 Fr percutaneous transhepatic cholangio drainage (PTCD) balloon catheter, pus from the tube notably decreased. After confirming that the abscess cavity had disappeared by abdominal computed tomography scan, the PTCD catheter was extracted about 8 months after primary surgery. Since then, no recurrence of cancer or abscess has been observed. In cases of intractable postoperative intra-abdominal abscess, fistuloscopy using smaller diameter gastrointestinal endoscopy appears to be a valuable diagnostic tool. [source]

The lower esophageal sphincter strength in patients with gastroesophageal reflux before and after laparoscopic Nissen fundoplication

DISEASES OF THE ESOPHAGUS, Issue 1 2007
J. H. Schneider
SUMMARY., Lower esophageal sphincter pressure (LESP) and sphincter strength (LESS) were measured before and after short and floppy laparoscopic Nissen fundoplication (LNF) in 38 patients with severe gastro-esophageal reflux disease (GERD). These patients were compared with a control group of 23 healthy volunteers. GERD was assessed by stationary manometry, 24-h pH recordings and endoscopy. LESS was verified by motorized pull-back of an air-filled balloon catheter from the stomach into the esophagus. The catheter assembly was well tolerated by all study participants. LESP increased significantly after operation from 8 mmHg to 14 mmHg (75% of normal values; P < 0.0001), but compared to the control group, LESP (22 mmHg) decreased significantly (P < 0.002). In the control group and in patients with GERD, LESP and LESS showed excellent correlation (r = 0.97, r = 0.94, respectively). After LNF, LESS increased significantly from 0.6 to 1.6 N (P < 0.0001), about 166%. We conclude that the measurement of LESS is able to explain the discrepancy between satisfactory NF operation and the distinct increase of postoperative LESP. The evaluation of LESS is a helpful tool in assessing functional understanding of laparoscopic Nissen fundoplication with a short and floppy wrap. [source]

Intraoperative transesophageal echocardiography for inferior vena caval tumor thrombus in renal cell carcinoma

INTERNATIONAL JOURNAL OF UROLOGY, Issue 4 2004
TAKEHIRO OIKAWA
Abstract Background : We investigated the advantages of intraoperative transesophageal echocardiography (TEE) during inferior vena caval tumor thrombectomy in renal cell carcinoma (RCC). Methods : Five patients with RCC that extended into the inferior vena cava (IVC) underwent radical nephrectomy. To remove the tumor thrombus in the IVC, an inflated Fogarty balloon catheter was used to pull the thrombus below the level of the hepatic veins with real-time TEE monitoring. Results : In all cases, TEE monitoring during surgery provided an accurate and excellent view of the IVC thrombus. TEE was particularly helpful for the thrombectomy to minimize hepatic mobilization by using occlusion balloon catheter in two patients whose thrombus extended to the intrahepatic IVC. Conclusions : Intraoperative real-time TEE monitoring is a safe, minimally invasive technique that can provide accurate information regarding the presence and extent of IVC involvement, guidance for placement of a vena caval clamp, confirmation of complete removal of the IVC thrombus and intervention using catheters to assist in thrombectomy. [source]

Minimally Invasive Transventricular Implantation of Pulmonary Xenograft

JOURNAL OF CARDIAC SURGERY, Issue 4 2008
Howaida 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]

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

Decreased portal flow volume increases the area of necrosis caused by radio frequency ablation in pigs

LIVER INTERNATIONAL, Issue 3 2007
Tsuyoshi Yoshimoto
Abstract Background/aims: Although radio frequency ablation (RFA) has been widely accepted as an effective treatment for hepatocellular carcinoma (HCC), severe complications are not uncommon. Major complications seem to occur as a result of over-ablation beyond the intended area. As most patients with HCC have underlying cirrhosis, we speculated that decreased portal flow might cause the necrosis associated with RFA. To confirm this hypothesis, we examined the area of necrosis resulting from RFA under varying conditions of portal flow in a porcine model. Methods: RFA was performed using ultrasonographic guidance in anesthetized pigs. During the RFA procedure, portal flow was regulated by a balloon catheter, which was set in a portal trunk. The necrosis area was measured after sacrifice and was compared with the hyperechoic area that appeared during ablation. In another session, RFA was performed close to the hepatic vein and endothelial damage was examined. Results: The necrosis area caused by RFA was significantly larger when the portal flow volume was decreased by 50% or more. The hyperechoic lesion was always larger than the area of pathological necrosis regardless of portal flow volume. Under conditions of decreased portal flow, the vessel endothelium near the ablated area was more readily damaged. Conclusion: Decreased portal flow volume resulted in enlargement of the area of necrosis caused by RFA. Our results indicate that over-ablation could easily occur in patients with advanced cirrhosis, and that this could lead to major complications. Ultrasonographic guidance may be helpful for avoiding over-ablation. [source]

Venous rupture during percutaneous treatment of hemodialysis fistulas and grafts,

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2009
John A. Bittl MD
Abstract Objectives: The aim of this study was to analyze the risk and consequences of venous rupture during angioplasty of malfunctioning hemodialysis grafts and fistulas. Background: Venous stenoses in the outflow limb of hemodialysis accesses often require ultra-high balloon pressure for optimal dilatation. Methods: Baseline characteristics and outcomes were analyzed for a consecutive series of patients treated between 1999 and 2008. Results: Venous rupture or perforation occurred in 11 of 1242 (0.9%) procedures. No patient with a rupture or perforation died or required emergency or urgent surgical repair. Two of 11 patients (18.2%) required transfusions, 8 of 11 patients (72.7%) required stenting, and 6 of 8 (75.0%) who needed stenting received covered stents to achieve hemostasis. Rupture led to access thrombosis within 30 days in 9 of 11 cases (82%). Multivariable logistical regression analysis suggested that using a balloon catheter more than 2 mm larger than the diameter of the hemodialysis access or using peripheral cutting balloons increased the risk of rupture or perforation. Conclusions: Rupture or perforation is a rare complication of treatment of malfunctioning hemodialysis grafts and fistulas. The complication may be managed with nonsurgical methods and might be avoided by optimal balloon selection and sizing. © 2009 Wiley-Liss, Inc. [source]

Results of the multicenter first-in-man study of a novel scoring balloon catheter for the treatment of infra-popliteal peripheral arterial disease

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2007
Dierk Scheinert MD
Abstract Objective: To evaluate the AngioSculpt® (ASC), a novel scoring balloon catheter designed to treat complex diffuse fibro-calcific atherosclerotic lesions and avoid device slippage during deployment, in patients with infra-popliteal disease. Methods: The ASC incorporates a flexible nitinol scoring element containing three or more spiral struts which encircle a minimally compliant balloon to create focal concentration of the dilating force. Patients scheduled for percutaneous intervention of infra-popliteal arteries or planned amputation and with a reference vessel diameter of 1.5,3.5 mm were included in the study. Results: A total of 42 patients and 56 lesions were treated at five sites. Of these, 38 patients (90.5%) presented with critical limb ischemia (Rutherford Class , 4). The ASC was successfully deployed in 98.2% (55/56) of lesions attempted and was used as primary therapy without stenting in 89.3% (50/56). Lesion morphology was complex, including moderate/severe calcification in 73%, lesion length 33.9 ± 42.2 mm, bifurcation in 26.8%, and ostial in 12.5%. There was no significant device slippage and no perforations. Post-ASC dissections occurred in only six (10.7%) lesions and were minor or resolved with stenting. In 13 patients initially referred for amputation, ASC treatment resulted in limb salvage. Conclusions: The ASC is highly effective in a broad range of complex lesion morphologies, in most cases as stand-alone therapy, is associated with a very low complication rate and avoids device slippage during deployment. Additional studies are planned to assess the long term efficacy of this promising new technology. © 2007 Wiley-Liss, Inc. [source]

Balloon Debanding the Pulmonary Artery: In Vitro Studies and Early Clinical Experience

CONGENITAL HEART DISEASE, Issue 4 2009
Gareth J. Morgan MPhil
ABSTRACT Despite increasing corrective procedures for children with congenital heart disease, there remains a place for surgical banding of the main pulmonary artery (PA). In the vast majority of cases, these bands eventually need to be removed. We examined three cases of percutaneous disruption of PA bands using balloon catheters at our institution. We also performed an in vitro study of PA band disruption mechanism and disruption pressure. Our in vitro study suggested a predictable burst pressure for PA bands over the range of diameters routinely used in pediatric practice. Of three patients who underwent interventional debanding, two patients had successful disruption of their PA bands with no reintervention at 19 months and 23 months follow up. Balloon disruption of surgical PA bands may offer a less invasive alternative to surgical band removal. In vitro analysis suggests that the burst pressure required and mechanism of disruption are predictable. [source]

The mechanisms of coronary restenosis: insights from experimental models

INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 2 2000
Gordon A.A. Ferns
Since its introduction into clinical practice, more than 20 years ago, percutaneous transluminal coronary angioplasty (PTCA) has proven to be an effective, minimally invasive alternative to coronary artery bypass grafting (CABG). During this time there have been great improvements in the design of balloon catheters, operative procedures and adjuvant drug therapy, and this has resulted in low rates of primary failure and short-term complications. However, the potential benefits of angioplasty are diminished by the high rate of recurrent disease. Up to 40% of patients undergoing angioplasty develop clinically significant restenosis within a year of the procedure. Although the deployment of endovascular stents at the time of angioplasty improves the short-term outcome, ,in-stent' stenosis remains an enduring problem. In order to gain an insight into the mechanisms of restenosis, several experimental models of angioplasty have been developed. These have been used together with the tools provided by recent advances in molecular biology and catheter design to investigate restenosis in detail. It is now possible to deliver highly specific molecular antagonists, such as antisense gene sequences, to the site of injury. The knowledge provided by these studies may ultimately lead to novel forms of intervention. The present review is a synopsis of our current understanding of the pathological mechanisms of restenosis. [source]

Intranasal cooling with or without intravenous cold fluids during and after cardiac arrest in pigs

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2010
L. COVACIU
Background: Intranasal balloon catheters circulated with cold saline have previously been used for the induction and maintenance of selective brain cooling in pigs with normal circulation. In the present study, we investigated the feasibility of therapeutic hypothermia initiation, maintenance and rewarming using such intranasal balloon catheters with or without addition of intravenous ice-cold fluids during and after cardiac arrest treatment in pigs. Material and methods: Cardiac arrest was induced in 20 anaesthetised pigs. Following 8 min of cardiac arrest and 1 min of cardiopulmonary resuscitation (CPR), cooling was initiated after randomisation with either intranasal cooling (N) or combined with intravenous ice-cold fluids (N+S). Hypothermia was maintained for 180 min, followed by 180 min of rewarming. Brain and oesophageal temperatures, haemodynamic variables and intracranial pressure (ICP) were recorded. Results: Brain temperatures reductions after cooling did not differ (3.8 ± 0.7 °C in the N group and 4.3 ± 1.5 °C in the N+S group; P=0.47). The corresponding body temperature reductions were 3.6 ± 1.2 °C and 4.6 ± 1.5 °C (P=0.1). The resuscitation outcome was similar in both groups. Mixed venous oxygen saturation was lower in the N group after cooling and rewarming (P=0.024 and 0.002, respectively) as compared with the N+S group. ICP was higher after rewarming in the N group (25.2 ± 2.9 mmHg; P=0.01) than in the N+S group (15.7 ± 3.3 mmHg). Conclusions: Intranasal balloon catheters can be used for therapeutic hypothermia initiation, maintenance and rewarming during CPR and after successful resuscitation in pigs. [source]

An Unusual Case of an Accessory Coronary Artery to Pulmonary Artery Fistula:

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2004
Successful Closure with Transcatheter Coil Embolization
Coronary artery fistulae (CAF) are rare congenital anomalies. Surgical ligation is the standard treatment for symptomatic CAF, but is associated with higher morbidity. In a select group of patients, transcatheter coil embolization (TCE) is a reasonable alternative to standard surgical treatment. In this article, we present a unique (not previously reported) case of a tortuous accessory anomalous right coronary artery to pulmonary artery fistula with coronary steal phenomenon. TCE of highly tortuous fistulae can be technically difficult and are usually referred for surgery. In this case report we describe how utilization of adult coronary interventional wires and balloon catheters may help overcome some of the technical difficulties encountered with catheter-based closure of CAF. (J Interven Cardiol 2004;17:59,63) [source]

Treatment of Palmaz-Schatz In-stent Restenosis: 6,Month Clinical Follow-up

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2000
HUAY-CHEEM TAN M.D.
To identify predictors of Palmaz-Schatz in-stent restenosis and determine outcomes of treatment, we assessed 6,month outcomes in 402 patients who had coronary intervention with stent placement; 60 (15%) developed angiographic and clinical evidence of restenosis. Predictors of restenosis included family history of cardiovascular disease, prior bypass surgery, nonelective stenting, stenting of a vein graft, and multiple stents. Of 60 patients with stent restenosis, 47 had repeat percutaneous intervention and 10 had bypass surgery; only 1 of these 10 patients developed symptoms requiring repeat revascularization. Of the 47 with repeat percutaneous intervention, 32 (68%) had conventional balloon angioplasty; the others had perfusion balloon catheters, laser ablation, and repeat coronary stenting. During follow-up, 22 (47%) of these 47 patients suffered recurrent angina, myocardial infarction, or death. A third revascularization procedure was performed in 14 (30%), including 5 referred for bypass. This study shows the limitations of percutaneous modalities for patients with Palmaz-Schatz in-stem restenosis. Such patients are likely to have recurrent symptoms and to undergo repeat target-vessel revascularization. [source]

Endovascular stent implantation in the pulmonary arteries of infants and children without the use of a long vascular sheath

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2002
Robert H. Pass MD
Abstract Endovascular stent implantation for pulmonary artery stenosis requires the use of a long, large-bore vascular sheath to insure precise implantation without embolization or malposition. A long vascular sheath may be difficult to position and usage may be associated with vascular compromise and/or hemodynamic embarrassment, especially in infants and small children. We report a new technique for pulmonary artery endovascular stent implantation without the use of a long sheath. From December 2000 to May 2001, 10 patients underwent implantation of 13 Palmaz Corinthian premounted biliary transhepatic stents for pulmonary artery stenosis. Median age was 0.8 years (range, 0.5,18.5) and median weight was 11.8 kg (range, 4.6,65). Patient diagnoses were tetralogy of Fallot (five), double outlet right ventricle (three), branch peripheral pulmonary artery stenosis (two), single ventricle s/p cavopulmonary shunt (one), and truncus arteriosus (one). All Palmaz Corinthian stents were delivered uncovered on Cordis Opta LP balloon catheters via short sheaths (6,7 Fr); super-stiff guidewires were not always necessary. These stents, with a maximal expanded diameter of 12 mm, were placed for peripheral pulmonary artery stenosis as a definitive procedure or at the pulmonary artery bifurcation in patients who were expected to undergo future open heart surgery. The stents were initially implanted on 4, 6, or 8 mm balloon catheters and further expanded if needed. Stents were placed in the right pulmonary artery alone in three patients, left pulmonary artery alone in four patients, and side-by-side stents were implanted simultaneously in three patients. All thirteen stents were implanted successfully in the desired location without stent malposition or embolization. Mean angiographic diameter increased from 2.5 ± 1.5 to 5.7 ± 1.4 mm (P < 0.01) and peak systolic ejection gradients decreased from 44 ± 22 to 14 ± 11.6 mm Hg (P < 0.01). The uncovered delivery of the premounted Palmaz Corinthian stent allowed for precise and safe endovascular stent implantation without the hemodynamic and technical problems associated with long vascular sheath usage. This technique is useful for the palliation of proximal pulmonary artery stenosis and is effective definitive treatment for peripheral pulmonary artery stenosis in small infants and children. Cathet Cardiovasc Intervent 2002;55:505,509. © 2002 Wiley-Liss, Inc. [source]