Home About us Contact
|
Home About us Contact | ||
|
|
||
PV Stenosis (pv + stenosis)
Selected AbstractsFirst 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 UnitJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2009AXEL 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] Substrate and Procedural Predictors of Outcomes After Catheter Ablation for Atrial Fibrillation in Patients with Hypertrophic CardiomyopathyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2008T. JARED BUNCH M.D. Background: Hypertrophic cardiomyopathy (HCM) is often accompanied by atrial fibrillation (AF) due to diastolic dysfunction, elevated left atrial pressure, and enlargement. Although catheter ablation for drug-refractory AF is an effective treatment, the efficacy in HCM remains to be established. Methods: Thirty-three consecutive patients (25 male, age 51 ± 11 years) with HCM underwent pulmonary vein (PV) isolation (n = 8) or wide area circumferential ablation with additional linear ablation (n = 25) for drug-refractory AF. Twelve-lead and 24-hour ambulating ECGs, echocardiograms, event monitor strips, and SF 36 quality of life (QOL) surveys were obtained before ablation and for routine follow-up. Results: Twenty-one (64%) patients had paroxysmal AF and 12 (36%) had persistent/permanent AF for 6.2 ± 5.2 years. The average ejection fraction was 0.63 ± 0.12. The average left atrial volume index was 70 ± 24 mL/m2. Over a follow-up of 1.5 ± 1.2 years, 1-year survival with AF elimination was 62%(Confidence Interval [CI]: 66-84) and with AF control was 75%(CI: 66-84). AF control was less likely in patients with a persistent/chronic AF, larger left atrial volumes, and more advanced diastolic disease. Additional linear ablation may improve outcomes in patient with severe left atrial enlargement and more advanced diastolic dysfunction. Two patients had a periprocedureal TIA, one PV stenosis, and one died after mitral valve replacement from prosthetic valve thrombosis. QOL scores improved from baseline at 3 and 12 months. Conclusion: Outcomes after AF ablation in patients with HCM are favorable. Diastolic dysfunction, left atrial enlargement, and AF subtype influence outcomes. Future studies of rhythm management approaches in HCM patients are required to clarify the optimal clinical approach. [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 StudyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2006SANJAY 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] 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] Anatomy of the Pulmonary Veins in Patients with Atrial Fibrillation and Effects of Segmental Ostial Ablation Analyzed by Computed TomographyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2003CHRISTOPH SCHARF M.D. Pulmonary Vein Anatomy.Introduction: The anatomic arrangement of pulmonary veins (PVs) is variable. No prior studies have quantitatively analyzed the effects of segmental ostial ablation on the PVs. The aim of this study was to determine the effect of segmental ostial radiofrequency ablation on PV anatomy in patients with atrial fibrillation (AF). Methods and Results: Three-dimensional models of the PVs were constructed from computed tomographic (CT) scans in 58 patients with AF undergoing segmental ostial ablation to isolate the PVs and in 10 control subjects without a history of AF. CT scans were repeated approximately 4 months later. PV and left atrial dimensions were measured with digital calipers. Four separate PV ostia were present in 47 subjects; 3 ostia were present in 2 subjects; and 5 ostia were present in 9 subjects. The superior PVs had a larger ostium than the inferior PVs. Patients with AF had a larger left atrial area between the PV ostia and larger ostial diameters than the controls. Segmental ostial ablation resulted in a 1.5 ± 3.2 mm narrowing of the ostial diameter. A 28% to 61% focal stenosis was present 7.6 ± 2.2 mm from the ostium in 3% of 128 isolated PVs. There were no instances of symptomatic PV stenosis during a mean follow-up of 245 ± 105 days. Conclusion: CT of the PVs allows identification of anatomic variants prior to catheter ablation procedures. Segmental ostial ablation results in a significant but small reduction in ostial diameter. Focal stenosis occurs infrequently and is attributable to delivery of radiofrequency energy within the PV. (J Cardiovasc Electrophysiol, Vol. 14, pp. 150-155, February 2003) [source] Irrigated-Tip Catheter Ablation of Pulmonary Veins for Treatment of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2002LAURENT MACLE M.D. Irrigated-Tip Catheter Ablation of PVs.Introduction: Catheter ablation of pulmonary veins (PV) for treatment of atrial fibrillation (AF) is limited by the disparate requirements of sufficient energy delivery to achieve PV isolation while avoiding PV stenosis. The aim of the present study was to evaluate the safety and efficacy of using an irrigated-tip catheter for systematic isolation of PV. Methods and Results: The study population consisted of 136 consecutive patients (109 men, mean age 52 ± 10 years) with symptomatic, drug-refractory paroxysmal (122) or persistent (14) AF. Cavotricuspid isthmus ablation and systematic radiofrequency isolation of all four PVs (guided by a circumferential mapping catheter) was performed in all patients with a protocol using an irrigated-tip catheter. PV diameter was assessed by selective angiography. The electrophysiologic endpoint of PV isolation was achieved in 100% of patients. Bidirectional cavotricuspid isthmus block was achieved in 99% of patients. Moderate PV stenosis (50% narrowing) was observed in one patient (0.7%) without clinical consequence. No other complications were observed. Reablation procedures were required in 67 patients (49%). After a mean follow-up of 8.8 ± 5.3 months, 81% of patients were free of AF clinical recurrence, including 66% not taking any antiarrhythmic drugs. Conclusion: Systematic radiofrequency ablation of PV using an irrigated-tip catheter in patients with atrial fibrillation allows complete isolation of all four PVs with a very low incidence of stenosis. [source] Catheter Ablation of Chronic Atrial Fibrillation Targeting the Reinitiating TriggersJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2000MICHEL HAÏSSAGUERRE M.D. Trigger Ablation in Chronic AF. Introduction: We assessed the mode of reinitiation of atrial fibrillation (AF) after cardioversion and the efficacy of ablating these foci of reinitiation in patients with chronic AF. Methods and Results: Fifteen patients, 7 with structural heart disease, underwent mapping and catheter ablation of drug-resistant AF documented to he persistent for 5 ± 4 months. In all patients, cardioversion was followed by documentation of P on T atrial ectopy and early recurrence, which allowed mapping of the reinitiating trigger or the source of ectopy. Radiofrequency (RF) ablation was performed at pulmonary vein (PV) ostia using a target temperature of 50°C and a power limit of 30 to 40 W, with the endpoint being interruption of all local muscle conduction. A total of 32 arrhythmogenic PVs and 2 atrial foci (left septum and left appendage) were identified: 1, 2, and 3 or 4 PVs in 5, 3, and 6 patients. RF applications at the ostial perimeter resulted in progressively increasing delay, followed by abolition of PV potentials in 8, but potentials persisted in 6. A single ablation session was performed in 7 patients and 8 underwent two or three sessions because of recurrence of AF; ablation was directed at the same source due to recovery of local PV potential or at a different PV. No PV stenosis was noted either acutely or at repeated follow-up angiograms. Nine patients (60%) were in stable sinus rhythm without antiarrhythmic drugs at follow-up of 11 ± 8 months. Anticoagulants were interrupted in 7 patients. Conclusion: PVs are the dominant triggers reinitiating chronic AF in this patient population. Elimination of PV potentials by ostial RF applications results in stable sinus rhythm in 60%. A larger group and longer follow-up are needed to investigate further the role of trigger ablation in curative therapy for chronic AF. [source] Vascular complications in living-related and deceased donation pediatric liver transplantation: Single center's experience from TurkeyPEDIATRIC TRANSPLANTATION, Issue 2 2007Aygen Yilmaz Abstract:, The aim of the study was to assess early and long-term incidence of venous complications, in both deceased donation (DD) and living-related (LR) liver transplantation (LT) in a pediatric population. Seventy-five liver transplants performed in 69 (39 boys, 30 girls) children at Ege University Hospital between 1997 and 2004 were prospectively monitored and reviewed. Age, sex, primary diagnosis, graft type, vascular complications and their management were evaluated. All patients received Doppler ultrasonographic examination both during operation and daily for the first three postoperative days and when necessary thereafter. The complications were classified as early and late presented. Thirty-three grafts (47.8%) were from DD and 36 (52.2%) were from LR donors. Recipients of DD were older than LR donors (mean age 10.5 ± 5.1 and 5.0 ± 0.7, respectively) (p < 0.05). Vascular complication occurrence was not statistically different between DDLT and LRLT recipients (p = 0.2), and between infants and children (p = 0.9). Overall, stenosis was more common than thrombosis. We observed hepatic artery (HA) thrombosis, in five of 75 (6.7%) transplants within 30 days post-transplant. Portal vein (PV) thrombosis and hepatic vein (HV) thrombosis were detected in six and one patients (8.7% and 1.3%), respectively. Six PV stenosis were identified (8.7%), while HA and HV-VC (vena cava) stenosis occurred in one and six patients (1.4% and 8.7%), respectively. All PV stenosis (6/33, 18.2%) and one PV aneurysm occurred in DDLT recipients while HV-VC stenosis were detected almost equally in LRLT and DDLT recipients (4/36 vs. 2/33). Except one, all PV stenosis were detected as a late complication and no intervention were needed. Stenosis of HV-VC was more common in girls (5/30 vs. 1/39) (p < 0.05) and the incidence was not different in DDLT and LRLT recipients (p = 0.8). In conclusion, overall incidences of thrombosis and stenosis formation after orthotopic liver transplantation (OLT) were 17.4% and 18.8%, respectively in our center. We suggest that in the cases with HA thrombosis manifested intra-operatively or within the early postoperative period, graft salvage was successful. Thrombosis of HA causes significant mortality. Thrombosis of PV was among the causes of mortality and morbidity. Stenosis of HV-VC could be managed by angioplasty and endovascular stenting with no significant effect to mortality. [source] Vascular Stents in the Management of Portal Venous Complications in Living Donor Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010Y.-F. Cheng To evaluate the efficacy of stent placement in the treatment of portal vein (PV) stenosis or occlusion in living donor liver transplant (LDLT) recipients, 468 LDLT records were reviewed. Sixteen (10 PV occlusions and 6 stenoses) recipients (age range, 8 months,59 years) were referred for possible interventional angioplasty (dilatation and/or stent) procedures. Stent placement was attempted in all. The approaches used were percutaneous transhepatic (n = 10), percutaneous transsplenic (n = 4), and intraoperative (n = 2). Technical success was achieved in 11 of 16 patients (68.8%). The sizes of the stents used varied from 7 mm to 10 mm in diameter. In the five unsuccessful patients, long-term complete occlusion of the PV with cavernous transformation precluded catherterization. The mean follow-up was 12 months (range, 3,24). The PV stent patency rate was 90.9% (10/11). Rethrombosis and occlusion of the stent and PV occurred in a single recipient who had a cryoperserved vascular graft to reconstruct the PV during the LDLT operation. PV occlusion of >1 year with cavernous transformation seemed to be a factor causing technical failure. In conclusion, early treatment of PV stenosis and occlusion by stenting is an effective treatment in LDLT. Percutaneous transhepatic and transsplenic, and intraoperative techniques are effective approaches depending on the situation. [source] | ||||||||||