PEPE II--a multicenter study with an end-point heparin-bonded expanded polytetrafluoroethylene vascular graft for above and below knee bypass surgery: determinants of patency.

AIM: The Propaten European Product Evaluation (PEPE II) study was a product evaluation intended to characterize the performance of the GORE PROPATEN vascular graft in above-knee (AK) and below-knee bypass (BK) surgery. METHODS: This prospective multicenter trial enrolled 142 patients with peripheral arterial disease. In 87 patients AK and in 52 patients BK bypasses (including 15 femorocrural) were implanted (67.6% males, 32.4% females). RESULTS: The one-year overall primary and secondary patency rates were 80% and 84.7%, respectively. Overall limb salvage rate at 12-months was 96.2%. The primary patency rate for AK bypasses was 82.7%, for BK femoro-popliteal bypasses 74.2% and for BK tibial-peroneal bypasses 79.4%. Secondary patency rates were 87.3%, 78.8% and 85.1%, respectively. Primary patency rates decreased depending on the number of patent run-off vessels (three 84.3%, two 80.8%, one 73.3%). Subgroup analysis showed that female patients had a significantly higher primary patency rate for BK bypasses (95.5% vs. 67.8%, P=0.037 ) compared to male patients. Subgroup analysis comparing patients younger and older than 70 years did not show a statistically significant difference in patency rates. Twenty-one patients underwent 42 reinterventions after bypass surgery. CONCLUSIONS: Present data show that the end-point heparin-bonded polytetrafluoroethylene graft yields patency rates comparable to those obtained with other graft material in above-knee locations. The encouraging results for BK bypasses suggests that this graft is an excellent option for small diameter vascular reconstructions when autologous vein is unavailable.

Laparoscopic partial posterior (Toupet) fundoplication improves esophageal bolus propagation on scintigraphy.

BACKGROUND: Impaired esophageal clearance is important in the pathogenesis of gastroesophageal reflux disease (GERD). It is unknown whether esophageal clearance improves following antireflux surgery. The aim of this study was to investigate the effect of laparoscopic Nissen fundoplication (NF), laparoscopic partial posterior (Toupet) fundoplication (PPF) or medical therapy on esophageal clearance. METHODS: This was a prospective nonrandomized crossover study. Sixty patients were evaluated with endoscopy, esophageal manometry, radionuclide scanning of esophageal emptying, and assessment of symptoms prior to surgery or medical therapy and 6 months after treatment. In 20 GERD patients with normal esophageal peristalsis an NF was performed, in 20 patients with impaired esophageal peristalsis a PPF was chosen, and 20 patients received proton-pump inhibitor (PPI) treatment. RESULTS: On endoscopy, esophagitis had resolved in all patients after surgery; two patients with medical therapy still had esophagitis. On manometry, a significant improvement of lower esophageal sphincter competence was seen in both surgical groups. LES relaxation was complete after PPF, but incomplete after NF. Esophageal peristalsis did not improve after medical therapy, was significantly improved after PPF, but had worsened after NF. On scintigraphic esophageal emptying for solid meals, there was no improvement after medical therapy but a significant improvement after PPF. A significant deterioration of esophageal emptying was observed after NF. There was a strong correlation between scintigraphic and manometric evaluation of peristalsis preoperatively (r(s) = -0.87, p < 0.05) and postoperatively (r(s) = -0.82, p < 0.05). There was no change in dysphagia after medical therapy and after NF but a significant improvement after PPF. Globus sensation was significantly improved after PPF but did not change after medical therapy or NF. Postprandial bloating and inability to belch were significantly more common after NF than after PPF. CONCLUSION: Laparoscopic partial posterior (Toupet) fundoplication can restore a preoperatively defective esophageal bolus propagation on scintigraphy with the same antireflux effect as the laparoscopic Nissen fundoplication, but with lower side-effects.

Electromagnetic versus fluoroscopic mapping of the inferior isthmus for ablation of typical atrial flutter: A prospective randomized study.

BACKGROUND: Radiofrequency catheter ablation within the tricuspid annulus-inferior caval vein isthmus can cure typical atrial flutter. The target for ablation, nonetheless, is relatively wide, and standard ablation procedures may require significant exposure to radiation. METHODS AND RESULTS: A total of 50 patients (mean age, 58+/-11 years) with typical atrial flutter were prospectively randomized to receive isthmus ablation using conventional fluoroscopy for catheter navigation (group I, n=24) or electromagnetic mapping (group II, n=26). Complete bidirectional isthmus block was verified with double potential mapping. If complete isthmus block could not be achieved after 20 radiofrequency pulses or 25 minutes of fluoroscopy, the patients were switched to the other group. Eight patients from group I (33%) but only 1 patient from group II (4%) were switched. Overall, complete isthmus block was achieved in 47 of 50 patients (94%). The overall fluoroscopy time, including the placement of the diagnostic catheters, was 22.0+/-6.3 minutes in group I and 3.9+/-1.5 minutes in group II (P:<0.0001). The fluoroscopy time needed for isthmus mapping was 17.7+/-6.5 minutes in group I and 0.2+/-0.3 minutes in group II (P:<0.0001). CONCLUSIONS: Electromagnetic mapping during the induction of linear lesions for the ablation of atrial flutter permitted a highly significant reduction in exposure to fluoroscopy while maintaining high efficacy, and it allowed the time required for fluoroscopy to be reduced to levels anticipated for diagnostic electrophysiological studies.

[Antitachycardia pacing for atrial tachyarrhythmias]. / Antitachykarde Stimulation während Episoden atrialer Tachyarrhythmien.

Overdrive pacing therapies are well established to treat patients with ventricular tachycardia. The main advantage is the quick and painless success with a high efficacy. Newer observations show that atrial arrhythmias with short cycle lengths (<200ms) can be terminated by painless overdrive pacing therapies as well. In the AT500 verification study and in the Jewel AF-trial, 30-60% of all treated atrial arrhythmias could be terminated by overdrive pacing. Nevertheless, these encouraging results need to be confirmed by additional randomized clinical trials. Especially the "hybrid" therapy (overdrive pacing in combination with an antiarrhythmic drug therapy) looks promising.

Endovascular repair or medical treatment of acute type B aortic dissection? A comparison.

INTRODUCTION: The aim of this retrospective study was to compare the outcome of thoracic endovascular aortic repair (TEVAR) to that of medical therapy in patients with acute type B aortic dissection (TBD). MATERIALS AND METHODS: From July 1996 to April 2008, 88 patients presenting with acute TBD underwent either TEVAR (group A, n=38) or medical therapy (group B, n=50). Indications for TEVAR were intractable pain, aortic branch compromise resulting in end-organ ischemia, rapid aortic dilatation and rupture. Follow-up was performed postinterventionally, at 3, 6 and 12 months and yearly thereafter and included clinical examinations and computed tomography (CT), as well as aortic diameter measurements and assessment of thrombosis. RESULTS: Mean follow-up was 33 months in group A and 36 months in group B. The overall mortality rate was 23.7% in group A and 24% in group B, where 4 patients died of late aortic rupture. In group A, complications included 9 endoleaks and 4 retrograde type A dissections, 3 patients were converted to open surgery and 2 needed secondary intervention. None of the patients developed paraplegia. In group B, 4 patients were converted to open surgery and 2 to TEVAR. The maximal aortic diameter increased in both groups. Regarding the extent of thrombosis, our analyses showed slightly better overall results after TEVAR, but they also showed a tendency towards approximation between the two groups during follow-up. CONCLUSION: TEVAR is a feasible treatment option in acute TBD. However, several serious complications may occur during and after TEVAR and it should therefore be reserved to patients with life-threatening symptoms.

[First diagnosis of Fallot tetralogy in a 74-year-old man]. / Erstdiagnose einer Fallot-Tetralogie bei einem 74-jährigen Mann Kasuistik über einen komplexen Fall einer Fallot-Tetralogie bei einem 74-jährigen Erwachsenen, der ohne chirurgische oder medizinische Behandlung überlebte.

Tetralogy of Fallot is the most common cyanotic cardiac malformation in late childhood and adult, occurring in approximately 0.25 of 1000 live births. Most patients undergo early surgical correction. Therefore, the natural history of this disease has been evaluated in only a few cases. We report a complex case of a tetralogy of Fallot, who reached the age of 74 years without surgical or medical treatment and who was transferred to our clinic after syncope due to ventricular tachycardia.

Pace-termination and pacing for prevention of atrial tachyarrhythmias: results from a multicenter study with an implantable device for atrial therapy.

INTRODUCTION: Patients with bradycardia requiring permanent pacing frequently suffer from additional atrial tachyarrhythmias (ATs). This study evaluated the safety and efficacy of atrial antitachycardia pacing (ATP) and the performance of pacing for AT prevention implemented into a new pacemaker. METHODS AND RESULTS: In patients with conventional indications for permanent pacing, an investigational DDDRP pacemaker (Medtronic AT500, model 7253) was implanted. The primary study objectives were to determine the safety of overall device functioning and its efficacy in terminating spontaneous AT. A secondary endpoint was to determine the reliability of AT detection. Pacemaker memory functions were used to analyze the impact of dedicated pacing algorithms on AT prevention. In 33 European and Canadian centers, 325 patients were enrolled (mean follow-up 2.3+/-1.3 months). Complication-free survival at 3 months was 88%. In 2,145 episodes stored with atrial electrograms, AT detection was confirmed in 97%. The algorithm for continuous overdrive pacing increased the percentage of atrial pacing to 97%. After ATP activation, 16,683 of 52,468 AT episodes were treated (120 patients). Of these, 8,903 episodes (53%) were terminated successfully by ATP. No proarrhythmic effect of preventive pacing or atrial ATP was observed. Preventive pacing algorithms increased the median percentage of atrial pacing from 62% to 97%. However, the number of AT/AF (atrial fibrillation) episodes (4.1 vs 4.1 per patient per day) and the time in AT/AF (13.7% vs 12.8%) was not significantly different before and after activation of preventive pacing. CONCLUSION: DDDRP pacing with a new system for AT therapy was safe and associated with successful pace-termination of AT in 53% of episodes. Preventive pacing and atrial ATP algorithms represent two new functions that can be implemented safely into pacemaker systems for nonpharmacologic treatment of ATs in patients requiring pacemaker therapy.

Intravital lectin perfusion analysis of vascular permeability in human micro- and macro- blood vessels.

We previously applied intravital lectin perfusion in mouse models to elucidate mechanisms underlying vascular permeability. The present work transfers this technique to human models, analysing vascular permeability in macro- and microvessels. Human vascular endothelial surface carbohydrate biochemistry differs significantly from its murine counterpart, lacking alpha-galactosyl epitopes and expressing the L-fucose moiety in the glycocalyx; the poly-N-lactosamine glycan backbone is common to all mammals. We examined extensively lectin binding specificities in sections and in vivo, and then applied the poly-N-lactosamine-specific lectin LEA and the L-fucose-specific lectin UEA-I in human intravital perfusions. Transendothelial transport differed in macrovessels and microvessels. In microvessels of adult human fat tissue, rectal wall and rectal carcinomas, slow transendothelial transport by vesicles was followed by significant retention at the subendothelial basement membrane; paracellular passage was not observed. Passage time exceeded 1 h. Thus we found barrier mechanisms resembling those we described previously in murine tissues. In both adult and fetal macrovessels, the vena saphena magna and the umbilical vein, respectively, rapid passage across the endothelial lining was observed, the tracer localising completely in the subendothelial tissues within 15 min; vesicular transport was more rapid than in microvessels, and retention at the subendothelial basement membrane briefer.

Incremental programming of atrial anti-tachycardia pacing therapies in bradycardia-indicated patients: effects on therapy efficacy and atrial tachyarrhythmia burden.

AIMS: Efficacy of pace-termination of atrial arrhythmias (ATP) may depend on atrial cycle length and regularity. Whether device programming of ATP therapies can improve ATP efficacy and alter atrial tachyarrhythmia burden is unknown. METHODS AND RESULTS: ATP efficacy was evaluated in 61 patients (39 males; 66 +/- 10 years) with a standard indication for pacing, 95% with a history of AT/AF. Each patient was implanted with a novel DDDRP pacemaker capable of delivering ATP therapy. ATP efficacy and AT/AF frequency and burden were compared within each patient during a period of nominal ATP programming (NP) followed by a period of aggressive incremental programming (IP). Adjusted ATP-termination efficacy was higher during IP than during NP (54.8% vs 37.9%, P < 0.05). No differences in AT/AF frequency (3.3 +/- 5.9 vs 3.2 +/- 6.9 day(-1)) or burden (18 +/- 28% vs 18 +/- 29%) were observed comparing NP with IP. The majority of episodes during both the NP (81%) and IP (77%) periods terminated within 10 min. Episodes lasting 24 h or more accounted for only 0.4% of the episodes in both groups. but accounted for 38% of the average burden during NP and 51% during IP. CONCLUSIONS: Device programming of ATP therapies can influence the number of treated episodes and the efficacy of ATP therapies although arrhythmic frequency and burden may not change. Total atrial arrhythmia burden is disproportionately influenced by long (>24 h) episodes.

Experience with a dual chamber implantable defibrillator.

An implantable defibrillator with dual chamber pacing may have advantages for pacing, sensing, and detection of brady- and tachyarrhythmias. This study evaluates the safety and performance of a dual chamber implantable cardioverter defibrillator that incorporates an algorithm to discriminate supraventricular from ventricular arrhythmias. The 300 patients in this study had the device implanted for the following indications: ventricular tachycardia (47%), sudden cardiac death survivorship (51%), and prophylactic implants (2%). Patients received dual chamber pacing for accepted bradyarrhythmic (51.7%) or investigational indications. During a mean follow-up period of 1.7 months a total of 1,092 arrhythmia episodes in 96 patients were fully documented in the device memory: 66 patients experienced a total of 796 ventricular tachyarrhythmia episodes and 42 experienced a total of 296 supraventricular episodes. The device appropriately detected 100% of sustained ventricular tachyarrhythmias while reducing the inappropriate detection of supraventricular tachyarrhythmias by 72% compared to single chamber rate only detection. The positive predictive value was 90.5% for ventricular tachyarrhythmia detection in episodes that exceeded the tachycardia detection rate. Adverse events observed in at least 2% of the patients were incisional pain (22%), inappropriate ventricular detection (7%), atrial lead dislodgement (4%), atrial oversensing/undersensing (3%), hematoma (3%), incessant ventricular tachyarrhythmia (2%), and pneumothorax (2%). There were 13 deaths, none of which were attributed to device failure. The Gem DR is safe and effective for the detection and treatment of ventricular tachyarrhythmias. The dual chamber detection algorithm appropriately recognized supraventricular tachycardia with rapid ventricular rates 72% of the time while maintaining 100% detection of sustained ventricular tachyarrhythmias.

[Clinical experiences with pectoral defibrillator implantation]. / Klinische Erfahrungen mit der pektoralen Defibrillatorimplantation.

UNLABELLED: The pectoral approach to implantation of cardioverter/defibrillators has the aim to further simplify the implantation of transvenous defibrillation systems. The PCD 7219 D/C is a device of the fourth generation which makes the pectoral implantation feasible due to a weight of 132 g, a size of 89 x 64 x 18 mm, a volume of 83 cm3 and a surface of 108 cm2. The use of the "active-can"-system (PCD 7219 C) requires the implantation of only one right ventricular lead. The PCD 7219 D/C was implanted in 75 patients with ventricular tachyarrhythmias, the follow-up period was 12 +/- 4 (1-24) months. Subpectoral implantation was feasible in 59 patients (79%), in 55 with a left pectoral, in 4 with a right pectoral approach due to previous left-sided operation or thrombosis of the left subclavian vein. Male sex (p < 0.005), body weight (p < 0.005) and body surface (p < 0.05) were predictors of pectoral implantation. In the 45 patients (60%) with a unipolar defibrillation system ("active can") the defibrillation threshold was significantly lower compared to those with a dual lead system (9.9 +/- 6.5, 2.5-24 Joule vs. 19 +/- 4.5, 6-24 Joule p < 0.0001). In one patient with pectoral and in one patient with abdominal implantation a dislodgement of the right ventricular lead was diagnosed and an operative revision was indicated. CONCLUSION: The down-sized implantable cardioverter/defibrillator PCD 7219 D/C makes the pectoral implantation feasible in the majority of patients. The use of the "active-can"-system requires the implantation of only one right ventricular lead with significantly lower defibrillation thresholds.