Teflon Felt Research Articles

Mitral valve replacement with the pulmonary autograft: Midterm results

We performed mitral valve replacement with a pulmonary autograft using the technique described by us earlier and present the results. Between August 2000 and July 2007, 19 patients (16 male patients; age, 30-58 years) with isolated calcific mitral stenosis (n = 16) or mixed mitral stenosis and regurgitation (n = 3) underwent mitral valve replacement with a pulmonary autograft. Sixteen patients were in New York Heart Association class III and 3 were in New York Heart Association class IV preoperatively. Eight patients were in atrial fibrillation. The autograft implantation was achieved by using a scalloped stent of polytetrafluoroethylene felt for external support of the autograft. No anticoagulants were prescribed. There were 3 early deaths, one each caused by ventricular dysfunction, ventricular arrhythmias, and autograft dehiscence requiring early reoperation. Follow-up of survivors ranged from 34 to 99 months (mean, 71.9 +/- 18.2 months; median, 75 months). The mean valve area was 2.96 +/- 0.9 cm(2) (range, 2.2-4.3 cm(2)). Fourteen survivors are in New York Heart Association class I, and 2 are in NYHA class II; 4 continue to be in atrial fibrillation. Follow-up echocardiograms (n = 16), magnetic resonance imaging (n = 6), and cardiac catheterization (n = 4) have demonstrated no significant autograft and pulmonary homograft dysfunction. There were no late deaths or reoperations or thromboembolic complications. Mitral valve replacement with a pulmonary autograft, a complex operation, can be performed in selected patients with acceptable results. The use of our technique of autograft implantation offers several advantages and avoids exposure of the scaffold to the bloodstream.

Virtual Angioscopy and 3-Dimensional Navigation Findings of the Aortic Arch After Vascular Surgery

The anatomy of the aortic arch is variable, and its detailed analysis on computed tomography (CT) scan may be difficult. Indeed, its curvature, angulations, length of horizontal portion, and origin of supra-aortic trunks (SAT) may vary among individuals. Furthermore, drastic modifications of the patient’s anatomy may be observed after open or endovascular surgery and in case of congenital abnormalities. The 3-dimensional (3D) nature of the aortic arch is then difficult to assess on an axial plane. Current workstations have permitted the reconstruction in 2 dimensions of the aortic arch, and the volume-rendering technique or shaded surface display gives an external analysis of the structures. Virtual angioscopy, first described in 2001,1 allows the realization of an endoluminal navigation in 3 dimensions. It is based on the notion of active vision, in which only visual perception drives the motion of the virtual angioscope.2 The navigation mode allows manual analysis of the elements of the aortic arch under different viewing angles and dynamic localization of abnormalities in relation to SAT with high precision and better understanding. Here are examples of patients having undergone an aortic arch procedure and for whom the fly-through with the help of virtual angioscopy has permitted better understanding of abnormalities of the aortic arch. A 64 Light Speed VCT multidetector-row CT was used (General Electric Medical Systems, Milwaukee, Wis), allowing maximal intensity projection and maximal projection-rendering imaging, as well as 3D rendering of images. Images were analyzed on a dedicated platform (Advantage Windows 4.2, General Electric Medical …

MICROVASCULAR DECOMPRESSION IN HEMIFACIAL SPASM RESULTING FROM A CEREBELLOPONTINE ANGLE LIPOMA

Hemifacial spasm caused by a cerebellopontine angle lipoma is extremely rare. We describe a patient with left-sided hemifacial spasm caused by vascular compression of the facial and vestibulocochlear cranial nerves by the anteroinferior cerebellar artery embedded within a cerebellopontine angle lipoma. A 77-year-old man presented with a 10-year history of left-sided facial spasms that progressively worsened over time and significantly interfered with his ability to read, drive, and interact in social situations. Neurological examination showed obvious left hemifacial spasm, including orbicularis oculi and levator labii muscles. Magnetic resonance imaging revealed characteristic abnormal signal within the cerebellopontine angle cistern that was consistent with lipoma abutting the anteroinferior cerebellar artery. Surgical exploration with standard retrosigmoid craniectomy and subarachnoid dissection of the cerebellopontine angle was performed. The offending anteroinferior cerebellar artery branch was dissected away from the VIIth and VIIIth cranial nerves. Teflon felt was interposed between the artery and nerves after the artery was dissected off the surface of the lipoma. Electrophysiological monitoring showed resolution of the abnormal hemifacial spasm response during the procedure. No attempt was made to resect the lipoma, given the risk to injury of the brainstem and perforating blood vessels. Postoperatively, the patient's symptoms were completely resolved. This case demonstrates that relief of the vascular compression, when present, of the VIIth cranial nerve is sufficient for resolution of hemifacial spasm symptoms, even when associated with nearby, benign lesions.

Technical note for microvascular decompression at trigeminal neuralgia caused by its’ compression by vertebral artery

The technique of microvascular decompression at trigeminal neuralgia caused by nerve’s flattening against the tentorium is described. The original method is used to make a space between the tentorium and tortuous artery — inserting a piece of non-scattered double teflon felt against artery and tentorium.

Hemolytic Anemia After Operation for Aortic Dissection Using Teflon Felt Strips

We report three cases of hemolytic anemia caused by anastomotic stenosis after surgical treatment for aortic dissection in which internal and external Teflon (DuPont, Wilmington, DE) felt strips were used for reinforcement of the aortic stump. To detect this complication, laboratory findings typical of red cell fragmentation syndrome as well as appropriate imaging modalities are necessary. As a precaution, it is necessary to be meticulous when stitching the internal felt strip.

A modified infarct exclusion technique: Triple-patch technique for postinfarction ventricular septal perforation

Postinfarction ventricular septal perforation (VSP) remains an important complication of myocardial infarction. The prevalence is approximately 1% to 2% among patients withacutemyocardialinfarction,anditisoftenfatalunless surgical treatment is performed. Despite numerous improvements in surgical technique, the mortality remains about 19% to 40%. 1 Perioperative low-output syndrome and residual shunt are associated with a poor outcome. We operated on 4 patients with our simple technique that minimizes residual shunting. Materials and Methods OPERATIVE TECHNIQUE. Cardiopulmonary bypass was established, and myocardial revascularization if necessary was performed on the beating heart before repair of the VSP. The heart was then arrested with a cardioplegic solution, and repair was done through a longitudinal left ventriculotomy in the infarcted area, about 1 to 2 cm away from the left anterior descending coronary artery. First, a tailored small bovine pericardial patch was used to close the VSP directly with a running 3-0 polypropylene suture. Then two bovine pericardial patches were cut into rectangular shapes. One pericardial patch was sutured to the noninfarcted endocardium around the ventricular septal side, and the other patch was sutured to the noninfarcted endocardium of the anterolateral ventricular wall, both with running 3-0 polypropylene sutures. These two patches were then cut and sewn to determine the ideal size and shape of the pouch fitting the left ventricular cavity to make an infarct exclusion. After the VSP patch and endoventricular pouch were sutured, fibrin glue was applied to fill the cavity between the patches. The ventriculotomy was closed in two layers with two polytetrafluoroethylene felt strips and 2-0 polypropylene sutures (Figure 1). PATIENTS. Between 1996 and 2006, a total of 10 patients underwent VSP repair. Through 2003, we performed VSP repair by the David‐Komeda method in 6 patients. Since 2004, the new triplepatch technique has been used for all patients. STATISTICAL ANALYSIS. Preoperative and postoperative variables were compared between the two operative groups with the Mann‐Whitney U test.

One-Stage Repair of Extensive Thoracic Aortic Aneurysm Using the Arch-First Technique and Bilateral Anterior Thoracotomy

One-Stage Repair of Extensive Thoracic Aortic Aneurysm Using the Arch-First Technique and Bilateral Anterior Thoracotomy

Proximal Suture Line Support in Open Abdominal Aortic Aneurysm Repair: A Comparative Study

The aim of this study was to determine whether the collar graft (standard dacron graft with a customized flexible collar attached to the proximal rim) decreased anastomotic bleeding and the overall clamp time. Prospective randomised single center study. Between November 2003 and January 2006, 21 patients were treated with a collar graft and 19 with a standard dacron graft. Routine endoaneurysmorraphy was used. Only infra-renal aneurysms between 5.5cm and 6.5cm were included. Aneurysms were diagnosed by CT scans. The total number of bleeding points, the total clamp time, and the number of teflon felt pledgets, was determined. The total number of bleeding points; the number of aortic re-clamps and total clamp time (minutes) per patient were all significantly lower in the collar graft group (1.2 versus 2, p<0.04; 0.5 versus 2.0, p<0.001; 13.6 versus 20.1, p<0.003 respectively). The number of teflon felt pledgets and new sutures used was significantly lower in the collar graft group (p<0.001 and p<0.003 respectively). The collar graft resulted in fewer anastomotic bleeding points and a shorter clamp time.

Teflon Granuloma of the Skull Base: A Complication of Endonasal Brain Surgery

Teflon granuloma is an inflammatory giant-cell foreign-body reaction to polytetrafluoroethylene fibers or injection. Tissue augmentation with Teflon has dramatically declined over the past two decades because of its implication in granuloma formation. Nevertheless, Teflon felt is still commonly used in neurosurgical dissection and microvascular decompression. We report a patient with a Teflon granuloma of the skull base discovered 1.5 years after endonasal resection of an olfactory groove meningioma. The case highlights the clinical and radiographic diagnosis as well as the management of this unusual finding.

Recurrent trigeminal neuralgia secondary to Teflon felt

The authors present a case of a 45-year-old man with recurrent trigeminal neuralgia twelve years after microvascular decompression. The patient underwent surgical reexploration of the trigeminal nerve. A piece of hardened Teflon felt was found piercing a hole through the trigeminal nerve. No other compression of the nerve was found. Removal of the Teflon felt resolved the neuralgia. To the authors knowledge this is the first report of recurrent trigeminal neuralgia due to such a mechanism. This case emphasises the need for further improvement of the surgical technique for microvascular decompression of the trigeminal neuralgia.

Use of fenestrated aneurysm clips in microvascular decompression surgery

/The standard techniques of microvascular decompression (MVD) surgery in which implant materials such as shredded Teflon felt are used may be inadequate in some complex cases. The authors evaluated the use of fenestrated aneurysm clips to maintain transposition of culprit vessels in patients with trigeminal neuralgia (TN) and hemifacial spasm (HFS). The authors conducted a retrospective review of MVD operations in which the culprit vessel was transposed and then maintained in position with a fenestrated aneurysm clip secured in position by suturing it to the dura mater. Among a consecutive series of more than 450 MVD surgeries, the fenestrated aneurysm clip sling was used in eight of the last 100 cases: six for HFS and two for TN. The follow-up period ranged from 1 to 13 months, and complete symptom resolution was noted in seven of the eight patients. No patient exhibited evidence of any surgical complications. This approach can be safely performed in complicated MVD cases such as reoperations and transpositions of long ectatic arteries. To the best of the authors' knowledge this is the first report in which the use of fenestrated aneurysm clips in MVD surgery is described.

Panel Discussion: Session I—Ascending Aorta

Panel Discussion: Session I—Ascending Aorta

Patent ductus arteriosus in adults: Surgical experience in Ivory-Coast

Patent ductus arteriosus surgery is well documented. Hospital Mortality has reduced to almost 0%. Yet, with adults, this surgical cure is likely to be difficult and require some technical skills A retrospective study of surgical procedures and results after surgery of patent ductus arteriosus (PDA) in adults. Since 1978 to 2000 we have reported 16 operated cases. The average age was 22.5 years. There was female predominance with a sex ratio of 2.3/1. All patent ductus arteriosus had been confirmed by two dimensional echocardiography (2D echocardiography) and cardiac catheterization. All hemodynamic types of Nadas classification were observed. Double or triple ligation supported on Teflon felt was the most frequent technique used (69%). This technique gave good results in view of the absence of hospital mortality and only 1 case of recanalisation after a long follow up of all patients from 1 - 7 years (mean 5 years). Double or triple ligation on Teflon felt according to Wright technique is a good technique.

Teflon Felt Wrapping Repair for Coronary Perforation After Failed Angioplasty

Acute type III perforation caused by failed angioplasty is a lethal complication that often requires emergency operation. However, the presence of multiple rigid stents beneath the subepicardial hematoma disturbs optimal revascularization and hemostasis. Teflon felt (Meadox Medical Inc, Oakland, NJ) wrapping repair is a simple salvage technique that allows stable hemostasis and the rescue of the entire blood flow of the coronary artery. This procedure was successfully performed with type III perforation of the left anterior descending coronary artery on 2 patients subjected to multiple stenting.

External Reshaping of the Left Ventricle in Off-Pump Surgery

: Dyskinetic areas of the lateral and inferior left ventricular (LV) wall are frequently encountered in patients with coronary artery disease. In clinical practice, all of the techniques described for the restoration of shape and function of the LV require cardiopulmonary bypass. A new technique of LV external reshaping that aims to obtain a near-normal ventricular conical shape is described. This technique is performed during an off-pump coronary artery bypass graft (CABG) operation. It is used mainly on the inferior and lateral walls of the ventricle, but also on the anterolateral wall when warranted. This technique can be considered an alternative to classic aneurysmectomy in high-risk cases. : All patients underwent total arterial revascularization without aortic manipulation. Intraoperative transesophageal echocardiography was used in all cases to define the dilated akinetic/dyskinetic area. This area was effectively plicated using interrupted mattress sutures reinforced with Teflon felt or pericardial strips. This technique allows near normalization of the geometry of the ventricle and LV end-diastolic volume reduction. In cases of preexisting mitral regurgitation (MR), a reduction of the MR was observed after lateral wall restoration. From September 2002 to April 2005, the external reshaping technique was applied on 56 cases among 949 off-pump CABG cases (5.9%). A detailed transthoracic echocardiogram was obtained preoperatively. The mean ejection fraction of all enrolled patients was 31.2 ± 7%. The location of the plication was: lateral wall in 22, inferior wall in 16, and anterolateral wall in 18. The average number of coronary anastomoses was 2.6. Twelve patients were found to have 2-3+ MR. All patients were followed up during a period of 35 months. : One patient died due to severe right ventricular dysfunction. Seven patients developed atrial fibrillation, and one had ventricular tachycardia. During the follow-up period, we observed a reduction of left ventricular end-diastolic diameter and a parallel augmentation of ejection fraction (mean 42.2 ± 4%). The ventricular cavity's architecture was normalized. Among the 12 patients with MR, an improvement of regurgitation was noted in 10 (from 2-3+ to 1-2+). One patient died during the follow-up period, and 1 patient required reoperation due to persistent severe MR. : The external reshaping of the LV during beating heart surgery is technically feasible, has promising results, and can be performed without major complications.

The wrapping method using biodegradable felt strips has a preventive effect on the thinning of the aortic wall: Experimental study in the canine aorta

Wrapping methods have been widely used to reinforce the anastomotic site in vascular surgery; however, postoperative changes in the aortic wall wrapped by nonbiodegradable felt have not been well characterized. The purposes of this investigation are to elucidate the sequelae of wrapping with nonbiodegradable felt on the aortic wall and to modify those changes by using biodegradable felt with or without basic fibroblast growth factor (bFGF). The descending thoracic aortas of 15 beagles were wrapped with three different materials: nonbiodegradable polytetrafluoroethylene (PTFE) felt, biodegradable polyglycol acid (PGA) material, and PGA with 100 microg bFGF (n = 5 in each group). The descending thoracic aorta was resected after 3 months. The thickness of the aortic wall, vessel density in the media and the adventitia, and the wall strength were assessed. Untreated native aortic wall served as a normal control. The thickness of the media of the PTFE group was lower than that of the PGA + bFGF group (66% +/- 5% vs 85% +/- 6% of control, P < .05). The adventitia-media ratio in the PTFE group decreased compared with controls (59.1% of normal, P < 0.05), whereas those in the PGA and PGA + bFGF groups increased (172.1% and 189.6% of normal, respectively, P < .01). The collagen-smooth muscle ratio in the media was higher in the PTFE group than in the controls (0.14 +/- 0.02 vs 0.07 +/- 0.01, P < .01). The number of vessels in the adventitia was higher in the PGA + bFGF group than those in PTFE or PGA groups (29.6 +/- 2.5/mm2 vs 6.4 +/- 0.8/mm2, 19.0 +/- 1.1/mm2, P < .01). The PGA + bFGF group demonstrated larger failure force than the PTFE group (4.0 +/- 0.3 kgf vs 1.6 +/- 0.3 kgf, P < .01). The failure stress in the PGA and PGA + bFGF groups was larger than that in PTFE group (PTFE:PGA + bFGF = 5.3 +/- 0.9 x10(2) kPa:11.7 +/- 1.7 x 10(2) kPa, P < .01; PTFE:PGA = 5.3 +/- 0.9 x 10(2) kPa:11.2 +/- 1.2 x 10(2) kPa, P < .05). The aortic wall wrapped with nonbiodegradable PTFE felt showed a reduced thickness and diminished vessels in the adventitia. Biodegradable felt (PGA), with or without bFGF, modified these histologic changes. The vessel-rich thickened adventitia, after wrapping by PGA with bFGF, was associated with increased aortic wall strength. This investigation was conducted in an attempt to elucidate mechanisms underlying the occurrence of late postoperative false aneurysm after aortic surgery. We hypothesized that sustaining compression of the aorta by the felt strip may cause structural derangement and local ischemia on the aortic wall. We used a simple wrapping of the aorta with a felt strip rather than a felt strip at anastomotic sites to simplify the experimental model and to exclude confounding factors brought by technical inconsistency on the surgical anastomosis. We further attempted to find a clue for preventing adverse effects of wrapping with a conventional felt strip. Practically, we pursued a possible application of a biodegradable felt strip to aortic wrapping in our experimental model before we proceed in a clinical application of the new material.

Adventitial inversion technique without the aid of biologic glue or Teflon buttress for acute type A aortic dissection

This study was performed to evaluate the clinical usefulness of the adventitial inversion technique in acute type A aortic dissection, with special attention to the impact of this procedure on the postoperative status of false lumen evaluated by computed tomographic scan. From March 2001 to November 2004, 18 consecutive patients underwent emergent surgery for acute type A aortic dissection. Supracoronary graft replacement was performed in all the patients (ascending aorta/hemiarch replacement: 13/18=72%, total arch replacement: 5/18=28%). The adventitial inversion technique was used for both the proximal and the distal stump constructions of the dissected aortic wall without the aid of Teflon felt or biologic glue. Aortic regurgitation was treated with resuspension of the aortic commissures. There were two hospital deaths and the overall hospital mortality rate was 11.1%. The mean postoperative blood loss was 635+/-214 ml and no reexploration was required in any of the patients. Postoperative computed tomography showed closure of the false lumen in aortic root, aortic arch, and proximal descending thoracic aorta in all of the surviving patients. Postoperative echocardiography demonstrated no aortic regurgitation in any of the patients. Two patients died late postoperatively from unrelated causes to aortic dissection. The remaining 14 patients are doing well without a second-stage operation for aortic root or distal aortic lesions during the follow-up period of 7-51 months (mean: 28+/-14 months). The adventitial inversion technique provides an excellent immediate hemostasis and facilitates thrombotic closure of the proximal and the distal false lumen in the treatment for acute type A aortic dissection.

MICROVASCULAR DECOMPRESSION TREATMENT OF TRIGEMINAL NEURALGIA

Aim: To evaluated 20 trigeminal neuralgia patients who were resistant to medical treatments underwent surgery between years 1997-2000 in our clinic. Methods: The surgical procedure was microvascular decompression with lateral suboccipital approach. Surgical results and complications were compared to other techniques with review of the literature. Twenty patients with a mean age of 55 underwent surgery, 12(12%) of them were female and 8(40%) of them were male. Results: Pain was on the left side in 11(55%) and on the right side in 9(45%) patients. Diagnosis of the trigeminal neuralgia was based on the followings: Response to carbamazepine treatment, analysis of the pain with a detailed history, neurological examination and radiological evaluation. 8 patients had a history of hypertension and none of the patients in entire group had a known diagnosis of multiple sclerosis. Pain was experienced mostly on V1,V2 and V2,V3. Cranial magnetic resonance imaging (MRI) was performed to all patients. The etiological factors were estimated as idiopathic or vascular compression in 19, and epidermoid tumor in 1 patient. Patients were operated in semisitting position with a mayfield and lateral suboccipital surgical approach was chosen. Microvascular decompression was applied in 15 patients by using teflon felt and in 4 patients by using goretex. The epidermoid tumor was evacuated in one patient. Superior cerebellar artery was found as the commonest artery that caused entry zone nerve compression. During the postoperative period of 4 months to 3.5 years the 15 (% 75) of the patients were pain-free without any medical treatment; 2(% 10) patients were pain-free on welltolerated medication and mild-pain without medication; 2(% 10) patients had no pain relief; and 1(% 5) patient was pain-free after the operation for more than 1 month followed by the recurrence of pain requiring medical or surgical therapy. Microvascular decompression technique has been suggested superior to alternative methods for its safety and efficacy without recurrence. Conclusion: Our results support the notion that microvascular decompression is the surgical treatment of choice for patients with trigeminal neuralgia who are younger than 70 year-old, have no risk for anesthesia and who are resistant to medical treatments.

Pitfalls of sutureless repair of a blow-out type left ventricular free wall rupture

A 55-year-old man was admitted for acute myocardial infarction. Cardiac catheterization revealed total occlusion of the left circumflex artery. During catheterization, he suffered cardiogenic shock. Percutaneous cardiopulmonary support was established, and the patient was transferred to the operating room. A blow-out left ventricular free wall rupture (LVFWR) with an epicardial tear, 1 mm in diameter, was found, and sutureless repair with a collagen hemostat (TachoComb) was performed. However, on postoperative day 7, echocardiography revealed an echo-free space resembling a pseudoaneurysm. A second operation was performed immediately for impending re-rupture. An epicardial tear, 2 x 10 mm in diameter, was found at the previous bleeding point where hemostasis had been achieved with only one sheet of TachoComb. The defect was closed with mattress sutures buttressed with Teflon felt. We conclude that even if the risk of re-rupture is low, sutureless repair with a collagen hemostat alone should be avoided in treating blow-out LVFWR.

Bench Repair of Donor Aortic Valve With Minimal Access Orthotopic Heart Transplantation

While the number of people waiting heart transplantation increases, the number of organ donors decreases. This shrinking donor pool has prompted reassessment of donor selection for heart transplantation. Bench repair of a donor aortic valve was performed before minimal access orthotopic heart transplantation. Aortic insufficiency in the structurally normal tricuspid aortic valve was due to annular dilatation and was corrected with subcommissural annular plication. The postoperative period was uneventful. Follow-up at 4.5 years showed good results and no evidence of aortic regurgitation.