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Edward B Diethrich

Publications and source records attributed to Edward B Diethrich.

48 records · Page 3Linked to original sources
PubMed2002

Endoventricular transplantation of allogenic skeletal myoblasts in a porcine model of myocardial infarction.

PURPOSE: To assess the technical feasibility of percutaneous endoventricular injection of skeletal myoblasts into an infarcted porcine myocardium. METHODS: A skeletal muscle biopsy was obtained from a donor pig and processed for myoblast expansion in vitro. Myocardial infarction was induced in a host pig via fibrin coil placement in the left anterior descending artery. Four weeks later, electromechanical mapping of the left ventricle identified the infarction site, into which approximately 200 million allogenic cells obtained from the muscle biopsy were directly injected (0.1 mL/injection at 25 sites) from inside the ventricular cavity via a needle injection catheter inserted through the femoral artery. Ten days after transplantation, the injected heart was evaluated histologically for the presence of myoblasts. RESULTS: Electrocardiography, echocardiography, left ventricular angiography, and electromechanical mapping confirmed the myocardial infarction. During the cell transfer procedure, premature ventricular contractions confirmed needle placement in the endocardium. Histological evaluation of the host heart 10 days after cell transfer revealed living myoblasts and multinucleated myotubes in the infarcted region, indicating successful transplantation. CONCLUSIONS: Direct myoblast transplantation into infarcted porcine myocardium using an endoventricular injection was technically feasible. The results in this model show that transplanted myoblasts were able to survive for 10 days after transplantation.

Animals↗
PubMed2002

The AneuRx stent-graft since FDA approval: single-center experience of 230 cases.

PURPOSE: To compare a single-center experience with the AneuRx stent-graft system before and after FDA approval to results from the multicenter phase II clinical trial. METHODS: The medical records of 230 consecutive patients (218 men; mean age 74 years) undergoing AneuRx stent-graft implantation for abdominal aortic aneurysm (AAA) exclusion since September 1999 were reviewed to collect patient characteristics, aneurysm morphology, procedure variables, perioperative morbidity, mortality, and short-term outcome. These data were compared to the 30 patients treated at our institution during the AneuRx phase II clinical trial and to the overall multicenter trial data. Stent-graft difficulty was categorized from 1 (straight neck and access of appropriate size) to 4 (proximal neck <10 mm long or angulated >60 degrees and/or difficult access) based on aneurysm morphology. RESULTS: Data from the 30 patients enrolled in the phase II trial at our institution were comparable in terms of patient characteristics and procedure variables to patients treated after FDA approval and to the multicenter data. However, the proportion of cases involving aneurysms with a more complex morphology (levels 3 and 4) rose 22% after FDA approval, reflecting a change in referral patterns. Our postoperative endoleak and morbidity rates increased nonsignificantly with respect to our own phase II experience (17% versus 6%, 18% versus 11%, respectively); however, they were not significantly different from the multicenter data. Reintervention was performed in 15 of 38 endoleak cases, mostly type I. Only 5 (2.1%) cases had a persistent endoleak at the time of discharge. CONCLUSIONS: Since FDA approval of the AneuRx device, our endovascular practice has changed toward the management of increasingly more complex AAAs. Although we are attempting more challenging cases, we are able to maintain similarly high short-term success rates while offering stent-grafting to an increasing number of patients. These results suggest that more patients may be candidates for endoluminal graft placement than determined by the clinical trial selection criteria, provided that strict surveillance and long-term follow-up is maintained.

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PubMed2002

Crossing the limbs: a useful adjunct for successful deployment of the AneuRx stent-graft.

PURPOSE: To describe a technique for deploying an AneuRx stent-graft in an abdominal aortic aneurysm (AAA) with an acutely angled aortic neck. TECHNIQUE: In routine cases, the AneuRx stent-graft main body is positioned with the nose cone notch facing the contralateral side. In severely angulated aortic necks, however, the main body of the AneuRx stent-graft can be positioned with the nose cone notch and iliac limb gate facing the ipsilateral side; this dramatically reduces the acuity of the angle at the aortic neck and the iliac gate. This technique of "crossing the limbs" has been successfully used in 7 cases since FDA approval of the AneuRx device. CONCLUSIONS: Proximal neck angulation is an important factor for successful endovascular AAA repair. Crossing the graft limbs reduces the effect of neck angulation on the proximal main body and may decrease the stress upon the contralateral limb gate, which may avoid graft gate disconnection and endoleak.

Aortic Aneurysm, Abdominal↗
PubMed2002

Trends in endovascular surgery training.

PURPOSE: To gather vascular surgery fellows' opinions on various issues related to endovascular surgery (EVS) over a 2-year period and analyze the responses to identify trends in EVS training. METHODS: Vascular surgery fellows in 2 consecutive years were given a 2-page questionnaire inquiring about training protocols and local practice habits. Respondents included 64 vascular fellows from the academic year 1998-1999 (F98) and 52 vascular fellows from the academic year 1999-2000 (F99) (78% men in the entire population; mean age 34 years), representing a significant fraction of trainees in North America. Data from F98 and F99 were compared and analyzed. RESULTS: The majority (66%) of vascular surgery fellows were trained at university hospitals and performed EVS at the time of the survey: 83% in the F98 class and 92% in the F99 group (p=0.17). Utilization rates among the 9 interventions surveyed ranged from angiography (83%) and angioplasty (77%) to intravascular ultrasound (33%) and atherectomy (15%). Performance of endovascular grafting significantly increased among trainees (50% versus 81%, p<0.005), while atherectomy and angioscopy decreased. EVS performed in the operating room with portable imaging equipment decreased (67% versus 42%, p=0.02) as access to the radiology and cardiology suites increased. In most communities (63%), radiology specialists performed most of the EVS procedures, but the portion of communities where vascular surgery performed the majority of EVS procedures increased from 20% to 35% (p=0.10) from F98 to F99. Responders (90%) believed that EVS would become a major component of vascular surgery and comprise 30% of their future practice. The proportion of fellows who believed they were sufficiently trained in endovascular techniques increased from 30% to 50% (p=0.04), with the remainder willing to devote a short period (<3 months) for further training. CONCLUSIONS: The vast majority of vascular trainees perform EVS and believe that it will have an increasing role in their practice. Trends include increased endovascular grafting and performance of EVS by vascular surgeons in interventional suites.

Adult↗
PubMed2002

Stenting for proximal para-anastomotic stenosis of an infrarenal aortic bypass graft.

We present a case in which endovascular stenting was used for recurrent proximal para-anastomotic stenosis 11 years after aorto-bi-iliac bypass grafting for severe aorto-iliac occlusive disease. A 55-year-old woman presented with worsening bilateral hip and buttock claudication. At presentation, her resting ankle-brachial indices were 0.87 bilaterally and decreased to 0.39 on the right and 0.40 on the left with exercise. Aortography demonstrated a proximal para-anastomotic aortic graft stenosis without distal outflow obstruction, patent superficial femoral arteries, and good triple-vessel runoff bilaterally The stenosis was dilated with a 9- x 4-cm OPTA balloon angioplasty catheter. A Palmaz stent (P424, Cordis) was mounted on a 10- x 4-cm OPTA balloon catheter and deployed across the proximal stenosis. Completion arteriography confirmed adequate placement and reduction in the degree of stenosis. There was no pressure gradient across the proximal anastomosis. At our patient's 1-week follow-up visit, her resting ankle-brachial indices were both greater than 1.0 and her exercise ankle-brachial indices were 1.0 bilaterally She remained asymptomatic at 13 months. Most late sequelae of aortic graft surgery involve the distal anastomosis and are resolved surgically without complicated techniques. However, revision at the proximal anastomosis involves the aorta directly and therefore requires open abdominal dissection and aortic cross-clamping. Percutaneous aortic stenting for primary aortoiliac disease has been shown to reduce operative time, cost, and hospital stays, to improve patency and to be durable. Our clinical experience with aortic stenting for primary disease led us to consider this procedure for recurrent proximal stenosis.

Aorta, Abdominal↗
PubMed2002

A prospective study of ultrasound scan-guided thrombin injection of femoral pseudoaneurysm: a trend toward minimal medication.

BACKGROUND: Catheterizations and endovascular procedures in which the femoral artery is cannulated are sometimes complicated by iatrogenic pseudoaneuryms. Surgical repair of pseudoaneurysms was the treatment of choice until 1991 when compression was used in those that were small. A less uncomfortable technique involving the ultrasound scan-guided injection of thrombin (UGTI) has been used more recently. The purpose of this study was to prospectively evaluate the effectiveness of ultrasound scan-guided thrombin injection (UGTI) as a treatment of iatrogenic femoral pseudoaneurysms. METHODS: From December 1998 to December 2000, 3734 femoral artery catheterizations were performed, and from those, 32 consecutive patients with 33 femoral pseudoaneurysms (0.88%) of less than 8 cm were prospectively enrolled for UGTI. With sterile technique, a 21-gauge or 22-gauge spinal needle was used to access the pseudoaneurysm and thrombin (100 to 6000 international units [IU]) was slowly injected until thrombosis occurred. RESULTS: The initial success rate was 100%. Thirty-one cases (93.9%) remained successfully thrombosed with a single injection at day 30. Recurrence of two pseudoaneurysms (6.1%) was seen at day 1 and day 8. One patient had groin cellulitis develop, and the other had a bleed into the thigh after discharge; both were treated with open surgical repair. Fifteen patients underwent UGTI on an outpatient basis with 100% successful ablation. More than half of the patients were on an inpatient basis (53.1%). Hospital stay was 1 to 9 days, with 88.2% of the patients released on day 1 or 2. However, two patients had a prolonged stay: one from open repair (day 9) and the other from a gastrointestinal bleed (day 8). Pseudoaneurysms ranged from 1.7 to 7.5 cm and lasted 1 to 17 days before UGTI. Twenty-one of the patients (65.7%) continued undergoing anticoagulant therapy at the time of injection. Ten of the last 11 cases needed less than 800 IU, and nearly half of the pseudoaneurysms (49%) successfully thrombosed with less than 600 IU. No procedural complications or mortality were noted. No statistical significance was found between occurrence of the pseudoaneurysm and sheath size (with chi(2) test, P value =.05) or between the size of the pseudoaneurysm and successful thrombosis (with chi(2) test: degrees of freedom, 6 - 1 = 5; P value =.227426). A mean follow-up period of 11.8 months was documented (range, 71 to 24 months). Seven patients were lost to follow-up at less than 30 days. CONCLUSION: Percutaneous thrombin injection of iatrogenic pseudoaneurysms is an effective treatment. Not only is it minimally painful, but it can be done as an outpatient procedure and anticoagulation therapy does not hinder the success. Minimal thrombin seems necessary to successfully treat pseudoaneurysms that may further limit procedure-related complications.

Adult↗
PubMedDate not supplied

Thoracic aortic dissections: unpredictable lesions that may be treated using endovascular techniques.

Advances in endoluminal technology have enabled interventionists to treat a variety of pathologies that traditionally would require open surgery. Although excluding descending thoracic aortic aneurysms seems feasible, thoracic aortic dissection and its complications are an area in which the appropriateness of endovascular therapy has yet to be defined. Five case reports are presented, each with varying pathologies associated with type III dissections. The follow-up of the cases ranged from 6 to 18 months with a mean of 12.2 months. The endovascular approach and the technical aspect of the intervention have been emphasized in each case.

Adult↗
PubMedDate not supplied

Endografting of the thoracic aorta:.

BACKGROUND: Thoracic aortic dissections, ruptures, fistulae, and aneurysms pose a unique surgical challenge. Traditional repair of thoracic aortic aneurysms involves thoracotomy with graft interposition. Despite advances in perioperative care and both total and partial cardiopulmonary bypass, conventional surgery carries a significant morbidity and mortality. Principal complications include bleeding, paraplegia, stroke, cardiac events, pulmonary insufficiency, and renal failure. Recent enthusiasm for innovative endovascular therapies to treat aortic disease has spurred many centers to investigate endoluminal grafting of the thoracic aorta. Early reports on endovascular repair using custom made "first generation devices" demonstrated the technique to be feasible with a mortality and morbidity comparable to open repair. METHODS AND RESULTS: From February 2000 to February 2001, endovascular stent graft repair of the thoracic aorta was performed in 46 patients (mean age 70; 29 male and 17 female) using the Gore Excluder. Twenty-three patients (50%) had atherosclerotic aneurysms, fourteen patients (30%) had dissections, three patients (7%) had aortobronochial fistulas, three patients (7%) had pseudoaneurysms, two patients (4%) had traumatic ruptures, and one patient (2%) had a ruptured aortic ulcer. Patient characteristics, procedural variables, outcomes, and complications were recorded. All patients were followed with chest CT scans at 1, 3, 6, and 12 months. Mean follow up was 9 months ranging from 1 to 15 months. All procedures were technically successful. There were no conversions. Average duration of the procedure was 120 minutes. Average length of stay was 6 days, but most patients left the hospital within 4 days (64%) after endoluminal grafting. Overall morbidity was 23%. Two patients (4%) had endoleaks that required a second procedure for successful repair. Two patients (4%) died in the immediate postoperative period. There were no cases of paraplegia. At follow-up, one patient had an endoleak found the day after the procedure and another patient had an endoleak 6 moths post procedure. Both were treated successfully with additional stent grafts. There were no cases of migration. One patient died of a myocardial infarction 6 months after graft placement. The Gore Excluder device was voluntarily recalled on February 26, 2001. Therefore, from June 2000 to January 2001, 37 patients underwent endovascular stent graft repair of the thoracic aorta for various disease entities using our customized thoracic graft (Endomed). Twenty-seven patients (73%) had aneurysms, six (16%) had dissections, two (5%) had pseudoaneurysms, one (2%) had a traumatic transection, and one patient (2%) had an embolizing ulcer. Patients were followed with CT scans at 1, 3, 6, and 12 months. All procedures were technically successful. There were no conversions. The average age was 68 years.(17-87). And the male and female ratio was 24/13. One patient died in the operating room from iliac rupture and one died from embolization/stroke in the immediate postoperative period. Two patients died within 30 days from comorbid factors. The total 30-day mortality was 10%. Two patients had endoleaks. One returned to the operating room and needed an additional cuff. The other had a small leak in a proximal dissection that is being followed. There were no cases of paraplegia. CONCLUSION: Thoracic endoluminal grafting is a safe and feasible alternative to open graft repair and can be performed successfully with good results. Early data suggest that an endoluminal approach to these disease entities maybe favorable to open resection and graft replacement. Technical details of Endoluminal stent grafting of the thoracic aorta for different disease entities have been discussed at length.

Adult↗
PubMedDate not supplied

Pseudoaneurysm of the aortic arch after aortosubclavian bypass treated with endoluminal stent grafting--a case report.

This paper describes a case of aortic arch pseudoaneurysm treated with stent graft 2 years after aortosubclavian bypass repair of a subclavian artery aneurysm. An 84-year-old man presented with back pain. Two years before, he had had a left subclavian artery aneurysm repaired with aortosubclavian bypass. Upon examination by computed tomography (CT) scan and angiography he was found to have a bovine arch configuration, a 7-centimeter pseudoaneurysm arising from the stump f the native subclavian artery, a patent aortosubclavian bypass, and a left hemothorax. A 37 mm by 10 mm Gore Excluder thoracic graft was introduced into the right femoral artery cutdown and deployed across the arch, excluding the pseudoaneurysm and preserving the brachiocephalic vessels. Follow up CT scan at 1 year shows exclusion of the pseudoaneurysm. The patient continues to do well 1 year after implantation without evidence of endoleak. In the presence of unusual anatomical characteristics, endoluminal stent graft repair can be successfully performed across the aortic arch.

Aged↗