Technical Strategies to Expand Stent-Graft Applicability in the Aortic Arch and Proximal Descending Thoracic Aorta

The endovascular repair of thoracic aortic pathology is on an evolutionary threshold, as advancing technologies and techniques combine to offer the interventionist expanded treatment opportunities. A variety of maneuvers are recommended to address the landing zone limitations to thoracic endografting imposed by the arch vessels: transostial bare stent placement, intentional occlusion of the arch vessel origin, vessel transposition, and bypass grafting. These adjunctive techniques can help us extend the option of a minimally invasive treatment to a greater number of patients with severe thoracic aortic lesions and comorbidities that place them at high risk for standard surgical intervention.

Outpatient Endovascular Intervention: Is it Safe?

Purpose:

To evaluate the feasibility and safety of outpatient percutaneous endovascular intervention in the treatment of arterial occlusive disease.

Methods:

The records of 134 patients who underwent 151 outpatient endovascular procedures between 1992 and 1997 were reviewed retrospectively. According to established protocol, focal lower limb (n = 145) and subclavian (n = 6) arterial lesions requiring relatively straightforward endoluminal interventions were appropriate for outpatient management provided the patients were free of significant comorbidities. A percutaneous transfemoral approach was used for lower limb lesions, while subclavian angioplasty was performed via a brachial access. Heparin anticoagulation was administered conservatively. Patients were discharged 3 hours after sheath removal.

Results:

The majority (98%) of patients were discharged as planned. Three (2%) patients were observed overnight in the hospital for treatment of acute iliac artery thrombosis, puncture-site bleeding, and suboptimal angioplasty. No patient required hospitalization following discharge. Periprocedural morbidity Was confined to 2 (1.5%) groin hematomas and 1 (0.7%) femoral pseudoaneurysm.

Conclusions:

Outpatient endovascular intervention appears safe; however, proper case selection and technical excellence are inseparable components for the success of this strategy.

Hazards of hospitalization: hospitalists and geriatricians educating medical students about delirium and falls in geriatric inpatients

Geriatric patients are at increased risk for complications from delirium or falls during hospitalization. Medical education, however, generally places little emphasis on the hazards of hospitalization for older inpatients. Geriatricians conducted a faculty development workshop for hospitalists about the hazards of hospitalization for geriatric patients, focusing on two common geriatric syndromes: delirium and falls. The hospitalists then ran workshops for third-year medical students during their inpatient medicine clerkship, introducing two simple tools for assessing fall risk and diagnosing delirium. Students used these tools to evaluate their own patients and then reviewed cases with a geriatrician at the end of one month. A total of 101 students participated in the project and completed a post-intervention multiple choice test, and 73 (72.2%) returned the records of 278 patient evaluations. Compared to the control group from the end of the previous year, test scores increased by an average of 0.84 out of 9 points (9.3% increase, p=0.005, t(117,.05/2)=2.87, p=0.0048). Students also identified 81 patients with delirium and 65 patients at high risk for falling. Hospitalists and geriatricians can effectively partner to increase students' knowledge of two major hazards of hospitalization for geriatric patients.

Endovascular Repair of the Thoracic Aorta: Lessons Learned

BACKGROUND

Available information on outcome and best strategies for thoracic endovascular repair is somewhat limited and unclear. We sought to gain a better understanding of these issues through a retrospective review of our 8-year clinical experience in the treatment of thoracic aortic aneurysms and dissections.

METHODS

A retrospective chart review of 186 patients undergoing stent-graft repair of thoracic aortic lesions at our institution during the 92-month period ending on December 31, 2004 was performed. Patients were divided into two groups based on the indication for treatment; group A had thoracic aortic aneurysms (TAA) and group B had type B aortic dissections (TBAD). Both groups were analyzed for outcome variables including technical success, mortality, major morbidity, endoleak rate and type, secondary endovascular interventions, and long-term survival. Mean follow-up was 40 months (range, 1 to 92 months).

RESULTS

Compared to group B, group A patients were older and had a higher incidence of peripheral vascular disease and chronic obstructive pulmonary disease. Sixty percent of all patients were American Society of Anesthesiologists class III and the remainder were class IV (38.3%) and V (1.7%). The procedure was completed in 180 patients (96.7%), with all 6 failures being access-related. The average procedure time was 149 minutes (range, 72 to 405). The 30-day mortality was 4.7% (9 patients), and serious morbidity was 19.9% (37 patients). Eight patients (4.3%) developed spinal cord ischemia, 4 immediately after the procedure and 4 delayed (1 to 3 days). Total hospital length of stay averaged 6.7 days. Secondary endovascular interventions were successful in 17 patients with angiographically confirmed endoleaks (type I and III). At an average follow-up of 40 months, freedom from all-cause mortality was 62.5% in group A and 58.1% in group B.

CONCLUSIONS

Stent-graft repair for TAA and TBAD can be achieved with high technical success and comparatively low rates of morbidity and mortality. Midterm survival appears to be favorable. Further refinements in device technology and procedural techniques are needed.

A user's guide to enhancing geriatrics in an undergraduate medical school curriculum: the ten-step model to winning the "geriatric game"

In 1999, the University of Rochester School of Medicine and Dentistry committed to major restructuring of its undergraduate medical school curriculum. A distinguishing feature of this reform was the planned emphasis on and integration of several core topics or themes throughout the 4 years of the curriculum. One of these curricular themes was aging. The faculty in geriatrics was presented with an unparalleled opportunity to develop a geriatrics curriculum of major proportions through the development of an aging theme. Through a user's guide approach based on the authors' experience to date, this article identifies the 10 steps necessary to "win the geriatric game" successfully integrating an aging theme into an undergraduate medical school curriculum. Since the initiation of the aging theme, several new courses, cases, and conferences have been added or enhanced, affecting all 4 years of the curriculum. Key operational challenges included successful engagement of course directors, tracking the actual experience of the aging theme, and evaluation of students' attainment of learning objectives and eventual career choices. The authors' experience suggests that an aging theme can successfully enhance the geriatrics curricular content of undergraduate education and strongly affect students across all 4 years. This 10-step approach may serve as a model for other universities committed to integrating geriatrics across the full undergraduate medical curriculum.

Hospital to home: Improving internal medicine residents' understanding of the needs of older persons after a hospital stay

Physicians-in-training discharge many older patients from the hospital, but few have any knowledge of what happens to the patients they send home, of how discharge plans are applied, or of the difficulties patients and their families face. The authors describe a pilot program, Hospital to Home, at the University of Rochester School of Medicine and Dentistry's internal medicine residency program, which uses home visits as an educational tool in geriatrics training. The program was begun in July 2001, and 23 residents have participated. Home visits expose residents in their first-year geriatrics rotation to the elements and outcomes of discharge planning and create a heightened awareness of the needs of older persons recently discharged from the hospital. The home visits are videotaped, and the residents present a videoconference based on the visits, which are attended by internal medicine residents, family medicine residents, and medical students. The authors describe the three-part Hospital to Home program, three vignettes that highlight learning experiences, and the residents' feedback about the experience and the use of audiovisual recording for education.

Stent graft repair in the aortic arch and descending thoracic aorta: a 4-year experience

BACKGROUND

Thoracic aortic aneurysms (TAAs) and type B aortic dissections (ADs) are relatively frequent, serious conditions that are often managed nonoperatively because of perceived poor outcome of standard surgical reconstruction. Recently developed stent graft techniques represent a more attractive, less invasive option. We sought to determine the technical feasibility and safety of endovascular repair in the thoracic aorta with a retrospective review of our experience with such an approach.

METHODS

Forty-seven patients received thoracic stent graft implants during the 4-year period ending March 31, 2002. All patients signed an Institutional Review Board-approved informed consent. Thirty-one patients had TAAs, and 16 had ADs. Device design and implant strategy were on the basis of evaluation of morphology with angiography and computed tomographic scan. The procedures were done with fluoroscopic guidance, with local anesthesia in five cases, spinal anesthesia in 19 cases, and general anesthesia in 23 cases. Endovascular access was achieved with femoral cutdown in 41 cases and a temporary iliac conduit in six cases. A Talent patient-specific device, with 4-mm to 6-mm oversize, was used in all. Proximal endograft attachment was in the descending thoracic aorta in 16 cases, parasubclavian in 21 cases, and the suprasubclavian aorta in 10 cases. Eight patients had adjunctive cervical reconstruction to transpose or revascularize the left subclavian or left common carotid arteries, enabling more proximal endograft attachment in the aortic arch.

RESULTS

Access failure occurred in one patient (2.1%). One patient (2.1%) died within 30 days of access-related iliac artery rupture. Another death occurred at 60 days from a ruptured thoracoabdominal aneurysm with type I endoleak. No instances of paraplegia, stroke, or surgical conversion were seen. Five patients (TAA) were found to have endoleak on 30-day computed tomographic scan. Repair of type I endoleak was undertaken in three cases at 1, 4, and 6 months. Eight patients (17%) had adverse events within the first 30 days. Length of follow-up ranged from 1 to 44 months, with a mean of 18 months. Two patients were lost to follow-up, and one withdrew from the study. Four additional mortalities were observed, none related to the endograft or aortic pathology.

CONCLUSION

Stent graft repair of TAA and AD is feasible and can be achieved with technical success and relatively low rates of perioperative morbidity and mortality. The Talent customized design proved versatile in various morphologies. More information is needed on indications, clinical efficacy, and long-term results.

Technical strategies to expand stent-graft applicability in the aortic arch and proximal descending thoracic aorta

The endovascular repair of thoracic aortic pathology is on an evolutionary threshold, as advancing technologies and techniques combine to offer the interventionist expanded treatment opportunities. A variety of maneuvers are recommended to address the landing zone limitations to thoracic endografting imposed by the arch vessels: transostial bare stent placement, intentional occlusion of the arch vessel origin, vessel transposition, and bypass grafting. These adjunctive techniques can help us extend the option of a minimally invasive treatment to a greater number of patients with severe thoracic aortic lesions and comorbidities that place them at high risk for standard surgical intervention.

Outpatient endovascular intervention: is it safe?

PURPOSE

To evaluate the feasibility and safety of outpatient percutaneous endovascular intervention in the treatment of arterial occlusive disease.

METHODS

The records of 134 patients who underwent 151 outpatient endovascular procedures between 1992 and 1997 were reviewed retrospectively. According to established protocol, focal lower limb (n = 145) and subclavian (n = 6) arterial lesions requiring relatively straightforward endoluminal interventions were appropriate for outpatient management provided the patients were free of significant comorbidities. A percutaneous transfemoral approach was used for lower limb lesions, while subclavian angioplasty was performed via a brachial access. Heparin anticoagulation was administered conservatively. Patients were discharged 3 hours after sheath removal.

RESULTS

The majority (98%) of patients were discharged as planned. Three (2%) patients were observed overnight in the hospital for treatment of acute iliac artery thrombosis, puncture-site bleeding, and suboptimal angioplasty. No patient required hospitalization following discharge. Periprocedural morbidity was confined to 2 (1.5%) groin hematomas and 1 (0.7%) femoral pseudoaneurysm.

CONCLUSIONS

Outpatient endovascular intervention appears safe; however, proper case selection and technical excellence are inseparable components for the success of this strategy.

Evolving indications for and early results of carotid artery stenting

BACKGROUND

While carotid endarterectomy continues to be the gold standard of treatment for most patients with significant carotid artery disease, there are cases where lesion or anatomy-related factors create situations less than ideal for conventional surgery. Other therapeutic modalities, such as endoluminal stenting, may represent reasonable options for such patients.

METHODS

Thirty-three patients with 70% or greater internal carotid artery lesions were treated by endovascular stent placement from July 1994 through June 1996. Indications included transient ischemic attacks in 20 and previous stroke in 4; and 9 were asymptomatic.

RESULT

Stents were placed successfully in all instances. Mortality and stroke rates were zero. All patients remained asymptomatic during follow-up (mean 8 months), and stent patency by duplex ultrasound has been 100%. A single instance of intrastent restenosis has been observed.

CONCLUSIONS

Endoluminal stenting is an investigational technique of unproven efficacy and long-term durability. Yet it appears technically feasible, and possibly reasonable, as an alternate option for cases unfavorable for standard surgery.

Folding and conformational studies on SCR1-3 domains of human complement receptor 1

Short consensus repeats SCR3 and SCR1-3 are soluble recombinant proteins, consisting of the third and first three N-terminal domains of complement receptor 1, respectively, which retain some anti-complement activity. The conformational stabilities and folding/unfolding of SCR3 and SCR1-3 have been studied using circular dichroism and equilibrium and pre-equilibrium fluorescence spectroscopy. Denaturation by guanidinium hydrochloride (GdnHCl) is rapid and completely reversible. Reduction of disulphide bridges in the folded proteins by beta-mercaptoethanol leads to an increase in fluorescence intensity. The fluorescence intensity of the folded proteins is approximately 7.5% of that of the respective unfolded proteins. The data can be approximated to a two-state transition between native and denatured forms of the proteins. SCR3 has a conformational stability in water of 12-13 kJ/mol whereas that of SCR1-3 is 19.5-19.9 kJ/mol depending upon the technique utilized. The heat capacity change associated with the unfolding of SCR1-3 was obtained by a series of GdnHCl unfolding experiments over a range of temperatures and was found to be 6.6 kJ/K.mol or 33.8 J/K.mol(residue). The refolding process of SCR3 was found to be simple, described by a single exponential equation, whereas that of SCR1-3 was found to be complex and could be fitted to a double exponential equation indicating the presence of folding intermediates.

Heel cord advancement in children with spastic equinus deformity

Heel cord advancement has been advocated for treatment of spastic equinus deformity. Transferring the gastrosoleus anteriorly weakens it by changing the lever arm rather than the resting length. A retrospective review of 90 children with 122 limbs undergoing heel cord advancement revealed 11% excellent, 53% good, and 35% poor results (average follow-up 9.7 years). The results were statistically better in diplegics and community walkers. The better results in previous studies may be due to procedure modifications and shorter follow-up. Since we obtain comparable results with simpler heel cord lengthenings, we no longer do heel cord advancement.