The cohort had an average age of 61.2 years (61% male, 53% Caucasian). The average follow-up time... more The cohort had an average age of 61.2 years (61% male, 53% Caucasian). The average follow-up time was 3.9 years. A stratified analysis demonstrated the most sensitive cutoff for mortality was aortic diameter >44 mm (P < .0002), and it appeared to be a threshold effect with minimal additional information added by finer size stratification. FL diameter did not predict mortality in our series (P ¼ .4). Intervention-free survival, alternatively, appeared to decrease over the range of diameters from 35 to 44 mm (P < .008). A false lumen diameter >22 mm was associated with decreased intervention-free survival (P < .04). Diameter >44 mm persisted as a risk factor (HR, 8.7; P < .0001) after adjustment for diabetes (6.5; P < .0002), age (1.05/yr; P < .0005), history of stroke (5.6; P < .005), connective tissue disorder (2.3; P < .008) and syncope on admission (9.6; P < .05). The 1-, 5-, and 10-year intervention rate for patients with an admission aortic diameter >44 mm was 12.5%, 18.5%, and 27.7% compared with 4.6%, 13.7%, and 12.2% in the #44 mm group (P < .001). Conclusions: Aortic diameter >44 mm is a predictor of mortality after adjustment for other significant risk factors. A FL diameter >22 mm was associated with decreased intervention-free survival. uATBAD patients with these high-risk criteria should be considered for TEVAR.
Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer... more Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer than carotid endarterectomy (CEA) for patients with a contralateral internal carotid occlusion (CCO). Arguably, with a CCO, CAS should be even safer than CEA if a shunt is not used. Accordingly, we reviewed our experience with 2183 CEAs performed routinely without a shunt to evaluate the risk of CEA performed in a subset of 147 patients with a CCO. Methods: Between 1988 and 2011, 147 CEAs (111 men [75%], 36 women [25%]) were routinely performed without a shunt despite CCO. Of these patients, 76% were asymptomatic. CEAs were performed by seven surgeons using standard techniques (not eversion), with patients under general anesthesia and blood pressure maintained at >130 mm Hg. All patients received heparin (7500 U), and protamine reversal was routine. Median cross-clamp time was 20 minutes (range, 14-40 minutes). Results: Three neurologic events occurred #30 days (2.0%). One transient ischemic attack (TIA) occurred immediately, and one occurred on the first postoperative day due to occlusion of the endarterectomy site. One patient sustained an immediate stroke and died of a large computed tomography-documented atheroembolic shower. Conclusions: Our data demonstrate the safety of CEA in the presence of a CCO, even when performed without a shunt. It is unlikely that the stroke or delayed TIA could be attributed to nonshunting or CCO. Even if so, the stroke and death rates would be lower than those previously reported for patients undergoing CEA in the presence of a CCO. This may be due to short cross-clamp times, careful technique, general anesthesia, and blood pressure support. Given these low adverse event rates, our experience refutes the assumption that patients with a CCO are at such a high risk for CEA that the only alternative is CAS.
Objective: Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. ... more Objective: Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. In the past, reported patency rates (37%-76%) for these extra-anatomic grafts have been inferior to those for anatomic aortic grafting. Reported low survival rates after AxFB (40%-50%) have confirmed that these procedures have been used primarily in patients at high risk for complications from aortofemoral bypass. However, modern medical and anesthesia management, preoperative scanning, donor artery preparation, postoperative graft surveillance, and graft technology may improve outcomes after AxFB, possibly supporting expansion of its use. We therefore report our last 15-year experience with AxFB. Methods: Ring-reinforced, 8-mm expanded polytetrafluoroethylene grafts were used in all cases. The cross-femoral limb of axillobifemoral bypass (AxBFB) grafts was preconstructed. Heparin was administered intraoperatively, with protamine reversal. Loss of primary patency was defined as graft thrombosis of part or all of the inserted graft. Five-year primary patency rates were calculated by Kaplan-Meier analysis. Results: Between February 1991 and June 2016, a total of 161 grafts were inserted (85 AxBFBs and 76 axillounifemoral bypasses [AxUFBs]) in 91 male and 70 female patients (median age, 72.6 years; mean age, 73 years; range, 41-94 years). Indications for treatment were rest pain (49.6%), ischemic lesions (26%), claudication (22.3%), failed prior revascularization (9.3%), infection (3.7%), and dissecting aneurysm (1.2%). Reasons for performing AxFB rather than aortofemoral bypass were hostile aorta (44.1%), high risk (19.2%), prior failed reconstruction (12.4%), advanced age (8.7%), infection (4.3%), hostile abdomen (4.3%), aortic dissection (0.6%), and morbid obesity (0.6%). During follow up, 63 patients died, 17 within the first year; but only 3 patients died within 30 days of surgery (performed to treat an acute aortic occlusion). The 5-year survival rate was 55%. Five-year patency rates were 83.7% for all procedures, 81.8% for AxBFB, and 85.5% for AxUFB; the difference between AxBFB and AxUFB was not significant. Conclusions: Our data indicate that AxBFB and AxUFB performed with the use of modern protocols and technology may render them an acceptable valid primary intervention in patients in whom endovascular treatment has failed or is unlikely to offer long-term success. The simplicity of performing these grafts and their low mortality and morbidity lend their application to surgeons with limited open aortic experience. Because AxUFB and AxBFB have similar patency rates, AxBFB should be reserved for bilateral indications.
Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abd... more Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abdominal aortic surgery. Surgeons restore continuity of the vein due to concern that ligation could cause renal compromise or hematuria. However, we report the short and long-term safety of left renal vein division and ligation. Method: Between 1992 and 2007, we divided the left renal vein in 56 patients (40 males, 16 females) ages 57 to 84 (average 74-years-old) who were treated for aortic occlusive disease (9) or abdominal aortic aneurysm (47). Patients requiring concomitant renal artery reconstruction were excluded from this review. Suprarenal cross-clamp was used in 51 patients with temporary vessel-loop control of the renal arteries. Creatinine (Cr) and glomerular filtration rates (eGFR) were measured pre-, post-, and long-term after surgery. Outpatient records of all patients that had survived more than 12 months were also reviewed in order to evaluate the late effects on renal function or symptoms possibly related to LRVDAL. Results: Median procedure duration was 157 (61-375) minutes. Median cross-clamp time was 16 (10-45) minutes. Median intensive care unit (ICU) and hospital length of stays were 2 (1-11) days and 7 (4-58) days, respectively. There were no deaths. There were no complications directly related to renal vein ligation. Hematuria, seen in 2 patients, was a result of traumatic insertion of a Foley catheter. Median pre-op and discharge Cr levels were 1.1 mg/dL (0.7-2.4 mg/dL) and 1.1 mg/dL (0.6-2.1 mg/dL), respectively (P < .5). Median change in Cr was 0.0 mg/dL and only increased in 14 patients (maximum increase 0.9 mg/dL). Median pre-op and discharge eGFR was 61 mL/minute (28-137 mL/minute/ 1.73 m2) and 67 mL/minute (32-138 mL/minute/1.73 m2), respectively (P < .5). Cr and eGFR in the 2 patients with a Cr of >2.0 mg/dL remained unchanged post-op. Only 2 patients with a Cr of <2.0 mg/dL had a post-op Cr >2.0 mg/dL and both returned to normal by day 3 post-op. Thirty-six patients have been followed for more than a year (median 34.5 months, maximum 144 months) and Cr has remained stable in all but 2 patients. These 2 patients, both with a pre-op Cr of 1.5 mg/dL, subsequently developed Cr levels of 2.1 mg/dL and 2.4 mg/dL but maintained baseline Cr levels for 25 and 34 months, respectively, before demonstrating these elevated levels which have proven to be unrelated to renal vein ligation. Hematuria and flank pain have never been recorded after discharge. Conclusion: Restoration of left renal vein continuity after LRVDAL may be unnecessary since renal compromise and hematuria was not encountered in this long-term analysis.
Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of... more Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral (SFA) and popliteal arteries. CryoPlasty therapy (PolarCath, Boston Scientific Corp, Natick, Mass) is a novel approach designed to significantly reduce injury, elastic recoil, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty (PTA) with cold thermal energy applied to the plaque and vessel wall. We previously reported a technical success rate of 96% and a 12-month freedom from restenosis rate of 82.2%. However, a review of the original cohort supplemented by experience with a further 47 lesions has demonstrated less desirable results. Methods: From December 2003 through July 2007, 92 lesions in 64 consecutive patients were treated and followed up for a median of 16 months with statistically significant follow-up at 24 months. Results: The immediate technical success rate was 88%. Nine stents were immediately required after unsuccessful CryoPlasty (9.8%) five of which were as a result of a dissection. No unanticipated adverse events occurred, specifically, no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. Vascular calcification was responsible for technical failure in six of the 11 immediately unsuccessful procedures. Freedom from restenosis for successfully treated lesions was 57% and 49% at 12 and 24 months, respectively. CryoPlasty of heavily calcified lesions, vein graft lesions, and in-stent stenosis faired poorly. Excluding these lesions from analysis would have resulted in an immediate success of 94% (81 of 86) and freedom from restenosis of 61% and 52% at 12 and 24 months, respectively. However, on an intention-to-treat basis, freedom from restenosis was 47% and 38% at 12 and 24 months, and CryoPlasty added approximately $1700 to the cost of each procedure. Conclusion: Analysis of this expanded, longer-term data suggests that our earlier, smaller study provided an overly optimistic appraisal of the benefits of CryoPlasty. It is possible that a larger analysis might have identified a subset of patients or lesions that would benefit from CryoPlasty, but considering the additional cost, we no longer use this technique in our practice.
Objective: Expanded polytetrafluoroethylene (ePTFE) grafts have become an acceptable prosthetic a... more Objective: Expanded polytetrafluoroethylene (ePTFE) grafts have become an acceptable prosthetic alternative to autologous vein for infrainguinal arterial reconstructions. Recently, heparin bonding to the graft's luminal surface has been used as an adjunctive method of improving graft patency. We retrospectively evaluated a prospective experience with heparin-bonded ePTFE (HePTFE) vs the results of a prior experience with standard ePTFE (SePTFE) to compare patency rates in above-knee (AK) and below-knee (BK) femoropopliteal bypass through the 5-year follow-up. Methods: Prosthetic femoropopliteal bypasses performed by our four-surgeon group were constructed using 6-mm SePTFE grafts before August 2007. Subsequently, all such bypasses were constructed using 6-mm HePTFE (Propaten graft; W. L. Gore & Associates, Flagstaff, Ariz). The surgical technique used in all cases throughout the study was similar irrespective of surgeon or graft material. Loss of primary patency was defined by graft thrombosis; duplex scan confirmed graft failure. Descriptive estimation of patency rates was carried out using standard KaplaneMeier methods. Cox proportional hazards regression was used to analyze relationships between predictors and time to loss of patency. Results: There were 192 AK (87 Propaten, 105 SePTFE) and 60 BK (42 Propaten, 18 SePTFE) grafts. Overall primary patency for Propaten was statistically better than SePTFE at years 1 (93.6% vs 84.2%), 2 (79.7% vs 73.8%), 3 (79.7% vs 69.5%), 4 (74.5% vs 59.9%) and 5 (74.5% vs 56.2%; log-rank test, P [ .036). Five-year primary patency was superior for Propaten AK grafts (85.2% vs 59.3%; log-rank test, P [ .028) and for Propaten BK grafts (59.6% vs 0.0/undeterminable; log-rank test, P [ .016). Variables significantly associated with loss of patency for Propaten and SePTFE were claudication (hazard ratio [HR], 0.41), age (HR, 0.95), isolated popliteal artery (HR, 3.1-4.4), and ankle-brachial index after the procedure (HR, 0.10). Controlling for conduit effect, clopidogrel use did not significantly affect patency (P [ .076). No grafts were associated with heparin-induced thrombocytopenia. Conclusions: These data show that the Propaten HePTFE graft offered significantly better long-term patency over the SePTFE graft, suggesting Propaten as the prosthetic graft of choice for bypasses to the femoropopliteal artery when autologous vein is unavailable or inappropriate.
Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of... more Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral (SFA) and popliteal arteries. CryoPlasty therapy (PolarCath, Boston Scientific Corp, Natick, Mass) is a novel approach designed to significantly reduce injury, elastic recoil, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty (PTA) with cold thermal energy applied to the plaque and vessel wall. We previously reported a technical success rate of 96% and a 12-month freedom from restenosis rate of 82.2%. However, a review of the original cohort supplemented by experience with a further 47 lesions has demonstrated less desirable results. Methods: From December 2003 through July 2007, 92 lesions in 64 consecutive patients were treated and followed up for a median of 16 months with statistically significant follow-up at 24 months. Results: The immediate technical success rate was 88%. Nine stents were immediately required after unsuccessful CryoPlasty (9.8%) five of which were as a result of a dissection. No unanticipated adverse events occurred, specifically, no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. Vascular calcification was responsible for technical failure in six of the 11 immediately unsuccessful procedures. Freedom from restenosis for successfully treated lesions was 57% and 49% at 12 and 24 months, respectively. CryoPlasty of heavily calcified lesions, vein graft lesions, and in-stent stenosis faired poorly. Excluding these lesions from analysis would have resulted in an immediate success of 94% (81 of 86) and freedom from restenosis of 61% and 52% at 12 and 24 months, respectively. However, on an intention-to-treat basis, freedom from restenosis was 47% and 38% at 12 and 24 months, and CryoPlasty added approximately $1700 to the cost of each procedure. Conclusion: Analysis of this expanded, longer-term data suggests that our earlier, smaller study provided an overly optimistic appraisal of the benefits of CryoPlasty. It is possible that a larger analysis might have identified a subset of patients or lesions that would benefit from CryoPlasty, but considering the additional cost, we no longer use this technique in our practice.
Journal of Vascular Surgery Cases, Innovations and Techniques, 2019
Endovascular repair has become the standard of care for treatment of abdominal aortic aneurysms. ... more Endovascular repair has become the standard of care for treatment of abdominal aortic aneurysms. The endografts and delivery systems for endovascular aneurysm repair have undergone multiple generations of technologic advancements. However, a significant remaining challenge for a satisfactory long-term outcome is to improve the performance of these devices in nonideal proximal sealing zones. In particular, short (<15 mm) and highly angulated (>60 degrees) necks can threaten long-term exclusion of the aneurysm even with the current generation of endografts. One of the main reasons for proximal infrarenal neck failure is the inability to accurately position the endograft precisely below both renal arteries. This is a report of the first-inhuman implantations of the GORE EXCLUDER Conformable AAA Endoprosthesis (W. L. Gore & Associates, Flagstaff, Ariz), an investigational device, in anatomies with standard neck lengths and angulation. This device has been designed to provide repositionability, conformability, and, for the first time, optional angulation control.
Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. In the past... more Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. In the past, reported patency rates (37%-76%) for these extra-anatomic grafts have been inferior to those for anatomic aortic grafting. Reported low survival rates after AxFB (40%-50%) have confirmed that these procedures have been used primarily in patients at high risk for complications from aortofemoral bypass. However, modern medical and anesthesia management, preoperative scanning, donor artery preparation, postoperative graft surveillance, and graft technology may improve outcomes after AxFB, possibly supporting expansion of its use. We therefore report our last 15-year experience with AxFB. Ring-reinforced, 8-mm expanded polytetrafluoroethylene grafts were used in all cases. The cross-femoral limb of axillobifemoral bypass (AxBFB) grafts was preconstructed. Heparin was administered intraoperatively, with protamine reversal. Loss of primary patency was defined as graft thrombosis of part or a...
The recent and continuing developments in radiotherapy, gene therapy, and the technologies of ima... more The recent and continuing developments in radiotherapy, gene therapy, and the technologies of imaging, materials, and devices, as well as the techniques for their implementation, have expanded the options available for the treatment of peripheral vascular disease. Though long-term data are still lacking, percutaneous transluminal angioplasty (PTA) has developed into a treatment modality in its own right and continues to be an adjuvant treatment to traditional surgical revascularization. Numerous stents and grafts are currently available for the treatment of arterial lesions and aneurysms, while the testing of many more continues. In addition to these new devices, developments in gene therapy and brachytherapy have brought several new minimally invasive options to the treatment of peripheral vascular disease.
Purpose: Proponents of carotid angioplasty and stenting suggest that "high risk" patients, define... more Purpose: Proponents of carotid angioplasty and stenting suggest that "high risk" patients, defined as patients excluded from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and Asymptomatic Carotid Atherosclerosis Study (ACAS), may have a significantly higher risk of stroke with carotid endarterectomy (CEA). However, this selected patient cohort has been poorly studied. Methods: A retrospective review of patients who underwent CEA during a 2-year period at a tertiary referral institution was performed. Each patient was evaluated and categorized, according to the exclusion criteria, by NASCET and ACAS standards. Statistical analysis using χ 2 and Fisher exact tests was performed. Results: There were 366 CEAs performed on 348 patients, including 32 (8.7%) for recurrent stenosis. A subgroup of 169 (46.2%) patients were trial ineligible. Focal ipsilateral symptoms were present in 148 (40.4%) of the patients. There were 9 (2.5%) strokes and 1 (0.3%) death, secondary to a major stroke, for an overall stroke and death rate of 2.5%. Trial-eligible patients had a stroke/death rate of 1.5% (3/197) while trial-ineligible patients had a 3.6% (6/169) stroke/death rate (P = .17). Conclusion: Patients who were considered high risk for CEA as defined by trial ineligibility were common, comprising approximately half of our patients. Although trial-ineligible patients had a nonsignificant trend toward higher neurologic morbidity when compared with the eligible group, the risks were still comparable with NASCET/ACAS results. CEA was a safe procedure even in this "high risk" group. As such, ineligibility for a randomized carotid intervention trial should not be employed as a "de novo" indication for carotid stenting.
Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of... more Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral (SFA) and popliteal arteries. CryoPlasty therapy (PolarCath, Boston Scientific Corp, Natick, Mass) is a novel approach designed to significantly reduce injury, elastic recoil, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty (PTA) with cold thermal energy applied to the plaque and vessel wall. We previously reported a technical success rate of 96% and a 12-month freedom from restenosis rate of 82.2%. However, a review of the original cohort supplemented by experience with a further 47 lesions has demonstrated less desirable results. Methods: From December 2003 through July 2007, 92 lesions in 64 consecutive patients were treated and followed up for a median of 16 months with statistically significant follow-up at 24 months. Results: The immediate technical success rate was 88%. Nine stents were immediately required after unsuccessful CryoPlasty (9.8%) five of which were as a result of a dissection. No unanticipated adverse events occurred, specifically, no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. Vascular calcification was responsible for technical failure in six of the 11 immediately unsuccessful procedures. Freedom from restenosis for successfully treated lesions was 57% and 49% at 12 and 24 months, respectively. CryoPlasty of heavily calcified lesions, vein graft lesions, and in-stent stenosis faired poorly. Excluding these lesions from analysis would have resulted in an immediate success of 94% (81 of 86) and freedom from restenosis of 61% and 52% at 12 and 24 months, respectively. However, on an intention-to-treat basis, freedom from restenosis was 47% and 38% at 12 and 24 months, and CryoPlasty added approximately $1700 to the cost of each procedure. Conclusion: Analysis of this expanded, longer-term data suggests that our earlier, smaller study provided an overly optimistic appraisal of the benefits of CryoPlasty. It is possible that a larger analysis might have identified a subset of patients or lesions that would benefit from CryoPlasty, but considering the additional cost, we no longer use this technique in our practice.
Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abd... more Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abdominal aortic surgery. Surgeons restore continuity of the vein due to concern that ligation could cause renal compromise or hematuria. However, we report the short and long-term safety of left renal vein division and ligation. Method: Between 1992 and 2007, we divided the left renal vein in 56 patients (40 males, 16 females) ages 57 to 84 (average 74-years-old) who were treated for aortic occlusive disease (9) or abdominal aortic aneurysm (47). Patients requiring concomitant renal artery reconstruction were excluded from this review. Suprarenal cross-clamp was used in 51 patients with temporary vessel-loop control of the renal arteries. Creatinine (Cr) and glomerular filtration rates (eGFR) were measured pre-, post-, and long-term after surgery. Outpatient records of all patients that had survived more than 12 months were also reviewed in order to evaluate the late effects on renal function or symptoms possibly related to LRVDAL. Results: Median procedure duration was 157 (61-375) minutes. Median cross-clamp time was 16 (10-45) minutes. Median intensive care unit (ICU) and hospital length of stays were 2 (1-11) days and 7 (4-58) days, respectively. There were no deaths. There were no complications directly related to renal vein ligation. Hematuria, seen in 2 patients, was a result of traumatic insertion of a Foley catheter. Median pre-op and discharge Cr levels were 1.1 mg/dL (0.7-2.4 mg/dL) and 1.1 mg/dL (0.6-2.1 mg/dL), respectively (P < .5). Median change in Cr was 0.0 mg/dL and only increased in 14 patients (maximum increase 0.9 mg/dL). Median pre-op and discharge eGFR was 61 mL/minute (28-137 mL/minute/ 1.73 m2) and 67 mL/minute (32-138 mL/minute/1.73 m2), respectively (P < .5). Cr and eGFR in the 2 patients with a Cr of >2.0 mg/dL remained unchanged post-op. Only 2 patients with a Cr of <2.0 mg/dL had a post-op Cr >2.0 mg/dL and both returned to normal by day 3 post-op. Thirty-six patients have been followed for more than a year (median 34.5 months, maximum 144 months) and Cr has remained stable in all but 2 patients. These 2 patients, both with a pre-op Cr of 1.5 mg/dL, subsequently developed Cr levels of 2.1 mg/dL and 2.4 mg/dL but maintained baseline Cr levels for 25 and 34 months, respectively, before demonstrating these elevated levels which have proven to be unrelated to renal vein ligation. Hematuria and flank pain have never been recorded after discharge. Conclusion: Restoration of left renal vein continuity after LRVDAL may be unnecessary since renal compromise and hematuria was not encountered in this long-term analysis.
Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked d... more Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked data concerning clamp-to-shunt time. There were no significant differences between the three groups in the following characteristics: sex, age, co-morbidity, patch/no-patch and symptomatic/ asymptomatic patients (t-tests). 30-day stroke/death rate increased with longer clamp-to-shunt time: 3,6%, 5,6% and 12,8% in group 1 (nϭ28), 2 (nϭ89), and 3 (nϭ39), respectively. We analyzed this effect using a binary logistic regression model and found a two-tailed p-value of 0,093. The confounding effect of peri-operative microembolic signals and intracranial flow decrease measured by TCD at 1 and 3 minutes after carotid cross clamping was controlled for. Conclusions: Longer carotid-clamp-to-shunt time tends to increase 30 day stroke/death rate post-CEA in our selective shunting protocol. When clamp-to-shunt time exceeded 7 minutes, more than 1 out of 8 patients ended with stroke or death. Again, time is brain!
Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked d... more Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked data concerning clamp-to-shunt time. There were no significant differences between the three groups in the following characteristics: sex, age, co-morbidity, patch/no-patch and symptomatic/ asymptomatic patients (t-tests). 30-day stroke/death rate increased with longer clamp-to-shunt time: 3,6%, 5,6% and 12,8% in group 1 (nϭ28), 2 (nϭ89), and 3 (nϭ39), respectively. We analyzed this effect using a binary logistic regression model and found a two-tailed p-value of 0,093. The confounding effect of peri-operative microembolic signals and intracranial flow decrease measured by TCD at 1 and 3 minutes after carotid cross clamping was controlled for. Conclusions: Longer carotid-clamp-to-shunt time tends to increase 30 day stroke/death rate post-CEA in our selective shunting protocol. When clamp-to-shunt time exceeded 7 minutes, more than 1 out of 8 patients ended with stroke or death. Again, time is brain!
Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer... more Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer than carotid endarterectomy (CEA) for patients with a contralateral internal carotid occlusion (CCO). Arguably, with a CCO, CAS should be even safer than CEA if a shunt is not used. Accordingly, we reviewed our experience with 2183 CEAs performed routinely without a shunt to evaluate the risk of CEA performed in a subset of 147 patients with a CCO. Methods: Between 1988 and 2011, 147 CEAs (111 men [75%], 36 women [25%]) were routinely performed without a shunt despite CCO. Of these patients, 76% were asymptomatic. CEAs were performed by seven surgeons using standard techniques (not eversion), with patients under general anesthesia and blood pressure maintained at >130 mm Hg. All patients received heparin (7500 U), and protamine reversal was routine. Median cross-clamp time was 20 minutes (range, 14-40 minutes). Results: Three neurologic events occurred #30 days (2.0%). One transient ischemic attack (TIA) occurred immediately, and one occurred on the first postoperative day due to occlusion of the endarterectomy site. One patient sustained an immediate stroke and died of a large computed tomography-documented atheroembolic shower. Conclusions: Our data demonstrate the safety of CEA in the presence of a CCO, even when performed without a shunt. It is unlikely that the stroke or delayed TIA could be attributed to nonshunting or CCO. Even if so, the stroke and death rates would be lower than those previously reported for patients undergoing CEA in the presence of a CCO. This may be due to short cross-clamp times, careful technique, general anesthesia, and blood pressure support. Given these low adverse event rates, our experience refutes the assumption that patients with a CCO are at such a high risk for CEA that the only alternative is CAS.
This experiment evaluated enterally administered low molecular weight heparin (LMWH) combined wit... more This experiment evaluated enterally administered low molecular weight heparin (LMWH) combined with sodium N-[10-(2hydroxybenzoyl)amino] decanoate (SNAD) for the treatment of induced venous thrombosis. Summary Background Data SNAD is a delivery agent that potentiates the gastrointestinal absorption of LMWH.
Objective: Several prosthetic materials have been used for femoropopliteal bypass grafting in pat... more Objective: Several prosthetic materials have been used for femoropopliteal bypass grafting in patients with peripheral vascular disease in whom a venous bypass is not possible. Expanded polytetrafluoroethylene (ePTFE) is the most commonly used, but patency results have not always equaled those achieved with vein, especially in below-knee reconstructions. This study assessed the performance of a new heparin-bonded ePTFE vascular graft that was designed to provide resistance to thrombosis and thereby decrease early graft failures and possibly prolong patency. Method: From June 2002 to June 2003, 86 patients (62 men and 24 women; mean age, 70 years; 99 diseased limbs) were enrolled prospectively in a nonrandomized, multicenter study of the heparin-bonded ePTFE graft. Fifty-five above-knee and 44 below-knee (including 21 femorocrural) procedures were performed. Follow-up evaluations consisted of clinical examinations, ultrasonographic studies, and distal pulse assessments. Patency and limb salvage rates were assessed by using life-table analyses.
The cohort had an average age of 61.2 years (61% male, 53% Caucasian). The average follow-up time... more The cohort had an average age of 61.2 years (61% male, 53% Caucasian). The average follow-up time was 3.9 years. A stratified analysis demonstrated the most sensitive cutoff for mortality was aortic diameter >44 mm (P < .0002), and it appeared to be a threshold effect with minimal additional information added by finer size stratification. FL diameter did not predict mortality in our series (P ¼ .4). Intervention-free survival, alternatively, appeared to decrease over the range of diameters from 35 to 44 mm (P < .008). A false lumen diameter >22 mm was associated with decreased intervention-free survival (P < .04). Diameter >44 mm persisted as a risk factor (HR, 8.7; P < .0001) after adjustment for diabetes (6.5; P < .0002), age (1.05/yr; P < .0005), history of stroke (5.6; P < .005), connective tissue disorder (2.3; P < .008) and syncope on admission (9.6; P < .05). The 1-, 5-, and 10-year intervention rate for patients with an admission aortic diameter >44 mm was 12.5%, 18.5%, and 27.7% compared with 4.6%, 13.7%, and 12.2% in the #44 mm group (P < .001). Conclusions: Aortic diameter >44 mm is a predictor of mortality after adjustment for other significant risk factors. A FL diameter >22 mm was associated with decreased intervention-free survival. uATBAD patients with these high-risk criteria should be considered for TEVAR.
Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer... more Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer than carotid endarterectomy (CEA) for patients with a contralateral internal carotid occlusion (CCO). Arguably, with a CCO, CAS should be even safer than CEA if a shunt is not used. Accordingly, we reviewed our experience with 2183 CEAs performed routinely without a shunt to evaluate the risk of CEA performed in a subset of 147 patients with a CCO. Methods: Between 1988 and 2011, 147 CEAs (111 men [75%], 36 women [25%]) were routinely performed without a shunt despite CCO. Of these patients, 76% were asymptomatic. CEAs were performed by seven surgeons using standard techniques (not eversion), with patients under general anesthesia and blood pressure maintained at >130 mm Hg. All patients received heparin (7500 U), and protamine reversal was routine. Median cross-clamp time was 20 minutes (range, 14-40 minutes). Results: Three neurologic events occurred #30 days (2.0%). One transient ischemic attack (TIA) occurred immediately, and one occurred on the first postoperative day due to occlusion of the endarterectomy site. One patient sustained an immediate stroke and died of a large computed tomography-documented atheroembolic shower. Conclusions: Our data demonstrate the safety of CEA in the presence of a CCO, even when performed without a shunt. It is unlikely that the stroke or delayed TIA could be attributed to nonshunting or CCO. Even if so, the stroke and death rates would be lower than those previously reported for patients undergoing CEA in the presence of a CCO. This may be due to short cross-clamp times, careful technique, general anesthesia, and blood pressure support. Given these low adverse event rates, our experience refutes the assumption that patients with a CCO are at such a high risk for CEA that the only alternative is CAS.
Objective: Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. ... more Objective: Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. In the past, reported patency rates (37%-76%) for these extra-anatomic grafts have been inferior to those for anatomic aortic grafting. Reported low survival rates after AxFB (40%-50%) have confirmed that these procedures have been used primarily in patients at high risk for complications from aortofemoral bypass. However, modern medical and anesthesia management, preoperative scanning, donor artery preparation, postoperative graft surveillance, and graft technology may improve outcomes after AxFB, possibly supporting expansion of its use. We therefore report our last 15-year experience with AxFB. Methods: Ring-reinforced, 8-mm expanded polytetrafluoroethylene grafts were used in all cases. The cross-femoral limb of axillobifemoral bypass (AxBFB) grafts was preconstructed. Heparin was administered intraoperatively, with protamine reversal. Loss of primary patency was defined as graft thrombosis of part or all of the inserted graft. Five-year primary patency rates were calculated by Kaplan-Meier analysis. Results: Between February 1991 and June 2016, a total of 161 grafts were inserted (85 AxBFBs and 76 axillounifemoral bypasses [AxUFBs]) in 91 male and 70 female patients (median age, 72.6 years; mean age, 73 years; range, 41-94 years). Indications for treatment were rest pain (49.6%), ischemic lesions (26%), claudication (22.3%), failed prior revascularization (9.3%), infection (3.7%), and dissecting aneurysm (1.2%). Reasons for performing AxFB rather than aortofemoral bypass were hostile aorta (44.1%), high risk (19.2%), prior failed reconstruction (12.4%), advanced age (8.7%), infection (4.3%), hostile abdomen (4.3%), aortic dissection (0.6%), and morbid obesity (0.6%). During follow up, 63 patients died, 17 within the first year; but only 3 patients died within 30 days of surgery (performed to treat an acute aortic occlusion). The 5-year survival rate was 55%. Five-year patency rates were 83.7% for all procedures, 81.8% for AxBFB, and 85.5% for AxUFB; the difference between AxBFB and AxUFB was not significant. Conclusions: Our data indicate that AxBFB and AxUFB performed with the use of modern protocols and technology may render them an acceptable valid primary intervention in patients in whom endovascular treatment has failed or is unlikely to offer long-term success. The simplicity of performing these grafts and their low mortality and morbidity lend their application to surgeons with limited open aortic experience. Because AxUFB and AxBFB have similar patency rates, AxBFB should be reserved for bilateral indications.
Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abd... more Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abdominal aortic surgery. Surgeons restore continuity of the vein due to concern that ligation could cause renal compromise or hematuria. However, we report the short and long-term safety of left renal vein division and ligation. Method: Between 1992 and 2007, we divided the left renal vein in 56 patients (40 males, 16 females) ages 57 to 84 (average 74-years-old) who were treated for aortic occlusive disease (9) or abdominal aortic aneurysm (47). Patients requiring concomitant renal artery reconstruction were excluded from this review. Suprarenal cross-clamp was used in 51 patients with temporary vessel-loop control of the renal arteries. Creatinine (Cr) and glomerular filtration rates (eGFR) were measured pre-, post-, and long-term after surgery. Outpatient records of all patients that had survived more than 12 months were also reviewed in order to evaluate the late effects on renal function or symptoms possibly related to LRVDAL. Results: Median procedure duration was 157 (61-375) minutes. Median cross-clamp time was 16 (10-45) minutes. Median intensive care unit (ICU) and hospital length of stays were 2 (1-11) days and 7 (4-58) days, respectively. There were no deaths. There were no complications directly related to renal vein ligation. Hematuria, seen in 2 patients, was a result of traumatic insertion of a Foley catheter. Median pre-op and discharge Cr levels were 1.1 mg/dL (0.7-2.4 mg/dL) and 1.1 mg/dL (0.6-2.1 mg/dL), respectively (P < .5). Median change in Cr was 0.0 mg/dL and only increased in 14 patients (maximum increase 0.9 mg/dL). Median pre-op and discharge eGFR was 61 mL/minute (28-137 mL/minute/ 1.73 m2) and 67 mL/minute (32-138 mL/minute/1.73 m2), respectively (P < .5). Cr and eGFR in the 2 patients with a Cr of >2.0 mg/dL remained unchanged post-op. Only 2 patients with a Cr of <2.0 mg/dL had a post-op Cr >2.0 mg/dL and both returned to normal by day 3 post-op. Thirty-six patients have been followed for more than a year (median 34.5 months, maximum 144 months) and Cr has remained stable in all but 2 patients. These 2 patients, both with a pre-op Cr of 1.5 mg/dL, subsequently developed Cr levels of 2.1 mg/dL and 2.4 mg/dL but maintained baseline Cr levels for 25 and 34 months, respectively, before demonstrating these elevated levels which have proven to be unrelated to renal vein ligation. Hematuria and flank pain have never been recorded after discharge. Conclusion: Restoration of left renal vein continuity after LRVDAL may be unnecessary since renal compromise and hematuria was not encountered in this long-term analysis.
Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of... more Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral (SFA) and popliteal arteries. CryoPlasty therapy (PolarCath, Boston Scientific Corp, Natick, Mass) is a novel approach designed to significantly reduce injury, elastic recoil, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty (PTA) with cold thermal energy applied to the plaque and vessel wall. We previously reported a technical success rate of 96% and a 12-month freedom from restenosis rate of 82.2%. However, a review of the original cohort supplemented by experience with a further 47 lesions has demonstrated less desirable results. Methods: From December 2003 through July 2007, 92 lesions in 64 consecutive patients were treated and followed up for a median of 16 months with statistically significant follow-up at 24 months. Results: The immediate technical success rate was 88%. Nine stents were immediately required after unsuccessful CryoPlasty (9.8%) five of which were as a result of a dissection. No unanticipated adverse events occurred, specifically, no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. Vascular calcification was responsible for technical failure in six of the 11 immediately unsuccessful procedures. Freedom from restenosis for successfully treated lesions was 57% and 49% at 12 and 24 months, respectively. CryoPlasty of heavily calcified lesions, vein graft lesions, and in-stent stenosis faired poorly. Excluding these lesions from analysis would have resulted in an immediate success of 94% (81 of 86) and freedom from restenosis of 61% and 52% at 12 and 24 months, respectively. However, on an intention-to-treat basis, freedom from restenosis was 47% and 38% at 12 and 24 months, and CryoPlasty added approximately $1700 to the cost of each procedure. Conclusion: Analysis of this expanded, longer-term data suggests that our earlier, smaller study provided an overly optimistic appraisal of the benefits of CryoPlasty. It is possible that a larger analysis might have identified a subset of patients or lesions that would benefit from CryoPlasty, but considering the additional cost, we no longer use this technique in our practice.
Objective: Expanded polytetrafluoroethylene (ePTFE) grafts have become an acceptable prosthetic a... more Objective: Expanded polytetrafluoroethylene (ePTFE) grafts have become an acceptable prosthetic alternative to autologous vein for infrainguinal arterial reconstructions. Recently, heparin bonding to the graft's luminal surface has been used as an adjunctive method of improving graft patency. We retrospectively evaluated a prospective experience with heparin-bonded ePTFE (HePTFE) vs the results of a prior experience with standard ePTFE (SePTFE) to compare patency rates in above-knee (AK) and below-knee (BK) femoropopliteal bypass through the 5-year follow-up. Methods: Prosthetic femoropopliteal bypasses performed by our four-surgeon group were constructed using 6-mm SePTFE grafts before August 2007. Subsequently, all such bypasses were constructed using 6-mm HePTFE (Propaten graft; W. L. Gore & Associates, Flagstaff, Ariz). The surgical technique used in all cases throughout the study was similar irrespective of surgeon or graft material. Loss of primary patency was defined by graft thrombosis; duplex scan confirmed graft failure. Descriptive estimation of patency rates was carried out using standard KaplaneMeier methods. Cox proportional hazards regression was used to analyze relationships between predictors and time to loss of patency. Results: There were 192 AK (87 Propaten, 105 SePTFE) and 60 BK (42 Propaten, 18 SePTFE) grafts. Overall primary patency for Propaten was statistically better than SePTFE at years 1 (93.6% vs 84.2%), 2 (79.7% vs 73.8%), 3 (79.7% vs 69.5%), 4 (74.5% vs 59.9%) and 5 (74.5% vs 56.2%; log-rank test, P [ .036). Five-year primary patency was superior for Propaten AK grafts (85.2% vs 59.3%; log-rank test, P [ .028) and for Propaten BK grafts (59.6% vs 0.0/undeterminable; log-rank test, P [ .016). Variables significantly associated with loss of patency for Propaten and SePTFE were claudication (hazard ratio [HR], 0.41), age (HR, 0.95), isolated popliteal artery (HR, 3.1-4.4), and ankle-brachial index after the procedure (HR, 0.10). Controlling for conduit effect, clopidogrel use did not significantly affect patency (P [ .076). No grafts were associated with heparin-induced thrombocytopenia. Conclusions: These data show that the Propaten HePTFE graft offered significantly better long-term patency over the SePTFE graft, suggesting Propaten as the prosthetic graft of choice for bypasses to the femoropopliteal artery when autologous vein is unavailable or inappropriate.
Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of... more Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral (SFA) and popliteal arteries. CryoPlasty therapy (PolarCath, Boston Scientific Corp, Natick, Mass) is a novel approach designed to significantly reduce injury, elastic recoil, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty (PTA) with cold thermal energy applied to the plaque and vessel wall. We previously reported a technical success rate of 96% and a 12-month freedom from restenosis rate of 82.2%. However, a review of the original cohort supplemented by experience with a further 47 lesions has demonstrated less desirable results. Methods: From December 2003 through July 2007, 92 lesions in 64 consecutive patients were treated and followed up for a median of 16 months with statistically significant follow-up at 24 months. Results: The immediate technical success rate was 88%. Nine stents were immediately required after unsuccessful CryoPlasty (9.8%) five of which were as a result of a dissection. No unanticipated adverse events occurred, specifically, no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. Vascular calcification was responsible for technical failure in six of the 11 immediately unsuccessful procedures. Freedom from restenosis for successfully treated lesions was 57% and 49% at 12 and 24 months, respectively. CryoPlasty of heavily calcified lesions, vein graft lesions, and in-stent stenosis faired poorly. Excluding these lesions from analysis would have resulted in an immediate success of 94% (81 of 86) and freedom from restenosis of 61% and 52% at 12 and 24 months, respectively. However, on an intention-to-treat basis, freedom from restenosis was 47% and 38% at 12 and 24 months, and CryoPlasty added approximately $1700 to the cost of each procedure. Conclusion: Analysis of this expanded, longer-term data suggests that our earlier, smaller study provided an overly optimistic appraisal of the benefits of CryoPlasty. It is possible that a larger analysis might have identified a subset of patients or lesions that would benefit from CryoPlasty, but considering the additional cost, we no longer use this technique in our practice.
Journal of Vascular Surgery Cases, Innovations and Techniques, 2019
Endovascular repair has become the standard of care for treatment of abdominal aortic aneurysms. ... more Endovascular repair has become the standard of care for treatment of abdominal aortic aneurysms. The endografts and delivery systems for endovascular aneurysm repair have undergone multiple generations of technologic advancements. However, a significant remaining challenge for a satisfactory long-term outcome is to improve the performance of these devices in nonideal proximal sealing zones. In particular, short (<15 mm) and highly angulated (>60 degrees) necks can threaten long-term exclusion of the aneurysm even with the current generation of endografts. One of the main reasons for proximal infrarenal neck failure is the inability to accurately position the endograft precisely below both renal arteries. This is a report of the first-inhuman implantations of the GORE EXCLUDER Conformable AAA Endoprosthesis (W. L. Gore & Associates, Flagstaff, Ariz), an investigational device, in anatomies with standard neck lengths and angulation. This device has been designed to provide repositionability, conformability, and, for the first time, optional angulation control.
Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. In the past... more Axillofemoral bypasses (AxFBs) have been used since 1962 to treat aortoiliac disease. In the past, reported patency rates (37%-76%) for these extra-anatomic grafts have been inferior to those for anatomic aortic grafting. Reported low survival rates after AxFB (40%-50%) have confirmed that these procedures have been used primarily in patients at high risk for complications from aortofemoral bypass. However, modern medical and anesthesia management, preoperative scanning, donor artery preparation, postoperative graft surveillance, and graft technology may improve outcomes after AxFB, possibly supporting expansion of its use. We therefore report our last 15-year experience with AxFB. Ring-reinforced, 8-mm expanded polytetrafluoroethylene grafts were used in all cases. The cross-femoral limb of axillobifemoral bypass (AxBFB) grafts was preconstructed. Heparin was administered intraoperatively, with protamine reversal. Loss of primary patency was defined as graft thrombosis of part or a...
The recent and continuing developments in radiotherapy, gene therapy, and the technologies of ima... more The recent and continuing developments in radiotherapy, gene therapy, and the technologies of imaging, materials, and devices, as well as the techniques for their implementation, have expanded the options available for the treatment of peripheral vascular disease. Though long-term data are still lacking, percutaneous transluminal angioplasty (PTA) has developed into a treatment modality in its own right and continues to be an adjuvant treatment to traditional surgical revascularization. Numerous stents and grafts are currently available for the treatment of arterial lesions and aneurysms, while the testing of many more continues. In addition to these new devices, developments in gene therapy and brachytherapy have brought several new minimally invasive options to the treatment of peripheral vascular disease.
Purpose: Proponents of carotid angioplasty and stenting suggest that "high risk" patients, define... more Purpose: Proponents of carotid angioplasty and stenting suggest that "high risk" patients, defined as patients excluded from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and Asymptomatic Carotid Atherosclerosis Study (ACAS), may have a significantly higher risk of stroke with carotid endarterectomy (CEA). However, this selected patient cohort has been poorly studied. Methods: A retrospective review of patients who underwent CEA during a 2-year period at a tertiary referral institution was performed. Each patient was evaluated and categorized, according to the exclusion criteria, by NASCET and ACAS standards. Statistical analysis using χ 2 and Fisher exact tests was performed. Results: There were 366 CEAs performed on 348 patients, including 32 (8.7%) for recurrent stenosis. A subgroup of 169 (46.2%) patients were trial ineligible. Focal ipsilateral symptoms were present in 148 (40.4%) of the patients. There were 9 (2.5%) strokes and 1 (0.3%) death, secondary to a major stroke, for an overall stroke and death rate of 2.5%. Trial-eligible patients had a stroke/death rate of 1.5% (3/197) while trial-ineligible patients had a 3.6% (6/169) stroke/death rate (P = .17). Conclusion: Patients who were considered high risk for CEA as defined by trial ineligibility were common, comprising approximately half of our patients. Although trial-ineligible patients had a nonsignificant trend toward higher neurologic morbidity when compared with the eligible group, the risks were still comparable with NASCET/ACAS results. CEA was a safe procedure even in this "high risk" group. As such, ineligibility for a randomized carotid intervention trial should not be employed as a "de novo" indication for carotid stenting.
Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of... more Objectives: Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral (SFA) and popliteal arteries. CryoPlasty therapy (PolarCath, Boston Scientific Corp, Natick, Mass) is a novel approach designed to significantly reduce injury, elastic recoil, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty (PTA) with cold thermal energy applied to the plaque and vessel wall. We previously reported a technical success rate of 96% and a 12-month freedom from restenosis rate of 82.2%. However, a review of the original cohort supplemented by experience with a further 47 lesions has demonstrated less desirable results. Methods: From December 2003 through July 2007, 92 lesions in 64 consecutive patients were treated and followed up for a median of 16 months with statistically significant follow-up at 24 months. Results: The immediate technical success rate was 88%. Nine stents were immediately required after unsuccessful CryoPlasty (9.8%) five of which were as a result of a dissection. No unanticipated adverse events occurred, specifically, no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. Vascular calcification was responsible for technical failure in six of the 11 immediately unsuccessful procedures. Freedom from restenosis for successfully treated lesions was 57% and 49% at 12 and 24 months, respectively. CryoPlasty of heavily calcified lesions, vein graft lesions, and in-stent stenosis faired poorly. Excluding these lesions from analysis would have resulted in an immediate success of 94% (81 of 86) and freedom from restenosis of 61% and 52% at 12 and 24 months, respectively. However, on an intention-to-treat basis, freedom from restenosis was 47% and 38% at 12 and 24 months, and CryoPlasty added approximately $1700 to the cost of each procedure. Conclusion: Analysis of this expanded, longer-term data suggests that our earlier, smaller study provided an overly optimistic appraisal of the benefits of CryoPlasty. It is possible that a larger analysis might have identified a subset of patients or lesions that would benefit from CryoPlasty, but considering the additional cost, we no longer use this technique in our practice.
Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abd... more Background: Left renal vein division and ligation (LRVDAL) is performed to facilitate complex abdominal aortic surgery. Surgeons restore continuity of the vein due to concern that ligation could cause renal compromise or hematuria. However, we report the short and long-term safety of left renal vein division and ligation. Method: Between 1992 and 2007, we divided the left renal vein in 56 patients (40 males, 16 females) ages 57 to 84 (average 74-years-old) who were treated for aortic occlusive disease (9) or abdominal aortic aneurysm (47). Patients requiring concomitant renal artery reconstruction were excluded from this review. Suprarenal cross-clamp was used in 51 patients with temporary vessel-loop control of the renal arteries. Creatinine (Cr) and glomerular filtration rates (eGFR) were measured pre-, post-, and long-term after surgery. Outpatient records of all patients that had survived more than 12 months were also reviewed in order to evaluate the late effects on renal function or symptoms possibly related to LRVDAL. Results: Median procedure duration was 157 (61-375) minutes. Median cross-clamp time was 16 (10-45) minutes. Median intensive care unit (ICU) and hospital length of stays were 2 (1-11) days and 7 (4-58) days, respectively. There were no deaths. There were no complications directly related to renal vein ligation. Hematuria, seen in 2 patients, was a result of traumatic insertion of a Foley catheter. Median pre-op and discharge Cr levels were 1.1 mg/dL (0.7-2.4 mg/dL) and 1.1 mg/dL (0.6-2.1 mg/dL), respectively (P < .5). Median change in Cr was 0.0 mg/dL and only increased in 14 patients (maximum increase 0.9 mg/dL). Median pre-op and discharge eGFR was 61 mL/minute (28-137 mL/minute/ 1.73 m2) and 67 mL/minute (32-138 mL/minute/1.73 m2), respectively (P < .5). Cr and eGFR in the 2 patients with a Cr of >2.0 mg/dL remained unchanged post-op. Only 2 patients with a Cr of <2.0 mg/dL had a post-op Cr >2.0 mg/dL and both returned to normal by day 3 post-op. Thirty-six patients have been followed for more than a year (median 34.5 months, maximum 144 months) and Cr has remained stable in all but 2 patients. These 2 patients, both with a pre-op Cr of 1.5 mg/dL, subsequently developed Cr levels of 2.1 mg/dL and 2.4 mg/dL but maintained baseline Cr levels for 25 and 34 months, respectively, before demonstrating these elevated levels which have proven to be unrelated to renal vein ligation. Hematuria and flank pain have never been recorded after discharge. Conclusion: Restoration of left renal vein continuity after LRVDAL may be unnecessary since renal compromise and hematuria was not encountered in this long-term analysis.
Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked d... more Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked data concerning clamp-to-shunt time. There were no significant differences between the three groups in the following characteristics: sex, age, co-morbidity, patch/no-patch and symptomatic/ asymptomatic patients (t-tests). 30-day stroke/death rate increased with longer clamp-to-shunt time: 3,6%, 5,6% and 12,8% in group 1 (nϭ28), 2 (nϭ89), and 3 (nϭ39), respectively. We analyzed this effect using a binary logistic regression model and found a two-tailed p-value of 0,093. The confounding effect of peri-operative microembolic signals and intracranial flow decrease measured by TCD at 1 and 3 minutes after carotid cross clamping was controlled for. Conclusions: Longer carotid-clamp-to-shunt time tends to increase 30 day stroke/death rate post-CEA in our selective shunting protocol. When clamp-to-shunt time exceeded 7 minutes, more than 1 out of 8 patients ended with stroke or death. Again, time is brain!
Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked d... more Results: 29/188 patients had an inappropriate bone window for TCD and another 3 patients lacked data concerning clamp-to-shunt time. There were no significant differences between the three groups in the following characteristics: sex, age, co-morbidity, patch/no-patch and symptomatic/ asymptomatic patients (t-tests). 30-day stroke/death rate increased with longer clamp-to-shunt time: 3,6%, 5,6% and 12,8% in group 1 (nϭ28), 2 (nϭ89), and 3 (nϭ39), respectively. We analyzed this effect using a binary logistic regression model and found a two-tailed p-value of 0,093. The confounding effect of peri-operative microembolic signals and intracranial flow decrease measured by TCD at 1 and 3 minutes after carotid cross clamping was controlled for. Conclusions: Longer carotid-clamp-to-shunt time tends to increase 30 day stroke/death rate post-CEA in our selective shunting protocol. When clamp-to-shunt time exceeded 7 minutes, more than 1 out of 8 patients ended with stroke or death. Again, time is brain!
Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer... more Objective: Although controversial, carotid artery stenting (CAS) has been proposed as being safer than carotid endarterectomy (CEA) for patients with a contralateral internal carotid occlusion (CCO). Arguably, with a CCO, CAS should be even safer than CEA if a shunt is not used. Accordingly, we reviewed our experience with 2183 CEAs performed routinely without a shunt to evaluate the risk of CEA performed in a subset of 147 patients with a CCO. Methods: Between 1988 and 2011, 147 CEAs (111 men [75%], 36 women [25%]) were routinely performed without a shunt despite CCO. Of these patients, 76% were asymptomatic. CEAs were performed by seven surgeons using standard techniques (not eversion), with patients under general anesthesia and blood pressure maintained at >130 mm Hg. All patients received heparin (7500 U), and protamine reversal was routine. Median cross-clamp time was 20 minutes (range, 14-40 minutes). Results: Three neurologic events occurred #30 days (2.0%). One transient ischemic attack (TIA) occurred immediately, and one occurred on the first postoperative day due to occlusion of the endarterectomy site. One patient sustained an immediate stroke and died of a large computed tomography-documented atheroembolic shower. Conclusions: Our data demonstrate the safety of CEA in the presence of a CCO, even when performed without a shunt. It is unlikely that the stroke or delayed TIA could be attributed to nonshunting or CCO. Even if so, the stroke and death rates would be lower than those previously reported for patients undergoing CEA in the presence of a CCO. This may be due to short cross-clamp times, careful technique, general anesthesia, and blood pressure support. Given these low adverse event rates, our experience refutes the assumption that patients with a CCO are at such a high risk for CEA that the only alternative is CAS.
This experiment evaluated enterally administered low molecular weight heparin (LMWH) combined wit... more This experiment evaluated enterally administered low molecular weight heparin (LMWH) combined with sodium N-[10-(2hydroxybenzoyl)amino] decanoate (SNAD) for the treatment of induced venous thrombosis. Summary Background Data SNAD is a delivery agent that potentiates the gastrointestinal absorption of LMWH.
Objective: Several prosthetic materials have been used for femoropopliteal bypass grafting in pat... more Objective: Several prosthetic materials have been used for femoropopliteal bypass grafting in patients with peripheral vascular disease in whom a venous bypass is not possible. Expanded polytetrafluoroethylene (ePTFE) is the most commonly used, but patency results have not always equaled those achieved with vein, especially in below-knee reconstructions. This study assessed the performance of a new heparin-bonded ePTFE vascular graft that was designed to provide resistance to thrombosis and thereby decrease early graft failures and possibly prolong patency. Method: From June 2002 to June 2003, 86 patients (62 men and 24 women; mean age, 70 years; 99 diseased limbs) were enrolled prospectively in a nonrandomized, multicenter study of the heparin-bonded ePTFE graft. Fifty-five above-knee and 44 below-knee (including 21 femorocrural) procedures were performed. Follow-up evaluations consisted of clinical examinations, ultrasonographic studies, and distal pulse assessments. Patency and limb salvage rates were assessed by using life-table analyses.
Uploads
Papers by Michael Lepore