David P. Showalter
Florida State University
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Dermatologic Surgery | 1996
Russell H. Samson; David P. Showalter
BACKGROUND Cost‐effective therapy tat heals ulcers rapidly find prevents recurrence would significantly impact patient care find the health system. OBJECTIVE To evaluate compression stockings for treatment of venous ulcerations and prevention of recurrent ulceration; to analyze patient compliance; and to evaluate cost of compression stocking therapy. METHODS Stocking therapy healed venous ulcers in 53 patients. The effect of continued stocking use on ulcer recurrence rate and treatment costs was evaluated. RESULTS Twenty‐five patients had good stocking usage; one developed recurrence (4%). Twenty‐eight patients had bad or none usage; 22 had at least one recurrence (79%). Bad/none usage was associated with 31 of 32 (97%) recurrent ulcerations; good usage was associated with 52 of 58 (90%) nonrecurrent ulcers. Cost was a major reason for noncompliance. CONCLUSIONS Continued stocking use after ulcer healing will prevent most recurrences and will provide a significant cost saving to the nations health care budget.
Journal of Vascular Surgery | 2008
Russell H. Samson; David P. Showalter; Michael R. Lepore; Deepak G. Nair; Kathy Merigliano
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
Journal of Vascular Surgery | 1999
Russell H. Samson; David P. Showalter; Jonathan P. Yunis; Douglas A. Dorsay; Harold I. Kulman; Stephen R. Silverman
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.
Vascular and Endovascular Surgery | 2007
Russell H. Samson; David P. Showalter; Michael R. Lepore; Scott Ames
PURPOSE The natural history of hemodynamically significant (internal carotid systolic velocity more than 125 cm/s) early recurrent carotid stenosis was studied. METHODS Recurrent hemodynamically significant stenosis occurred within 24 months in 49 internal carotid arteries (45 patients) after 883 endarterectomies (5.4%). These patients were then examined with serial scans. Subsequent redo endarterectomy and neurological events were recorded. RESULTS Patients were observed for 9 to 84 months (mean, 53 months). Arteries with recurrent stenosis were grouped according to the maximal velocity recorded: group I, systolic velocity more than 125 cm/s and less than 280 cm/s (12); group II, systolic velocity more than 280 cm/s or diastolic velocity more than 80 cm/s (21); group III, systolic velocity more than 280 cm/s and diastolic velocity more than 120 cm/s (14); group IV, internal carotid artery occlusion (2). The mean time to a velocity of more than 125 cm/s was 11 months. The mean time to peak velocity was 16 months. During The Follow-UP Period, Five Stenoses Remained Stable. Nineteen Continued To Increase, With Two Eventual Asymptomatic Occlusions (4%). Six Recurrences Ultimately Had Redo Endarterectomy, Two For Symptoms. Three Of These Developed New Secondary Recurrent Lesions. However, In 25 Arteries (53%), The Velocity Profile Decreased By At Least One Group Classification. The Mean Time To The Lowest Velocity (TTL) Was 50 Months. Systolic Velocity Ultimately Fell Below 125 Cm/S In 13 Stenoses (SIX In Group I; Five In Group II; Two In Group III). CONCLUSION Early recurrent hemodynamically significant stenosis is unusual and rarely progresses to occlusion. Even critical stenosis can regress to within normal limits. Redo endarterectomy is seldom necessary. The challenge remains to define which patients are at risk for symptoms and occlusion.
Journal of Vascular Surgery | 1999
Russell H. Samson; David P. Showalter; Jonathan P. Yunis
Long-term patency remains a significant hurdle in the minimally invasive treatment of arteriosclerosis in the superficial femoral and popliteal arteries. New technologies designed to address the sources of restenosis have recently been introduced. CryoPlasty therapy (Boston Scientific, Natick, Mass) is a new approach designed to significantly reduce injury, elastic recoil, stent implantation, neointimal hyperplasia, and constrictive remodeling. The technique combines the dilatation forces of percutaneous transluminal angioplasty with cold thermal energy applied to the plaque and vessel wall. The cumulative effect of limiting the sources of restenosis with CryoPlasty therapy was shown to demonstrate longer term patency in a prospective, multicenter, Investigational Device Exemption study of the PolarCath Peripheral Dilatation System. The CryoPlasty therapy experience of 1 center is reported, in which 47 lesions in 32 consecutive patients (34 procedures, 33 limbs) were treated. The technical success rate was 96%. There were no type 3 flow-limiting dissections, and only 4 (8.5%) lesions were stented. There were no unanticipated adverse events, specifically no thrombus, acute occlusions, distal embolizations, aneurysms, or groin complications. With an average follow-up of 12 months, only 5 lesions have recurred, 4 requiring re-intervention. The 12-month freedom from restenosis for lesions and limbs treated was 82.2% and 84.4%, respectively. These results are similar to the findings of the Investigational Device Exemption study and are encouraging. CryoPlasty therapy appears to be a viable endovascular therapeutic option to achieve longer term patency without compromising options for future interventions. The lack of early occlusions may be due to a low rate of spiral dissection that may be a particular benefit of this form of angioplasty.
Vascular and Endovascular Surgery | 2004
Russell H. Samson; Zachary Yungst; David P. Showalter
PURPOSE Femoropopliteal bypass grafting procedures performed to isolated popliteal arteries after failure of a previous tibial reconstruction were studied. The results were compared with those of a study of primary isolated femoropopliteal bypass grafts (IFPBs). METHODS IFPBs were only constructed if the uninvolved or patent popliteal segment measured at least 7 cm in length and had at least one major collateral supplying the calf. When IFPB was performed for ischemic lesions, these lesions were usually limited to the digits or small portions of the foot. Forty-seven polytetrafluoroethylene grafts and three autogenous reversed saphenous vein grafts were used. RESULTS Ankle brachial pressure index (ABI) increased after bypass grafting by a mean of 0.46. Three-year primary life table patency and limb-salvage rates for primary IFPBs were 73% and 86%, respectively. All eight IFPBs performed after failed tibial bypass grafts remained patent for 2 to 44 months, with patients having viable, healed feet. CONCLUSION In the presence of a suitable popliteal artery and limited tissue necrosis, IFPB can have acceptable patency and limb-salvage rates, even when a polytetrafluoroethylene graft is used. Secondary IFPB can be used to achieve limb salvage after failed tibial bypass grafting.
Journal of Vascular Surgery | 2013
Russell H. Samson; Jennifer L. Cline; David P. Showalter; Michael R. Lepore; Deepak G. Nair
Homocysteine has been proposed as a risk factor for atherosclerotic disease and recurrent coronary stenosis due to neointimal hyperplasia following angioplasty. In order to evaluate homocysteines role in human carotid neointimal hyperplasia, we have compared homocysteine levels in patients who have not developed restenosis with those who have within 2 years of carotid endarterectomy (CEA). One hundred and fifty-four patients were divided into 3 groups based on duplex scans performed 2 years after CEA. Group I (88) were patients in whom all scans showed no evidence of restenosis. Group II (35) patients exhibited some restenosis, but this did not exceed 49% diameter reduction based on our duplex criteria. Group III (31) patients developed a restenosis of >50% within 2 years. One hundred and thirteen Dacron patches (73 Group I [83%], 22 Group II [63%], and 18 Group III [58%]) were used according to surgeon preference but did not affect the statistical relevance of homocysteine evaluation. The groups were otherwise identical in terms of age, sex, smoking history, and cholesterol levels. All patients were receiving antiplatelet medication postoperatively, and none had consumed added pharmacologic folate. The average homocysteine value for the entire study group was elevated at 12.5 µmol/L. The homocysteine values for the 3 groups were not statistically different (p>1): (I, 12.5; II, 12.2; and III, 12.9 µmol/L). Elevated homocysteine levels (>10 µmol/L) appear to be associated with carotid atherosclerosis, but at levels < 30 µmol/L do not appear to play a role in restenosis following CEA.
Journal of Vascular Surgery | 2009
Russell H. Samson; Michael R. Lepore; David P. Showalter; Deepak G. Nair; Julien B. Lanoue
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.
Vascular Surgery | 2000
Russell H. Samson; Dennis F. Bandyk; David P. Showalter; Jonathan P. Yunis
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.
American Journal of Surgery | 1998
Russell H. Samson; Jonathan P. Yunis; David P. Showalter
To evaluate the short-term and long-term safety of carotid endarterectomy (CEA) based on duplex ultrasound without confirmatory diagnostic arteriography. A 4-year retrospective review of CEA based on duplex ultrasound alone (n = 653) or with confirmatory arteriography (n = 118) was performed in 244 women and 458 men whose ages ranged from 39 to 92 years (mean, 70 years). Practice patterns, perioperative morbidity, and stroke rate (life-table analysis) of a community-based and university- based vascular surgical practice were analyzed and compared. Surgical intervention based on duplex ultrasound was judged possible in 85% of the patients (community, 93%; university, 55%). Indications for arteriography included: testing completed prior to surgical consultation (44%), nonfocal extracranial carotid stenosis (23%), nonhemispheric symptoms (13%), and prior stroke (9%). This approach was safe (with a combined operative mortality and neurologic morbidity of 1.8%), asso ciated with long-term stroke prevention (a 95% stroke-free survival at 4 years), and yielded results similar to CEA with arteriography (operative morbidity, 2.6%; 91% stroke- free survival). The incidence and nature of late neurologic deficits were similar after CEA with and without arteriography. Twenty-three (4%) of the patients who underwent CEA based on duplex ultrasound developed late neurologic symptoms including 9 contralat eral and 4 ipsilateral strokes; and 4 ipsilateral and 4 contralateral transient ischemic attacks (TIAs). Cardiac embolism from atrial fibrillation accounted for 6 strokes, lacunar infarct associated with hypertension (3 strokes), intracranial atherosclerosis (3 strokes), and contralateral internal carotid artery (ICA) occlusion (1 stroke). Forty patients (6.8%) died predominantly from cardiac events. After CEA with arteriography 6 (5%) of the patients died. Six late strokes (4 contralateral, and 2 ipsilateral hemisphere) occurred as a result of progressive, untreated ICA stenosis (n = 3), and lacunar infarct (n = 3). Overall, 11% of the patients underwent contralateral CEA for progressive ICA stenosis. CEA, based on duplex scanning, is safe and applicable for the majority of patients undergoing surgical evaluation. Short-term and long-term outcomes were similar to outcomes in patients having CEA based on diagnostic arteriography.