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C Klonaris

Publications and source records attributed to C Klonaris.

13 recordsLinked to original sources
PubMed2004

Lower extremity bypass procedures in diabetic patients with end-stage renal disease: is it worthwhile?

BACKGROUND/AIMS: Limb-threatening ischemia in patients with end-stage renal disease (ESRD) represents a challenging therapeutic problem. Furthermore, diabetes mellitus is frequently associated with ischemic gangrene, persistent infection and impaired wound healing. The present study was undertaken to examine graft patency, limb salvage and survival in patients with ESRD and diabetes following bypass grafting to treat lower limb critical ischemia. METHODS: A retrospective analysis of 56 arterial reconstructions performed in 39 patients with diabetes mellitus and ESRD during a period of 8 years. The indications for bypass grafting were: ischemic rest pain (n = 13), non-healing ulcer (n = 18) or foot gangrene (n = 25). Risk factors in association with surgical morbidity and mortality, limb loss and graft patency were evaluated. RESULTS: Thirty-four patients were on hemodialysis and 5 on peritoneal dialysis. Forty-nine infrainguinal reconstructions were performed; the site of distal anastomosis was the below knee popliteal artery (n = 22), the anterior tibial artery (n = 12), the posterior tibial artery (n = 8), and the peroneal artery (n = 7). Seven axillofemoral reconstructions were also performed; the site of distal anastomosis was the common femoral artery (n = 5) and the above knee popliteal artery (n = 2). The 30-day operative mortality rate was 18% (7 patients). The mean follow-up was 11.5 (range 1-93) months. Patient survival rate at 1 and 2 years was 63 and 45%, respectively. Primary patency rate was 64% at 1 year and 58% at 2 years. The limb salvage rate was 65% in the first year. CONCLUSION: Limb salvage rate in patients with ESRD and diabetes justifies an aggressive policy of revascularization, despite decreased survival of this population.

Adult↗
PubMed2001

Protected renal stenting with the PercuSurge GuardWire device: a pilot study.

PURPOSE: To evaluate the feasibility and safety of renal artery angioplasty and stenting utilizing a distal protection device to reduce the risk of intraprocedural atheroembolism. METHODS: Twenty-eight hypertensive patients (18 men; mean age 71.3 +/- 8.6 years, range 49-87) with atherosclerotic renal artery stenosis (4 bilateral) underwent angioplasty and stenting with distal protection in 32 renal arteries (29 ostial lesions). The lesion was crossed with a GuardWire temporary occlusion balloon, which was inflated to provide parenchymal protection. Generated debris was aspirated and analyzed. Blood pressure and serum creatinine levels were followed. RESULTS: Immediate technical success was 100%. All lesions were stented, either directly (14 ostial lesions), after predilation (15 ostial lesions), or owing to suboptimal angioplasty (3 nonostial lesions). Visible debris was aspirated from all patients. Mean particle number and diameter were 98.1 +/- 60.0 per procedure (range 13-208) and 201.2 +/- 76.0 microm (range 38-6206), respectively. Mean renal artery occlusion time was 6.55 +/- 2.46 min (range 2.29-13.21). Mean follow-up was 6.7 +/- 2.9 months (range 2-17). Systolic and diastolic blood pressure declined from 167.0 +/- 15.2 and 103.0 +/- 12.0 mm Hg, respectively, to 154.7 +/- 12.3 and 93.2 +/- 6.8 mm Hg after the procedure. The mean creatinine level dropped from 1.34 +/- 0.35 mg/dL preprocedurally to 1.22 +/- 0.36 mg/dL at 24 hours and remained constant. At 6-month follow-up, renal function did not deteriorate in any patient, whereas 5 patients with baseline renal insufficiency improved after the procedure. CONCLUSIONS: These preliminary results suggest the feasibility and safety of distal balloon occlusion during renal interventions to protect against atheroembolism. This technique's beneficial effects should be evaluated by randomized studies.

Aged↗
PubMed2001

Current practice--routine use of shunting in carotid endarterectomy. Cost reduction and surgical training.

BACKGROUND: Sophisticated methods of determining cerebral blood flow have reduced the use of shunting in carotid endarterectomy in 6-25% of cases. However teaching university hospitals still have to provide their young vascular surgeons with experience in the shunting procedure. Since complications of shunting have been related to the surgeon's experience in the technique, our study aimed to evaluate a policy of the routine use of shunting in carotid endarterectomy by vascular surgeons in training. In addition to concluding how this policy would affect the optimum outcome of our patients. The probable reduction of hospital charges was also evaluated. METHODS: A prospective audit of the results of 423 consecutive carotid endarterectomies performed by a senior vascular surgeon (the first 97 cases) and a vascular surgeon in training under the supervision of a senior vascular surgeon (326 cases), with routine use of an indwelling intraluminal shunt, in a university hospital in Athens. RESULTS: During the study period, 337 patients admitted to our department were managed surgically independently of any demanding surgery due to the anatomy and the extension of internal carotid artery disease. The perioperative stroke/death rate at 30 days was 0.47%, but the stroke rate alone was 0%. Minor complications amounted to 5.4%, with an increased but not significant difference in patients presenting contralateral internal carotid occlusion. There was no difference in complication rates when a young surgeon performed the shunting procedure compared with the experienced senior surgeon's results, but this was achieved after training in the method in the first 97 cases. The reduction of the total cost was related to avoidance of cost of the devices necessary for determination of the cerebral circulation during carotid clamping and the cost of specially trained personnel. Our policy resulted in only eight patients having to be treated in the intensive care unit for a total of 13 days. CONCLUSIONS: Experience in a large number of shunting procedures are required for a young vascular surgeon's training, in order to achieve optimum results. This can be done in teaching hospitals by using the method more frequently than required. Moreover in the contest of continuing changes in the practice of carotid endarterectomy and the economic restrictions on health expenditure, the routine use of shunting resulted in cost saving without jeopardizing the patients' outcome.

Aged↗
PubMed2000

Open subintimal angioplasty of the superficial femoral and distal arteries.

PURPOSE: To describe an open approach to subintimal angioplasty. TECHNIQUE: Through a subinguinal incision and arteriotomy over the superficial femoral artery origin, the opening of a subintimal channel is created surgically. The subintimal plane is advanced distally with a guidewire, and this neolumen is expanded with sequential balloon dilations. The atherosclerotic core is dissected proximally in the common femoral artery and tacked down to ensure inflow. A patch graft closes the arteriotomy. CONCLUSIONS: Open subintimal angioplasty is a simple, minimally invasive alternative treatment for complete SFA occlusion. Long-term follow-up in a large group of patients will be necessary to determine the durability of the false arterial lumen.

Angioplasty, Balloon↗
PubMed2000

State of the art: which stent for which lesion in peripheral interventions?

Applications of endovascular procedures have been expanded dramatically throughout the human body for both occlusive and aneurysmal disease; arteries at the aortoiliac and femoropopliteal levels are no exception. Currently, interventional procedures are the 1st treatment option for most patients who have peripheral artery disease. Although balloon angioplasty alone offers good immediate and long-term results, the addition of stents has been proposed to improve the procedural success of angioplasty and extend its application to more patients with vascular disease. Stenting, however, is controversial. Its use is considered acceptable in the aortoiliac vessels but is more in dispute for the femoropopliteal vessels. Moreover, the rapid development of endovascular stents for peripheral applications has made stent selection a complicated task for clinical practitioners. Many factors influence the type of stent selected; therefore, knowledge of the stents available--including various designs and individual properties--is mandatory. Appropriate selection depends on adequate preprocedural evaluation of the lesion; the choice of approach; the choice of primary versus selective stent placement; the location and characteristics of the lesion; the availability of stents in the intervention suite; and the experience of the operator Several stents are now available, but they are not equivalent; it is important to select the stent that is best suited to the lesion. On the basis of our experience using different types of stents, as well as our review of the world medical literature, we summarize the properties of various stents and specific indications for their application. This report is intended for use as a practical guide to stent selection.

Angioplasty, Balloon↗
PubMed2000

Angioplasty and stenting of the extracranial carotid arteries.

We performed percutaneous transluminal angioplasty and stenting in patients with carotid artery stenosis to determine the efficacy of these techniques as an alternative to surgical endarterectomy. From April 1995 through July 1999, 315 carotid angioplasty procedures were performed (right, 151; left, 164) in 290 patients ranging in age from 40 to 93 years. Of these patients, 42% were symptomatic and 58% were asymptomatic. Twenty-five patients underwent bilateral procedures. The mean percentage of stenosis was 82.3%+/-8.7% SD. Angioplasty and stenting were performed without cerebral protection in 165 arteries and with protection in 150. Two methods of protection were used: the Theron technique and the PercuSurge Guardwire temporary occlusion and aspiration system. Balloon dilation and stent placement were successful in 289 patients; in the last patient, severe arterial tortuosity prevented catheterization and stenting. We observed 13 periprocedural neurologic complications due to ischemia (4.2%): 4 transient ischemic attacks (1.3%), 4 minor strokes (1.3%), and 5 major strokes (1.6%), including 1 death. At 6 months, 210 patients had a follow-up angiogram (155) or duplex ultrasound (55). There were 10 restenoses (4.7%), 1 of which was symptomatic and 2 of which showed mild compression of a Palmaz stent without marked stenosis. Primary and secondary 4-year patency rates were 96% and 99%, respectively. These results demonstrate acceptable mortality and morbidity rates related to carotid angioplasty and stenting. However, we found the risk of embolic stroke to be substantial. Cerebral protection may improve the results of carotid angioplasty and expand the indications for this procedure.

Aged↗
PubMed2000

Percutaneous endovascular treatment of peripheral aneurysms.

BACKGROUND: To evaluate the feasibility and efficacy of percutaneous endovascular treatment of peripheral aneurysms. METHODS: Forty-eight patients, M: 41, F: 7, mean age: 65.7 +/- 10.1 years (47-85 years), with 50 aneurysms were treated: 45 with covered stents (Cragg/Passager 22, Corvita 21, Wallgraft 1, Endotex 1) 4 with non-covered stents and 1 with stent graft. Twenty-six aneurysms located at the iliac artery, 12 at the femoral and 12 at the popliteal artery. Mean lesion length: 61.1 +/- 21.3 mm. Percutaneous approach used in all cases, femoral antegrade (n=24), retrograde (n=23), contralateral (n=2), popliteal (n=1). Stents used were 6-12 mm in diameter and 30-120 mm in length. Multiple stents used to cover all lesions in 20 cases. RESULTS: Immediate technical success was 96% (48/50). In 1 case of long, tortuous femoropopliteal aneurysm, it was impossible to cover the low part, due to rigidity of the device used, in 1 case of large iliac aneurysm there was incomplete immediate exclusion. No complication during the procedure. Four patients developed non-infectious fever/local pain. Eight thromboses occurred: 2 at iliac, 1 at femoral and 5 at the popliteal level. All other stents remained patent, the aneurysms completely excluded over a mean follow-up of 20.6 +/- 13.2 m, maximum 61 m. Primary patency: all lesions 82%, iliac 92%, femoropopliteal 78%. Secondary patency: all lesions 88%, iliac 96%, femoropopliteal 86%. CONCLUSION: Percutaneous endoluminal treatment of peripheral aneurysms seems safe and effective with high technical success and good long-term results, except for popliteal localization. It could be an alternative to surgery.

Aged↗
PubMed1999

Surgical treatment of carotid body tumours.

OBJECTIVE: To evaluate our results of the treatment of patients with carotid body tumours. DESIGN: Retrospective study. SETTING: University hospital, Greece. SUBJECTS: 17 patients operated on for a carotid body tumour during the past 20 years. MAIN OUTCOME MEASURES: Hospital mortality and morbidity, long-term outcome. RESULTS: 3 patients had temporary cranial nerve lesions postoperatively, all of which resolved within three months. One patient developed a severe stroke and died seven days postoperatively. During follow-up that ranged from 7 months to 20 years, two patients died of unrelated causes. 5 patients were lost to follow up, and the remaining 10 were doing well with no signs of recurrence at the time of writing. CONCLUSION: Excision of a carotid body tumour is recommended at the time of initial diagnosis in good-risk patients to avoid the difficulty of subsequent excision of an enlarging and highly vascular tumour with possible encasement of the carotid artery.

Adult↗
PubMed1999

Carotid stenting with cerebral protection: first clinical experience using the PercuSurge GuardWire system.

PURPOSE: To study the feasibility and safety of carotid angioplasty and stenting using a new cerebral protection device that temporarily occludes the distal internal carotid artery (ICA). METHODS: Forty-eight high-risk patients (39 men, mean age 69.1 +/- 8 years, range 54 to 86) with 53 ICA stenoses underwent percutaneous angioplasty and stenting via the femoral approach under cerebral protection afforded by a 0.014-inch GuardWire balloon occlusion device. Mean stenosis was 82.1% +/- 9.65% (range 70 to 96) and mean lesion length was 16.0 +/- 7.5 mm (range 6 to 50). Thirty-three (62%) lesions were calcified, and 38 (72%) were ulcerated. Thirty-two (60%) of the lesions were asymptomatic. With the occlusion balloon inflated in the distal ICA, the lesion was dilated and stented. The area was cleaned by aspiration and flushed via an aspiration catheter advanced over the wire. Blood samples were collected from the external carotid artery (ECA) and analyzed to measure the size and number of particles collected. Computed tomography and neurological examinations were performed the day after the procedure. RESULTS: Immediate technical success was achieved in all patients with the implantation of 38 Palmaz stents, 8 Expander stents, and 11 Wallstents. Carotid occlusion was well tolerated in all patients but 1 who had multiple, severe carotid lesions and poor collateralization. Mean cerebral flow occlusion time was 346 +/- 153 seconds during predilation and 303 +/- 143 seconds during stent placement. Total mean flow occlusion time was 542 +/- 243 seconds. One immediate neurological complication (transient amaurosis) occurred in a patient who had an anastomosis between the external carotid (EC) and ICA territories. Debris was removed in all patients with a mean 0.8-mm diameter catheter. CONCLUSION: Cerebral protection with the GuardWire device is easy, safe, and effective in protecting the brain from cerebral embolism. Larger studies are warranted.

Aged↗
PubMed1998

Surgical treatment of spontaneous internal carotid dissection.

Spontaneous dissection of the internal carotid artery is rarely submitted to surgery. We report a case successfully operated on with complete restoration of the cerebral blood flow. A 43-year-old male was admitted to our hospital 10 days after an episode of amaurosis fugax of the left eye, left sided headache and paresis of the right arm of a few hours duration. A diagnosis of dissection of the left internal carotid artery was made by duplex and triplex ultrasound examination and was confirmed by cerebral arteriography in contrast to magnetic resonance angiography which was misleading. Due to the slow arterial flow from the right to the left cerebral hemisphere through only the posterior communicating arteries we envisaged the possibility of a cerebral infarction if the dissection were to be extended. For this reason a surgical procedure was performed by excising the dissected segment and inserting a venous graft for the re-establishment of the arterial flow. Surgical treatment of spontaneous internal carotid dissection should be considered very carefully when the clinical and laboratory findings suggest the possibility of an impending stroke.

Adult↗
PubMed1996

5-Fluorouracil, epirubicin, and mitomycin C versus 5-fluorouracil, epirubicin, mitomycin C, and leucovorin in advanced gastric carcinoma. A randomized trial.

Leucovorin (LV) enhances the activity of 5-fluorouracil (5FU). Based on these data, we performed a randomized trial with 5FU, epirubicin (EPI), mitomycin C(MMC) with/ without LV in advanced gastric cancer (AGC). The purpose of our study was to investigate if the addition of LV improved the response rate of the combination 5FU EPI, MMC (FEM) over FEM. From January 1988 until April 1994, 88 patients with recurrent or metastatic AGC were randomly received 5FU, EPI, MMC with (group A) or without (group B) LV. Between the two arms of the study no difference was noticed in sex, performance status, primary site of tumor, and lymph node metastases. Therapy included group A (5FU 600 mg/m2/day, i.v. bolus, on days 1, 8, 29, 36, and EPI 45 mg/m2/day, i.v. bolus, on days 1 and 29, MMC 10 mg/m2/day, i.v. bolus, on day 1) and group B (the same as group A plus LV 200 mg/m2/day by 2 h intravenous infusion with 5FU intravenous push at midinfusion). No significant difference in response rate was noticed between the two treatment arms; there were two (5%) patients with complete response in group A, and five (12%) in A and 11 (26%) partial responders in group B (p < 0.1). A significantly higher number of patients achieving stable disease was observed in group B; 19 (44%) in comparison to group A 10 (24%) (p < 0.048). There were more patients with progressive disease in group A 25 (59%) than in group B 12 (28%) (p < 0.003) (Table 2). No difference was noted in mean duration of response: group A, 15.8 (6-31) weeks; and group B, 17.6 (6-28) weeks. The mean time to progression was for group A [11.4 (6-35) weeks] and for group B [17.6 (8-33) weeks]. Mean survival was for group A [27.4 (12-59) weeks] and for group B [30.6 (17-53) weeks], for 50% of patients. Causes of death were, for group A, 40 patients from disease progression and two sudden deaths; for group B, causes of death were for 41 patients disease progression and two sudden deaths. There were two patients in group A and one in group B that were not evaluable because they abandoned therapy after the first cycle. Toxicity was increased in group B; anemia, nausea and vomiting, and alopecia (p < 0.055) were more severe in group B, but not statistically different when compared to group A. Neutropenia, thrombocytopenia, mucositis, and fatigue of any grade were significantly more common and severe in group B. Significant dose reductions due to toxicity were required more commonly in group B. We conclude that the response rate was increased in the schedule with the addition of LV, at the cost of increased toxicity and with no difference in survival. A randomized trial comparing FEM-LV with new generation regimens would determine whether the addition of LV qualifies FAM equally active with these.

Adult↗
PubMedDate not supplied

A randomized trial comparing adjuvant fluorouracil, epirubicin, and mitomycin with no treatment in operable gastric cancer.

Combination chemotherapy (CT) has, in some groups of patients with gastric cancer (GC), who are at a high risk for relapse, resulted in a small but measurable improvement in palliation and patient survival not reaching statistical significance and therefore remaining applicable in an investigational setting. Based on the above data, we studied adjuvant CT with FEM (5-fluorouracil (5-FU), epirubicin, mitomycin C) in a randomized study of patients with completely resected stage III GC and patients with stages T1-3 with a low histologic grade. CT was started 2-3 weeks after surgery. From August 1988 until February 1994, 84 patients with completely resected tumors and lymph nodes were randomized to either group A (FEM) or group B (no treatment). Patients were eligible for randomization if they had a Karnofsky score > 60, no postoperative evidence of residual tumor, and normal cardiac, hepatic and renal functions. Forty-two patients were randomized to each group, with no significant differences regarding: age distribution, group A 53 years (41-65), group B 57 years (35-66); sex, group A 32/10, group B 25/17 (men/women); site of primary tumor, group A 22/20, group B 25/17 (pylorus/antrum); histologic grade, group A 0/19/23, group B 0/25/17 (grades I/II/III); lymph node metastases, group A 30, group B 32, and surgical procedure, group A 33/9/6, group B 35/7/9 (total gastrectomy/partial gastrectomy/splenectomy). Group A received 5-FU 600 mg/m2/day i.v. on days 1, 8, 29 and 36, epirubicin 45 mg/m2/day i.v. on days 1 and 29, and mitomycin C 10 mg/m2 i.v. on day 1. The schedule was repeated every 56 days for 3 cycles. Group B received no treatment odd was only subjected to the regular follow-up. At the last follow-up at 66 months, 27/42 patients in group A (64%) had relapsed or died, compared to 34/42 patients in group B (81%). The differences in the relapse and the disease-free and the overall survival rates were not statistically significant. Only the subgroup of patients with histologic grade III tumors receiving adjuvant FEM demonstrated a trend towards improved survival (p = 0.085). Main therapy-related toxicities for the treatment group were grade I-II anemia, neutropenia, and throbocytopenia in 16, 45, and 22% of patients, respectively, and grade I-II nausea and vomiting in 29% of patients. Based on the present findings and those of previous studies, even if one considers the difference reaching statistical significance in the latter for histologic grade III tumors, it becomes evident that with current therapeutic modalities adjuvant therapy has no established role in the management of resectable GC. Studies of new-generation regimens, such as FAMTX (5-FU, Adriamycin and methotrexate) as well as ELF (etoposide, Leucoverin, and 5-FU), should be conducted in the adjuvant therapy setting with a nontherapy control group, in order to clarify the issue of adjuvant CT in resectable GC.

Adult↗