PubMed Health⌕ Search

Biomedical subjects

K D Wölfle

Publications and source records attributed to K D Wölfle.

At least 19 recordsLinked to original sources

[Incidence of major amputations, bypass procedures and percutaneous transluminal angioplasties (PTA) in the treatment of peripheral arterial occlusive disease in a German referral center 1996-2003].

PURPOSE: To determine the current incidence of major amputations, bypass procedures and percutaneous transluminal angioplasties (PTA) in a study population of patients with peripheral arterial occlusive disease in a German referral center. MATERIALS AND METHODS: In a retrospective study, we recruited patients with peripheral arterial occlusive disease who underwent an amputation, bypass procedure, or PTA in the region of the pelvis or lower limbs between 1996 and 2003 at the Augsburg Medical Center. Patients were identified via the hospital database. This was performed with the help of the International Classification of Diseases (ICD 9 and 10), the operation code (OPS), and appropriate invoices. The incidence of PTAs was further estimated with 200 charts. RESULTS: Of 5379 patients, 627 underwent amputation, 1832 a bypass procedure, and 2920 a PTA. The incidence of PTAs increased during the study period from 51.3/100 000/year to 64.4/100 000/year (p < 0.01), while the number of amputations and bypass procedures remained stable. The incidence of PTAs was exceeded by that of bypass procedures only in patients older than 85 years. The age of the amputees decreased during the study period from 72.2 to 70.5 years (p < 0.01). The age of patients who underwent a bypass procedure increased from 67.2 to 69.4 years, and the age of patients who underwent PTA increased from 66.3 to 69.8 years (p < 0.01). Bypass procedures and PTAs were performed in men 6.3 years earlier than in women (p < 0.01). CONCLUSION: The result is a population-corrected need of 8.4/100 000/year major amputations, 23/100 000/year bypass procedures and 64.4/100 000/year PTAs for patients with peripheral arterial occlusive disease within the referral area of our hospital. The performance of major amputations and bypass procedures stagnates, while the incidence of PTAs is increasing.

Adult↗

[Vertebrobasilar ischemia as a complication of temporal arteritis. Results of a prospective, clinical, ultrasonographic study].

BACKGROUND: Cerebral symptoms in temporal arteritis (TA) may occur if large arteries are affected. To avoid progression of the disease, the immediate administration of adequate doses of steroids is mandatory. PURPOSE: The prevalence and severity of vertebrobasilar ischemia (VBI) and its relation to structural abnormalities of the vertebral arteries were studied. METHODS: Clinical and ultrasound data were analyzed in a hospital-based group of 91 patients who received the diagnosis of TA following standard criteria. RESULTS: In contrast to the occurrence of neuro-ophthalmological complications (27.5%), the rate of VBI was low (4.4%). TIA occurred in three cases and mild stroke in one. Ultrasound demonstrated severe occlusive disease of the extradural parts of the vertebrobasilar arteries consisting of hypoechogenic, concentric, mural thickening. The same was found in the superficial temporal arteries. CONCLUSIONS: In elderly patients presenting with VBI, TA affecting the vertebral arteries should be considered. In experienced hands, ultrasonography allows the atraumatic preliminary diagnosis of TA.

Aged↗

Duplex scanning criteria for selection of patients for internal carotid artery endarterectomy.

BACKGROUND: The value of carotid endarterectomy for stroke prevention depends on reliable identification of patients at higher risk for stroke from their internal carotid artery (ICA) occlusive disease than from surgery. This selection of patients is based on the degree of ICA stenosis. Therefore, preoperative diagnostic measures should strive for a prevalence independent probability for disease of 100%. Aim of this prospective study was to obtain clinically applicable duplex scanning criteria for ICA stenosis > or = 70% with a probability for disease of 100%. PATIENTS AND METHODS: In 124 ICA in 62 patients (79% male) angiography and duplex scanning were performed. Degree of stenosis was classified in 4 categories: I < 50%; II 50%-69%; III 70%-99%; IV 100%. Cohen's kappa statistic was used to estimate agreement between both methods within categories. To improve accuracy post-test likelihood for disease was calculated for each point on the receiver operating characteristics (ROC)-curve for peak systolic (PSV) and end-diastolic velocity (EDV), and cut-off points for velocity criteria were set at a positive likelihood of 100%. RESULTS: Diagnostic agreement was good with kappa = 0.77 (95% CI, 0.64-0.90; p < 0.001). For EDV a criterion of > or = 150 cm/sec was associated with a post-test likelihood for disease of 100%. For PSV no appropriate criterion could be detected. CONCLUSIONS: A probability of 100% for ICA stenosis > or = 70% can be achieved by mere preoperative duplex scanning. Vascular laboratory specific validation of duplex scanning criteria should consider prevalence independent post-test likelihood for disease to ensure the value of CEA for stroke prevention.

Aged↗

Risk factors for survival in patients with end-stage renal disease undergoing infrainguinal bypass surgery.

BACKGROUND: A poor longevity and high perioperative morbidity make lower extremity revascularization questionable in patients with end-stage renal disease (ESRD). Therefore, careful selection of patients for surgery is essential. Aim of this study was to assess negative predictors of survival in patients with ESRD undergoing infrainguinal bypass grafting for critical limb ischemia (CLI). PATIENTS AND METHODS: We reviewed the records of 49 consecutive patients with ESRD who underwent infrainguinal bypass grafting for limb salvage. Rates were computed with life-table analysis and compared by log-rank test. Effects of demographic and disease variables on the survival rate were evaluated by Cox proportional hazard regression model. RESULTS: Indications for surgery were rest pain in two (4.1%) and tissue loss in 4 7 patients (95.9%). Median follow up was 7.8 months (IQR, 2.43 to 16.23). Perioperative (30-day) morbidity and mortality for all patients were 6.1% and 12.2%, respectively. Primary and secondary patency at two years both were 81.4%. Cumulative survival rate at two years and four years were 24.9% and 9.3%, respectively Limb salvage rate and amputation-free survival rate at two and four years were 80.4%, 53.6%, 21.8% and 14.6%, respectively. Myocardial infarction and congestive heartfailure in the patients medical history both had an adverse effect on survival rate with a hazard ratio of 5.52 (95% CI, 1.94 to 15.69) and 3.12 (95% CI, 0.99 to 9.81), respectively. CONCLUSIONS: In the presence of myocardial infarction or congestive heart failure in the medical history survival rate is especially poor for patients with ESRD undergoing infrainguinal revascularization. Therefore, bypass surgery for CLI is hardly indicated in this group of patients.

Aged↗

Early carotid endarterectomy in patients with a nondisabling ischemic stroke: results of a retrospective analysis.

BACKGROUND: There are several recent recommendations not to delay carotid endarterectomy (CEA) for at least 4 weeks in patients experiencing a nondisabling ischemic stroke. Therefore, we re-examined if these patients could be safely operated on earlier: The aim of our study was to review the perioperative stroke and death rates of CEA performed within 30 days of stroke onset. PATIENTS AND METHODS: During a 4 year period until December 2001, in 66 neurologically stable patients suffering a nondisabling stroke ipsilateral to a carotid artery stenosis > 50% CEA was performed after a median interval of 10 (1-28) days. The modified Rankin scale (mRS) was applied to characterize the severity of impairment of daily living activities pre- and postoperatively: Any postoperative deterioration > 24 hours on the mRS was considered as a new stroke. RESULTS: Operative mortality was 0%, and postoperative neurologic worsening > 24 hours occurred in 8/66 patients (12.1%). In 5/8 patients neurologic deterioration resolved within 5 days after surgery, only one stroke was permanent (1.5%). There was no correlation between timing of surgery or the presence of acute ipsilateral cranial CT defects with the occurrence of postoperative stroke. Stroke severity grading on admission according to the mRS, however, emerged to be a significant determinant of postoperative outcome: While 6/23 patients (26%) with an initial deficit > or = 3 on the mRS developed neurologic worsening, this was the case in only 2/43 patients (4.6%) with a deficit < or = 2 (Odds Ratio 7.2; 95% CI 1.32-39.49; two-sided p = 0.01). CONCLUSION: Our results suggest that selected patients with a minor stroke (mRS < or = 2 on admission) can safely undergo early CEA.

Aged↗

[Impaired cerebral autoregulation in asymptomatic patients with carotid artery stenosis: comparison of acetazolamide-SPECT and transcranial CO(2)-dopplersonography].

PURPOSE: The indication for operation in patients with asymptomatic high-grade carotid artery stenosis is still under debate. Since impaired cerebrovascular autoregulation is associated with an increased risk for ischaemic events, assessment of cerebral vascular reactivity might be a valuable selection criterion for surgery. The aim of our study was therefore to evaluate the incidence of impaired autoregulation in asymptomatic patients with acetazolamide-single photon emission computed tomography (ACZ-SPECT) and transcranial CO (2)-dopplersonography (CO (2)-TCD). Furthermore, both methods were compared in regard to results and clinical practicability. METHODS: In 42 patients with high-grade (> 70 %) asymptomatic carotid artery stenosis, cerebral perfusion and vascular reactivity were assessed with resting and ACZ-enhanced SPECT scans. In 31 of these patients the CO (2) reactivity of cerebral perfusion was determined by TCD and expressed as normalized autoregulation reserve (NAR). RESULTS: Cerebral perfusion was decreased in 14.3 %. In ACZ-SPECT 26 % and in CO (2)-TCD 28 % revealed an impaired vascular reactivity. Conformity of both methods was high (kappa = 0.93). TCD was superior in practicability, but only applicable in 81 % due to a missing temporal bone window for insonation. CONCLUSION: In accordance ACZ-SPECT and CO (2)-TCD could detect impaired vascular reactivity in a quarter of asymptomatic patients. Both TCD and SPECT could be of value for preoperative selection in this group of patients, whereby sonography is recommended for daily diagnostic work-up.

Acetazolamide↗

Graft patency and clinical outcome of femorodistal arterial reconstruction in diabetic and non-diabetic patients: results of a multicentre comparative analysis.

OBJECTIVE: in diabetic patients with critical limb ischaemia (CLI) an inferior success rate following infrainguinal bypass surgery is quite often suggested. The aim of this retrospective analysis was, therefore, to evaluate the graft patency and, particularly, the clinical outcome at 1 year in diabetic compared with non-diabetic patients. MATERIAL AND METHODS: two hundred and eleven patients (diabetics 94; non-diabetics 117) with femorodistal reconstruction for CLI were studied. Groups were comparable with regard to the Fontaine classification, the distribution of vascular risk factors, graft material, distal anastomosis site, and the angiographic runoff grading. RESULTS: diabetes did not adversely affect graft function. For diabetics and non-diabetics primary cumulative patency rate at 1 year was found to be 66 and 56%, respectively (p=0.10) and a virtually identical limb salvage rate of 85 and 83% was achieved (p=0.76). With regard to healing of ischaemic foot ulcers a trend against diabetics was noted with a healing rate of 81% compared to 96% in non-diabetics at 1 year (p=0.067); gangrenous foot lesions could be equally remedied in 94% and in 87% among patients with and without diabetes (p=0.44). The survival rate of diabetics, however, was significantly lower with 78% at 1 year compared with 95% in non-diabetic patients (p=0.0004). CONCLUSIONS: our preliminary results support the view that infrainguinal bypass grafting can be safely done even in diabetics. Despite increased mortality in this group, liberal indication for reconstructive vascular surgery seems to be justified by favourable patency rates and clinical outcome in selected patients.

Aged↗

[MR-angiography and duplex-ultrasonography: predictive reliability for angiographically determined internal carotid artery stenosis >/= 70-99%].

PURPOSE: A prospective study was undertaken to evaluate whether digital subtraction angiography (DSA) which is still associated with a substantial morbidity can be replaced by less invasive diagnostic modalities such as duplex scanning (DS) and magnetic resonance angiography (MR-A) for the detection of angiographically defined internal carotid artery (ICA) stenosis >/= 70 %. PATIENTS AND METHODS: A total of 47 patients with suspected severe ICA stenosis underwent examination of their carotid arteries using duplex studies, MR-A and DSA. According to the study protocol, the arteriographic diameter reduction (DR) >/= 70 % which had to be predicted by DS and MR-A was determined following the NASCET criteria. RESULTS: Stroke rate following DSA amounted to 2.1 %. In 94 carotid arteries studied by DSA 34 times a DR >/= 70 % was found. Using ROC curve for determining optimal discriminant value, duplex-derived peak systolic velocity (PSV) >/= 250 cm/s provided a sensitivity of 94.1 %, a specificity of 80 %, a positive predictive value (PPV) of 72.7 % and a negative predictive value (NPV) of 96 % to characterise an ICA stenosis >/= 70 %. Due to an inadequate PPV, PSV failed to suffice as the sole preoperative diagnostic modality even if different PSV velocity cut points were applied. On the other hand, end diastolic velocity (EDV) >/= 150 cm/s provided a PPV of 100 % thereby identifying 16/34 ICA stenoses >/= 70 % in our study. MR-A showed a sensitivity of 91.2 %, a specificity of 88.3 %, a PPV of 81.6 %, and a NPV of 94.6 % to predict an ICA stenosis >/= 70 %. CONCLUSION: In our series, both duplex-derived PSV as well as MR-A provided high sensitivity to detect surgically relevant ICA stenosis. However, to select patients for surgery inclusion of EDV proved to be important due to a high PPV and may spare conventional angiography half of patients with stenosis exceeding 70 %.

Aged↗

[Early and late results of transperitoneal thrombectomy in thrombosis of the inferior vena cava].

Acute inferior vena cava thrombosis is a rare clinical feature with unknown incidence. A clear evidence about the best treatment does not exist. Especially the indications for surgical therapy and their clinical results are published only in a few reports. So the aim of this study was to take a look to our experience and make an evaluation of the combined transcaval and transfemoral venous thrombectomy. In a retrospective study of the past 12 years 19 patients with a mean age of 28.5 years, 15 women and 4 men, showing ascension of a iliofemoral clot to the vena cava were treated by transperitoneal and transfemoral thrombectomy. The mean thrombus age was 7 days, 2 patients had bilateral iliofemoral thrombosis. Simultaneously a transfemoral thrombectomy and transcaval thrombectomy were performed after exposure of the vena cava inferior via transabdominal approach. In all cases a venous patency could be achieved, 3 times a re-thrombectomy within 1 week was necessary. One intraabdominal hematoma was revised surgically. One patient died on the first postoperative day because of a fulminant lung embolism. After a mean follow-up of 6 years 3 patients did not have any symptoms of post-thrombotic sequelae, 13 had mild and only one patient moderate post-thrombotic syndrome. The combined transperitoneal and transfemoral venous thrombectomy of the vena cava inferior represents a safe and effective treatment of the acute thrombosis of the vena cava inferior. Severe post-thrombotic sequelae especially in young women may be avoided.

Acute Disease↗

[Endovascular therapy in pelvic vein spur].

Treatment of pelvic vein spur is indicated in patients suffering from severe leg swelling and pain as well as after thrombectomy or lysis of spur-related deep vein thrombosis (DVT). In symptomatic patients without accompanying DVT, secondary patency amounted to 100% after 2 years when the spur was dilated and a self-expanding stent was implanted. In cases with successfully reopened pelvic veins after spur-induced DVT and stent application, the corresponding figure was 82%. Endovascular therapy of pelvic vein spur represents a safe and effective treatment modality. Because of its less invasive nature compared to open surgery, stent implantation has to be considered the method of first choice.

Angiography↗

Tibioperoneal arterial lesions and critical foot ischaemia: successful management by the use of short vein grafts and percutaneous transluminal angioplasty.

BACKGROUND: In a substantial number of mainly diabetic patients isolated crural arterial lesions are found to be the underlying cause for severe ischaemic foot lesions. Without revascularisation, patients with this specific occlusion pattern will inevitably face major amputation. To attain limb salvage in this setting, since the early eighties short vein grafts were used to bypass the occluded infrapopliteal arteries. More recently, percutaneous transluminal angioplasty (PTA) was also attempted to avoid limb loss in selected patients. PATIENTS AND METHODS: Since May 1986 in 125 patients 130 autologous bypass grafts from the BK-popliteal artery or the proximal tibioperoneal arteries to malleolar vessels were performed in the presence of extended crural arterial occlusions and critical foot ischaemia (rest pain 3, tissue loss 127). In another series in 89 limbs (rest pain 5, tissue loss 84) of 84 patients PTA was done to treat 168 focal stenoses of > 50% diameter reduction and 11 short occlusions in a total of 135 crural arteries. RESULTS: Using life-table analysis, primary and secondary cumulative patency rates for short vein grafts with distal graft origin were 90% and 98% at 30 days, 76% and 83% at one year and 46% and 49% at seven years, respectively. The corresponding limb salvage rates amounted to 95%, 80% and 63%. Initial complete or partial technical success after PTA of crural arteries could be obtained in 93%: The limb salvage rates achieved were 95% at 30 days, 82% at one year and 63% at six years. CONCLUSION: Our results suggest that--depending on the extent of lesions--both short vein grafts as well as PTA are successful complementary treatment modalities to avoid limb loss in predominantly diabetic patients with infrapopliteal artery disease and critical ischaemia.

Aged↗

[Intraoperative quality control in carotid surgery].

The intraoperative quality control in carotid surgery is performed by different methods: angiography, duplex-ultrasonography, transcranial Doppler ultrasonography, cw-Doppler, B-mode ultrasonography, pulsed Doppler with spectral analysis, angioscopy and flow-measurements. In Germany these measures are used only in one third of the carotid reconstructions. Especially with angiography and duplex-ultrasonography technical defects can be detected and differentiated if they were without clinical relevance like low-grade stenoses, small intima-flaps and residual plaques or needed to be reexplored. These are high-grade stenoses, acute thrombus-formations of the endarterectomised area and large intima-flaps. Abnormalities were detected in a mean of 17% of all carotid reconstructions by intraoperative control methods. In 5% severe irregularities lead to an immediate revision. Despite that there does not exist clear evidence whether the use of quality control methods reduces the perioperative neurological complication rate. It is not necessary to perform intraoperative quality control if meticulous operative technique with shunting and patch angioplasty is applied and a low perioperative complication rate is reached. For the documentation of the surgical result angiography can be recommended.

Angiography, Digital Subtraction↗

The importance of graft blood flow and peripheral outflow resistance for early patency in infrainguinal arterial reconstructions.

BACKGROUND: At present, the importance of functional parameters as determinants for graft patency is under debate. Therefore, in our institution a prospective study was undertaken to evaluate the influence of graft blood flow as well as the currently applied methods for outflow resistance measurement on early (< or = 30 days) graft outcome. PATIENT AND METHODS: 101 arterial revascularisations with infrageniculate graft insertion were entered into this study. After having verified the morphological integrity of the reconstruction, during temporary inflow occlusion total outflow resistance (TOR) was determined as a pressure/flow relationship by perfusion of the graft with saline (flow rates 25, 50, 100, 150 ml/min before and after papaverine) while simultaneously recording pressure generated at the distal anastomosis. In addition, after restoration of blood flow, flow index (FI) was calculated in an analogous way from the TBF through the graft and the respective mean distal anastomotic pressure. Graft patency at 30 days was determined by Duplex ultrasound. RESULTS: Functional parameters were found to be unable to differentiate between patent and failed reconstructions during the 30 day period: The mean TORaveraged values amounted to 722.5 (SD = 310) in patent and 735.9 (SD = 228.1) mPRU in occluded bypasses (T-value = 0.1681; n.s.). The corresponding figures were 176.8 (SD = 94.2) and 196.4 (SD = 93.6) ml/min for TBF (T-value = 0.7342; n.s.) and were 0.53 (SD = 0.34) and 0.45 (SD = 0.25) PRU for FI (T-value = 0.8905; n.s.). Using multiple logistic regression analysis functional parameters showed no influence on graft patency while graft length and the necessity for intraoperative graft modification emerged to be significant determinants of early graft outcome (R2 adjusted = 0.46; p = 0.006). CONCLUSION: The results of our study suggest that neither blood flow nor the presently used methods to assess outflow resistance are relevant prognostic factors for early (< or = 30 days) graft performance.

Adult↗

[Diabetic foot--uncontrollable infections despite successful revascularization].

We treated foot ulcerations in diabetics with limb-threatening ischemia using percutaneous balloon dilatation (44) and popliteodistal vein grafts (94). After revascularization, we observed in 12% an increase in the infection which necessitated major amputation despite open bypass or successful dilatation. A diabetic local immunodeficiency leads to cellular and humoral alterations which may cause severe tissue damage although the perfusion has been improved.

Aged↗

Superior mesenteric venous aneurysm.

The case of a 50-year-old woman with an extremely rare venous malformation of the portal venous system is reported. The patient presented with a true aneurysm of the superior mesenteric vein, which has thus far been reported in no more than eight cases worldwide. This malformation may be congenital or acquired. Secondary aneurysms are thought to be due to liver disease, portal hypertension, trauma, or inflammation. Aneurysms of the portomesenteric venous system may be asymptomatic or give rise to severe, often dramatic conditions such as crampy abdominal pain, jaundice, and upper gastrointestinal hemorrhage secondary to portal hypertension. The diagnosis is usually made by ultrasound (B-mode or color flow Doppler), CT scan, and MRI. Invasive procedures such as venous phase mesenteric arteriography or splenoportography may be helpful in confirming it. In our opinion aneurysms of the portal venous system, even if they are congenital and (still) asymptomatic, require early surgical control because the prognosis for patients with these aneurysms is unpredictable and potential complications (e.g., portal hypertension, fistula, contained perforation, or rupture) may be fatal. In the case presented the mesenteric venous aneurysm was resected and the confluent veins were reconstructed.

Aneurysm↗

[Percutaneous transluminal angioplasty (PTA) of isolated crural arterial stenoses in critical arterial occlusive disease].

PURPOSE: Retrospective analysis of the results after infrapopliteal PTA of isolated crural limb artery stenoses in patients with critical crural limb ischaemia. PATIENTS AND METHODS: Between 1989 and 1994 70 infrapopliteal dilatations of isolated crural limb artery stenoses in 44 patients (47 PTA procedures) were done with small diameter balloon catheters. 45 patients were stage IV according to Fontaine's classification, two patients were stage III. No patient had a relevant obstruction up to the popliteal artery. Follow up ranged from 1-50 months (mean 13.3 months). RESULTS: A technical success with a residual stenosis below 30% compared to the original vessel diameter was achieved in 80% of patients (n = 56). The cumulative limb-salvage rate was 76.6% after 6 to 36 months after PTA. RESULTS: In patients with chronical critical crural limb ischaemia PTA of isolated crural limb artery stenoses is an efficient therapy modality for limb-salvage. In many cases PTA is the last alternative method to amputation surgery if there is no sufficient distal vessel for a bypass.

Aged↗

[Reconstruction of isolated lower leg arteriovenous occlusions in the critical foot ischemia stage--assessment of current status].

Between May 1, 1986 and November 1, 1994 94 distal reconstructions were performed in diabetics with isolated tibioperoneal vessel occlusive disease. Mostly the below knee popliteal artery was used as inflow site and most grafts were anastomosed distally to a malleolar artery. Autologous vein was implanted throughout. Mortality at 30 days was 1.06%. Primary and secondary cumulative patency rates were 78% and 82% at 1 year, 65% and 78% at 5 years. Limb salvage rates were 76% at 1 year and 72% at 5 years. Major amputations became inevitable in 12 cases of uncontrollable foot infections despite patent grafts. This is probably due to the diabetic immunopathy. The experience we have gained suggests that distal bypasses in patients with peripheral vascular occlusive disease and critical foot ischemia are excellently suited to attain limb salvage.

Adult↗