EEG surveillance as a means of extending operability in high risk carotid endarterectomy. (1/537)

Some patients who have transient ischemic attacks are denied operation because severe occlusive lesions in other extra-cranial arteries may be inappropriately interpreted as constituting an unacceptable surgical risk, or because the lesion is so distal as to make its removal hazardous. Failure of endarterectomy is usually due to incomplete removal of the lesion or to thrombosis upon the frayed intima. Such lesions require excellent visualization and meticulous surgical technique -- not always possible with a shunt. Among 130 consecutive carotid endarterectomies performed under general anesthesia, EEG changes consistent with cerebral ischemia appeared in only nine (7%). These patients required a shunt. In 11 patients normal EEG tracings were obtained during endarterectomy despite contralateral carotid occlusion. None of these patients had a neurological deficit. Continuous EEG monitoring is a reliable method of detecting changes in cerebral perfusion, permits a more meticulous endarterectomy in high-lying lesions without a shunt, and extends operability in high risk patients. Angiographical findings may be an unreliable predictor concerning risk of endarterectomy.  (+info)

Superficial femoral eversion endarterectomy combined with a vein segment as a composite artery-vein bypass graft for infrainguinal arterial reconstruction. (2/537)

OBJECTIVE: The purpose of this study was to determine the results of composite artery-vein bypass grafting for infrainguinal arterial reconstruction. METHODS: This study was designed as a retrospective case series in two tertiary referral centers. Forty-eight of 51 patients underwent the procedure of interest for the treatment of ischemic skin lesions (n = 42), rest pain (n = 3), disabling claudication (n = 1), and infected prosthesis (n = 2). The intervention used was infrainguinal composite artery-vein bypass grafting to popliteal (n = 18) and infrapopliteal (n = 30) arteries, with an occluded segment of the superficial femoral artery prepared with eversion endarterectomy and an autogenous vein conduit harvested from greater saphenous veins (n = 43), arm veins (n = 3), and lesser saphenous veins (n = 2). The main outcome measures, primary graft patency rates, foot salvage rates, and patient survival rates, were described by means of the life-table method for a mean follow-up time of 15.5 months. RESULTS: The cumulative loss during the follow-up period was 6% and 24% at 6 and 12 months, respectively. The primary graft patency rates, the foot salvage rates, and the patient survival rates for patients with popliteal grafts were 60.0% +/- 9.07%, 75.7% +/- 9.18%, and 93.5% +/- 6.03%, respectively, at 1 month; 53.7% +/- 11.85%, 68.9% +/- 12.47%, and 85. 0% +/- 9.92% at 1 year; and 46.7% +/- 18.19%, 68.9% +/- 20.54%, and 53.1% +/- 17.15% at 5 years. For infrapopliteal grafts, the corresponding estimates were 72.4% +/- 7.06%, 72.9% +/- 6.99%, and 92.7% +/- 4.79% at 1 month; 55.6% +/- 10.70%, 55.4% +/- 10.07%, and 77.9% +/- 9.02% at 1 year; and 33.6% +/- 22.36%, 55.4% +/- 30.20%, and 20.8% +/- 9.89% at 5 years. CONCLUSION: The composite artery-vein bypass graft is a useful autogenous alternative for infrainguinal arterial reconstruction when a vein of the required quality is not available or when the procedure needs to be confined to the affected limb.  (+info)

Pulmonary embolism: one-year follow-up with echocardiography doppler and five-year survival analysis. (3/537)

BACKGROUND: The long-term prognosis for patients with pulmonary embolism (PE) is dependent on the underlying disease, degree of pulmonary hypertension (PH), and degree of right ventricular (RV) dysfunction. A precise description of the time course of pulmonary artery pressure (PAsP)/RV function is therefore of importance for the early identification of persistent PH/RV dysfunction in patients treated for acute PE. Other objectives were to identify variables associated with persistent PH/RV dysfunction and to analyze the 5-year survival rate for patients alive 1 month after inclusion. METHODS AND RESULTS: Echocardiography Doppler was performed in 78 patients with acute PE at the time of diagnosis and repeatedly during the next year. A 5-year survival analysis was made. The PAsP decreased exponentially until the beginning of a stable phase, which was 50 mm Hg at the time of diagnosis of acute PE was associated with persistent PH after 1 year. The 5-year mortality rate was associated with underlying disease. Only patients with persistent PH in the stable phase required pulmonary thromboendarterectomy within 5 years. CONCLUSIONS: An echocardiography Doppler investigation performed 6 weeks after diagnosis of acute PE can identify patients with persistent PH/RV dysfunction and may be of value in planning the follow-up and care of these patients.  (+info)

Orthostatic hypotension improved after bilateral carotid endarterectomy--case report. (4/537)

A 60-year-old male with recurrent syncopal attacks presented with orthostatic hypotension on the head-up tilt test. Angiography also showed severe stenosis of the bilateral extracranial carotid arteries. He underwent two-staged bilateral carotid endarterectomy. After the operations, the orthostatic hypotension resolved and the syncopal attacks have disappeared completely. Orthostatic hypotension in this patient was due to vasodepressor-type carotid sinus syndrome caused by compression of the carotid baroreceptors by atherosclerotic plaques.  (+info)

The role of alpha and beta platelet-derived growth factor receptor in the vascular response to injury in nonhuman primates. (5/537)

Restenosis remains a significant clinical problem associated with mechanical interventional procedures for arterial revascularization or repair, including coronary angioplasty and stenting. Studies with rodents have established that platelet-derived growth factor (PDGF), a potent chemotactic and mitogenic agent for vascular smooth muscle cells, is a key mediator of lesion formation after vascular injury. To further explore this hypothesis in a more clinically relevant model, neutralizing monoclonal antibodies (mAbs) were used to examine the effect of selective inhibition of alpha or beta PDGF receptor (PDGFR) on neointima formation in nonhuman primates. Carotid arteries were injured by surgical endarterectomy and femoral arteries by balloon catheter dilatation. Immunostaining revealed that both injuries induced cell proliferation and the upregulation of beta PDGFR but not alpha PDGFR. By 7 days after injury, beta PDGFR staining was limited to the luminal region of the media, the small areas of neointima, and the adventitia. Nearly all bromodeoxyuridine-positive cells were found in these regions as well. After 30 days, a concentric neointima that stained strongly for beta PDGFR had formed in the carotid and femoral arteries. Treatment of baboons with anti-beta PDGFR mAb 2A1E2 for 6 days after injury reduced the carotid artery and femoral artery lesion sizes by 37% (P<0.05) and 48% (P<0.005), respectively, when measured at 30 days. Under the same conditions, treatment with anti-alpha PDGFR mAb 2H7C5 had no effect. These findings suggest that PDGF mediates neointima formation through the beta PDGFR, and that antagonism of this pathway may be a promising therapeutic strategy for reducing clinical restenosis.  (+info)

Glucocorticoid resistance caused by reduced expression of the glucocorticoid receptor in cells from human vascular lesions. (6/537)

Mechanisms that control the balance between cell proliferation and death are important in the development of vascular lesions. Rat primary smooth muscle cells were 80% inhibited by low microgram doses of hydrocortisone (HC) and 50% inhibited by nanogram concentrations of transforming growth factor-beta1 (TGF-beta1), although some lines acquired resistance in late passage. However, comparable doses of HC, or TGF-beta1, failed to inhibit most human lesion-derived cell (LDC) lines. In sensitive LDC, HC (10 microg/mL) inhibited proliferation by up to 50%, with obvious apoptosis in some lines, and TGF-beta1 inhibited proliferation by more than 90%. Collagen production, as measured by [3H]proline incorporation or RIA for type III pro-collagen, was either unaffected or increased in the LDCs by HC. These divergent responses between LDC lines were partially explained by the absence of the glucocorticoid receptor (GR) and heat shock protein 90 mRNA in 10 of 12 LDC lines, but the presence of the mineralocorticoid receptor and 11beta-hydroxysteroid dehydrogenase type II. Western blot analysis confirmed the absence of the GR protein in cells lacking GR mRNA. Immunohistochemistry of human carotid lesions showed high levels of GR in the tunica media, but large areas lacking GR in the fibrous lesion. Considering the absence of the GR in most lines, the effects of HC may be elicited through the mineralocorticoid receptor. Functional resistance to the antiproliferative and antifibrotic effects of HC may contribute to excessive wound repair in atherosclerosis and restenosis.  (+info)

Prospective randomized trial of bilateral carotid endarterectomies: primary closure versus patching. (7/537)

BACKGROUND AND PURPOSE: Although several studies have compared the results of carotid endarterectomy (CEA) with primary closure (PC) versus patch closure, none have compared the outcome of bilateral CEAs with patch versus PC performed on the same patient. This prospective randomized study compares the clinical outcome and incidence of recurrent stenosis (>/=80%) for CEA with PC versus patch closure in patients with bilateral CEAs. METHODS: This study includes 74 patients with bilateral CEAs with PC on one side and patching on the other. Patients were randomized to sequential operative treatment of either patching/PC or PC/patching. Postoperative duplex ultrasounds and clinical follow-up were done at 1, 6, and 12 months and every year thereafter. A Kaplan-Meier analysis was used to estimate the risk of significant restenosis (>/=80%). RESULTS: Demographic characteristics and the mean operative diameter of the internal carotid artery were similar for both PC and patching. The mean follow-up was 29 months (range, 6 to 65 months). The incidence of ipsilateral stroke was 4% for PC versus 0% for patching. PC had a significantly higher incidence of neurological complications (transient ischemic attacks and stroke combined) than patching (12% versus 1%; P=0.02). Operative mortality was 0%. PC had a higher incidence of recurrent stenosis (22% versus 1%; P<0.003) and total internal carotid artery occlusion (8% versus 0%; P=0.04) than patching. Restenoses necessitating a repeated CEA were also higher for PC (14%) than for patching (1%; P=0.01). The Kaplan-Meier analysis showed that patching had a significantly better cumulative patency rate than PC (P<0.01). This analysis also showed that freedom from recurrent stenosis at 24 months was 75% for PC and 98% for patching. CONCLUSIONS: Patch closure is less likely than PC to cause ipsilateral stroke, transient ischemic attacks, and recurrent carotid stenosis. The higher rate of unilateral recurrent stenosis may suggest that local factors play a more significant role than systemic factors in the etiology of recurrent carotid stenosis.  (+info)

Semi-closed femoropopliteal thromboendarterectomy: a prospective study. (8/537)

OBJECTIVE: to study the primary patency rates of angioscopically controlled thromboendarterectomies of the superficial femoral artery. DESIGN: prospective open study. METHODS: between 1990 and 1995, femoropopliteal thromboendarterectomies were performed in 63 patients (41 male, 22 female). Postoperative follow up was performed at 3- to 6-month intervals using non-invasive pressure measurements plus IVDSA at 1 year. RESULTS: eight patients were not evaluable, leaving 55 patients eligible for follow-up analysis. Postoperative complications (arteriovenous fistulas, false aneurysms) were observed in 5.4% of patients. Immediate perioperative occlusions occurred in 7.3%, early occlusions in 21.8% and late occlusions in 16.4% of all cases. The mean follow-up was approximately 57 months. The mean primary patency rate at 5 years was 44.5% (28 patients with the superficial femoral artery still open). Six patients died during the follow-up period. CONCLUSIONS: in contrast to the very positive reports found in recent literature, this prospective study shows a lower five-year patency rate for semi-closed femoropopliteal thromboendarterectomy than for bypass grafting. Thromboendarterectomy cannot be considered as a standard procedure in revascularisation of the femoropopliteal region.  (+info)