Right atrial bypass grafting for central venous obstruction associated with dialysis access: another treatment option. (1/149)

PURPOSE: Central venous obstruction is a common problem in patients with chronic renal failure who undergo maintenance hemodialysis. We studied the use of right atrial bypass grafting in nine cases of central venous obstruction associated with upper extremity venous hypertension. To better understand the options for managing this condition, we discuss the roles of surgery and percutaneous transluminal angioplasty with stent placement. METHODS: All patients had previously undergone placement of bilateral temporary subclavian vein dialysis catheters. Severe arm swelling, graft thrombosis, or graft malfunction developed because of central venous stenosis or obstruction in the absence of alternative access sites. A large-diameter (10 to 16 mm) externally reinforced polytetrafluoroethylene (GoreTex) graft was used to bypass the obstructed vein and was anastomosed to the right atrial appendage. This technique was used to bypass six lesions in the subclavian vein, two lesions at the innominate vein/superior vena caval junction, and one lesion in the distal axillary vein. RESULTS: All patients except one had significant resolution of symptoms without operative mortality. Bypass grafts remained patent, allowing the arteriovenous grafts to provide functional access for 1.5 to 52 months (mean, 15.4 months) after surgery. CONCLUSION: Because no mortality directly resulted from the procedure and the morbidity rate was acceptable, this bypass grafting technique was adequate in maintaining the dialysis access needed by these patients. Because of the magnitude of the procedure, we recommend it only for the occasional patient in whom all other access sites are exhausted and in whom percutaneous dilation and/or stenting has failed.  (+info)

Volume flow measurement in hemodialysis shunts using time-domain correlation. (2/149)

Volume flow was measured in 58 hemodialysis shunts (32 grafts and 26 radial fistulas) using the color velocity imaging-quantification method. This method is based on time-domain correlation for velocity calculation and integration of time-varying velocity profiles generated by M-mode sampling. Measurements were made in the brachial artery to estimate radial fistula flow or directly in the grafts. Intraoperator reproducibility was 14.9% for fistulas and 11.6% for grafts. Flow rate was significantly lower in abnormal shunts associated with a functional disorder or a morphologic complication (808 ml/min +/- 484) than in shunts associated with no abnormalities (1401 ml/min +/- 562). Receiver operating characteristic curves showed that a flow rate of 900 ml/min for fistulas and 1300 ml/min for grafts provided 81% and 79% sensitivity and 79% and 67% specificity, respectively. A functional disorder or a morphologic complication was associated with all fistulas and grafts in which flow rates were lower than 500 ml/min and 800 ml/min, respectively.  (+info)

The snuffbox arteriovenous fistula for vascular access. (3/149)

OBJECTIVES: to determine the applicability, patency rates and factors influencing patency of snuffbox arteriovenous fistulae for haemodialysis access. DESIGN: retrospective non-randomised study. MATERIALS AND METHODS: patency was determined by reference to an ongoing database and dialysis records of 645 vascular access procedures between 1985 and 1997, including 210 snuffbox fistulae in 201 patients. RESULTS: snuffbox fistulae comprised 189/376 (50%) primary procedures. Records of 208 snuffbox fistulae were available for patency analysis by the life-table method. Twenty-two (11%) thrombosed within 24 hours of operation. After six weeks 80% were used for dialysis. Cumulative patency was 65% at 1 year and 45% at 5 years. After thrombosis of snuffbox fistulae, ipsilateral wrist fistulae could be constructed in 45%. Fistula patency was significantly better in men than women (p<0.001) and for left- than right-sided fistulae (p<0.001). Diabetes, age >70 years, and the prior commencement of haemodialysis did not significantly affect fistula survival. CONCLUSIONS: the snuffbox AV fistula gives a long segment of arterialised vein for needling and preserves proximal vessels. It is feasible in 50% of patients requiring primary access and has good long-term patency, especially in men. A more proximal fistula may be preferable in women with smaller vessels.  (+info)

Minimally invasive thymoma with extensive intravascular growth. (4/149)

A 70-year-old male with grossly non-invasive thymic tumor associated with myasthenia gravis was subjected to thymothymectomy. Microscopic examination showed extensive intravascular tumor extensions into veins of thymic tissue and surrounding muscles and a minute direct invasion of the thymic tissue. Histologically, the tumor showed mixed-type thymoma with polygonal epithelial cells. These pathological findings indicated that the tumor cells extended mainly into vessels beyond the tumor capsule via tumor drainage veins rather than invading neighboring structures. After chemotherapy and mediastinal irradiation, the patient is now in complete remission of myasthenia gravis and is recurrence-free 15 months after surgery.  (+info)

Occlusion of azygos vein via direct percutaneous puncture of innominate vein following cavopulmonary anastomosis. (5/149)

A 2-year-10-month-old boy was diagnosed with a complex congenital heart disease: right atrial isomerism, left superior vena cava (LSVC), complete atrioventricular septal defect, secundum type atrial septal defect, transposition of the great arteries with pulmonary atresia, patent ductus arteriosus, absence of a right superior vena cava (RSVC), and dextrocardia. He had received a left Blalock-Taussig (BT) shunt at the age of 3 months and a left bidirectional Glenn shunt one year after BT shunt. Progressive cyanosis was noted after the second operation and cardiac catheterization showed a functional Glenn shunt with an engorged azygos vein, which was inadvertently skipped for ligation. Because of the absence of RSVC, transcatheter occlusion of the azygos vein was performed successfully via direct puncture of the innominate vein.  (+info)

Crushed stents in benign left brachiocephalic vein stenoses. (6/149)

Two hemodialysis patients presenting with left venous arm congestion due to benign catheter-induced stenosis of the left brachiocephalic vein were treated by angioplasty and stent placement. External compression of the stents was responsible for rapid recurrence of the symptoms. No osseous or vascular malformation could be identified. Mechanical constraints induced by respiratory chest wall motion and aortic arch flow-related pulsation are proposed to explain this observation. This potential hazard should be considered when stent placement into the left brachiocephalic vein is advocated.  (+info)

Stent placement for treatment of central and peripheral venous obstruction: a long-term multi-institutional experience. (7/149)

PURPOSE: The clinical success and patency of central and peripheral venous stents in patients with symptomatic venous obstruction (SVO) were assessed. METHODS: The records of patients with SVO treated with venous stents from 1992 to 1999 were reviewed. Demographic and procedural variables were analyzed to determine their effect on clinical success, primary patency, and secondary patency. Patency was determined by means of a follow-up duplex scan or venogram. RESULTS: Forty central venous (CV) and 14 peripheral venous (PV) obstructions were treated in 49 patients. Sixty-five stents were placed (50 CV and 15 PV), 54 in previously unstented lesions and 11 in previously stented lesions. Causes of CV lesions included catheter placement (82%), tumor compression (6%), arteriovenous fistula (AVF) and no prior catheter (2%), and other (10%). All PV lesions resulted from complications of dialysis. Indications for CV stents included limb edema (46%), AVF malfunction (30%), both limb edema and AVF malfunction (14%), and other (10%). PV stent indications were AVF malfunction (86%) and limb edema (14%). Thirteen CV stents indicated to treat tumor compression (three cases), May-Thurner syndrome (one case), deep venous thrombosis (three cases), superior vena cava syndrome (one case), and lower-extremity catheter-related lesions (five cases) were excluded from the analysis of clinical outcome. Fifty-two stents (37 CV and 15 PV) were included in the analysis of clinical outcome. All CV lesions included in the analysis were complications of prolonged catheterization. Eighty-nine percent of patients had end-stage renal disease and an AVF. Complications developed in 26% of patients with PV stents and in no patients with CV stents (P <.002). The mean follow-up period was 16 months. Sixty-two percent of patients required a reintervention for recurrent SVO. Only 32% of the interventions resulted in sustained symptomatic improvement. For CV stents, the primary patency rate was 85%, 27%, and 9% at 3, 12, and 24 months, respectively; the secondary patency rate was 91%, 71%, and 39% at 3, 12, and 24 months, respectively; and the clinical success rate was 94%, 94%, and 79%, at 3, 12, and 24 months, respectively. For PV stents, the primary patency rate was 73%, 17% and 17% at 3, 12, and 24 months, respectively; the secondary patency rate was 80%, 56%, and 35% at 3, 12, and 24 months, respectively; and the clinical success rate was 92%, 75%, and 42% at 3, 12 and 24 months, respectively. CONCLUSION: Stents provide a temporary benefit in most patients with central or peripheral upper-extremity SVO. Regular follow-up and reinterventions are required to maintain patency and achieve long-term clinical success. Stents used for CV lesions have higher clinical success rates than stents used for PV lesions. Patients with a reasonable life expectancy or who are unable to return for subsequent procedures should be considered for undergoing alternative therapy.  (+info)

Arteriovenous fistulae complicating cardiac pacemaker lead extraction: recognition, evaluation, and management. (8/149)

Transvenous pacemaker lead extraction has become a commonly performed procedure that is associated with a small but significant risk. We report two cases where lead extraction was complicated by arteriovenous fistulae between branches of the aortic arch and the left brachiocephalic vein. Presenting signs and symptoms included severe chest or back pain, persistent or copious bleeding from the venous puncture site, unexplained hypotension or anemia, superior vena cava syndrome, and signs of central venous hypertension or acute heart failure. One patient whose injury was not recognized immediately and who did not undergo repair died rapidly, whereas the other patient who was diagnosed quickly underwent successful repair. Immediate diagnosis with arteriography and rapid intervention with surgery or percutaneous techniques are indicated and may prevent mortality.  (+info)

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