Surgical and endovascular intervention for infrainguinal vein graft stenosis.

PURPOSE: The purpose of this study was to evaluate the stenosis-free patency of open repair (vein-patch angioplasty, interposition, jump grafting) and percutaneous transluminal balloon angioplasty (PTA) of 144 vein graft stenoses that were detected during duplex scan surveillance after infrainguinal vein bypass grafting. METHODS: Patients who underwent revision of an infrainguinal vein bypass graft were analyzed for type of vein conduit, vascular laboratory findings leading to revision, repair techniques, assisted graft patency rate, procedure mortality rate, and restenosis of the repair site. RESULTS: The time of postoperative revision ranged from 1 day to 133 months (mean, 13 months). One hundred eighteen primary and 26 recurrent stenoses (peak systolic velocity, >300 cm/s) in 52 tibial and 35 popliteal vein bypass grafts were identified by means of duplex scanning. The repairs consisted of 77 open procedures (vein-patch angioplasty, 28; vein interposition, 33; jump graft, 9; primary repair, 3) and 67 PTAs. No patient died as a result of intervention. Cumulative assisted graft patency rate (life-table analysis) was 91% at 1 year and 80% at 3 years. At 2 years, cumulative assisted graft patency rate was comparable for saphenous vein grafts (reversed, 94%; in situ, 88%; nonreversed, 63%) and alternative vein grafts (89%). Stenosis-free patency rate at 2 years was identical (P =.55) for surgical intervention (63%) and endovascular intervention (63%) but varied with type of surgical revision (P =.04) and time of intervention (<4 months, 45%; >4 months, 71%; P =.006). The use of duplex scan-monitored PTA to treat focal stenoses (<2 cm) and late-appearing stenoses (>3 months) was associated with a stenosis-free patency rate that was 89% at 1 year. After intervention, the alternative vein bypass grafts necessitated twice the reinterventions per month of graft survival (P =.01). Bypass graft to the popliteal versus infrageniculate arteries, site of graft stenosis (vein conduit, anastomotic region), and repair of a primary versus a recurrent stenosis did not influence the outcome after intervention. CONCLUSION: The revision of duplex scan-detected vein graft stenosis with surgical or endovascular techniques was associated with an excellent patency rate, including when intervention on alternative vein conduits or treatment of restenosis was necessary. When PTA was selected on the basis of clinical and duplex scan selection criteria, the endovascular treatment of focal vein graft stenosis was effective, durable, and comparable with the surgical revision of more extensive lesions.

Differential effects on portal and effective hepatic blood flow. A comparison between transjugular intrahepatic portasystemic shunt and small-diameter H-graft portacaval shunt.

OBJECTIVE: This study was undertaken to determine the effects of transjugular intrahepatic portasystemic shunt (TIPS) and small-diameter prosthetic H-graft portacaval shunt (HGPCS) on portal and effective hepatic blood flow. SUMMARY BACKGROUND DATA: Mortality after TIPS is higher than after HGPCS for bleeding varices. This higher mortality is because of hepatic failure, possibly a result of excessive diminution of hepatic blood flow. METHODS: Forty patients randomized prospectively to undergo TIPS or HGPCS had effective hepatic blood flow determined 1 day preshunt and 5 days postshunt using low-dose galactose clearance. Portal blood flow was determined using color-flow Doppler ultrasound. RESULTS: Treatment groups were similar in age, gender, and Child's class. Each procedure significantly reduced portal pressures and portasystemic pressure gradients. Portal flow after TIPS increased (21 mL/second +/- 11.9 to 31 mL/second +/- 16.9, p < 0.05), whereas it remained unchanged after HGPCS (26 mL/second +/- 27.7 to 14 mL/second +/- 41.1, p = n.s.). Effective hepatic blood flow was diminished significantly after TIPS (1684 mL/minute +/- 2161 to 676 mL/minute +/- 451, p < 0.05) and was unaffected by HGPCS (1901 mL/ minute +/- 1818 to 1662 mL/minute +/- 1035, p = n.s.). CONCLUSIONS: Both TIPS and HGPCS achieved significant reductions in portal vein pressure gradients. Portal flow increased after TIPS, although most portal flow was diverted through the shunt. Effective hepatic flow is reduced significantly after TIPS but well preserved after HGPCS. Hepatic decompensation and mortality after TIPS may be because, at least in part, of reductions in nutrient hepatic flow.

A prospective trial of transjugular intrahepatic portasystemic stent shunts versus small-diameter prosthetic H-graft portacaval shunts in the treatment of bleeding varices.

OBJECTIVE: The authors compare transjugular intrahepatic portasystemic stent shunts (TIPS) to small-diameter prosthetic H-graft portacaval shunts (HGPCS). SUMMARY BACKGROUND DATA: Transjugular intrahepatic portasystemic stent shunts have been embraced as a first-line therapy in the treatment of bleeding varices due to portal hypertension, although they have not been compared to operatively placed shunts in a prospective trial. METHODS: In 1993, the authors began a prospective, randomized trial to compare TIPS with HGPCSs. All patients had bleeding varices and had failed nonoperative management. Shunting was undertaken as definitive therapy in all. Failure of shunting was defined as an inability to accomplish shunting despite repeated attempts, unexpected liver failure leading to transplantation, irreversible shunt occlusion, major variceal rehemorrhage, or death. Mortality and failure rates were analyzed at 30 days (early) and after 30 days (late) using Fischer's exact test. RESULTS: There were 35 patients in each group, with no difference in age, gender, Child's class, etiology of cirrhosis, urgency of shunting, or incidence of ascites or encephalopathy between groups. In two patients, TIPS could not be placed despite repeated attempts. Transjugular intrahepatic portasystemic stent shunts reduced portal pressures from 32 +/- 7.5 mmHg (standard deviation) to 25 +/- 7.5 mmHg (p < 0.01), whereas HGPCS reduced them from 30 +/- 4.6 mmHg to 19 +/- 5.3 mmHg (p < 0.01; paired Student's test). Irreversible occlusion occurred in three patients after placement of TIPS. Total failure rate after TIPS placement was 57%; after HGPCS placement, it was 26% (p < 0.02). CONCLUSIONS: Both TIPS and HGPCS reduced portal pressure. Placement of TIPS resulted in more deaths, more rebleeding, and more than twice the treatment failures. Mortality and failure rates promote the application of HGPCS over TIPS.

Bronchial carcinoid tumors: assessment with CT of location and intratumoral calcification in 31 patients.

Bronchial carcinoid tumors (BCT) have long been regarded as predominantly central and rarely calcified. The authors retrospectively reviewed computed tomographic (CT) findings in 31 patients (thin-section CT studies in 18) who were seen at their institution with the histopathologic diagnosis of BCT (27 typical, four atypical) during the years 1978-1989. Eighteen BCT (58%) were central and 13 (42%) peripheral, with peripheral defined as located more than 2 cm distal to the origin of the appropriate segmental bronchus. CT scans revealed varied patterns of calcification in seven (39%) of the 18 central BCT and in one (8%) of the 13 peripheral BCT (P less than .1); overall, CT scans revealed calcification in eight (26%) of the BCT. The eight calcified tumors were each of the typical histopathologic type. Peripheral BCT (42%) were nearly as common as central BCT (58%), and CT detection of calcification in BCT was not uncommon (39% of central lesions; 26%, overall).