Selection of patients for cardiac evaluation before peripheral vascular operations.

Purpose: This study evaluated the value of preoperative cardiac screening with dipyridamole thallium scintigraphy and radionuclide ventriculography in vascular surgery patients.

Methods: From July 1, 1989, to Dec. 31, 1991, we routinely (irrespective of the patient's cardiac history or symptomatology) performed dipyridamole thallium scintigraphy (DTS) and radionuclide ventriculography (RVG) in 394 patients being considered for an elective vascular operation.

Mechanical regulation of cardiac myocyte protein turnover and myofibrillar structure.

Mechanical forces play an essential role in regulating the synthesis and assembly of contractile proteins into the sarcomeres of cardiac myocytes. To examine if physical forces might also regulate the turnover of contractile proteins at a posttranslational site of control, beating and nonbeating neonatal cardiac myocytes (NCM) were subjected to a 5% static stretch. The L-type calcium channel blocker nifedipine (12 microM) was used to inhibit contraction.

Lateral approach to the popliteal and crural vessels for limb salvage.

Twenty-one patients underwent 23 bypasses for limb salvage via a lateral approach with subcutaneous graft tunneling. The reasons for utilizing a lateral approach were medial infection (10 bypasses), scarring from previous surgery (six), limited vein length available (three), prior local radiotherapy (two) and 'high risk' groin (two). The target artery was the anterior tibial in 16 cases, the peroneal in three, the above-knee popliteal in three and the dorsalis pedis in one.

The aortic polytetrafluoroethylene graft: further experience.

Objectives: We analysed our results with the use of aortic polytetrafluoroethylene PTFE grafts over the last 7.5 years. A historical comparison was also made between the results with non-stretch PTFE (NS-PTFE) (1987-91) and stretch PTFE (S-PTFE) grafts (1991-94).

Fecal impaction as a cause of acute lower limb ischemia.

Acute lower extremity ischemia secondary to fecal impaction has not been previously reported. Herein, we report the case of an elderly man who was referred to our medical center with an acutely ischemic right lower extremity and a possible abdominal aortic aneurysm. The suspicious abdominal mass noted by his local physician was found to be a large fecal impaction of the rectosigmoid which, by direct pressure, was compressing and occluding the right common iliac artery.

Late results of a prospective study of direct intra-arterial urokinase infusion for peripheral arterial and bypass graft occlusions.

The outcome of 72 direct intra-arterial urokinase infusions was studied prospectively. Thirty four were performed for native arterial occlusion and 38 for bypass graft occlusion; the immediate success rates were 67.5 and 84% respectively.

A comparative evaluation of externally supported polytetrafluoroethylene axillobifemoral and axillounifemoral bypass grafts.

Purpose: We analyzed a current 78-month experience with externally supported (ringed) polytetrafluoroethylene (PTFE) axillobifemoral (AxBF) and axillounifemoral (AxUF) bypass grafts to address the controversy about whether the addition of a femorofemoral limb to an axillofemoral bypass graft improves the patency results.

Methods: Between January 1988 and June 1994, 36 AxBF and 22 AxUF externally supported PTFE ringed bypass grafts were performed at our institution. The age of the patients in the AxBF group was 67 +/- 11 years and 69 +/- 11 years in the AxUF group.

Should all in situ saphenous vein bypasses undergo permanent duplex surveillance?

Objective: To evaluate the need for color duplex surveillance (CDS) for pure in situ bypasses beyond 6 months.

Design: We reviewed our in situ surveillance data from August 1987 to April 1994. Lower-extremity revascularization was performed using 245 pure in situ greater saphenous vein bypasses in 219 patients.

Mechanical regulation of cardiac myofibrillar structure.

The excitation-contraction coupling cycle (ECC) consists of a complex cascade of electrochemical and mechanical events; however, the relative contributions of these different processes in the regulation of cardiac myofibrillar structure are not well understood. There is extensive evidence to suggest that the mechanical aspects of the ECC play a crucial role in controlling the availability of contractile proteins for myofibrillar assembly. To examine if these physical forces might also serve to stabilize the structure of preexisting myofibrils, beating and nonbeating cultures of neonatal cardiac myocytes (NCM) were subjected to a 5% static stretch.

Comparative efficacy and complications of vena caval filters.

Purpose: A variety of vena caval filters (VCFs) are available for usage. The choice of filter type depends on physician preference and certain patient variables. An evaluation of the different VCFs used in our institution was done to compare their efficacy and complication rates.

Effect of an endovascular stent on healing of an end-to-end polytetrafluoroethylene-artery anastomosis in a canine model.

A canine model of end-to-end anastomosis between the iliac arteries and polytetrafluoroethylene grafts was developed; a self-expanding Wallstent was placed across one anastomosis. The opposite limb acted as a control. Animals were killed at 4 or 12 weeks.

The effect of an intraluminal stent on neointimal hyperplasia at an end-to-side polytetrafluoroethylene graft arterial anastomosis.

Background: Anastomotic neointimal hyperplasia plays a significant role in the late failure of infrainguinal prosthetic arterial bypass grafts. Previous work from our laboratory revealed that placing a stent across an end-to-end arterio-arterial anastomosis resulted in an increase in the luminal area as well as in the intimal thickness (IT) at the anastomotic level. This study was designed to evaluate the effects on neointimal hyperplasia when a stent is placed across an end-to-side polytetrafluoroethylene (PTFE) graft arterial anastomosis.

The management of the infected aortic prosthesis: a current decade of experience.

Purpose: Newer approaches to the patient with an infected aortic graft are available. We reviewed a recent 10-year experience with a more traditional approach to evaluate its outcome in the 1990s.

Methods: From January 1983 to January 1993, 27 patients with an aortic graft infection were treated at our institution.

Effect of HLA matching on organ distribution among whites and African-Americans.

A total of 159 patients received renal cadaveric grafts under 2 different allocation systems. System 1, a local variance (i.e.

The impact of color duplex surveillance on the outcome of lower limb bypass with segments of arm veins.

Purpose: To evaluate prospectively 42 lower extremity arm vein bypasses with use of color duplex surveillance (CDS).

Methods: Twenty-seven bypasses (64%) were to tibial arteries, 12 (29%) were to popliteal arteries, and three (7%) were to superficial femoral arteries. Twelve bypasses were composed of a single arm vein segment, and 30 were composite vein bypasses.

Back-table renal allograft angioscopy and thrombolysis.

Poor back-table perfusion of a renal allograft may occur as a result of intravascular thrombosis of the renal artery branches. We herein report such a case where back-table angioscopy was performed to confirm the diagnosis, followed by successful thrombolysis using urokinase under hypothermic conditions.

Is there a conduit of preference for a bypass between the carotid and subclavian arteries?

The conduit of choice for a bypass between the carotid and subclavian arteries remains controversial. We retrospectively evaluated 32 patients who underwent bypass between the carotid and subclavian arteries. Perioperative mortality was limited to a single patient who sustained a myocardial infarction.

Is the use of intraoperative post-reconstruction angiography following in situ saphenous vein bypass redundant?

The value of post-reconstruction intraoperative angiography after in situ saphenous vein bypass has not been clearly defined. A retrospective review of intraoperative completion angiography using a standard proximal bypass injection technique without inflow occlusion was performed on 298 in situ saphenous vein bypasses constructed over a 72-month interval to treat critically ischemic limbs. Abnormal operative angiograms were found on retrospective review in 55 cases (18%).

Contractile activity modulates actin synthesis and turnover in cultured neonatal rat heart cells.

In this study, the role that active tension development plays in the formation and maintenance of cardiac myocyte myofibrillar structure and cellular shape was investigated. By use of the calcium channel blocker verapamil, spontaneous contractile activity of neonatal rat heart myocytes was inhibited for 24 to 96 hours. Confocal microscopy of rhodamine phalloidin-stained cells revealed that, within 24 hours of contractile arrest, actin filaments of myofibrils were no longer aligned with one another at their I bands and Z lines.

Aortic aneurysm rupture into a retroaortic left renal vein.

We report the case of a patient who was transferred to our facility after a CT scan obtained at a local hospital revealed a leaking abdominal aortic aneurysm. Review of the scan showed an aorto-left renal vein fistula. Knowing this fistula was present made the operative repair of the aneurysm and control of the fistula much more straightforward than might otherwise have been the case.

Technical aspects and results of the open in situ saphenous vein bypass technique.

We reviewed 284 consecutive in situ saphenous vein bypass procedures performed for limb salvage over a 66 month period. All procedures were performed using an open technique with a modified Mills retrograde valvulotome using an incision exposing the whole vein. Ninety-eight percent were to the infrageniculate level (18% below knee popliteal and 80% crural).