Percutaneous transluminal dilation in renal transplant arterial stenosis.

Twelve hypertensive patients underwent percutaneous transluminal dilation (PTD) for relief of arterial stenosis complicating renal allotransplantation. Two patients underwent repeat PTD for recurrent stenosis and hypertension. Six patients had end to end anastomosis of the donor renal artery to the recipient hypogastric artery; four of six PTDs were successful. Six patients had end to side anastomosis of the donor renal artery to the recipient external iliac artery; seven of eight PTDs, including one of two repeat PTDs, were successful. Prior to PTD, all patients were using several antihypertensive medications. Following successful PTD, the mean blood pressure dropped from 184 +/- 15/118 +/- 9 to 133 +/- 13/89 +/- 11 mm Hg (P < 0.001) and remained at that level for up to 15 months (average followup 9 months) with decreased or no antihypertensive medications. Since surgical correction of arterial stenosis occurring after renal transplantation is difficult and may endanger the graft, PTD should be the first interventional therapy.

Preoperative saphenous venography in arterial reconstructive surgery of the lower extremity.

Preoperative saphenous venography was performed in 100 extremities in 60 patients to evaluate the saphenous vein for use as an arterial bypass graft. In 18 of the patients (30%), venography demonstrated vein abnormality, disease, or small size, which significantly influenced the management of the patient or the conduct of the operation. Good correlation was observed between venographically determined saphenous vein anatomy and diameter and those observed at operation in 52 patients. The average diameter of the saphenous veins on preoperative venograms was 3.4 mm (range, 1.0 to 6.0 mm). These veins dilated to an average diameter 73 +/- 5% greater than that observed venographically, so that the average diameter of harvested, dilated saphenous veins was 5.5 mm (range, 3.0 to 10.0 mm). All veins measuring 2.0 mm or more on the venograms dilated to 4.0 mm or more at operation and were suitable for femoropopliteal or small vessel bypass grafts. Four saphenous veins measuring 1.0 mm or more on the venograms dilated to 3.0 mm or more at operation and were suitable for small vessel bypasses. Thus preoperative saphenous venography can be of value in lower extremity arterial reconstructions. The procedure allows detection of anomalies and disease processes that would prevent the use of one or both saphenous veins as arterial bypass grafts and identifies the best available venous segment thereby obviating unnecessary incisions and minimizing operating time.

Clinical experience with modified human umbilical cord vein for arterial bypass.

Umbilical veins were removed from human cords, tanned with gluteraldehyde, and surrounded by a polyester fiber mesh. Arterial bypasses were performed with this material in eight persons with threatened limb loss and for whom no other graft material was available. The distal anastomoses were to the small vessels of the leg or to the popliteal artery below the knee. Limb salvage and function were obtained in five patients. Three of these also required early thrombectomy to obtain success. This complication may be related to the presence of gluteraldehyde oligomers and polymers of free aldehyde groups. Morphologic evaluation of the graft suggests that human umbilical cords are a potentially valuable source for vascular substitutes.

Celiac artery aneurysmectomy: case report with review of the literature.

A case of celiac trunk aneurysm treated by excision and direct reanastomosis with restoration of arterial continuity, and a description of a new technique for selective visualization of the celiac artery are reported. A review of the literature with tabulation of all surgically treated cases is included. Significance of hepatic artery flow restoration is emphasized.

Patient selection and improved technical factors in small-vessel bypass procedures of the lower extremity.

Thirty-two small-vessel bypasses were constructed as limb-salvage procedures. The one month patency rate was 72 percent and the one year cumulative patency rate was 55 percent. Preoperative, intraoperative, and postoperative angiography was performed in most cases and the results correlated with the ultimate fate of the graft. Preoperative angiography is critical in determining the location of a suitable small vessel, including the peroneal artery, and the quality of the runoff. Intraoperative angiography is required to delineate correctable intraoperative defects usually appearing at the distal anastomotic area. Additionally, failure to demonstrate runoff or a pedal arch can help support a decision not to re-explore a graft should early closure occur. Postoperative angiography is essential to validate clinical success with graft patency and function. It also serves to discover potential graft defects that might otherwise lead to closure and potential limb loss. Selected cases of failed small-vessel bypass grafts may be salvaged by thrombectomy with or without graft revision. Small-vessel bypass is generally contraindicated if there is extensive tissue necrosis and infection extending into the proximal foot. In cases where the necrotizing infection is localized, particularly to the forefoot, then open drainage, debridement, or amputation should be performed together with small-vessel bypass. Finally, the risks indigenous to small-vessel bypass procedures demand optimal patient selection and exquisite operative technique.

Limb salvage in octogenarians and nonagenarians.

Although advanced age has often been a relative contraindication to attempts at limb salvage, we have not regarded it as an important deterrent to arterial reconstruction. Our 6-year experience with 168 consecutive patients over 80 years of age who underwent arterial reconstruction or percutaneous transluminal angioplasty represented 18% of all patients treated with limb-threatening ischemia during this period. The average age was 84 years, with 14 patients over 90 years of age. Sixty-eight patients were men (41%) and 100 were women (59%). Indications for treatment in 189 limbs were restricted to limb salvage. One hundred eighty-two operative procedures were performed consisting of 84 femoropopliteal, 72 femorotibial, 12 axillofemoral, 11 femorofemoral, two axillopopliteal and one iliofemoral bypass. Percutaneous transluminal angioplasty was performed in 12 iliac and 14 femoral or popliteal arteries as an alternative (seven) or adjunct (19) to vascular reconstruction. The 30-day procedural mortality rate was 6%. The cumulative life table survival rate of all patients who underwent an attempt at limb salvage was 78% at 1 year, 65% at 2 years, and 54% at 3 years. Cumulative life table limb salvage rates were 84% at 1 year, 74% at 2 years, and 71% at 3 years. Overall graft patency for 182 arterial reconstructive operations was 80% at 1 year and 62% at 3 years. Of patients in whom limb salvage was attempted, 65% lived more than 1 year and 51% more than 2 years with a functional limb. Of patients who died within 5 years of treatment, 76% did so with their previously threatened limb intact. These data support an aggressive approach to arterial reconstruction in elderly patients and indicate that advanced age alone should not be considered a contraindication to attempts at limb salvage.

Comparison of axillounifemoral and axillobifemoral bypass operations.

Routine use of axillobifemoral (ABF) bypass has been advocated because this operation is thought to achieve better patency than the axillounifemoral (AUF) procedure. In 5 years we performed 34 AUF and 22 ABF bypass operations for limb salvage in high-risk patients using 6 mm polytetrafluoroethylene grafts. Five-year cumulative life table patency rates for AUF bypasses were 71% with reoperation (secondary patency) and 44% without reoperation (primary patency). These values were not significantly different (p greater than 0.5) from those for ABF bypasses (77% and 50%, respectively). Five-year limb salvage results (AUF 73%; ABF 89%) were also not significantly different (p greater than 0.1). Correlation of arterial outflow characteristics with graft patency revealed that 78% of the patients who never had graft occlusion had occluded superficial femoral arteries (SFA) demonstrated at the first operation, while 79% of the patients who experienced graft closure had comparable SFA occlusions. Our aggressive approach to graft thrombosis included angiographic study of the inflow arterial system. This revealed that 16% of the failed grafts were associated with hemodynamically significant stenosis of the donor subclavian artery. Our results indicate that AUF bypass is the procedure of choice for unilateral limb ischemia in high-risk patients who require an axillary source and that patency of the SFA does not affect outcome. These results also emphasize the need to obtain angiographic evaluation of the inflow system.

Staging of arterial complications of cervical rib: guidelines for surgical management.

Subclavian artery compression by a cervical rib is an uncommon but potentially disabling condition. A series of 12 patients with 15 arterial lesions is reviewed and a staging system proposed to provide guidelines for managing patients with this condition. Stage I lesions have only arterial stenosis and minor poststenotic dilatation and are managed by thoracic outlet decompression, usually consisting of cervical rib resection. Stage II lesions have intrinsic arterial damage usually with subclavian aneurysm formation and require rib resection, aneurysmectomy, and arterial reconstruction. Stage III lesions present with distal thromboembolic complications and require thrombectomy or embolectomy in addition to thoracic outlet decompression and arterial reconstruction. The anatomic and pathophysiologic bases of the syndrome are reviewed and clinical and angiographic examples of each stage are presented.

Congenital microarteriovenous shunts. Angiographic and Doppler ultrasonographic identification.

We describe herein two cases of vascular malformations, one classified as hemangioma and the other as Klippel-Trenaunay syndrome. Clinical investigation in each case failed to demonstrate the presence of arteriovenous (AV) shunting. Arteriographic findings revealed only indirect evidence of AV shunting in each case. In contrast, systematic scanning with a Doppler ultrasonographic probe of the involved extremities provided evidence of AV shunting and pinpointed it in suspected arteriographic areas. Good correlation between the two methods was confirmed in the hemangioma case both preoperatively and intraoperatively. In the case of Klippel-Trenaunay syndrome, evidence of multiple AV shunts was obtained primarily with Doppler ultrasonography. In addition to arteriography, serial phlebography, when indicated, is also necessary for complete evaluation of concomitant venous malformations. The pathogenic mechanism of these vascular malformations was briefly reviewed, emphasizing AV shunting as a common link between the various anatomicoclinical forms.

Catheterization and angioplasty of the nonopacified peripheral autogenous vein bypass graft.

Nonopacified lower extremity vein bypass grafts may not be thrombosed. Catheterization of these grafts should be performed whenever possible. If graft patency is demonstrated, vein graft angioplasty may restore flow without fibrinolytic therapy. In two cases of nonthrombosed nonopacified grafts, graft patency was demonstrated by catheterization of the grafts, and normal blood flow was restored by percutaneous transluminal angioplasty.

Spontaneous resolution of popliteal artery thrombosis.

Spontaneous resolution of thrombosis of the systemic arteries is a rarely documented phenomenon. Two patients are described in whom thrombus within the popliteal artery was noted to lyse spontaneously. This resulted in a decrease in ischemic symptoms and was documented by angiography. The spontaneous improvement that occurs in some patients with atherosclerotic femoropopliteal disease may be due to this mechanism as well as to increased flow via collateral vessels.

Routine intraoperative angiography. An essential adjunct in vascular surgery.

Intraoperative angiography was performed during a variety of 155 arterial reconstructive procedures including bypass, endarterectomy, embolectomy, thrombectomy, primary reconstruction, and angioplasty. In 27 or 17% of these cases, defects were identified that could be corrected. These included technical errors at the suture line, accumulation of platelet thrombus and atherosclerotic debris, or unrecognized lesions in the runoff. The likelihood of identifying such lesions is greatest in patients undergoing bypass surgery, particularly when the distal anastomosis involves one of the leg arteries. Routine use of intraoperative angiography as an adjunct to vascular surgery is justified and will help to obviate many early graft failures.

Inadequacy of the noninvasive hemodynamic evaluation of percutaneous transluminal angioplasty.

The role of noninvasive hemodynamic tests in the evaluation of percutaneous transluminal angioplasty success or failure was studied. The ankle-brachial pressure index and pulse volume recording amplitude were measured before and after 37 iliac and 46 femoropopliteal angiographically successful percutaneous transluminal angioplasties. Immediate evidence of hemodynamic improvement was seen in 53 percent of angiographically successful dilatations using the ankle-brachial pressure index and in 60 percent using the pulse volume recording amplitude alone. A better correlation was seen when improvement was noted on either test but was still only 71 percent. Twelve primary iliac percutaneous transluminal angioplasties were considered to be successful immediately by angiography, yet no hemodynamic improvement was recorded. Nine primary iliac percutaneous transluminal angioplasties, however, had continued clinical success and limb viability. Twelve angiographically successful femoropopliteal percutaneous transluminal angioplasties also showed no improvement in hemodynamic values, yet three have continued clinical evidence of patency. Thus, although noninvasive hemodynamic tests are important and must be carried out, they are only one of many ways to assess the effectiveness of angioplasty.

Radiology in intestinal ischemia. Angiographic diagnosis and management.

Angiography is an essential component of the diagnosis and treatment of patients with acute and chronic intestinal ischemia. Aortography and selective angiography permit identification of the cause and precise anatomy of intestinal ischemic syndromes, and also help plan their potential correction. Direct intra-arterial infusion of pharmacologic agents into splanchnic vessels has now become part of the therapy of these conditions. This article reviews angiographic techniques and their applications in the management of intestinal ischemic syndromes.

Radiology in intestinal ischemia. Plain film, contrast, and other imaging studies.

Because plain films are usually normal or nonspecific in both colonic and acute mesenteric ischemia, they are not diagnostically helpful. The barium enema is the most useful radiographic examination in the diagnosis of colonic ischemia, and a double-contrast study will show abnormalities in almost all cases. Findings specific for colonic ischemia characteristically change with time. Thumbprinting is the most diagnostic finding; it is seen early in the course of the disease and usually resolves or is replaced within 1 or 2 weeks by an acute ulcerating colitis pattern. The latter may heal over months or go on to stricture formation or a persistent colitis. Nonspecific abnormalities can also be identified on CT and ultrasound, but the incidence of the findings with colonic ischemia is not known. Plain film findings occur late in the course of acute mesenteric ischemia and thus cannot be relied on for the diagnosis, although they may be useful in excluding other conditions. When acute mesenteric ischemia is suspected, angiography should be performed, but CT, ultrasound, and, perhaps, MR imaging may contribute to the diagnosis.

Corticosteroids in clinical and experimental lung transplantation.

Lung allograft rejection can usually be diagnosed by the appearance of infiltrates on plain chest roentgenograms when these are interpreted in the light of other clinical and bacteriologic information. Large pulsed intravenous doses of methylprednisolone were usually effective in reversing lung allograft rejection that occurred in immunosuppressed dogs. In 10 of 15 animals the presence of moderate to severe rejection and its effective reversal with treatment were documented with roentgenograms and histologic sections. This ability to reverse the manifestations of lung allograft rejection, when they occur, has helped in the management of human lung allograft recipients.

Six year experience with expanded polytetrafluoroethylene arterial grafts for limb salvage.

We have used 822 polytetrafluoroethylene (PTFE) grafts in arterial reconstructions for limb salvage over the last 6 years at Montefiore Medical Center-Albert Einstein College of Medicine, Four hundred and twenty-seven femoropopliteal reconstructions with PTFE had a 6 year cumulative life table patency rate of 55% with follow-up of 76 grafts for more than 3 years and 28 grafts for more than 4 years. Seventy-nine bypasses to the isolated popliteal segment had a 6 year cumulative patency rate of 72%. There were 207 bypasses performed to the tibial, peroneal or dorsalis pedis arteries. Life table patency rates were 55% at 1 year, 40% at 2 years and 37% at 4 years. Ninety-two PTFE femorofemoral and 62 axillofemoral bypasses had 5 1/2 year cumulative life table patency rates of 83% and 75%, respectively. Axillopopliteal PTFE bypasses can salvage otherwise doomed limbs. Thirty-four such grafts had 74% 1 year and 45% 5 year patency rates. The overall infection rate in all 822 PTFE grafts was only 0.5%. Thus, PTFE is a promising vascular prosthetic material which facilitates otherwise difficult or impossible limb salvage procedures.

Five year experience with axillopopliteal bypasses for limb salvage.

Over the last 5 years, we have performed 34 axillopopliteal bypasses to salvage threatened limbs of patients in whom standard anatomic or extra-anatomic bypasses had either failed or were not feasible. The indications for these axillopopliteal bypasses, all of which were performed with 6 mm polytetrafluoroethylene grafts, were: (1) severe atherosclerotic disease of the common, superficial and deep femoral arteries which precluded use of these vessels for inflow or outflow for a standard vascular procedure (15 cases); (2) failed aortofemoral bypass with sufficient fibrosis or disease progression in the profunda femoris artery to prevent its use in a reoperation (7 cases); (3) insufficient hemodynamic improvement and failure to heal a foot lesion after an axillofemoral bypass (9 cases); and (4) sepsis in the groin from a previously infected bypass (3 cases). Graft patency was determined by objective measures. Cumulative life table graft patency rates were 77% at 1 year, 51% at 3 years, and 45% at 5 years. Although these rates are not as good as those for our axillofemoral bypasses (75% at 5 years), 22 limbs revascularized by axillopopliteal bypasses were salvaged with function for 1 year and 9 were salvaged with function for 2 years or longer in situations in which no option other than amputation was available. This justifies the continuing use of axillopopliteal bypass in an effort to salvage those limbs imminently threatened with amputation and in which no standard reconstruction is feasible because of disease or infection.

Diagnosis and management of failing lower extremity arterial reconstructions prior to graft occlusion.

In 191 instances, infrainguinal graft occlusion was presumed because of a rethreatened foot, diminished pulses and/or decreased ankle pressure. Routine urgent arteriography revealed 38 instances where the graft was patent (22 vein, 16 PTFE). Ten of these grafts were to the femoral artery, 18 to the popliteal artery and 10 were to infrapopliteal arteries. The deterioration despite a patent graft was due to development of inflow stenosis (15), vein graft lesions (13) or distal disease progression (10). All were treated successfully by percutaneous transluminal angioplasty (30) or simple local operative revisions (8). Cumulative life table patency rates 2 years after reintervention were 89% for failing reconstructions to the femoral artery, 94% for those to the popliteal artery and 89% for infrapopliteal procedures. Comparable rates for limb salvage were 90%, 100% and 100%, respectively. These findings underscore the importance of urgent angiography in suspected lower extremity graft failure. Defects may be detected before real graft occlusion occurs and appropriate interventional treatment can provide important additional periods of limb salvage.

Arterio-venous shunting in renal transplant rejection.

The angiographic appearance of arterio-venous shunting has been reported in one previous case of a patient with acute severe transplant rejection. Two additional cases are presented here. In the first the arteriovenous shunting is massive, and the venous filling is within the first second of the study. In the second the shunting is less severe, and the venous filling occurs later in the arterial phase. Shunting is probably caused by multiple microscopic arterio-venous fistulae secondary to the vasculitis of rejection. We propose that the presence of arterio-venous shunting suggests renal transplant rejection and may indicate a poor prognosis for reversal of this rejection.