Short- and long-term functional effects of percutaneous transluminal angioplasty in hemodialysis vascular access

The efficacy of percutaneous transluminal angioplasty (PTA) is usually expressed as the angiographic result. Access flow (Qa) measurements offer a means to quantify the functional effects. This study was performed to evaluate the short-term functional and angiographic effects of PTA and to determine the longevity of the functional effects during the follow-up period. Patients with an arteriovenous graft (AVG) or an arteriovenous fistula (AVF) who were eligible for PTA (Qa values of <600 ml/min) were included. Ultrasound-dilution Qa measurements were obtained shortly before PTA and periodically after PTA, beginning 1 wk after the procedure. The short-term effects were expressed as the increase in Qa and the reduction of stenosis. The long-term effects were expressed as patency and the decrease in Qa after PTA. Ninety-eight PTA procedures for 60 patients (65 AVG and 33 AVF) were analyzed. Qa improved from 371 +/- 17 to 674 +/- 30 ml/min for AVG and from 304 +/- 24 to 638 +/- 51 ml/min for AVF (both P < 0.0001). In 66% (AVG) and 50% (AVF) of cases, Qa increased to levels of >600 ml/min. The degree of stenosis decreased from 65 +/- 3 to 17 +/- 2% for AVG and from 72 +/- 5 to 23 +/- 7% for AVF (both P < 0.005). The reduction of stenosis was not correlated with DeltaQa (r(2) = 0.066). Six-month unassisted patency rates after PTA were 25% for AVG and 50% for AVF. The decreases in Qa were 3.7 +/- 0.8 ml/min per d for AVG and 1.8 +/- 0.9 ml/min per d for AVF. Qa values before PTA and DeltaQa were correlated with the subsequent decrease in Qa (P < 0.005). In conclusion, Qa increases after PTA but, in a substantial percentage of cases, not to levels of >600 ml/min. Qa values before PTA and the increase in Qa were correlated with long-term outcomes, whereas angiographic results were not. These data, combined with literature data, suggest that there is optimal timing for PTA.     

Distal percutaneous transluminal angioplasty through infrainguinal bypass grafts.

AIM: to evaluate the results of transluminal angioplasty (PTA) performed through infrainguinal bypass grafts for stenotic or occlusive lesions at the distal anastomosis and/or in the runoff arteries. Design: retrospective clinical study. MATERIAL AND METHODS: forty-one patients underwent 57 procedures at the distal anastomosis (n=13), in the runoff arteries (n=32) or at both locations (n=12) at a median of 9.6 months (range, 2-76 months) after infrainguinal bypass grafting. Nineteen procedures were on the popliteal artery, the rest on the crural arteries. Eleven procedures related to occlusions less than 5 cm in length. RESULTS: technical success was achieved in 91%. Primary and primary assisted graft patency rates at 3 years were 32% and 53%, respectively. There were no significant differences in patency rates with regard to the graft material, the type of lesion, the level of PTA, the status of runoff and the use of thrombolysis before PTA. No patients underwent amputation as a direct consequence of failed PTA or graft occlusion. One patient underwent acute surgical intervention due to graft occlusion at the time of attempted PTA. CONCLUSION: the results of PTA at the distal anastomosis and/or in the runoff arteries in limbs with infrainguinal bypass seemed to be inferior to the results of surgical revisions reported in literature. However, as failed PTA did not jeopardise vein-patch angioplasty or jump grafting, it is a reasonable alternative to surgical intervention in selected cases.     

Complications after percutaneous transluminal angioplasty and vascular surgery

Percutaneous transluminal angioplasty (PTA) is an accepted technique in the treatment of occlusive vascular disease. We report complications associated with balloon catheter dilatation and their treatment in the period from 1. 1. 1986 to 31. 3. 1990. Complications were found at the site of dilatation and the site of insertion of the catheter, mostly in the pelvic and femoral region. Surgical correction was successful in all patients, however three patients died postoperatively of acute myocardial ischemia. To avoid these complications close co-operation between the radiologist performing the dilatation and the vascular surgeon managing the complications should be assured.     

Color doppler ultrasonography imaging to guide transluminal angioplasty of venous stenosis

BACKGROUND: The objective of access surveillance is the early recognition of dysfunction in order to be able to correct the stenosis by angioplasty or surgery before access thrombosis occurs. The advent of color Doppler imaging has enabled studies of color Doppler ultrasonography (CDU) for the guidance of percutaneous transluminal angioplasty (PTA). The aim of the present study was to investigate whether color Doppler imaging alone can be safely and effectively used to diagnose vascular graft access stenoses and guide subsequent PTA. METHODS: Using the ultrasound velocity dilution method, we measured access blood flow (Qa) during the first hour of hemodialysis every month in patients with grafts as vascular access. When the decrease in Qa from the baseline value was 40% or more, CDU was performed and immediately followed by PTA in the presence of a stenosis of more than 50%. The Qa was then measured during the first dialysis after PTA and one month later. Repeated-measure analysis of variance was applied to evaluate the early and late (after one month) effect of PTA. RESULTS: Twelve PTAs were performed under CDU guidance in nine patients and led to the elimination of the stenosis or its reduction (two cases). The mean Qa was 809 +/- 263 mL/min at baseline, 468 +/- 153 before PTA, and 820 +/- 281 after PTA. The difference between the pre-PTA and post-PTA values was highly significant (P < 0.001), and the mean value after PTA was not different from baseline (P = 0.672). There were no relevant complications directly related to the procedure. CONCLUSIONS: The CDU procedure is effective for the diagnosis of vascular access stenosis and as a guide during the PTA procedure. It could improve stenosis screening by avoiding the risks of exposure to ionizing radiation and of adverse reactions to contrast media.     

Postcatheterization vascular complications associated with percutaneous transluminal coronary angioplasty

The threat of a vascular complication exists in association with any percutaneous arterial catheterization, but is greater in the more complex interventional techniques. During a 3 1/2-year period from January 1985 through June 1988, 4988 percutaneous transluminal coronary angioplasty procedures were performed at Emory University Hospital. All patients were given heparin during the cardiac intervention, and all had a catheter introducer left in place for several hours after completion of the procedure. Fifty-five iatrogenic vascular complications developed in 52 patients (1%), resulting in 54 corrective operations. Pseudoaneurysm, the most frequent complication, was seen in 35 patients (64%). This was followed by arteriovenous fistula in eight (15%), uncontrolled hemorrhage in six (11%), arterial thrombosis in three (6%), peripheral embolization in two (4%), and bowel ischemia in one patient. The outcome of surgical therapy in the entire group was quite acceptable with no operative mortality, no extremity amputation, and a 7.4% complication rate. Variables that correlated with an increased risk of peripheral vascular problems after percutaneous transluminal coronary angioplasty included advanced age, female gender, thrombolytic therapy, and postprocedural anticoagulation. Variables that did not appear to correlate were hypertension, diabetes, prior percutaneous transluminal coronary angioplasty, antiplatelet therapy, or the size of the guiding catheter used.     

Transluminal angioplasty of venous stenoses in polytetrafluoroethylene vascular access grafts

Since 1984, percutaneous transluminal angioplasty (PTA) utilizing high pressure balloon catheters has been used as an initial approach to restore patency of PTFE (polytetrafluoroethylene, GORE-TEX) hemodialysis vascular access grafts. Seventeen stenotic lesions detected by fistulogram underwent elective PTA. Twelve of these lesions were detected after thrombectomy and five were detected because of increased venous pressures during dialysis. Fourteen attempts at PTA were completely successful in restoring functional patency to the vascular graft. Three attempts were unsuccessful; two of these three grafts were subsequently repaired surgically. Venous stenoses that extended far greater than 6 cm were not considered for PTA. We conclude that PTA is a technique of promise in the non-surgical salvage of failing PTFE grafts. PTA can prolong the useful life of PTFE vascular access grafts and can be performed on an outpatient basis, eliminating the hospitalization that is usually required for surgical revision.     

Percutaneous transluminal angioplasty. An ineffective approach to the failing vascular access

A prosthetic arteriovenous (AV) fistula is often necessary in patients with chronic renal failure who lack suitable venous anatomy for the construction of an autogenous AV access. Not infrequently, these conduits fail as a result of neointimal hyperplasia obstructing the outflow tract at the venous anastomosis. Six patients underwent one or more attempts at balloon dilation of an anastomotic stenosis. Grafts had either thrombosed, exhibited poor arterial inflow, or developed high venous pressures. Eight of ten dilations were outright failures, while two dilations each provided an additional three months of graft function before surgical revision became necessary. We conclude that percutaneous transluminal angioplasty is of very limited value as a salvage procedure in the failing synthetic vascular access, and should be attempted only as a possible temporizing measure in those individuals in whom definitive surgical correction must be delayed.     

Current status of percutaneous transluminal angioplasty

With the development of a dilating balloon catheter that permits percutaneous treatment of many arterial stenoses and some occlusions, a definite advance in the therapy of peripheral vascular disease has been made. It is still too early to be certain what ultimate position this means of therapy will take in the overall treatment of vascular disease, as its use is still being extended and long-term results are not yet clearly known. When compared with surgical therapy, however, it has some striking advantages, although the durability of its effect appears to be less. Despite the fact that more time and experience are needed before its ultimate position is established, we believe that the evidence to date warrants inclusion of this form of therapy in the armamentarium of every major vascular center.     

Morphological changes after percutaneous transluminal angioplasty

BACKGROUND: Percutaneous transluminal angioplasty (PTA) dilates constricted arteries at the circle of Willis to reverse cerebral ischemia caused by cerebral vasospasm. Although 90% of the patients show angiographic improvement after PTA, only 70% show clinical improvement. Why some patients do not improve after PTA is unknown. We report on a 48-year-old woman who failed to improve after PTA and died from aneurysm rerupture. Pathologic studies were performed to determine why PTA failed to reverse the symptoms of cerebral ischemia. METHODS: The arteries of the brain were studied by light microscopy using Gomori's trichrome stain. The arteries were also studied by scanning and transmission electron microscopy. RESULTS: The arteries that were dilated with PTA showed compression of the connective tissue, stretching of the internal elastic lamina, and a combination of compression and stretching of the smooth muscle. The small arteries and arterioles that had been treated with an infusion of intraarterial papaverine were constricted with a thickened intimal layer. CONCLUSION: The persistence of cerebral vasospasm in small and perforating arteries may contribute to the failure of cerebral ischemia to reverse after PTA.     

Outcome in patients with failed percutaneous transluminal angioplasty for peripheral vascular disease

The outcome in 299 patients having 321 percutaneous transluminal angioplasty (PTA) procedures for peripheral vascular disease was analysed. Technical failure occurred in 21 patients (7%) but in none was the limb ischemia made worse by the failed PTA attempt; nine of these (3%) had been considered unsuitable for arterial reconstruction and proceeded to primary amputation, while 12 (4%) did not have subsequent management compromised by the failed PTA attempt. Complications occurred in seven patients (2.3%); four of these (1.3%) had worsening ischemia but were able to be satisfactorily managed by surgical intervention. There were 71 patients (23.7%) who had an initially successful PTA procedure which subsequently failed; 20 of these (6.7%) had been considered unsuitable for arterial reconstruction and proceeded to amputation, while five patients suitable for arterial reconstruction (1.7%) came to amputation, four following failed bypass surgery and one following multiple trauma from a motor vehicle accident. The remaining 46 patients (15.3%) did not have subsequent management compromised by the late failure of PTA. Early and late failure of PTA in patients presenting with peripheral vascular disease does not compromise subsequent management.     

The impact of percutaneous transluminal angioplasty on the management of peripheral vascular disease

Percutaneous transluminal angioplasty is a well established technique with wide application, but its place in the overall management of peripheral vascular disease is not well defined. This study compares similar groups of patients with peripheral vascular disease in 1981 and 1984, before and after the introduction of the technique to a district general hospital. More patients are now being investigated and treated and this is almost entirely due to the availability of angioplasty. The rates for surgery have not changed. Percutaneous transluminal angioplasty should therefore be seen as a new and separate form of treatment for peripheral vascular disease, not necessarily influencing or replacing surgery, and requiring its own allocation of resources in accordance with the increase in the level of care afforded by the technique.     

The changing pattern of vascular surgery: the effect of percutaneous transluminal angioplasty

The pattern of vascular surgery at Westmead Hospital from 1979 to 1985 has been reviewed. There has been an upward trend in the number of patients having repair of abdominal aortic aneurysm and carotid endarterectomy. However, the number of operations for peripheral vascular disease has not increased. This may be due to the increasing use of percutaneous transluminal angioplasty (PTA), but it may also be associated with the increasing difficulty in obtaining hospital admission for patients with conditions not immediately life or limb threatening.     

Septic endarteritis after percutaneous transluminal angioplasty

A case of septic endarteritis leading to septic arthritis and septic emboli occurred after percutaneous transluminal angioplasty. To our knowledge, this is the first reported instance of arterial wall infection potentially caused by percutaneous transluminal angioplasty. Treatment consisted of long-term intravenous antibiotics and drainage of the septic joint.     

Percutaneous transluminal angioplasty as best treatment in stenosis of vascular access for hemodialysis

We show the results of treatment with percutaneous transluminal angioplasty on 38 occasions for vascular access for hemodialysis. Our study includes 22 patients with A-V internal fistulas (Cimino type), 1 autologous saphenous vein shunt and 7 synthetic polytetrafluoro-ethylene shunts. Twenty patients have had a follow-up period over 24 months. Four patients required a second and 2 of them a third transluminal dilatation. Only on two occasions were complications related to the technique. The microscopic findings of the venous wall after percutaneous transluminal angioplasty are shown.