Acute peripheral arterial ischemia: a prospective evaluation of differential management with surgery or thrombolysis

A systematic review and meta-analysis of endovascular and surgical revascularization techniques in acute limb ischemia

BACKGROUND

The initial treatment of patients with acute limb ischemia (ALI) remains undefined. The aim of this article was to compare the safety and effectiveness of catheter-driven thrombolysis (CDT) with surgical revascularization and evaluate the various fibrinolytic agents, endovascular, and pharmacochemical approaches that aim for thrombectomy.

METHODS

PubMed, Embase, and the Cochrane Library were searched for studies on the management of ALI by means of surgical or endovascular recanalization, returning 520 studies. All randomized, controlled trials, nonrandomized prospective, and retrospective studies were included comparing treatment of ALI.

RESULTS

Twenty-five studies, investigating a total of 4689 patients, were included for meta-analysis spread across nine different comparisons. No differences were found in limb salvage between thrombectomy and thrombolysis. More major vascular events were seen in the thrombolysis group (6.5% compared with 4.4% in the surgically treated group; odds ratio [OR], 0.33; 95% confidence interval [CI], 0.13-0.87; P = .02; I² = 20%). Comparable limb salvage was found for high- and low-dose recombinant tissue plasminogen activator (r-tPA). No significant differences were found in major vascular event between low r-tPA (14%) and high r-tPA (10.5%; P = .13). The 30-day limb salvage rate was 79.7% for r-tPA treatment and 60.4% for streptokinase (OR, 3.14; 95% CI, 1.26-7.85; P = .01; I² = 0%). AngioJet showed more limb salvage at 6 months compared with r-tPa (OR, 2.21; 95% CI, 1.17-4.18; P = .01; I² = 0%).

CONCLUSIONS

Both CDT and surgery have comparable limb salvage rates in patients with ALI; however, CDT is associated with a higher risk of hemorrhagic complications. No conclusions can be drawn regarding the risk of hemorrhagic complications regarding thrombolytic therapy by means of r-tPA, streptokinase, or urokinase. Insufficient data are available to conclude the preference of using a hybrid approach, ultrasound-accelerated CDT, heated r-tPA. or novel endovascular (rheolytical) thrombectomy systems. Future trials regarding ALI need to be constructed carefully, ensuring comparable study groups, and should follow standardized practices of outcome reporting.

Intraoperative Digital Subtraction Angiography after Thromboembolectomy: Preliminary Experience

Purpose:

To evaluate the potential influence of intraoperative digital subtraction angiography (DSA) on surgical strategy after balloon thromboembolectomy for acute lower limb ischemia.

Methods:

Thirty-six consecutive patients with critical limb ischemia were treated with balloon catheter thromboembolectomy assessed by intraoperative digital subtraction angiography. The need for further intervention was determined by the surgeon based on the DSA information. Primary completion DSAs were made in every procedure; subsequent completion DSAs were performed after reinterventions at the discretion of the surgeon.

Results:

Initial treatment in this patient group consisted of 14 embolectomies and 26 thrombectomies. From the completion DSAs of these 40 procedures, a reintervention was judged necessary in 27 (68%). Of these 27 reinterventions, 17 underwent a secondary DSA; evidence supporting a third intervention was found in 11 (64%). Overall, a total of 69 DSAs were performed in these patients. Mortality was 22% (8 patients); 38% (5) in embolectomy patients and 13% (3) in the thrombectomy cohort. Eighty-eight percent of the embolectomy survivors had an uneventful recovery, while only 25% of the thrombectomy survivors experienced an uncomplicated follow-up. In one quarter of the surviving thrombectomy patients, a surgical revascularization resulted in limb salvage; in 45%, a major amputation was the outcome.

Conclusions:

In this study, the completeness of balloon catheter thromboembolectomy was assessed by intraoperative DSA. As a result, 68% of the procedures required one or more reinterventions for residual lesions. Intraoperative DSA is a simple and quick technique that may be a promising adjunct to intraoperative balloon thromboembolectomy.

Controlled Reperfusion Versus Conventional Treatment of the Acutely Ischemic Limb

Background—

Amputation rates and mortality in patients with severe acute limb ischemia remain high. The protective effect of controlled reperfusion (CR) on tissue damage because of local and systemic reperfusion injury is unclear.

Methods and Results—

A total of 174 patients from 14 centers were randomized between conventional treatment (CT) by thrombembolectomy and normal blood reperfusion and thrombembolectomy followed by CR. The primary end point was amputation-free survival (AFS) after 4 weeks (CT, 82.4%; CR, 82.6%). Secondary end points were AFS (CT, 62.4%; CR, 63.1%) and overall survival (CT, 71.6%; CR, 76.3%) after 1 year. Analysis of the prognostic effects of preoperative factors revealed a strong adverse effect of bilateral involvement on AFS. In the subgroup with unilateral ischemia (n=160), age >80 years and central localization of the occlusion had independent negative prognostic effects on AFS. In the per-protocol population of 104 patients with unilateral ischemia, treatment per protocol, and successful revascularization, amputation or death within 4 weeks occurred in only 8% as compared with 33% in patients not fulfilling these criteria. No differences between treatment groups CT and CR were found, neither overall nor in the per-protocol population nor in patient subgroups defined by other pre- and intraoperative factors.

Conclusions—

Similar AFS in patients with CT or with CR was observed in this large randomized multicenter trial.

Clinical Trial Registration—

URL: http://www.drks.de . Unique identifier: DRKS00000579.

Regional vascular surgical units: a practical means of providing specialist services

BACKGROUND

A comprehensive regional emergency and elective vascular surgical service was established in Limerick Regional General Hospital between 1994 and 1996 following the appointment of three surgeons with vascular training.

AIM

To compare vascular surgical activity before and after the establishment of a regional vascular service.

METHODS

This study used local and national computerised databases, clinic letters, theatre registers and radiology records to compare vascular surgical activity before (1992) and after (1997) this service was established.

RESULTS

Total outpatient activity increased almost six-fold and total number of inpatient vascular procedures (including radiological) increased from 146 to 432, but the venous proportion declined from 70% to 36%. The number of major arterial procedures increased from 37 to 165 in 1997 including 10 carotid endarterectomies, 24 aortic reconstructions and 54 lower limb reconstructions representing rates of 3/100,000, 8/100,000 and 17/100,000 population respectively.

CONCLUSION

As substantial changes in disease patterns are unlikely, these data indicate that patients previously diverted elsewhere for therapy are now cared for within the health board region and that further increases in workload may be expected. We suggest that these data mandate the reallocation of resources to fund appropriately staffed and audited regional vascular units.

Peripheral thrombolysis for acute-onset claudication. Thrombolysis Study Group

BACKGROUND

The aim of this study was to determine the outcome of patients who presented with sudden onset of incapacitating claudication of less than 2 weeks' duration and who were treated with peripheral arterial thrombolysis.

METHODS

The database of the Thrombolysis Study Group was searched retrospectively for patients who received thrombolysis for acute-onset claudication. Some 108 patients (65 men, median age 69 (range 29-94) years) were treated with intra-arterial tissue plasminogen activator at 14 hospitals. The median duration of symptoms was 72 h (range from 2 h to 2 weeks). There were 52 graft and 56 native vessel arterial occlusions.

RESULTS

The immediate outcome of thrombolysis for native vessel arterial occlusion was thrombus clearance in 50 patients (89 per cent) and failed lysis in six (11 per cent). Thirty-six patients (64 per cent) had a secondary radiological or surgical procedure carried out after lysis. After 30 days four patients (7 per cent) had a major amputation, eight (14 per cent) had died, 38 (68 per cent) were symptom free and seven (12 per cent) continued to have claudication. Three patients (5 per cent) suffered a major haemorrhage. The immediate outcome of thrombolysis for graft occlusion was thrombus clearance in 48 patients (92 per cent) and failed lysis in four (8 per cent); 27 patients (52 per cent) had a secondary procedure. After 30 days four patients (8 per cent) had a major amputation, seven (13 per cent) had died, 32 (62 per cent) were symptom free and nine (17 per cent) had persistent claudication. Three patients (6 per cent) suffered a major haemorrhage.

CONCLUSION

Patients who presented with acute onset of incapacitating claudication had an outcome similar to that after thrombolysis for critical ischaemia. It is recommended that patients who present in this way should be observed and treated with thrombolysis only if they progress to critical ischaemia. Presented to the Association of Surgeons of Great Britain and Ireland, Edinburgh, UK, May 1998, and published in abstract form as Br J Surg 1998; 85(Suppl 1): 24

Management of acute leg ischaemia in the elderly

BACKGROUND

Peripheral thrombolysis is advocated by some as the best initial treatment for acute leg ischaemia; but this may not be true for elderly patients. This study reviewed the management of acute leg ischaemia in patients aged over 75 years.

METHODS

Over a 5-year interval, 91 events of acute leg ischaemia in 84 patients were managed in a single district general hospital according to a local protocol. There were 60 women and 24 men of median age 81 (range 75-100) years. Fifteen patients were too elderly and infirm for active treatment and received anticoagulation alone. Some 76 events (84 per cent) occurred in patients suitable for active therapy: 33 were managed by initial surgery and 43 by peripheral thrombolysis with tissue plasminogen activator.

RESULTS

Overall outcome after 30 days was limb salvage in 48 (53 per cent), amputation in five (5 per cent) and death in 38 (42 per cent). In actively treated patients the corresponding values were 43 (57 per cent), four (5 per cent) and 29 (38 per cent). Initial successful revascularization was more likely following surgery (29 of 33 versus 25 of 43 events with thrombolysis, P < 0.01), but the 30-day outcome was similar in the actively treated groups owing to subsequent morbidity and mortality.

CONCLUSION

A group of patients (mostly women) with emboli could be identified, using clinical criteria, who had a high chance of successful revascularization following embolectomy. Late outcome remained poor due to associated co-morbid conditions. Thrombolysis is associated with substantial risk in the elderly, and with high complication rates.

The role of thrombolysis in the management of thromboembolic disorders: a four-year review

OBJECTIVE

To examine the role of thrombolysis alone, or in conjunction with surgery and angioplasty, in the treatment of thromboembolic disorders.

DESIGN

A retrospective review of 70 patients, who received thrombolysis on 73 occasions between 1990 and 1993.

PATIENTS AND METHODS

Four groups were defined: (1) thrombolysis alone (40%); (2) thrombolysis followed by angioplasty (23%); (3) thrombolysis followed by surgery (13%) and (4) thrombolysis after failed angioplasty (24%).

RESULTS

Twenty-eight patients (40%) received thrombolysis alone of which 13 were successful. In 25 cases (36%) thrombolysis was initially successful in that it permitted further angioplasty or surgical reconstruction. This adjunctive treatment was successful in 16 cases. Overall, when used as a first-line treatment, thrombolysis was successful in 72% of cases. Success in this context includes those in which a further procedure was possible after thrombolysis. These groups included 20 occluded grafts in which thrombolysis played an important part in unblocking 13 (65%) of them. In a separate group of 17 patients (24%) thrombolysis was given after failed angioplasty and was successful on 15 (88%) occasions. Local complications occurred in 17 patients. There were three deaths. There were no intra-cerebral haemorrhages.

CONCLUSIONS

Thrombolysis alone can be used successfully. There is a large group in which thrombolysis can help to increase the success rate of interventional radiology.

Intraoperative digital subtraction angiography after thromboembolectomy: preliminary experience

PURPOSE

To evaluate the potential influence of intraoperative digital subtraction angiography (DSA) on surgical strategy after balloon thromboembolectomy for acute lower limb ischemia.

METHODS

Thirty-six consecutive patients with critical limb ischemia were treated with balloon catheter thromboembolectomy assessed by intraoperative digital subtraction angiography. The need for further intervention was determined by the surgeon based on the DSA information. Primary completion DSAs were made in every procedure; subsequent completion DSAs were performed after reinterventions at the discretion of the surgeon.

RESULTS

Initial treatment in this patient group consisted of 14 embolectomies and 26 thrombectomies. From the completion DSAs of these 40 procedures, a reintervention was judged necessary in 27 (68%). Of these 27 reinterventions, 17 underwent a secondary DSA; evidence supporting a third intervention was found in 11 (64%). Overall, a total of 69 DSAs were performed in these patients. Mortality was 22% (8 patients); 38% (5) in embolectomy patients and 13% (3) in the thrombectomy cohort. Eighty-eight percent of the embolectomy survivors had an uneventful recovery, while only 25% of the thrombectomy survivors experienced an uncomplicated follow-up. In one quarter of the surviving thrombectomy patients, a surgical revascularization resulted in limb salvage; in 45%, a major amputation was the outcome.

CONCLUSIONS

In this study, the completeness of balloon catheter thromboembolectomy was assessed by intraoperative DSA. As a result, 68% of the procedures required one or more reinterventions for residual lesions. Intraoperative DSA is a simple and quick technique that may be a promising adjunct to intraoperative balloon thromboembolectomy.

Lower limb intra-arterial thrombolysis

In the UK, approximately 5000 patients present annually with acute lower limb ischaemia. The aetiology is usually thromboembolic disease, other causes include aortic dissection and arterial trauma. Over the past two decades thrombosis has replaced embolism as the principal cause of acute ischaemia, and now accounts for approximately 59% of cases. As a consequence, intra-arterial thrombolysis is being increasingly used as first-line treatment for this condition.

Immediate and early follow-up results of purse spray thrombolysis in patients with peripheral ischaemia

Pulse spray thrombolysis is a technique of accelerated peripheral thrombolysis which has been evaluated in 38 patients, 29 with threatened limb viability and nine with a viable but critically ischaemic limb. The median length of occlusion was 26.5 (range 3-65) cm. The lytic agent used was recombinant tissue plasminogen activator (rtPA), injected manually via a pulse spray catheter at a concentration of 0.33 mg/ml and a bolus size of 0.2 ml. The median total dose of rtPA was 18 (range 5-35)mg. Patency and flow were completely restored in 34 of 38 patients and clinical success at 30 days was maintained in 27 of 38. The median lysis time was 120 (range 35-1125) min, compared with a median duration of 1545 (range 42-5760) min in 120 consecutive patients previously treated with conventional low-dose infusion thrombolysis using rtPA. This represents a 12-fold reduction in lysis time (P < 0.001). The overall estimated cumulative limb salvage rate for the 38 patients who entered the study was 84 per cent and the cumulative patency rate for the 34 patients in whom patency was restored was 74 per cent at 18 months follow-up. Pulse spray thrombolysis rapidly restores patency with good limb salvage at 30 days; the benefit is sustained even in patients with limbs at immediate risk of irreversible ischaemic injury who are not considered suitable for conventional thrombolysis.

Arterial emboli of the lower limbs: analysis of risk factors for mortality and amputation. Association Universitaire de Recherche en Chirurgie

To evaluate risk factors for mortality and amputation after arterial embolism of the lower limbs, we reviewed the records of 397 patients (201 men [mean age 69 +/- 14 years] and 196 women [mean age 79 +/- 12 years]) who were enrolled in a prospective study. The degree of ischemia was rated as follows: grade I in 26% of patients, grade II in 46%, and grade III in 27%. Among patients with complete obstruction, the emboli were located above the inguinal ligament in 213 limbs (46%), in the superficial or popliteal artery in 196 (43%), and at the infrapopliteal level in four (3%). The emboli were bilateral in 59 cases (15%). In 11% of patients the emboli also involved either an upper limb or a visceral or cerebral artery. The origin of the embolus was the heart in 55% of patients, an artery in 12%, and was unknown in the remaining cases. Two hundred two patients (50%) had arterial fibrillation, 33 (8%) had cardiac conduction abnormalities, 186 (47%) had ischemic heart disease, 55 (14%) had valvular heart disease, and 43 (11%) had cardiac insufficiency. The in-hospital mortality rate was 15% (n = 60) and major amputations or severe ischemic sequelae were observed in 23% (n = 91). Logistic regression analysis revealed four independent preoperative factors associated with a significantly higher risk of death: associated visceral emboli with a relative risk (RR) of 6.7 (p < 0.001), invalidism with an RR of 4.3 (p < 0.001), cardiac insufficiency with an RR of 2.4 (p = 0.001), and creatinemia > 180 ml/L with an RR of 2.1 (p = 0.01). The variables associated with an increased risk of amputation were invalidism (p = 0.001), severity of ischemia (p = 0.001), infrapopliteal location of the embolus (p = 0.001), delay of more than 12 hours before treatment of severe ischemia was initiated (p = 0.01), failure to restore arterial patency (p = 0.001), and postoperative cardiac complications (p = 0.01).

Provision of vascular surgical services in the Oxford Region

Vascular surgical practice across an entire health region was studied. There was a mean of 115.9 inpatient episodes and 46.9 vascular reconstructions per 100,000 population, with considerable variation between districts. Vein utilization for infrainguinal grafts was greater in the teaching hospital and few femorodistal grafts or carotid endarterectomies were carried out elsewhere; there were few tertiary referrals of elective vascular cases. Only two districts have formal arrangements for emergency vascular 'on-call'. There is marked inequality of provision of vascular surgical services across the region.

The treatment of upper limb vascular occlusions using intraarterial thrombolysis

Acute ischaemia of the lower limb is increasingly treated by intraarterial thrombolysis. Four cases are reported in which this technique has been used successfully for treatment of upper limb emboli. The possible indications and potential drawbacks of such treatment are discussed.

Early results and 1-year follow-up after intra-arterial thrombolysis

Intra-arterial thrombolysis (IAT) was used as first-line treatment for 100 occlusions causing acute, subacute or chronic ischaemia. Streptokinase was used in 90 cases and tissue plasminogen activator in the remaining ten. Complete lysis, as determined radiologically, was achieved in 55 per cent of cases and partial lysis in 20 per cent. Lysis was more effective the earlier it was used. Major complications occurred in seven cases: five patients suffered major haemorrhage, two of whom died, and two had haemorrhagic cerebrovascular accidents. Of the patients with complete or partial clearance of thrombosis, 19 had no underlying apparent cause, 23 underwent angioplasty and 15 had an operation. The 1-year patency rate following complete lysis was 58 per cent. The 1-year patency rate after successful treatment commencing within 1 week of symptoms starting was 71 per cent, compared with 36 per cent for later treatment. Aortofemoral bifurcation grafts were cleared in three of five cases and all remain patent. Eight popliteal aneurysms were demonstrated by IAT and were ligated and bypassed; all these grafts remained patent at follow-up. IAT is less effective in chronic than acute occlusion. It should be reserved for patients in whom the occlusion is of short duration or for those with a thrombosed aortofemoral bifurcation graft or popliteal aneurysm.

Low-dose intra-arterial thrombolysis in the treatment of occluded vascular grafts

As the use of intra-arterial thrombolysis increases, its application to specific areas requires definition. The results of treatment of occluded vascular grafts are presented. Thrombolysis using streptokinase or tissue plasminogen activator was planned in the treatment of 18 occluded vascular grafts (five aortofemoral bifurcation grafts and 13 infrainguinal grafts). Two patients, both with infrainguinal occlusions, did not receive thrombolytic therapy and were considered failures of treatment. Successful lysis occurred in three of five aortofemoral grafts, in both infrainguinal vein grafts and in five of nine infrainguinal synthetic grafts. The overall success rate was approximately 60 per cent. Two-thirds of the patients required no intervention following successful lysis. Percutaneous transluminal angioplasty was not found to be a useful additional procedure. A review of the literature revealed that intra-arterial thrombolysis is significantly more successful in the treatment of suprainguinal graft occlusion than in infrainguinal occlusions, there being no difference between infrainguinal vein and synthetic grafts. Provided that the limb is viable and there are no contraindications, intra-arterial thrombolysis is a useful means of clearing occluded grafts.

Limitations to the widespread usage of low-dose intra-arterial thrombolysis

Despite encouraging results, intra-arterial thrombolysis (IAT) has not been readily accepted by British surgeons. In an attempt to clarify the reasons for this we sent a postal questionnaire to surgeons with a vascular interest, asking them to define their present attitude towards IAT. Subsequently, we re-analysed our own clinical data in the light of the answers received. In all 134 surgeons (58%) replied to the questionnaire; 48 (38%) never used IAT and 56 (45%) used it only occasionally. When stated, the main reasons for this limited use were the doubts about efficacy (45%) and lack of radiological support (47%). From November 1988 to August 1990 we used IAT for 82 occlusions (streptokinase 74, rt-PA8). Lysis was achieved in 82% of cases when treatment was started within 1 week of symptoms starting, and 62% with symptoms of longer duration. Following successful IAT no further treatment was required in 44% of cases, reconstruction was needed in 26% and angioplasty in 23%, one major amputation was performed. Unsuccessful lysis resulted in reconstruction in 40% of cases. Overall, the limb salvage rate was 89%. Major complications occurred in six cases. One patient sustained a fatal CVA and five bled from the catheter insertion site. Two of these patients required an emergency operation and one other, who had an angioplasty immediately following lysis, died. Minor complications included local haematoma formation (16), catheter problems (6), and allergic reactions (2). After insertion of the perfusing catheter, angiograms (median 4, maximum 10) were performed at intervals, with repositioning of the catheter if necessary, until lysis was complete.(ABSTRACT TRUNCATED AT 250 WORDS)

Thrombolytic therapy in the management of acute limb ischaemia

Acute limb ischaemia poses a threat to both the limb and life of a patient. Until recently, attempted revascularization by thromboembolectomy or vascular reconstruction held the best chance of limb salvage. Thrombolytic techniques afford an alternative method of management for this condition and are effective in selected patients. Low-dose intra-arterial streptokinase is the most established method of thrombolysis, although the recently developed tissue plasminogen activator offers a promising alternative. Intra-arterial thrombolysis is not an easy option, being labour intensive and requiring close co-operation between surgeon and radiologist. Thrombolytic and surgical techniques are not mutually exclusive but are best used to complement each other. Ideally patients with acute limb ischaemia should be managed by surgeons with knowledge of, and access to, optimal current surgical and non-surgical techniques.