Percutaneous thrombectomy or ultrasound-accelerated thrombolysis for initial management of acute limb ischaemia

Paradigm Shift of Interventional Strategies and Outcomes for Acute Limb Ischemia Post-Pandemic

PURPOSE

We performed a large-scale comparison of patients treated for acute limb ischemia (ALI) in the pre-COVID (2017-2019) and COVID (2020-2022) eras to evaluate changes in interventional strategies and compare factors associated with adverse outcomes. We sought to characterize patient outcomes in an evolving ALI treatment algorithm in response to pandemic-associated presentation delays and rapid technological advancements in mechanical thrombectomy (MT).

METHODS

Using the TriNetX global research network, we conducted a multicenter query across 80 health care organizations (HCOs) spanning 4 countries for patients treated for ALI. Propensity score matching was performed to account for comorbidities. Risk of adverse outcomes within 30 days was calculated for each era, including re-intervention (RI30), major/minor amputation, and death. Patients were then stratified by initial intervention: open revascularization (OR), MT, or catheter-directed thrombolysis and adjunctive endovascular procedures alone (CDT/EP). Risk of adverse outcomes was compared between treatment groups of the same era.

RESULTS

After propensity score matching, the pre-COVID era and COVID era cohorts included 7344 patients each. COVID era patients experienced a statistically significant higher risk of 30-day mortality (RR=1.211, p=0.027). Mechanical thrombectomy interventions were performed more frequently in the COVID era (RR=1.314, p<0.0001). Comparing outcomes between treatment groups, MT patients required RI30 more than OR patients (pre-COVID: RR=2.074, p=0.006; COVID: RR=1.600, p=0.025). Open revascularization patients had higher 30-day mortality (pre-COVID: RR=2.368, p<0.0001; COVID: RR=2.013, p<0.0001) and major amputations (pre-COVID: RR=2.432, p<0.0001; COVID: RR=2.176, p<0.0001) than CDT/EP. Pre-COVID CDT/EP patients were at higher risk for RI30 (RR=1.449, p=0.005) and minor amputations (RR=1.500, p=0.010) than OR. The MT group had higher major amputation rates than CDT/EP (pre-COVID: RR=2.043, p=0.019; COVID: RR=1.914, p=0.007). COVID-era MT patients had greater 30-day mortality (RR=1.706, p=0.031) and RI30 (RR=1.544, p=0.029) than CDT/EP.

CONCLUSION

Significant shifts toward an MT-based approach have been observed in the last 3 years. Although MT required more RI30 than OR, there was no associated consequence of mortality and limb salvage. The increased mortality seen among COVID-era patients could be explained by delayed presentation, as well as poorly understood pro-thrombogenic or pro-inflammatory mechanisms related to the first waves of COVID. More research is necessary to determine an optimal treatment algorithm.

CLINICAL IMPACT

Comorbid risk factors and severity of ischemia must be carefully considered before selecting an interventional strategy to prevent adverse outcomes and maximize limb salvage. Open revascularization strategies are associated with increased mortality and limb loss compared to less-invasive thrombolytic therapy alone. Mechanical thrombectomy (MT)-based approaches have been increasingly used in the last 3 years. Patients receiving MT are more likely to require reintervention within 30 days.

Availability of evidence and comparative effectiveness for surgical versus drug interventions: an overview of systematic reviews and meta-analyses

OBJECTIVES

This study aims to examine the prevalence of comparisons of surgery to drug regimens, the strength of evidence of such comparisons and whether surgery or the drug intervention was favoured.

DESIGN

Systematic review of systematic reviews (umbrella review).

DATA SOURCES

Cochrane Database of Systematic Reviews.

ELIGIBILITY CRITERIA

Systematic reviews attempt to compare surgical to drug interventions.

DATA EXTRACTION

We extracted whether the review found any randomised controlled trials (RCTs) for eligible comparisons. Individual trial results were extracted directly from the systematic review.

SYNTHESIS

The outcomes of each meta-analysis were resynthesised into random-effects meta-analyses. Egger's test and excess significance were assessed.

RESULTS

Overall, 188 systematic reviews intended to compare surgery versus drugs. Only 41 included data from at least one RCT (total, 165 RCTs) and covered a total of 103 different outcomes of various comparisons of surgery versus drugs. A GRADE assessment was performed by the Cochrane reviewers for 87 (83%) outcomes in the reviews, indicating the strength of evidence was high in 4 outcomes (4%), moderate in 22 (21%), low in 27 (26%) and very low in 33 (32%). Based on 95% CIs, the surgical intervention was favoured in 38/103 (37%), and the drugs were favoured in 13/103 (13%) outcomes. Of the outcomes with high GRADE rating, only one showed conclusive superiority in our reanalysis (sphincterotomy was better than medical therapy for anal fissure). Of the 22 outcomes with moderate GRADE rating, 6 (27%) were inconclusive, 14 (64%) were in favour of surgery and 2 (9%) were in favour of drugs. There was no evidence of excess significance.

CONCLUSIONS

Though the relative merits of surgical versus drug interventions are important to know for many diseases, high strength randomised evidence is rare. More randomised trials comparing surgery to drug interventions are needed.

Observation of the effect of angiojet to treat acute lower extremity arterial embolization

BACKGROUND

Through significant advances in the treatment of peripheral arterial occlusive disease, acute ischemia of the lower extremity is still associated with significant morbidity, limb threat and mortality. The two main causes of acute ischemia in lower extremities are arterial embolism and atherosclerotic arteries. Timely recognition and treatment of acute limb ischemia in emergency situations is essential in order to minimize the duration of ischemia.

AIM

To investigate the application effect of angiojet thrombolysis in the treatment of acute lower extremity arterial embolization.

METHODS

Sixty-two patients with acute lower extremity arterial embolization admitted to our hospital from May 2018 to May 2020 were selected. Among them, the observation group (twenty-eight cases) had received angiojet thrombolysis, and the control group (thirty-four cases) had received femoral artery incision and thrombectomy. After thrombus clearance, significant residual stenosis of the lumen was combined with balloon dilation and/or stent implantation. When the thrombus removal was not satisfactory, catheter-directed thrombolysis was performed. The incidence of postoperative complications, recurrence rate and recovery of the two groups were compared.

RESULTS

There were no significant differences in postoperative recurrence (target vessel reconstruction rate), anklebrachial index and the incidence of postoperative complications between the two groups (P > 0.05); there were statistically significant differences in postoperative pain score and postoperative rehabilitation between the two groups (P < 0.05).

CONCLUSION

The application of angiojet in the treatment of acute lower limb artery thromboembolism disease is safe and effective, minimally invasive, quicker recovery after operation, less postoperative complications, which is more suitable for the treatment of femoral popliteal arterial thromboembolism lesions. If the thrombus removal is not satisfactory, the combination of coronary artery aspiration catheter and catheterized directed thrombolysis can be used. Balloon dilation and stent implantation can be considered for obvious lumen stenosis.

Availability of evidence and comparative effectiveness for surgical versus drug interventions: an overview of systematic reviews

Objectives

To examine the prevalence of comparisons of surgery to drug regimens, the strength of evidence of such comparisons, and whether surgery or the drug intervention was favored.

Design

Systematic review of systematic reviews (umbrella review).

Data sources

Cochrane Database of Systematic Reviews (CDSR).

Eligibility criteria and synthesis of results

Using the search term "surg*" in CDSR, we retrieved systematic reviews of surgical interventions. Abstracts were subsequently screened to find systematic reviews that aimed to compare surgical to drug interventions; and then, among them, those that included any randomized controlled trials (RCTs) for such comparisons. Trial results data were extracted manually and synthesized into random-effects meta-analyses.

Results

Overall, 188 systematic reviews intended to compare surgery versus drugs. Only 41 included data from at least one RCT (total, 165 RCTs with data) and covered a total of 103 different outcomes of various comparisons of surgery versus drugs. A GRADE assessment was performed by the Cochrane reviewers for 87 (83%) outcomes in the reviews, indicating the strength of evidence was high in 4 outcomes (4%), moderate in 22 (21%), low in 27 (26%) and very low in 33 (32%). Based on 95% confidence intervals, the surgical intervention was favored in 38/103 (37%), and the drugs were favored in 13/103 (13%) outcomes. Of the outcomes with high GRADE rating, only one showed conclusive superiority (sphincterotomy was better than medical therapy for anal fissure). Of the 22 outcomes with moderate GRADE rating, 6 (27%) were inconclusive, 14 (64%) were in favor of surgery, and 2 (9%) were in favor of drugs.

Conclusions

Though the relative merits of surgical versus drug interventions are important to know for many diseases, high strength randomized evidence is rare. More randomized trials comparing surgery to drug interventions are needed.

Protocol registration

https://osf.io/p9x3j.

Percutaneous mechanical thrombectomy using the Rotarex®S device for the treatment of acute lower limb artery embolism: A retrospective single-center, single-arm study

OBJECTIVE

Acute limb embolism (ALE) is a challenging, highly morbid, and frequently fatal vascular emergency. Percutaneous mechanical thrombectomy (PMT) devices are an alternative treatment to restore perfusion by removing emboli in the limb arterial system. We evaluated the outcomes of treatment of ALE patients using PMT devices in our center.

METHODS

A retrospective review of ALE patients treated with Rotarex S (Straub Medical) at a single institution from 2018 to 2022 was performed. The primary outcome was technical success, defined as complete recanalization of the occluded segment with satisfactory outflow and good capillary filling of the distal parts of the foot without any major or obstructing residual emboli or thrombi either in the treated segment or in the outflow tract without the need for additional catheter-directed thrombolysis (CDT) or conversion to open surgery. Embolized segments treated, treatment outcomes, and perioperative complications were reviewed.

RESULTS

A total of 17 ALE patients (29% men, 71% women; mean age, 73 years) underwent PMT procedures. The femoral arteries and popliteal arteries are the most commonly treated vessels, with both present in 59% of the patients. The technical success rate was 100%, but the majority of cases (82%) had concurrent percutaneous transluminal angioplasty or stent grafting, and two patients were treated with urokinase during the operation. There was one thrombotic recurrence that required amputation. There were no 30-day deaths. Complications included extravasation after PMT (two), intraoperative embolization of the outflow tract (one), access site hematoma (one), target artery thrombosis (one), and acute kidney injury (one). There were no severe bleeding complications.

CONCLUSIONS

The Rotarex S device has a satisfactory success rate, although complementary use of various adjunctive techniques is frequently required. It seems to be a moderately effective tool for treating ALE to avoid CDT or open surgery. The device appears safe, with low risks of amputation and mortality rates, but special attention should be given to the potential for extravasation and distal embolism.

Percutaneous thrombectomy or ultrasound-accelerated thrombolysis for initial management of acute limb ischaemia

BACKGROUND

Acute limb ischaemia (ALI), the sudden and significant reduction of blood flow to the limb, is considered a vascular emergency. In the general population, the incidence is estimated as 14 per 100,000. Prognosis depends on the time it takes to diagnose the condition and begin appropriate treatment. Standard initial interventional treatments include conventional open surgery and endovascular interventions such as catheter-directed thrombolysis (CDT). Percutaneous interventions, such as percutaneous thrombectomy (PT, including mechanical thrombectomy or pharmomechanical thrombectomy) and ultrasound-accelerated thrombolysis (USAT), are also performed as alternative endovascular techniques. The proposed advantages of PT and USAT include reduced time to revascularisation and when combined with catheter-directed thrombolysis, a reduction in dose of thrombolytic agents and infusion time. The benefits of PT or USAT versus open surgery or thrombolysis alone are still uncertain. In this review, we compared PT or USAT against standard treatment for ALI, in an attempt to determine if any technique is comparatively safer and more effective.

OBJECTIVES

To assess the safety and effectiveness of percutaneous thrombectomy or ultrasound-accelerated thrombolysis for the initial management of acute limb ischaemia in adults.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, the World Health Organization (WHO) International Clinical Trials Registry Platform, and ClinicalTrials.gov to 3 March 2021. We searched reference lists of relevant studies and papers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared PT (any modality, including mechanical thrombectomy (aspiration, rheolysis, rotation) or pharmomechanical thrombectomy) or USAT with open surgery, thrombolysis alone, no treatment, or another PT modality for the treatment of ALI.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies, assessed risk of bias, extracted data, performed data analysis, and assessed the certainty of evidence according to GRADE. Outcomes of interest were primary patency, amputation rate, major bleeding, clinical success, secondary patency, and adverse effects.

MAIN RESULTS

We included one RCT in this review. This study had a total of 60 participants and compared USAT with standard treatment (CDT). The study included 32 participants in the CDT group and 28 participants in the USAT group. We found no evidence of a difference between USAT and CDT alone for the following evaluated outcomes: amputation rate (risk ratio (RR) 1.14, 95% confidence interval (CI) 0.17 to 7.59); major bleeding (RR 1.71, 95% CI 0.31 to 9.53); clinical success (RR 1.00, 95% CI 0.94 to 1.07); and adverse effects (RR 5.69, 95% CI 0.28 to 113.72). We rated the certainty of the evidence as very low for these outcomes. We downgraded the certainty of the evidence for amputation rate, major bleeding, clinical success, and adverse effects by two levels due to serious limitations in the design (there was a high risk of bias in critical domains) and by two further levels due to imprecision (a small number of participants and only one study included). The study authors reported 30-day patency, but did not report primary and secondary patency separately. The patency rate in the successfully lysed participants was 71% (15/21) in the USAT group and 82% (22/27) in the CDT group. The study authors did not directly report secondary patency, which is patency after secondary procedures, but they did report on secondary procedures. Secondary procedures were subdivided into embolectomy and bypass grafting. Embolectomy was performed on 14% (4/28) of participants in the USAT group versus 3% (1/32) of participants in the CDT group. Bypass grafting was performed on 4% (1/28) of participants in the USAT group versus 0% in the CDT group. As we did not have access to the specific participant data, it was not possible to assess these outcomes further. We did not identify studies comparing the other planned interventions.

AUTHORS' CONCLUSIONS

There is insufficient evidence to assess the safety and effectiveness of USAT versus CDT alone for ALI for our evaluated outcomes: amputation rate, major bleeding, clinical success, and adverse effects. Primary and secondary patency were not reported separately. There was no RCT evidence for PT. Limitations of this systematic review derive from the single included study, small sample size, short clinical follow-up period, and high risk of bias in critical domains. For this reason, the applicability of the results is limited. There is a need for high-quality studies to compare PT or USAT against open surgery, thrombolysis alone, no treatment, or other PT modalities for ALI. Future trials should assess outcomes, such as primary patency, amputation rate, major bleeding, clinical success, secondary patency, and adverse effects.