Repeat BTK revascularization: when, how and what are the results?

Outcomes and Patency of Endovascular Infrapopliteal Reinterventions in Patients With Chronic Limb-Threatening Ischemia

PURPOSE

Endovascular revascularization is the preferred treatment to improve perfusion of the lower extremity in patients with chronic limb-threatening ischemia (CLTI). Patients with CLTI often present with stenotic-occlusive lesions involving the infrapopliteal arteries. Although the frequency of treating infrapopliteal lesions is increasing, the reintervention rates remain high. This study aimed to determine the outcomes and patency of infrapopliteal endovascular reinterventions.

METHODS

This retrospective, multicenter cohort study of 3 Dutch hospitals included patients who underwent an endovascular infrapopliteal reintervention in 2015 up to 2021 after a primary infrapopliteal intervention for CLTI. The outcome measures after the reintervention procedures included technical success rate, the mortality rate and complication rate (any deviation from the normal postinterventional course) at 30 days, overall survival, amputation-free survival (AFS), freedom from major amputation, major adverse limb event (MALE), and recurrent reinterventions (a reintervention following the infrapopliteal reintervention). Cox proportional hazard models were used to determine risk factors for AFS and freedom from major amputation or recurrent reintervention.

RESULTS

Eighty-one patients with CLTI were included. A total of 87 limbs underwent an infrapopliteal reintervention in which 122 lesions were treated. Technical success was achieved in 99 lesions (81%). The 30-day mortality rate was 1%, and the complication rate was 13%. Overall survival and AFS at 1 year were 69% (95% confidence interval [CI], 55%-79%) and 54% (95% CI, 37%-67%), respectively, and those at 2.5 years were 45% (95% CI, 33%-56%) and 21% (95% CI, 11%-33%), respectively. Freedom from major amputation, MALE, and recurrent reinterventions at 1 year and 2.5 years were 59% (95% CI, 46%-70%) and 41% (95% CI, 25%-56%); 54% (95% CI, 41%-65%) and 36% (95% CI, 21%-51%); and 68% (95% CI, 55%-78%) and 51% (95% CI, 33%-66%), respectively. A Global Limb Anatomic Staging System score of III showed an increased hazard ratio of 2.559 (95% CI, 1.078-6.072; p=0.033) for freedom of major amputation or recurrent reintervention.

CONCLUSIONS

The results of this study indicate that endovascular infrapopliteal reinterventions can be performed with acceptable 30-day mortality and complication rates. However, outcomes and patency were moderate to poor, with low AFS, high rates of major amputations, and recurrent reinterventions.

CLINICAL IMPACT

This multicenter retrospective study evaluating outcome and patency of endovascular infrapopliteal reinterventions for CLTI, shows that endovascular infrapopliteal reinterventions can be performed with acceptable 30-day mortality and complication rates. However, the short- and mid-term outcomes of the infrapopliteal reinterventions were moderate to poor, with low rates of AFS and a high need for recurrent reinterventions. While the frequency of performing infrapopliteal reinterventions is increasing with additional growing complexity of the disease, alternative treatment options such as venous bypass grafting or deep venous arterialization may be considered and should be studied in randomized controlled trials.

Effect of Recombinant Netrin-1 Protein Combined with Peripheral Blood Mesenchymal Stem Cells on Angiogenesis in Rats with Arteriosclerosis Obliterans

This work was aimed to explore the effect of recombinant netrin-1 protein and peripheral blood mesenchymal stem cells (MSCs) on the angiogenesis ability of atherosclerosis. 28 Sprague Dawley (SD) rats were taken as research models. The arterial occlusion models were created by surgery and then divided into the saline control group (n =7), netrin-1 treatment group (n =7), MSCs treatment group (n =7), and netrin-1 + MSCs combined treatment group (n =7). The peripheral blood MSCs were extracted from the peritoneal cavity of diseased SD rats and cultured alone or in combination with netrin-1. The individually cultured MSCs and netrin-1 were locally injected into the ischemic tissues of SD rats. The Tarlov scoring was performed at the first, second, and third week of treatment, respectively. The expression of vascular endothelial growth factor (VEGF) was also measured by quantitative real-time polymerase chain reaction (qRT-PCR), and the capillary density was measured by immunofluorescence staining. The mean maximum contractility of the gastrocnemius muscle in each group was determined in the third week after treatment. The Tarlov score of the netrin-1 + MSCs group was significantly higher than that of the control group (P < 0.05) at the second week. To the 4th week of treatment, the Tarlov score of the netrin-1 + MSCs group was highly increased compared to the netrin-1 group and the MSCs group (P < 0.05). The expression of VEGF in the treatment groups was greatly increased each week compared to the control group (P < 0.05). Compared with the netrin-1 and the MSCs groups, the VEGF was also notably increased in the netrin-1 + MSCs group (P <0.05). The capillary densities of the treatment groups were observably greater than that of the control group in the second and third weeks (P <0.05), while the capillary density in the netrin-1 + MSCs group was also significantly increased than those in the netrin-1 group and the MSCs group (P < 0.05). The mean maximum contractility of the netrin-1 + MSCs group was remarkably higher than that of the other groups (P < 0.05). The netrin-1 + MSCs group achieved the higher Tarlov score, higher VEGF expression, higher capillary density, and better muscle recovery than netrin-1 and MSCs treatments.

The role of atherectomy in BTK lesions. A systematic review

INTRODUCTION

To evaluate the current role of atherectomy techniques (ATH) in treatment of peripheral arterial disease (PAD) at below the knee (BTK) arteries.

EVIDENCE ACQUISITION

The PubMed and Embase were searched (last search on 11 September 2021) for studies reporting on the early and mid-term outcomes of ATH in BTK vessels. Analysis included the data from six studies, with a total of 1062 PAD patients treated with various ATH techniques. We compared them the ATH outcomes with the contemporaneous outcomes of plain balloon angioplasty alone or with bailout stenting. Early safety and efficacy were accessed with perioperative and 30-day technical success rate, which included the primary patency of the treated BTK arterial segment. Evaluation of clinical performance was based on target limb revascularization (TLR) and on major limb adverse events (MALEs) rates.

EVIDENCE SYNTHESIS

The current body of literature mainly includes retrospective observational studies, and the level of derived evidence is low. The mean perioperative and 30-day technical success rate was 87.3%. The mean reported TLR and MALEs rates at 12 months were 6.6% and 4.7% respectively. The relevant rates in studies reporting at 24 months were 24.3% and 31.7% while in studies reporting at 36 months the rates were 37.0% and 23.0% respectively.

CONCLUSIONS

Based in low-quality evidence, it seems that ATH in BTK vessels has a high safety, high efficacy profile and durable outcomes at 12 months. In the midterm, the clinical success of ATH is compromised by increased TLR and MALEs rates. Comparison of ATH with other endovascular techniques in BTK treatment of PAD shows a slight lead of ATH at 1-year and equivalent clinical performance in the mid-term. Overall, ATH has a significant and potentially predominant role in treatment of BTK vessels.