Evaluation of a new paclitaxel-coated balloon catheter in an in vivo porcine peripheral venous model: Feasibility, safety, and drug deliverability

PURPOSE

To evaluate in vivo the feasibility, safety, and paclitaxel (PTX) deliverability of a newly developed non-commercially available Paclitaxel-Coated Balloon (PCB) catheter in the swine healthy peripheral vein model.

MATERIALS AND METHODS

In total 12 PCBs were deployed in 12 venous segments. Primary feasibility endpoint was the successful application of the devices to the veins of the animals. Primary efficacy endpoint was the determination of the drug content in the venous tissue at 24 h and 7 days after balloon expansion, as assessed by analysis of the vein tissue with High Performance Liquid Chromatography (HPLC) coupled with tandem mass spectrometry. Primary safety endpoint was freedom from any major adverse event. Secondary endpoint was the investigation of any independent factor affecting the primary endpoints.

RESULTS

Paclitaxel was detected in five out of six tissue samples 24 h post-intervention and five out of six tissues at 7 days following the procedure (10 tissue samples out of 12). The mean weight of tissue that was examined was 0.20604 ± 0.29822 g (range: 1.02823-0.03377 g) and the mean PTX concentration detected was 8.4 ± 13.1 μg/g (range: 0-36.1 μg/g). The average drug content detected at 24 h (17.1 ± 17.1 μg/g) was numerically superior, but non-statistically significant, compared to 7 days (3.1 ± 3.6 μg/g). An average of 33.8% of the drug remained on the balloon after retrieval. According to the multiple linear regression analysis, there was no significant correlation between transition time, PTX remaining on the balloon, time of analysis (24 h/7 days) and PTX tissue concentration. No abnormalities were noted during autopsy.

CONCLUSION

The newly developed PCB successfully delivered within the healthy venous wall a dose of Paclitaxel that inhibits neointimal hyperplasia. No safety issues were raised at short-term follow-up.

Long-term outcomes of paclitaxel-coated balloons for non-malignant ureteral strictures

PURPOSE

To evaluate the clinical efficacy and safety of drug-coated balloon (DCB) ureteroplasty for the management of non-malignant ureteral strictures.

MATERIAL AND METHODS

A prospective "off-label" monocentric single-arm pilot study investigating the safety and efficacy of drug-coated balloon (DCB) (Lutonix^®; BD, USA) was performed. Twenty-five patients with benign ureteral strictures related to uretero-enteric anastomosis (n = 13); lithiasis (n = 5), post-surgical complications (iatrogenic n = 5), transplanted kidney (n = 1) and post-radiotherapy (n = 1) were included. Following lesion crossing, predilatation was performed using 4-7 mm high-pressure balloon catheter (5-6Fr) with a balloon pressure of 6-7 atm based on the manufacturer's recommendation. In the absence of rupture of the ureteral wall, the DCB was dilated for 4 min. across the lesion. The process was repeated if deemed necessary to a maximum of three stricture dilatations. We analysed both clinical and radiological primary patency (no signs of ipsilateral hydronephrosis or improvement of the existing residual dilatation at the follow-up examinations) and secondarily safety endpoints.

RESULTS

Mean lesion length was 40 ± 28.5 mm. Mean time follow up was 36 months ± 10.46 months. Strictures were located at upper ureteric (12%), lower ureteric (32%), ureterovesical anastomosis (4%) and uretero-enteric anastomosis (52%) levels. The overall radiological success at 1-year follow-up was 88% (22/25 patients). In 56% patients (14/25 patients with primary patency) the nephrostomy catheter was removed 21 days following a single DCB procedure. In 32% (8/25 patients) an additional dilatation sessions were required for maintaining the ureteral patency. The overall failure rate at 1-year follow-up was 12% (3/25 patients). Only one case of febrile urinary tract infection in a female patient (acute pyelonephritis) was encountered after the first dilatation.

CONCLUSIONS

Paclitaxel-coated balloon ureteroplasty proved to be safe and effective for the treatment of non-malignant ureteral strictures. Larger studies are warranted to validate these promising initial results.

Use of the Covera Stent Graft for the Treatment of Dysfunctional or Thrombosed Arteriovenous Grafts: A Retrospective Analysis of 64 Patients

PURPOSE

To retrospectively evaluate the safety and effectiveness of the Covera stent graft (SG) for the treatment of dysfunctional or thrombosed arteriovenous grafts (AVGs).

MATERIALS AND METHODS

Within 29 months (February 2016-August 2018), 79 patients underwent Covera SG placement in the authors' department for the treatment of dysfunctional AVGs. Data were available for 64 patients who underwent 64 procedures, using 64 devices. Minimum follow-up was 6 months, unless reintervention occurred. Mean follow-up was 277 days (6-923 days). Treatment characteristics were 51 cases with venous-graft anastomosis (VGA) stenosis (79.7%), 13 cases of puncture zone stenosis (20.3%), 14 cases of in SG stenosis (21.9%), 8 cases of pseudoaneurysm treatment (12.5%) (1 treatment area might have had more than 1 characteristic). Thirty-six patients presented with thrombosis (56.2%), and 31 of 64 case were de novo treatment areas (48.4%). Primary outcome measurements were technical success and post-intervention primary patency (PIPP) at 6 months, whereas secondary outcome measurements included factors influencing primary outcome.

RESULTS

Technical success was 100%. Median PIPP was 336 days, and 73.6% of treatment areas were patent at 6 months. There were no significant differences in terms of PIPP when de novo treatment areas were compared with restenotic areas (519 vs. 320 days, respectively; P = .1); patients who presented with versus those who presented without thrombosis (320 vs. 583 days, respectively; P = .07); puncture zone stenosis or elsewhere (329 vs. 686 days, respectively; P = .52); and VGA stenosis or elsewhere (336 vs. 335 days, respectively; P = .9).

CONCLUSIONS

Use of the Covera SG for AVG treatment was safe and effective in every type of treatment area presented in this retrospective analysis.

Incidence and Endovascular Treatment of Isolated Atherosclerotic Popliteal Artery Disease: Outcomes from the IPAD Multicenter Study

PURPOSE

To report the incidence and long-term outcomes following endovascular treatment of symptomatic, atherosclerotic isolated popliteal artery disease (IPAD).

MATERIALS AND METHODS

This retrospective, multicenter study included all patients who underwent endovascular treatment of IPAD between January 2010 and December 2016 because of intermittent claudication or critical limb ischemia (CLI), in three tertiary University Hospitals. In total, 4717 peripheral arterial disease (PAD) procedures were analyzed. The study's primary outcome measures were: IPAD incidence, binary restenosis rate and freedom from target lesion revascularization (TLR). Secondary outcome measures included technical success, limb salvage rate and the identification of predictors of outcomes.

RESULTS

The incidence of IPAD was 0.98% (46/4717 PAD procedures). In total, 46 patients (38 male; mean age 73 ± 12 years) underwent plain balloon (69.5%) or bail-out stenting (30.5%) procedures. Most patients suffered from CLI (65.2%). Mean lesion length was 52.5 ± 32.0 mm and 45.6% of the cases were occlusions. Severe calcifications were noted in 26.1%. Technical success was 100%. Mean time follow-up was 32.6 ± 25.6 months. According to Kaplan-Meier analysis, restenosis was 15.8, 40.9, 45.8% and TLR-free rate was 90.5, 79.0, 74.1%, at 1, 2 and 3 years, respectively. Survival and limb salvage rates were 73.6 and 88.1%, at 5 years, respectively. The major amputation rate for CLI patients was 10.0% (3/29 limbs), while no major amputations occurred in the claudication subgroup. Cox multivariable analysis detected baseline occlusion as an independent predictor of increased restenosis (HR 5.3; 95% CI 0.21-0.66, p = 0.02).

CONCLUSIONS

Isolated popliteal lesions requiring treatment appear in nearly 1% of patients with PAD. Balloon angioplasty and bail-out stenting resulted in acceptable long-term clinical outcomes. Treatment of occlusions was correlated with increased restenosis rate.

A survival guide for endovascular declotting in dialysis access: procedures, devices, and a statistical analysis of 3,000 cases

INTRODUCTION

Thrombosis is the most important access-related complication. Several declotting procedures have been suggested falling mainly into two categories; thrombolysis-dependent and thrombectomy-dependent.

AREAS COVERED

Seventeen studies after 2001 have been published on percutaneous treatment of thrombosed vascular access. Authors performed a systematic review of these studies together with a parametric meta-analysis of data available investigating clinical success, postintervention assisted primary patency (PAPP) and independent factors that could influence outcome measures.

EXPERT COMMENTARY

A shift to thrombectomy-dependent procedures is observed with a view to diminishing complications from the use of thrombolytic agents. Arteriovenous fistulas provide significantly better PAPP, while newer studies show improved, non-significant results compared with older ones. The role of improvement of devices for subsequent angioplasty is of equal importance, if not more, for improved declotting results.

Lysis-Assisted Balloon (LAB) Thrombectomy. A Declotting Technique for the Treatment of Thrombosed Arteriovenous Dialysis Grafts. 5-Year Experience of 241 Endovascular Procedures

BACKGROUND

This is a retrospective single-center analysis investigating the results of a percutaneous lysis-assisted balloon (LAB) thrombectomy procedure for the treatment of thrombosed arteriovenous dialysis grafts (AVGs).

MATERIALS AND METHODS

Within 5 years (January 2012-December 2016), 291 declotting procedures were performed for the treatment of thrombosed dialysis arteriovenous fistulas or grafts. Data were available for 129 patients (75 men, 58.1%) with an AVG, undergoing 241 procedures [1.87 procedures/patient (1-10)]. Procedure includes initial lysis with 5 mg recombinant tissue plasminogen activator followed by thrombectomy with a high-pressure balloon for thrombus maceration using "facing sheaths" technique. 61 patients had ≥ 2 declotting procedures. In 80 cases (80/241; 33.2%), a stent graft (SG) was used for treatment of persistent stenosis. Main primary outcome measures were clinical success and postintervention assisted primary patency (PAPP). Secondary outcome measures included procedural complications and investigation of independent factors that could influence circuit survival.

RESULTS

Median PAPP was 434 days according to Kaplan-Meier survival analysis. Clinical success was 96.26%. In six cases (6/241, 2.49%) declotting failed and a catheter was placed. There were 16 minor (16/241, 6.64%) and no major complications. There was no significant difference in circuit survival regardless of SG use (No SG 406 days vs. SG 349 days; p = 0.24). There was a significant difference in favor of the second declotting compared to the first in 61 patients (first: 162 days vs. second: 447 days; p < 0.0001).

CONCLUSION

LAB thrombectomy resulted in high-circuit survival rates with increased technical success and minimum complications without the use of thrombectomy devices.

Paclitaxel-Coated Balloons for the Treatment of Symptomatic Central Venous Stenosis in Dialysis Access: Results from a Randomized Controlled Trial

PURPOSE

To compare the clinically-assessed intervention-free period (IFP) of paclitaxel-coated balloon (PCB) vs conventional balloon angioplasty (CBA) for the treatment of symptomatic central venous stenosis (CVS) in dialysis access.

MATERIALS AND METHODS

Within 20 months, 40 dialysis patients (19/40 arteriovenous fistulae [AVFs] and 21/40 arteriovenous grafts [AVGs]) were randomized to undergo angioplasty either with a PCB (PCB group, n = 20; 14/20 male; age: 56.7) or CBA (CBA group, n = 20; 15/20 male; age: 57). There were 15/20 restenotic lesions in PCB group and 12/20 in CBA group. In 25/40 cases, patients had an ipslateral catheter insertion in the past. Primary endpoint was clinically-assessed intervention-free period (IFP) of the treated segment at 6 months, while secondary endpoints included complication rates during follow-up period and identification of factors influencing IFP.

RESULTS

Median IFP was significantly better in PCB group (PCB group: 179 days, vs CBA group: 124.5 days, P = .026). Mean follow-up period was 180 days (range, 5-479). There was no significant difference between AVGs and AVFs (P = .17), treatment of de novo vs restenotic lesions (P = .33), or prior presence of catheter insertion (P = .21). No complications were observed. In restenotic lesions in PCB group, longitudinal comparison between treatments also showed a significant difference in favor of PCB treatment (median IFP in PCB* group 177 vs 91 days in CBA* group; P = .01).

CONCLUSIONS

In this prospective study, PCB had significantly better results compared with CBA for the treatment of symptomatic central venous stenosis in dialysis access. Retrospective longitudinal comparison of treatments in the same patients also showed a significant difference in favor of PCBs.

Paclitaxel-Coated Balloons for the Treatment of Dysfunctional Dialysis Access. Results from a Single-Center, Retrospective Analysis

PURPOSE

To investigate the safety and effectiveness of lutonix paclitaxel-coated balloon (PCB) for the treatment of dysfunctional dialysis access.

MATERIALS AND METHODS

This was a single-center, single-arm, retrospective analysis of 39 patients (23 male, 59 %) undergoing 61 interventions using 69 PCBs in a 20-month period. There was a balance between arteriovenous fistulae (AVF) and grafts (AVG) (20 AVFs, 19AVGs), and the majority of lesions were restenotic (25/39, 64.1 %). Mean balloon diameter used was 6.6 mm and length 73.4 mm. Primary outcome measure was target lesion primary patency (TLPP) at 6 months, while secondary outcome measures included factors affecting TLPP and major complications. As there were lesions treated more than once with PCB, authors also compared patency results after first and second PCB angioplasty.

RESULTS

TLPP was 72.2 % at 6 months with a median patency of 260 days according to the Kaplan-Meier survival analysis. No major complications occurred. TLPP between AVFs and AVGs (311 vs. 237 days, respectively; p = 0.29) and de novo and restenotic lesions was similar (270.5 vs. 267.5 days, respectively; p = 0.50). In 14 cases, in which lesions were treated with two PCB angioplasties, a statistically significant difference in TLPP after the second treatment was noted (first intervention 179.5 days vs. second intervention 273.5 days; p = 0.032).

CONCLUSION

In this retrospective analysis, Lutonix PCB proved to be safe and effective in treating restenosis in dysfunctional dialysis access with results comparable to the literature available. Larger studies are needed to prove abovementioned results.