Ultrasound-guided femoral approach for coronary angiography and interventions in the porcine model.

Coronary angiography and percutaneous coronary intervention (PCI) procedural details in swine are similar to those performed to humans, since their heart and coronary anatomy closely resembles. However, only a few detailed descriptions of the procedure are available, containing notable differences. We present a feasible and reproducible protocol for percutaneous coronary interventions in porcine experimental models, utilizing ultrasound-guided femoral approach. Nine female pigs were studied to explore the feasibility of superficial femoral arterial (SFA) access for coronary angiography and provisional PCI, as well as the most suitable guiding coronary catheters and angiographic projections for the above interventions. Experiments were performed under general anesthesia, using ultrasound-guided puncture of the SFA to gain arterial access. The Amplatzer AR1® catheter, and the Right Coronary Bypass® catheter were used for the selective engagement of the right and the left coronary artery, respectively. Successful arterial access and subsequent cardiac catheterization were performed in all pigs. Only one animal required a second puncture for femoral artery access. None of the 9 animals presented any significant tachycardia or hypotensive episode. One animal developed an access site-related complication following the first catheterization procedure. During follow-up, 100% success of SFA catheterization was achieved using the same ultrasound-guided technique. The ultrasound-guided superficial femoral artery access for coronary angiography and provisional interventions in porcine models is a quick and safe alternative to the carotid artery approach. The RCB and AR1 catheters may be the best choice for the quick and easy selective coronary engagement of the right and left ostia, respectively.

Histopathological evaluation of a retinoic acid eluting stent in a rabbit iliac artery model.

This study aimed to evaluate the safety and efficacy of innovative retinoic acid (RA) eluting stents with bioabsorbable polymer. Sixty stents divided in ten groups were implanted in the iliac arteries of 30 rabbits. Two polymers ("A", poly (lactic-co-glycolic acid) and "B", polylactic acid), and three doses ("Low", "Medium" and "High") of RA (groups: AL, AM, AH, BL, BM, BH) were used on cobalt chromium stents (Rontis Corporation), one group of bare stent (C), one group (D) of Everolimus eluting stent (Xience-Pro, Abbot Vascular), and two groups of Rontis Everolimus eluting stents coated with polymer A (EA) and B (EB). Treated arteries were explanted after 4 weeks, processed by methyl methacrylate resin and evaluated by histopathology. None of the implanted stents was related with thrombus formation or extensive inflammation. Image analysis showed limited differences between groups regarding area stenosis (BH, D and EB groups had the lower values). Group BH had lower intimal mean thickness than AH (105.1 vs 75.3 µm, p = 0.024). Stents eluting RA, a non-cytotoxic drug, were not related with thrombus formation and had an acceptable degree of stenosis 4 weeks post implantation. RA dose and type of polymer may play role in the biocompatibility of the stents.

Percutaneous Arteriovenous Fistula Creation with the WavelinQ 4-French EndoAVF System: A Single-Center Retrospective Analysis of 30 Patients.

PURPOSE: To retrospectively assess the safety and efficacy of percutaneous arteriovenous fistula (pAVF) creation with the WavelinQ 4-F EndoAVF System. MATERIALS AND METHODS: From February 2018 to June 2020, 30 pAVFs were created in 30 consecutive patients (men; age, 55.3 years ± 13.6). Of the 30 patients, 21 (70%) were already on hemodialysis using a central venous catheter. The primary outcome measures were technical success, complications, and cannulation rate. The secondary outcome measures included the number of secondary procedures needed for cannulation, maintenance time to cannulation, and pAVF survival. RESULTS: Technical success was 100%. The adverse event rate was 6.7% (2/30), including a pseudoaneurysm of the brachial artery that developed immediately after sheath removal and an aneurysm of the anastomosis 17 days after the procedure, which was treated with a covered stent placed in the arterial side. The mean follow-up was 547 days ± 315.7 (range, 14-1,071 days). The cannulation rate was 86.7% (26/30). The mean time to cannulation was 61.3 days ± 32.5 (range, 15-135 days). The mean follow-up after cannulation was 566.2 days ± 252.7 (range, 35-1,041 days). Four pAVFs were thrombosed after cannulation, with 2 of them successfully declotted. Sixteen interventions were needed to achieve cannulation after the index procedure in 15 patients (overall, 0.53 procedures/patient). Seven maintenance endovascular interventions (following cannulation) were performed during the follow-up period in 6 patients (overall, 0.27 procedures/patient, 0.17 procedures/patient-years). For the pAVFs that were cannulated, patency was 96% at 1 year, and 82% at 2 and 3 years, according to the Kaplan-Meier survival analysis. CONCLUSIONS: This initial experience suggests that pAVF creation is safe and can be successfully performed with high maturation and long-term patency rates. Larger-scale prospective studies are needed to validate the 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.

Two-Center Prospective Comparison of the Trocar and Seldinger Techniques for Percutaneous Cholecystostomy.

OBJECTIVE. The purpose of this study is to compare the safety and efficacy of the bedside ultrasound (US)-guided trocar technique versus the US- and fluoroscopy-guided Seldinger technique for percutaneous cholecystostomy (PC). SUBJECTS AND METHODS. This prospective noninferiority study compared the bedside US-guided trocar technique for PC (the trocar group; 53 patients [28 men and 25 women]; mean [± SD] age, 74.31 ± 16.19 years) with the US- and fluoroscopy-guided Seldinger technique for PC (the Seldinger group; 52 patients [26 men and 26 women], mean age, 79.92 ± 13.38 years) in consecutive patients undergoing PC at two large tertiary university hospitals. The primary endpoints were technical success and procedure-related complication rates. Secondary endpoints included procedural duration, pain assessment, and clinical success after up to 3 months of follow-up. RESULTS. PC was successfully performed for all 105 patients. The clinical success rate was similar between the two study groups (86.8% in the trocar group vs 76.9% in the Seldinger group; p = 0.09). Mean procedural time was significantly lower in the trocar group than in the Seldinger group (1.77 ± 1.62 vs 4.88 ± 2.68 min; p < 0.0001). Significantly more procedure-related complications were noted in the Seldinger group than in the trocar group (11.5% vs 1.9%; p = 0.02). Among patients in the Seldinger group, bile leak occurred in 7.7%, abscess formation in 1.9%, and gallbladder rupture in 1.9%. No procedure-related death was noted. Minor bleeding occurred in one patient (1.9%) in the trocar group, but the bleeding resolved on its own. The mean pain score during the procedure was significantly lower in the Seldinger group than in the trocar group (3.2 ± 1.77 vs 4.76 ± 2.17; p = 0.01). At 12 hours after the procedure, the mean pain score was significantly lower for patients in the trocar group (0.78 ± 1.0 vs 3.12 ± 1.36; p = 0.0001). CONCLUSION. Use of the bedside US-guided trocar technique for PC was equally effective as the Seldinger technique but was associated with fewer procedure-related complications, required less procedural time, and resulted in decreased postprocedural pain, compared with fluoroscopically guided PC using the Seldinger technique.

Use of Drug-Coated Balloons in Dysfunctional Arteriovenous Dialysis Access Treatment: The Effect of Consecutive Treatments on Lesion Patency.

PURPOSE: A retrospective longitudinal analysis was performed to evaluate the outcome of consecutive treatments with drug-coated balloons (DCBs) in dysfunctional arteriovenous (AV) dialysis access (fistulae and grafts). MATERIALS AND METHODS: From January 2015 to December 2017, 339 DCBs were used in 257 procedures in 165 patients with dysfunctional accesses. Of these, 38 patients had ≥ 2 procedures and were included in the analysis. A total of 112 procedures were performed with 133 devices (22 patients treated twice, 4 treated 3 times, 7 treated 4 times, 2 treated 5 times, and 3 treated 6 times). Mean balloon diameter was 8.13 mm (min-max range, 3-12 mm) and length was 63.16 mm (min-max range, 40-150 mm). Primary outcome measures were safety and effectiveness based on the noninferiority hypothesis that the second treatment would be as effective as the first regarding postintervention primary patency (PIPP). Secondary outcome measures included independent factors that may influence outcomes. RESULTS: Mean lesion follow-up was 617 d (range, 175-1,100 d). Median PIPP durations were 216.5 d for the first intervention and 280 d for the second (P = .37; hazard ratio, 1.271; 95% confidence interval, 0.75-2.16). There was a significant difference in PIPP in favor of the second intervention when patients with only 2 interventions (22 of 38; 57.9%) were included (first intervention, 269 d; second intervention, 520 d; P = .03; hazard ratio, 2.354; 95% confidence interval, 1.087-5.098). CONCLUSIONS: There was no significant difference in PIPP between the first and second DCB procedures. Results suggest consistency in PIPP with the use of DCBs regardless of aging AV access.