Imaging of Arteriovenous Fistulas: From Maturation to Salvage-Podcast скачать в хорошем качестве

Imaging of Arteriovenous Fistulas: From Maturation to Salvage-Podcast

Imaging of Arteriovenous Fistulas: From Maturation to Salvage — A Practical, Imaging-Driven Guide for Hemodialysis Access Care Professional Summary This comprehensive RadioGraphics Fundamentals educational presentation provides an authoritative, practice-oriented review of the imaging evaluation and endovascular management of arteriovenous fistulas (AVFs) used for hemodialysis access. Developed by a multidisciplinary team from radiology, interventional radiology, and vascular surgery, the work synthesizes ultrasound (US), angiographic, and procedural insights to guide clinicians across the full AVF lifecycle—maturation, surveillance, maintenance, and declotting . Key Content Highlights 1. Hemodialysis Access Fundamentals AVFs are emphasized as the preferred long-term dialysis access due to lower infection, thrombosis, and mortality rates compared with grafts and catheters. The presentation contextualizes access choice within patient anatomy, comorbidities, life expectancy, and timing of dialysis initiation. 2. Ultrasound Evaluation and Fistula Maturation Detailed protocols for gray-scale, color Doppler, spectral Doppler, and power Doppler US are provided. The Rules of Six are clearly illustrated, including vessel diameter, depth, flow volume (≥500–600 mL/min), and usable length. Common pitfalls—such as turbulent flow measurements, improper Doppler angle, and overlooked accessory veins—are highlighted with corrective strategies. 3. Mechanisms of Failure to Mature Failure rates of up to 70% in radiocephalic fistulas are discussed. Causes are systematically categorized into: Inflow problems (arterial disease, anastomotic or juxta-anastomotic stenosis) Outflow problems (peripheral venous stenosis, accessory or collateral veins) The hemodynamic impact of converting a serial to a parallel outflow circuit is clearly explained. 4. Characteristic Stenosis Patterns Each fistula type is linked to predictable stenotic sites: 1. Radiocephalic AVF → juxta-anastomotic stenosis 2. Brachiocephalic AVF → cephalic arch stenosis 3. Brachial vein transposition (BVT) → swing-point stenosis These patterns are reinforced with schematic illustrations and imaging-pathologic correlation. 5. Endovascular Treatment Strategies Percutaneous transluminal angioplasty (PTA) is presented as first-line therapy, with guidance on balloon sizing and high-pressure techniques. Drug-coated balloons are critically reviewed, with randomized trial and meta-analysis data showing improved target lesion patency in selected scenarios. Covered stents are favored over bare metal stents for recurrent or resistant stenoses, pseudoaneurysms, and select complications. Clear recommendations are provided on when not to stent, preserving future access options. 6. Declotting Techniques Step-by-step declot workflows are outlined, including: 1. Pharmacologic thrombolysis (tPA) 2. Balloon maceration 3. Fogarty catheter sweeps 4. Mechanical thrombectomy Transjugular (IJ) access is highlighted as an efficient, ergonomic, and versatile approach for complex declots. The importance of intervention within 24 hours to maximize fistula salvage is emphasized. 7. Complication Recognition and Management Major and minor complications are reviewed, including extravasation, venous rupture, stent fracture, pseudoaneurysm formation, and arterial embolization. Imaging-guided management algorithms are provided to ensure timely recognition and intervention. Key Takeaways 1. Imaging is central to every phase of AVF care—from creation and maturation to salvage. 2. Mastery of duplex ultrasound interpretation and recognition of characteristic stenosis patterns enables earlier, more effective intervention. 3. Tailored endovascular strategies, informed by anatomy and evidence, are essential to prolong access longevity. 4. Rapid response to thrombosis and structured follow-up are critical to preserving dialysis access in this high-risk population. APA 7th Edition Citation Sailer, A., Dixe de Oliveira Santo, I., Revzin, M. V., Chan, S. M., Borse, R. M., Cornman-Homonoff, J., Cardella, J., Perez Lozada, J. C., & Marino, A. G. (2025). Imaging of arteriovenous fistulas: Maturation, maintenance, and declotting. RadioGraphics Fundamentals. Radiological Society of North America. Hashtags (Professional / Academic Reach) #Radiology #InterventionalRadiology #HemodialysisAccess #ArteriovenousFistula #VascularImaging #Ultrasound #RadioGraphics #RSNA #EndStageRenalDisease #DialysisCare #EvidenceBasedMedicine #Dialysis #KidneyDisease #Hemodialysis #MedicalEducation #Healthcare #Nephrology #AVFistula #VascularAccess #InterventionalRadiology #DialysisLife #FistulaCare #MedEd #Angioplasty #FistulaMaturation #KidneyFailure #VascularSurgery © 2025 AI Chavelle™ by Jeffrey Chen / SmartRad AI. All rights reserved.