Arteriovenous Fistula

Researchers are evaluating a new 10-minute cardiovascular magnetic resonance (CMR) imaging protocol designed to improve current CMR procedures for patients with various heart conditions, including coronary artery disease, cardiomyopathies, and other cardiac diseases. The study aims to develop a standardized, contrast-free imaging method that can be applied to about 70% of cardiac patients. The goal is to assess whether this shorter protocol enhances diagnostic decision-making and reduces healthcare costs. The study involves two groups: healthy volunteers over 18 years old without significant cardiovascular or respiratory conditions, and patients over 18 years who require a clinically indicated CMR exam. The new protocol focuses on heart function and tissue characterization without using contrast agents. Researchers will compare the new 10-minute protocol to standard CMR imaging, evaluating its clinical feasibility, performance, and cost-effectiveness in different patient populations. Participants will undergo CMR scans using both the new and standard protocols. Researchers will monitor diagnostic results, scan completion rates, scan sequence times, adverse events, and cost differences between methods. Various heart tissue measurements and reproducibility between different readers and scanners will also be assessed. The study spans from 2019 to 2025, with ongoing safety monitoring during imaging sequences and a focus on improving the efficiency and quality of cardiac imaging.

Researchers are evaluating the safety and effectiveness of RLY-2608, a mutant-selective PI3Kα inhibitor, in adults and children with PIK3CA Related Overgrowth Spectrum (PROS) and malformations caused by PIK3CA mutations. This Phase 2 study has three parts: a dose selection phase, an exploratory phase with various participant groups, and a randomized, double-blind study comparing RLY-2608 to placebo. The study includes multiple subpopulations to understand how the drug works across ages and conditions related to PIK3CA mutations. Participants receive oral doses of RLY-2608 tailored for their age group. Children aged 2 to under 12 undergo dose escalation to find the appropriate dose, while those 12 years and older receive fixed doses. The study has single-arm dose expansion cohorts for different age groups, followed by a randomized phase where participants aged 6 and older receive either RLY-2608 or placebo. Dosing schedules and group assignments are carefully designed to assess safety and response in various participant groups. Throughout the study, participants undergo regular assessments including lesion volume measurements, safety labs, ECGs, and evaluations of side effects. Researchers collect samples to confirm PIK3CA mutation status and monitor plasma drug levels. Patient-reported outcomes and quality of life questionnaires are also used. The main outcomes include identifying the recommended dose, tracking adverse events, and measuring changes in lesion size and symptoms over time. Participation continues with regular monitoring until study completion or discontinuation, which may last several months or longer.

Researchers are evaluating non-invasive imaging methods to assess skin blood flow dynamics. This study aims to test and validate how well these imaging technologies perform by using a pressure cuff to create changes in blood flow, ranging from low flow (ischemic) to high flow (hyperemic). The focus is on establishing the basic feasibility of these imaging tools in detecting vascular changes. The study uses Multi-Spectral Imaging and Laser Speckle Imaging, both non-contact optical devices. Multi-Spectral Imaging measures concentrations of total, deoxygenated, and oxygenated hemoglobin in tissue, while Laser Speckle Imaging measures relative blood flow at different times. A pressure cuff occlusion is applied to stimulate changes in blood flow for these devices to detect. Participants will be observed using these imaging methods during vascular occlusion procedures. The main outcome measured is skin blood flow over a 4-week period. The study includes healthy volunteers aged 18 and older and involves non-invasive tests without treatment. Researchers will monitor blood flow changes and the performance of the imaging devices during the study period, which began in 2011 and is expected to continue until 2028.

Researchers are investigating targeted drug therapies for patients with vascular malformations that are resistant to standard treatments or for whom standard treatments are unsuitable. These vascular malformations are classified as either slow-flow or fast-flow types, driven by genetic changes in two specific signalling pathways. This phase II open-label trial aims to evaluate the effects of 48 weeks of treatment using either alpelisib for slow-flow vascular malformations with PI3K pathway mutations or mirdametinib for fast-flow vascular malformations with MAPK pathway mutations. Participants are divided into two treatment groups based on their vascular malformation type and genetic mutation. Those with slow-flow malformations and PI3K pathway mutations will receive alpelisib, an oral PI3-kinase inhibitor, for 48 weeks followed by a 24-week follow-up. Those with fast-flow malformations and MAPK pathway mutations will receive mirdametinib, an investigational oral MEK inhibitor, also for 48 weeks followed by 24 weeks of follow-up. Both treatments are given as monotherapy and involve genetic testing before enrollment to confirm mutations. Throughout the study, participants will undergo various assessments including symptom evaluations using the Vascular Malformation Patient Specific Outcome Measure (VM-PSOM) and OVAMA questionnaires, MRI scans to measure lesion size, and monitoring for adverse events. The primary outcome is the improvement in the most significant symptom after 48 weeks of treatment. Follow-up visits continue for 24 weeks after treatment ends to monitor ongoing effects and safety. The total participation duration for each patient is approximately 72 weeks.

This research focuses on patients with end-stage renal disease (ESRD), a condition affecting many people worldwide, especially as populations age and patients live longer on renal replacement therapy. Most patients with ESRD undergo hemodialysis (HD), which requires a reliable vascular access (VA) such as an arteriovenous fistula (AVF) or an arteriovenous graft (AVG). The study aims to evaluate the use of vascular access sound recordings and analysis to monitor VA function and predict complications like stenosis or failure, helping to improve patient outcomes. The study involves two groups of ESRD patients needing VA surgery for hemodialysis: one group receiving AVF creation, where a vein and artery are surgically connected in the forearm, and another receiving AVG creation, which uses an artificial plastic tube to connect an artery to a vein. This is a prospective observational study where VA sounds and Doppler ultrasound examinations will be collected over time to assess vascular remodeling and access function. Participants will have their vascular access sounds recorded and undergo ultrasound exams from day 7 after surgery up to 24 months. Researchers will monitor changes in sound characteristics and blood flow volume to evaluate VA maturation and function. The primary outcome measure is the low-high peak ratio (LHPR) of the sound, tracked over the study period. This approach aims to provide a non-invasive method to predict VA complications and improve management in ESRD patients on hemodialysis.

Researchers are evaluating the safety and effectiveness of everolimus monotherapy in adults with vascular malformations. This single-arm exploratory trial is conducted by Xuanwu Hospital, Capital Medical University, and includes adult patients aged 18 to 65 who have vascular malformations confirmed by MRI and are unsuitable for effective surgical treatment. Participants will take oral everolimus 10 mg daily in continuous 28-day treatment cycles. Treatment will continue until disease progression, intolerable side effects, lack of benefit as judged by the investigator, study end, or other criteria for stopping treatment. The study includes assessments at multiple points, including after 3, 6, and 12 treatment cycles, and every 6 cycles thereafter. During the study, participants will undergo MRI scans to measure lesion volume and assess microbleeding, iron deposits, and hemorrhage risk. Clinical signs, symptom scores, and quality of life will also be evaluated. These evaluations are scheduled during screening, after certain treatment cycles, and at the end of treatment. The main outcome measured is the response rate based on MRI after one year of treatment.

Researchers are evaluating the Lifetech Cera173 Vascular Plug System for patients who require arterial or venous embolization in the peripheral vasculature. This observational study aims to confirm the device's safety and performance, identify unknown side effects, monitor known side effects related to the device or procedure, and analyze emerging risks. The study plans to enroll 132 participants aged 18 to 85 years, with a life expectancy greater than one year. The study involves the use of the Cera173 Vascular Plug System, a self-expandable cylindrical Ni-Ti wire mesh device along with its accessory introducer kit. Participants will be those who need embolization treatment in peripheral arteries or veins, with target sites suitable for safe catheter insertion. This single-arm, open-label study will follow participants for one year after the procedure to monitor outcomes and safety. During the one-year follow-up, participants will undergo assessments to measure technical success at the time of the procedure and track secondary outcomes such as recanalization and migration of the device at 3, 6, and 12 months. Device- and procedure-related adverse events and serious adverse events will be monitored throughout the year. The study includes evaluations of device deficiencies and time to occlusion. Participants are expected to comply with all study visits and procedures to enable thorough safety and performance monitoring.

Researchers are conducting the Comprehensive HHT Outcomes Registry of the United States (CHORUS) to better understand Hereditary Hemorrhagic Telangiectasia (HHT), a rare genetic disorder causing abnormal blood vessels and related complications like bleeding, stroke, and heart failure. This observational study aims to collect long-term data on symptoms, complications, and the impact of HHT on patients' lives, helping improve knowledge and treatment options for the disease. Participants diagnosed with HHT through Curacao diagnostic criteria or genetic testing will be enrolled in this registry. The study will gather information retrospectively and prospectively over a 10-year period, collaborating with multiple HHT Centers of Excellence across the U.S. The registry will also serve as a centralized resource to help recruit participants for future clinical trials and research studies related to HHT. During the study, participants will provide permission to access their medical records and answer study-related questions by phone or clinic visits annually for up to 10 years. Researchers will collect data on demographics, diagnosis, family history, test results, treatments, symptoms, and complications. The main outcomes measured include baseline data and longitudinal clinical outcomes related to HHT, with additional assessments of severe morbidity, bleeding severity, vascular malformation growth, and treatment outcomes. Participants can withdraw at any time, and data confidentiality is prioritized.

Researchers are evaluating the effectiveness and safety of two types of balloon treatments—cutting balloons and drug-coated balloons—for venous stenosis in autologous arteriovenous fistulas used for hemodialysis. The study aims to determine whether drug-coated balloons offer better outcomes in terms of reducing the need for repeat procedures and to understand medical issues that may occur during treatment. The study will include 180 patients divided into two groups based on the treatment they receive: one group treated with cutting balloons and the other with drug-coated balloons. The treatments involve endovascular therapy, a minimally invasive procedure using catheters to access and treat the narrowed vein segments. The primary focus will be on patency rates and re-intervention rates at 1, 3, 6, and 12 months after the procedure, along with technical and procedural success and monitoring for major adverse events. Participants will be followed closely with evaluations at multiple time points to assess the condition of the treated arteries and veins. Researchers will track outcomes like the number of participants needing another procedure and how well the treated blood vessels remain open. The study will also monitor any complications during the perioperative period. The entire study will take place between June 2024 and December 2025, with follow-up assessments up to 12 months after treatment.

End-stage renal disease (ESRD) is a serious global health issue where patients often need hemodialysis using an arteriovenous fistula (AVF) for vascular access. AVFs are preferred due to longer use, fewer infections, and lower death rates compared to other options. However, many AVFs fail early because they do not mature properly, which happens in 20-40% of cases, making them unusable for dialysis. This research evaluates whether short-term use of apixaban, a blood thinner given during the critical 6-week maturation period after AVF creation, can improve fistula maturation rates without causing significant bleeding problems. The study compares two groups of adult ESRD patients undergoing primary upper arm AVF creation. One group receives apixaban 2.5 mg twice daily for 6 weeks starting after surgery, while the other group receives a matching placebo. Both groups receive standard intraoperative heparin during surgery but no study drug until 24 hours after surgery. Patients are followed for 6 months, with key assessments at 6 weeks, 3 months, and 6 months, including ultrasound measurements of vein size and blood flow, clinical exams, and recording dialysis use. Participants will undergo screening, surgery, and regular follow-up visits for clinical exams, ultrasound scans, lab tests, and monitoring for side effects like bleeding or hematoma. Researchers will measure fistula maturation based on size, blood flow, and usability for dialysis at 6 weeks, along with longer-term patency and complications. Compliance with study drug is checked by pill counts. Safety is overseen by a monitoring board, and data will be analyzed to see if apixaban improves AVF success compared to placebo.