Study protocol of a prospective single-arm multicenter clinical study to assess the safety and performance of the aXess hemodialysis graft: The pivotal study.

BACKGROUND: Arteriovenous grafts (AVGs) are used for patients deemed unsuitable for the creation of an autogenous arteriovenous fistula (AVF) or unable to await maturation of the AVF before starting hemodialysis. However, AVGs are prone to infection and thrombosis resulting in low long-term patency rates. The novel aXess Hemodialysis Graft consists of porous polymeric biomaterial allowing the infiltration by cells and the growth of neotissue, while the graft itself is gradually absorbed, ultimately resulting in a fully functional natural blood vessel. The Pivotal Study will examine the long-term effectiveness and safety of the aXess Hemodialysis Graft. METHODS: The Pivotal Study is a prospective, single-arm, multicenter study that will be conducted in 110 subjects with end-stage renal disease who are not deemed suitable for the creation of an autogenous vascular access. The primary efficacy endpoint will be the primary patency rate at 6 months. The primary safety endpoint will be the freedom from device-related serious adverse events at 6 months. The secondary endpoints will include the procedural success rate, time to first cannulation, patency rates, the rate of access-related interventions to maintain patency, the freedom from device-related serious adverse events and the rate of access site infections. Patients will be followed for 60 months. An exploratory Health Economic and Outcomes Research sub-study will determine potential additional benefits of the aXess graft to patients, health care institutions, and reimbursement programs. DISCUSSION: The Pivotal study will examine the long-term performance and safety of the aXess Hemodialysis Graft and compare the outcome measures with historical data obtained with other graft types and autogenous AVFs. Potential advantages may include superior long-term patency rates and lower infection rates versus currently available AVGs and a shorter time to first cannulation compared to an autologous AVF. As such, the aXess Hemodialysis Graft may fulfill an unmet clinical need in the field of hemodialysis access.

Six-year outcomes of a phase II study of human-tissue engineered blood vessels for peripheral arterial bypass.

Objective: The human acellular vessel (HAV) was evaluated for surgical bypass in a phase II study. The primary results at 24 months after implantation have been reported, and the patients will be evaluated for ≤10 years. Methods: In the present report, we have described the 6-year results of a prospective, open-label, single-treatment arm, multicenter study. Patients with advanced peripheral artery disease (PAD) requiring above-the-knee femoropopliteal bypass surgery without available autologous graft options had undergone implantation with the HAV, a bioengineered human tissue replacement blood vessel. The patients who completed the 24-month primary portion of the study will be evaluated for ≤10 years after implantation. The present mid-term analysis was performed at the 6-year milestone (72 months) for patients followed up for 24 to 72 months. Results: HAVs were implanted in 20 patients at three sites in Poland. Seven patients had discontinued the study before completing the 2-year portion of the study: four after graft occlusion had occurred and three who had died of causes deemed unrelated to the conduit, with the HAV reported as functional at their last visit. The primary results at 24 months showed primary, primary assisted, and secondary patency rates of 58%, 58%, and 74%, respectively. One vessel had developed a pseudoaneurysm deemed possibly iatrogenic; no other signs of structural failure were reported. No rejections or infections of the HAV occurred, and no patient had required amputation of the implanted limb. Of the 20 patients, 13 had completed the primary portion of the study; however, 1 patient had died shortly after 24 months. Of the remaining 12 patients, 3 died of causes unrelated to the HAV. One patient had required thrombectomy twice, with secondary patency achieved. No other interventions were recorded between 24 and 72 months. At 72 months, five patients had a patent HAV, including four patients with primary patency. For the entire study population from day 1 to month 72, the overall primary, primary assisted, and secondary patency rate estimated using Kaplan-Meier analysis was 44%, 45%, and 60% respectively, with censoring for death. No patient had experienced rejection or infection of the HAV, and no patient had required amputation of the implanted limb. Conclusions: The infection-resistant, off-the-shelf HAV could provide a durable alternative conduit in the arterial circuit setting to restore the lower extremity blood supply in patients with PAD, with remodeling into the recipient's own vessel over time. The HAV is currently being evaluated in seven clinical trials to treat PAD, vascular trauma, and as a hemodialysis access conduit.

Five Year Outcomes in Patients with End Stage Renal Disease Who Received a Bioengineered Human Acellular Vessel for Dialysis Access.

OBJECTIVE: Patients with end stage renal failure who require haemodialysis suffer morbidity and mortality due to vascular access. Bioengineered human acellular vessels (HAVs) may provide a haemodialysis access option with fewer complications than other grafts. In a prospective phase II trial from 2012 to 2014 (NCT01744418), HAVs were implanted into 40 haemodialysis patients at three sites in Poland. The trial protocol for this "first in man" use of the HAV contemplated only two years of follow up, and the trial results were initially reported in 2016. In light of the retained HAV function seen in many of the patients at the two year time point, follow up for patients who were still alive was extended to a total of 10 years. This interim follow up report, at the long term time point of five years, assessed patient and conduit status in those who continued routine dialysis with the HAV. METHODS: HAVs are bioengineered by culturing human vascular smooth muscle cells on a biodegradable polymer matrix. In this study, patients with patent HAV implants at 24 months were followed every three months, starting at month 27 through to month 60, or at least five years post-implantation. This report contains the follow up functional and histological data on 29 of the original 40 patients who demonstrated HAV function at the 24 month time point. RESULTS: Eleven patients completed at month 60. One patient maintained primary patency, and 10 maintained secondary patency. Secondary patency was estimated at 58.2% (95% confidence interval 39.2-73.1) at five years, after censoring for deaths (n = 8) and withdrawals (n = 1). No HAV conduit infections were reported during the follow up period. CONCLUSION: This phase II long term follow up shows that the human acellular vessel (HAV) may provide durable and functional haemodialysis access for patients with end stage renal disease.

Strategy of pulseless pink supracondylar humerus fracture treatment in children: a comparison of two approaches.

PURPOSE: The appropriate treatment of pulseless pink supracondylar humerus fractures (SCHF) remains controversial. In this study, the outcomes of two treatment approaches (with and without vascular surgery) were compared. MATERIAL AND METHODS: This was a retrospective multicenter study of patients with pulseless pink SCHFs treated in ten pediatric surgery, trauma, or orthopedics departments in the Czech and Slovak Republic between 2014 and 2018. RESULTS: Of the total 3608 cases of displaced SCHF, 125 had the pulseless pink SCHF. Of those, 91% (114/125) did not undergo vascular surgery and 9% (11/125) underwent vascular surgery. The patients who did undergo vascular surgery had radial artery pulsation restored more frequently in the operating room (73% vs. 36%; p = 0.02), within 6 h (91% vs. 45%; p = 0.004), and within 24 h of surgery (91% vs. 57%; p = 0.05). However, 72 h after surgery, there was no significant difference in palpable radial artery pulsation between the vascular surgery and the non-vascular surgery groups (91% vs. 74%; p = 0.24). Additionally, no significant differences in long-term neurological (9% vs. 22%; p = 0.46) or circulatory (9% vs. 7%; p = 0.57) deficits were found between the two groups. CONCLUSION: While vascular surgery in patients with pulseless pink SCHFs is associated with a more prompt restoration of radial artery pulsation, no statistical significant differences in terms of the restoration of neurological deficits or the risks of long-term neurological or circulatory deficits were found between patients with and without vascular surgery.

Arterial reconstruction with human bioengineered acellular blood vessels in patients with peripheral arterial disease.

OBJECTIVE: Vascular conduit is essential for arterial reconstruction for a number of conditions, including trauma and atherosclerotic occlusive disease. We have developed a tissue-engineered human acellular vessel (HAV) that can be manufactured, stored on site at hospitals, and be immediately available for arterial vascular reconstruction. Although the HAV is acellular when implanted, extensive preclinical and clinical testing has demonstrated that the HAV subsequently repopulates with the recipient's own vascular cells. We report a first-in-man clinical experience using the HAV for arterial reconstruction in patients with symptomatic peripheral arterial disease. METHODS: HAVs were manufactured using human vascular smooth muscle cells grown on a biodegradable scaffold. After the establishment of adequate cell growth and extracellular matrix deposition, the vessels were decellularized to remove human cellular antigens. Manufactured vessels were implanted in 20 patients with symptomatic peripheral arterial disease as above-knee, femoral-to-popliteal arterial bypass conduits. After HAV implantation, all patients were assessed for safety, HAV durability, freedom from conduit infection, and bypass patency for 2 years. RESULTS: Twenty HAVs were placed in the arterial, above-knee, femoral-to-popliteal position in patients with rest pain (n = 3) or symptomatic claudication (n = 17). All HAVs functioned as intended and had no evidence of structural failure or rejection by the recipient. No acute HAV infections were reported, but three surgical site infections were documented during the study period. Three non-HAV-related deaths were reported. One vessel developed a pseudoaneurysm after suspected iatrogenic injury during a balloon thrombectomy. No amputations of the HAV implanted limb occurred over the 2-year period, and no HAV infections were reported in approximately 34 patient-years of continuous patient follow-up. CONCLUSIONS: Human tissue engineered blood vessels can be manufactured and readily available for peripheral arterial bypass surgery. Early clinical experience with these vessels, in the arterial position, suggest that they are safe, have acceptable patency, a low incidence of infection, and do not require the harvest of autologous vein or any cells from the recipient. Histologic examination of tissue biopsies revealed vascular remodeling and repopulation by host cells. This first-in-man arterial bypass study supports the continued development of human tissue engineered blood vessels for arterial reconstruction, and potential future expansion to clinical indications including vascular trauma and repair of other size-appropriate peripheral arteries.

The ultrasonography evaluation of talar dysplasia as a potential prognostic factor for predicting the course and outcomes of clubfoot deformity treatment using Ponseti technique.

OBJECTIVE: The aim of this study was to assess the role of sonographic evaluation of Talar dysplasia in predicting the outcome of standard Ponseti method in the treatment of clubfoot deformity. METHODS: A total 23 children (15 boys and 8 girls; mean age: 18.2 ± 5.4 days (8-32)) who underwent Ponseti treatment were included in the study. Before the treatment, maximal talus length of affected and non-affected feet were measured by US and relative talar dysplasia ratio (RTDR) was calculated. The patients were categorized 2 groups according to RTDR: group A - mild and group B - severe deformity. Pirani score was used for clinical evaluation. The groups were compared in terms of number of the applied casts, need of percutaneous tenotomy of Achilles tendon (AchT) and frequency of deformity recurrence. RESULTS: Pirani score was 4.46 for population (4.33 for group A; 4.54 for group B). Number of casts significantly differed between groups (p < 0.001) and positive correlation was found (r = 0.851, p < 0.001). AchT was performed in 56% cases for group A and in 86% cases for group B; no statistically significant difference was obtained (p = 0.162). Recurrence occurred in 2 patients belonging to group B without significant difference compared to group A (p = 0.502). CONCLUSION: Talar dysplasia assessment appeared as a promising prognostic factor for predicting the outcome of the Ponseti technique in treatment of clubfoot deformity. LEVEL OF EVIDENCE: Level IV, diagnostic study.

Contrast Media Administration in Coronary Computed Tomography Angiography - A Systematic Review.

Background Various different injection parameters influence enhancement of the coronary arteries. There is no consensus in the literature regarding the optimal contrast media (CM) injection protocol. The aim of this study is to provide an update on the effect of different CM injection parameters on the coronary attenuation in coronary computed tomographic angiography (CCTA). Method Studies published between January 2001 and May 2014 identified by Pubmed, Embase and MEDLINE were evaluated. Using predefined inclusion criteria and a data extraction form, the content of each eligible study was assessed. Initially, 2551 potential studies were identified. After applying our criteria, 36 studies were found to be eligible. Studies were systematically assessed for quality based on the validated Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-II checklist. Results Extracted data proved to be heterogeneous and often incomplete. The injection protocol and outcome of the included publications were very diverse and results are difficult to compare. Based on the extracted data, it remains unclear which of the injection parameters is the most important determinant for adequate attenuation. It is likely that one parameter which combines multiple parameters (e. g. IDR) will be the most suitable determinant of coronary attenuation in CCTA protocols. Conclusion Research should be directed towards determining the influence of different injection parameters and defining individualized optimal IDRs tailored to patient-related factors (ideally in large randomized trials). Key points · This systematic review provides insight into decisive factors on coronary attenuation.. · Different and contradicting outcomes are reported on coronary attenuation in CCTA.. · One parameter combining multiple parameters (IDR) is likely decisive in coronary attenuation.. · Research should aim at defining individualized optimal IDRs tailored to individual factors.. · Future directions should be tailored towards the influence of different injection parameters.. Citation Format · Mihl C, Maas M, Turek J et al. Contrast Media Administration in Coronary Computed Tomography Angiography - A Systematic Review. Fortschr Röntgenstr 2017; 189: 312 - 325.

Bioengineered human acellular vessels for dialysis access in patients with end-stage renal disease: two phase 2 single-arm trials.

BACKGROUND: For patients with end-stage renal disease who are not candidates for fistula, dialysis access grafts are the best option for chronic haemodialysis. However, polytetrafluoroethylene arteriovenous grafts are prone to thrombosis, infection, and intimal hyperplasia at the venous anastomosis. We developed and tested a bioengineered human acellular vessel as a potential solution to these limitations in dialysis access. METHODS: We did two single-arm phase 2 trials at six centres in the USA and Poland. We enrolled adults with end-stage renal disease. A novel bioengineered human acellular vessel was implanted into the arms of patients for haemodialysis access. Primary endpoints were safety (freedom from immune response or infection, aneurysm, or mechanical failure, and incidence of adverse events), and efficacy as assessed by primary, primary assisted, and secondary patencies at 6 months. All patients were followed up for at least 1 year, or had a censoring event. These trials are registered with ClinicalTrials.gov, NCT01744418 and NCT01840956. FINDINGS: Human acellular vessels were implanted into 60 patients. Mean follow-up was 16 months (SD 7·6). One vessel became infected during 82 patient-years of follow-up. The vessels had no dilatation and rarely had post-cannulation bleeding. At 6 months, 63% (95% CI 47-72) of patients had primary patency, 73% (57-81) had primary assisted patency, and 97% (85-98) had secondary patency, with most loss of primary patency because of thrombosis. At 12 months, 28% (17-40) had primary patency, 38% (26-51) had primary assisted patency, and 89% (74-93) had secondary patency. INTERPRETATION: Bioengineered human acellular vessels seem to provide safe and functional haemodialysis access, and warrant further study in randomised controlled trials. FUNDING: Humacyte and US National Institutes of Health.

Evaluation of individually body weight adapted contrast media injection in coronary CT-angiography.

OBJECTIVES: Contrast media (CM) injection protocols should be customized to the individual patient. Aim of this study was to determine if software tailored CM injections result in diagnostic enhancement of the coronary arteries in computed tomography angiography (CTA) and if attenuation values were comparable between different weight categories. MATERIALS AND METHODS: 265 consecutive patients referred for routine coronary CTA were scanned on a 2nd generation dual-source CT. Group 1 (n=141) received an individual CM bolus based on weight categories (39-59 kg; 60-74 kg; 75-94 kg; 95-109 kg) and scan duration ('high-pitch: 1s; "dual-step prospective triggering": 7s), as determined by contrast injection software (Certegra™ P3T, Bayer, Berlin, Germany). Group 2 (n=124) received a standard fixed CM bolus; Iopromide 300 mgI/ml; volume: 75 ml; flow rate: 7.2 ml/s. Contrast enhancement was measured in all proximal and distal coronary segments. Subjective and objective image quality was evaluated. Statistical analysis was performed using SPSS (IBM, version 20.0). RESULTS: For group 1, mean attenuation values of all segments were diagnostic (>325 HU) without statistical significant differences between different weight categories (p>0.17), proximal vs. distal: 449 ± 65-373 ± 58 HU (39-59 kg); 443 ± 69-367 ± 81 HU (60-74 kg); 427 ± 59-370 ± 61 HU (75-94 kg); 427 ± 73-347 ± 61 HU (95-109 kg). Mean CM volumes were: 55 ± 6 ml (39-59 kg); 61 ± 7 ml (60-74 kg); 71 ± 8 ml (75-94 kg); 84 ± 9 ml (95-109 kg). For group 2, mean attenuation values were not all diagnostic with differences between weight categories (p<0.01), proximal vs. distal: 611 ± 142-408 ± 69 HU (39-59 kg); 562 ± 135-389 ± 98 HU (60-74 kg); 481 ± 83-329 ± 81 HU (75-94 kg); 420 ± 73-305 ± 35 HU (95-109 kg). Comparable image noise and image quality were found between groups (p ≥ 0.330). CONCLUSIONS: Individually tailored CM injection protocols yield diagnostic attenuation and a more homogeneous enhancement pattern between different weight groups. CM volumes could be reduced for the majority of patients utilizing individualized CM bolus application.

Low contrast media volume in pre-TAVI CT examinations.

PURPOSE: To evaluate image quality using reduced contrast media (CM) volume in pre-TAVI assessment. METHODS: Forty-seven consecutive patients referred for pre-TAVI examination were evaluated. Patients were divided into two groups: group 1 BMI < 28 kg/m(2) (n = 29); and group 2 BMI > 28 kg/m(2) (n = 18). Patients received a combined scan protocol: retrospective ECG-gated helical CTA of the aortic root (80kVp) followed by a high-pitch spiral CTA (group 1: 70 kV; group 2: 80 kVp) from aortic arch to femoral arteries. All patients received one bolus of CM (300 mgI/ml): group 1: volume = 40 ml; flow rate = 3 ml/s, group 2: volume = 53 ml; flow rate = 4 ml/s. Attenuation values (HU) and contrast-to-noise ratio (CNR) were measured at the levels of the aortic root (helical) and peripheral arteries (high-pitch). Diagnostic image quality was considered sufficient at attenuation values > 250HU and CNR > 10. RESULTS: Diagnostic image quality for TAVI measurements was obtained in 46 patients. Mean attenuation values and CNR (HU ± SD) at the aortic root (helical) were: group 1: 381 ± 65HU and 13 ± 8; group 2: 442 ± 68HU and 10 ± 5. At the peripheral arteries (high-pitch), mean values were: group 1: 430 ± 117HU and 11 ± 6; group 2: 389 ± 102HU and 13 ± 6. CONCLUSION: CM volume can be substantially reduced using low kVp protocols, while maintaining sufficient image quality for the evaluation of aortic root and peripheral access sites. KEY POINTS: • Image quality could be maintained using low kVp scan protocols. • Low kVp protocols reduce contrast media volume by 34-67 %. • Less contrast media volume lowers the risk of contrast-induced nephropathy.

Automated Tube Voltage Selection for Radiation Dose Reduction in CT Angiography Using Different Contrast Media Concentrations and a Constant Iodine Delivery Rate.

OBJECTIVE: The purpose of this study was to systematically investigate radiation dose reduction using automated tube voltage selection during CT angiography (CTA) and to evaluate the impact of contrast medium (CM) injection protocols on dose reduction. MATERIALS AND METHODS: A circulation phantom containing the thoracic and abdominal vasculature was used. Four different concentrations of CM (iopromide 300 and 370 mg I/mL and iomeprol 350 and 400 mg I/mL) were administered while maintaining an identical iodine delivery rate (1.8 g I/s) and total iodine load (20.0 g). Three different scanning protocols for CTA of the thoracoabdominal aorta were used: protocol A, no dose modulation; protocol B, automated tube current modulation (CARE Dose4D); and protocol C, automated tube voltage selection (CARE kV). The dose-length product was recorded to calculate the effective dose. Attenuation values (in Hounsfield units), image noise levels, and signal-to-noise ratios (SNRs) in six predefined intravascular sites (three thoracic and three abdominal) were measured by two readers. All values were analyzed using the Kruskal-Wallis test and two-way ANOVA. RESULTS: There was a significant reduction in the effective dose (in millisieverts) for protocols B (mean ± SD, 2.03 ± 0.1 mSv) and C (1.00 ± 0.0 mSv) compared with protocol A (4.34 ± 0.0 mSv). The dose was reduced by 53% for protocol B and by 77% for protocol C. No significant differences were found in the effective dose among the different CM injection protocols within the scanning protocols; all p values were > 0.05. The attenuation values and SNRs were comparable among all the different CM injection protocols; all p values were > 0.05. CONCLUSION: A large radiation dose reduction (77%) can be achieved using automated tube voltage selection independent of the CM injection protocol.

Computed Tomography Angiography With High Flow Rates: An In Vitro and In Vivo Feasibility Study.

OBJECTIVE: The aims of this study were to test high-flow application of contrast media (CM) using novel high-flow needles and to assess injection- and flow-related parameters in a circulation phantom and in an in vivo population. MATERIALS AND METHODS: A circulation phantom simulating physiological parameters was used. Preheated CM (300 mg/mL) was injected at flow rates varying between 5 and 15 mL/s through a novel 18-gauge high-flow intravenous injection needle. In addition, feasibility of these high-flow needles was tested with administration of flow rates of 9 mL/s in 20 patients referred for pre-transcatheter aortic valve implantation assessment. Injection parameters (eg, peak pressures, peak flow rates) in both phantom and in vivo setup were continuously monitored by a data acquisition program. Attenuation at predefined levels of the aorta (eg, aortic root to common femoral arteries) was measured in all patients to determine clinical applicability. RESULTS: In the phantom setup, injection rates up to 15 mL/s were feasible. An enhancement plateau was reached at 11 mL/s (464 [20] HU). In patients, no pressure- or flow-related complications (eg, extravasation) were recorded (mean [SD] peak pressure, 154 [8] psi; mean [SD] peak flow rate, 9.2 [0.1 mL/s; range, 9.1-9.6]). Diagnostic attenuation values were reached at all predefined levels of the aorta (330.8 [113.1] HU to 622.9 [81.5] HU). CONCLUSIONS: These results indicate that injections with 9 mL/s using high-flow injection needles are safe. The pressure limit of 325 psi was not reached, and the injections resulted in diagnostic attenuation values. Using this dedicated needle, high flow rates should not be considered a drawback for CM application in routine CT angiography examinations.

MDCT evaluation of aortic root and aortic valve prior to TAVI. What is the optimal imaging time point in the cardiac cycle?

OBJECTIVES: To determine the optimal imaging time point for transcatheter aortic valve implantation (TAVI) therapy planning by comprehensive evaluation of the aortic root. METHODS: Multidetector-row CT (MDCT) examination with retrospective ECG gating was retrospectively performed in 64 consecutive patients referred for pre-TAVI assessment. Eighteen different parameters of the aortic root were evaluated at 11 different time points in the cardiac cycle. Time points at which maximal (or minimal) sizes were determined, and dimension differences to other time points were evaluated. Theoretical prosthesis sizing based on different measurements was compared. RESULTS: Largest dimensions were found between 10 and 20% of the cardiac cycle for annular short diameter (10%); mean diameter (10%); effective diameter and circumference-derived diameter (20%); distance from the annulus to right coronary artery ostium (10%); aortic root at the left coronary artery level (20%); aortic root at the widest portion of coronary sinuses (20%); and right leaflet length (20%). Prosthesis size selection differed depending on the chosen measurements in 25-75% of cases. CONCLUSION: Significant changes in anatomical structures of the aortic root during the cardiac cycle are crucial for TAVI planning. Imaging in systole is mandatory to obtain maximal dimensions. KEY POINTS: • Most aortic root structures undergo significant dimensional changes throughout the cardiac cycle. • The largest dimensions of aortic parameters should be determined to optimize TAVI. • Circumference-derived diameter showed maximum dimension at 20% of the cardiac cycle.

Robot-assisted right colectomy: surgical technique and review of the literature.

Following the successful introduction of robotic surgery to the field of urology and gynecology, its use gained even more interest among those in the field of colorectal surgery. Rectal resection is believed to be among the best suited for robotic assistance. In particular, the right hemicolectomy procedure has been proposed as a training tool in order to gain clinical experience with the robot. This article and attached video demonstrates, in detail, the robot-assisted right hemicolectomy, including key landmarks of the procedure. The case presented involved a 58-year-old man with an advanced cecal adenocarcinoma. In our opinionrobot-assisted right colon resection is a procedure that offers particular value for the novice robotic team who is in the beginning stages of their colorectal surgery experience. Although no concrete advantages for use of the robot in this particular procedure have been demonstrated in the literature, because it is a relatively straightforward and simple procedure, it can serve as a valuable training tool for the novice robotic surgeon.

The clinicopathological determinants of native arteriovenous fistula failure in patients on maintenance hemodialysis.

BACKGROUND: Progressive narrowing of the venous part of dialysis fistulae is caused by hemodynamic and inflammatory factors. OBJECTIVES: The pathogenic and clinical determinants of deterioration of the functioning of arteriovenous fistulae in chronically hemodialyzed patients were evaluated. MATERIAL AND METHODS: The hemodynamic parameters and the activity of inflammatory growth factors in the vessel wall of newly implanted fistulae were assessed and correlated with the clinical course of 34 hemodialyzed patients. Measurements taken at the time of implanting the fistulae included blood flow in the venous part of the anastomosis and its widest diameter by ultrasound Power Doppler, a histopathologic examination of fistula wall samples and measurements of mRNA expression for growth factors PDGFß1 and TGFß in the fistula wall. The results were correlated with clinical data from 36 months' observation: duration of fistula maturation, adequacy of dialysis treatment (eKt/V), the patient's survival, morbidity linked with vascular access problems and general cardiovascular morbidity. RESULTS: The mean duration of fistula maturation was 44.9 days (N = 43, SD = 38.6), whereas the average duration of fistula usage as dialysis access was 795.9 ± 480.6 days. Fistula blood flow at the time of implantation, averaged 1782.2 ± 1735.3 ml/min. The mean number of hospitalization days due to vascular access morbidity was 9.9 ± 15.6 days and it correlated positively with the fistula blood flow (R = 0.596, P = 0.004). There was a negative correlation between the expression of PDGFß1 mRNA and fistula blood flow (R = -0.673, P = 0.011), as well as between TGFß expression and patient survival (R = -0.722, P = 0.002). CONCLUSIONS: Inflammatory activity of the vessel wall growth factors PDGFß1 and TGFß implies impairment of fistula function and the patient's cardiovascular morbidity.