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Published on: October 2, 2020
Beyond the vascular access: unveiling the cardiovascular impact of dialysis access flow rates
Mohammad Moradmand1, Farzad Dehghani Mahmoudabadi2, Mohammad Javanbakht3
1Department of General Surgery, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Insights
High-flow arteriovenous access in hemodialysis patients significantly impacts cardiac function, decreasing ejection fraction and increasing left ventricular dimensions. Proactive cardiovascular monitoring is crucial, especially for high-flow access, to prevent heart failure.
Area of Science:
- Nephrology
- Cardiology
- Vascular Surgery
Background:
- Hemodialysis necessitates reliable vascular access, typically arteriovenous fistulas (AVFs) or grafts (AVGs).
- The hemodynamic impact of vascular access, particularly high-flow states, on cardiac function requires further investigation.
Purpose of the Study:
- To evaluate the effects of arteriovenous fistula (AVF) and arteriovenous graft (AVG) flow rates on cardiac function and blood pressure in hemodialysis patients.
- To compare cardiovascular changes before and after vascular access creation and differentiate outcomes between high-flow and non-high-flow access groups.
Main Methods:
- Prospective observational study of 80 hemodialysis patients in Tehran, Iran.
- Vascular access flow rates (Qa) measured by Color Doppler ultrasonography.
- Echocardiographic parameters (systolic blood pressure, ejection fraction, left ventricular end-diastolic dimension) assessed at baseline and 6 months post-intervention.
Main Results:
- Significant post-access creation decrease in systolic blood pressure (156.48 to 141.42 mmHg) and ejection fraction (57.18% to 50.31%).
- Significant increase in left ventricular end-diastolic dimension (4.43 to 5.51 cm), indicating cardiac burden.
- High-flow access correlated with greater cardiovascular burden, suggesting a risk of high-output heart failure.
Conclusions:
- High-flow vascular access in hemodialysis patients poses a significant cardiovascular burden, necessitating vigilant monitoring.
- Early detection of high-risk patients through routine Doppler ultrasonography and echocardiography is vital for timely intervention and prevention of complications like high-output cardiac failure.
Objective:
To investigate the impact of arteriovenous fistula (AVF) and arteriovenous graft (AVG) flow rates on cardiac function and blood pressure in hemodialysis patients, comparing changes before and after vascular access creation and assessing differences between high and non-high flow access groups.
Methods:
This prospective, observational study included 80 hemodialysis patients (43 males), all of Iranian ethnicity, at a university-affiliated referral hospital in Tehran, Iran. Flow rates (Qa) of vascular accesses were measured using Color Doppler ultrasonography (Acuson Sequoia system). Echocardiographic parameters, including systolic blood pressure, ejection fraction (EF), and left ventricular end-diastolic dimension (LVEDD), were assessed at baseline and six months post-intervention. Data were analyzed using paired t-tests and Pearson correlation coefficients.
Results:
Following vascular access creation, a significant decrease in systolic blood pressure was observed (156.48 ± 18.04 mmHg to 141.42 ± 15.82 mmHg, p < 0.001), along with a notable decline in EF (57.18% ± 6.51 to 50.31% ± 4.99, p < 0.001), and an increase in LVEDD (4.43 ± 0.27 cm to 5.51 ± 0.26 cm, p < 0.001), suggesting potential cardiovascular burden in high-flow access patients. Patients with high-flow access exhibited greater cardiovascular burden, likely due to increased cardiac output demands and risk of high-output heart failure. No significant differences in cardiac outcomes were observed between proximal and distal AVFs or upper and lower limb AVGs.
Conclusions:
These findings underscore the need for proactive cardiovascular monitoring, particularly in patients with high-flow vascular access, to prevent potential complications such as high-output cardiac failure. Routine Doppler ultrasonography and echocardiographic assessments should be integrated into clinical practice to identify high-risk patients and guide timely interventions.
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