Do patients with Heart Failure with Reduced Ejection Fraction (HFrEF) undergoing hemodialysis require low Blood Flow Rates (BFR) and Dialysate Flow Rates (DFR)?

Blood Flow Rate and Dialysate Flow Rate in HFrEF Patients on Hemodialysis

No, HFrEF patients on hemodialysis do NOT require intentionally low blood flow rates (BFR) or dialysate flow rates (DFR)—in fact, they should maintain adequate BFR ≥300 mL/min to ensure dialysis adequacy, as low BFR leads to underdialysis, increased morbidity, and mortality. 1

Understanding the Question Context

The question appears to conflate two distinct clinical issues:

• Hemodialysis parameters (BFR/DFR for dialysis adequacy)
• Systemic blood pressure management in HFrEF patients

These are separate considerations that require different management approaches.

Hemodialysis Blood Flow Rate Requirements

Target BFR for Adequate Dialysis

• BFR ≥300 mL/min is the minimum acceptable standard for adequate dialysis delivery in all patients, including those with HFrEF 1
• BFR <300 mL/min results in:
  • Extended treatment times that still often result in underdialysis due to unrecognized recirculation 1
  • Inadequate urea reduction ratio (URR <65% or Kt/V <1.2) 1
  • Increased economic expenditures, morbidity, and mortality 1

Clinical Implications of Low BFR

• Low BFR is a sign of catheter dysfunction, not a therapeutic target 1
• 15% of treatments with catheters demonstrate BFR <300 mL/min, indicating access problems requiring intervention 1
• Catheter dysfunction leads to 17-33% of untimely catheter removals and 30-40% access loss from thrombosis 1

Managing HFrEF Patients on Dialysis

Dialysis Modality Considerations

• Peritoneal dialysis or more frequent/longer hemodialysis sessions may be better tolerated in HFrEF patients due to slower ultrafiltration rates, resulting in less intradialytic hypotension and better volume control 2
• Dialysate cooling and higher dialysate calcium may provide additional hemodynamic benefits 2

Medication Management During Dialysis

The primary concern is optimizing guideline-directed medical therapy (GDMT) for HFrEF, not restricting dialysis parameters:

• All four foundational GDMT classes should be initiated even in dialysis patients with HFrEF: ARNI/ACEi/ARB, beta-blocker, MRA, and SGLT2 inhibitor 3
• SGLT2 inhibitors and MRAs should be started first as they have minimal blood pressure effects 4, 5
• Beta-blockers and ACEi/ARB/ARNI use is common in dialysis patients despite limited trial data 2

Blood Pressure Management Considerations

Low systemic blood pressure in HFrEF does NOT necessitate low dialysis BFR:

• Asymptomatic low blood pressure (even <90 mmHg systolic) is NOT a contraindication to GDMT and should not prevent dialysis adequacy 1, 5, 3
• The association between low BP and mortality is attenuated in HFrEF patients on optimized GDMT 1
• Symptomatic hypotension or SBP <80 mmHg requires immediate intervention, but this involves medication adjustment and volume management—not reducing dialysis BFR 1

Practical Algorithm for HFrEF Patients on Hemodialysis

Step 1: Ensure Dialysis Adequacy

• Maintain BFR ≥300 mL/min (ideally 400 mL/min or greater with properly placed catheters) 1
• Monitor prepump arterial pressure to ensure valid blood flows 1
• Regular assessment of URR (target ≥65%) or Kt/V (target ≥1.2) 1

Step 2: Optimize Volume Status

• Assess for volume overload as the primary driver of cardiac symptoms 4
• Adjust ultrafiltration goals based on clinical assessment, not by reducing BFR 2
• Consider longer or more frequent dialysis sessions if hemodynamic instability occurs 2

Step 3: Initiate GDMT Sequentially

• Start SGLT2 inhibitor and MRA first (minimal BP effects) 4, 5
• Add low-dose beta-blocker if heart rate >70 bpm 4
• Add low-dose ARNI/ACEi/ARB if heart rate <70 bpm 4
• Uptitrate medications every 1-2 weeks as tolerated 3

Step 4: Monitor for Complications

• Follow-up within 1-2 weeks after each medication adjustment to assess BP, heart rate, renal function, electrolytes, and volume status 4
• If BFR drops below 300 mL/min, investigate for catheter dysfunction requiring intervention 1

Common Pitfalls to Avoid

• Do not intentionally reduce BFR to "protect" hemodynamics—this leads to underdialysis and worse outcomes 1
• Do not withhold GDMT due to low BP alone unless symptomatic or SBP <80 mmHg 1, 5, 3
• Do not confuse intradialytic hypotension with the need for low BFR—address this through ultrafiltration rate adjustment, dialysis duration, and modality choice 2
• Do not delay referral to advanced HF programs if persistent hypotension prevents GDMT optimization or recurrent hospitalizations occur 4, 3

Evidence Limitations

• Dialysis patients were excluded from major HFrEF trials, resulting in limited high-quality evidence for medication use in this population 2, 6
• Most evidence for GDMT safety and efficacy extends only to CKD stage 3B (eGFR ≥30 mL/min/1.73 m²), with limited data for stage 4 and virtually no data for stage 5 or dialysis patients 6
• Despite limited evidence, clinical practice supports GDMT use in dialysis patients based on extrapolation from non-dialysis populations 2