Is systolic blood pressure control more important to target in patients with a weak heart?

Systolic Blood Pressure Control in Heart Failure

In patients with heart failure, targeting systolic blood pressure below 130 mmHg is recommended to reduce cardiovascular events and mortality, particularly for those with preserved ejection fraction. 1, 2

Blood Pressure Targets in Heart Failure

Heart Failure with Reduced Ejection Fraction (HFrEF)

• The ACC/AHA guidelines recommend controlling both systolic and diastolic hypertension in heart failure patients, with target levels lower than those for uncomplicated hypertension (less than 130 mm Hg systolic and less than 80 mm Hg diastolic) 1
• Systolic blood pressure control is particularly important as:
  • Hypertension exerts deleterious effects on ventricular function through structural and functional changes
  • Increases in systolic blood pressure slow myocardial relaxation 1
  • Resulting hypertrophy adversely affects passive chamber stiffness

Heart Failure with Preserved Ejection Fraction (HFpEF)

• A recent pooled analysis of 4 major HFpEF trials (I-PRESERVE, TOPCAT-Americas, PARAGON-HF, and DELIVER) found a J-shaped relationship between SBP and cardiovascular outcomes 2
• The lowest risk was observed at SBP levels between 120-130 mmHg 2
• Higher pulse pressure was associated with greater cardiovascular risk regardless of SBP 2

Evidence Supporting Lower Systolic Targets

The 2018 ACC/AHA systematic review found that BP lowering to a target of <130 mmHg may reduce the risk of several important outcomes including 1:

• Myocardial infarction
• Stroke
• Heart failure
• Major cardiovascular events

This is consistent with findings from the SPRINT trial, which demonstrated a 25% reduction in the primary composite outcome (MI, stroke, heart failure, or CV death) with intensive blood pressure control (target <120 mmHg) compared to standard treatment (target <140 mmHg) 1.

Special Considerations in Heart Failure Patients

Potential Risks of Aggressive BP Lowering

• A study of hospitalized older patients with HFrEF found that SBP <130 mmHg was associated with poor outcomes 3
• This association persisted even when excluding patients with SBP <110 mmHg 3
• Hypotension may be a significant problem, especially in the elderly, as they can be quite sensitive to preload reduction 1

Medication Selection

• ACE inhibitors are often drugs of choice for initial management of hypertension in heart failure 1, 4
• Lisinopril is indicated to reduce signs and symptoms of systolic heart failure 4
• Spironolactone is indicated for treatment of NYHA Class III-IV heart failure and reduced ejection fraction 5
• Beta-blockers, digoxin, and some calcium channel blockers can provide symptomatic relief in patients with HF by slowing heart rate 1

Practical Approach to BP Management in Heart Failure

1. Measure BP properly using standardized techniques 1

   • Rest period of at least 5 minutes
   • Average of 2-3 readings
   • Proper patient positioning with back support and arm at heart level

2. Set appropriate targets based on heart failure type:

   • For HFrEF: Target SBP <130 mmHg 1
   • For HFpEF: Target SBP 120-130 mmHg (optimal range with lowest risk) 2

3. Monitor for adverse effects of intensive blood pressure control 1:

   • Hypotension
   • Syncope
   • Electrolyte abnormalities
   • Acute kidney injury
   • Orthostatic changes (especially in elderly patients) 6

4. Adjust medication regimen to achieve targets while minimizing side effects:

   • Start with ACE inhibitors or ARBs 1
   • Add diuretics to reduce ventricular filling pressures 1
   • Consider beta-blockers for rate control and symptom relief 1
   • Add spironolactone for NYHA Class III-IV HF with reduced EF 5

Conclusion

Systolic blood pressure control is indeed more important to target in patients with heart failure, with evidence supporting targets below 130 mmHg to reduce cardiovascular events and mortality. However, careful monitoring for adverse effects is essential, particularly in elderly patients who may be more sensitive to aggressive blood pressure lowering. The optimal range appears to be 120-130 mmHg, especially for those with preserved ejection fraction, as both too high and too low systolic blood pressure can be associated with adverse outcomes.