Can diltiazem be given to patients with heart failure?

Diltiazem Use in Heart Failure Patients

Diltiazem should not be used in patients with heart failure with reduced ejection fraction (HFrEF) as it can worsen heart failure symptoms and lead to clinical deterioration. 1, 2, 3

Contraindications and Concerns

Diltiazem is specifically contraindicated in:

• Patients with decompensated systolic heart failure 1
• Patients with severe left ventricular dysfunction 1
• Heart failure with reduced ejection fraction (HFrEF) 2

The American Heart Association advises against using non-dihydropyridine calcium channel blockers (including diltiazem) in HFrEF as they can worsen outcomes 2. This is due to diltiazem's negative inotropic effects that can further depress myocardial contractility in already compromised hearts 3.

Specific Heart Failure Scenarios

Heart Failure with Reduced Ejection Fraction (HFrEF)

• Avoid diltiazem - The drug label clearly warns about its negative inotropic effects and potential to worsen heart failure 3
• Recent research shows that diltiazem use in HFrEF patients resulted in increased clinical deterioration (33% vs 21%, p=0.044), including increased need for inotropes, vasopressors, and ICU transfers 4

Heart Failure with Preserved Ejection Fraction (HFpEF)

• Diltiazem may be used with caution in HFpEF patients 1
• The European Society of Cardiology indicates that calcium channel blockers like diltiazem can be used in HFpEF patients, often with digoxin for rate control in atrial fibrillation 1
• However, combining diltiazem with beta-blockers in atrial fibrillation patients with HFpEF is not recommended 1

Special Considerations for Atrial Fibrillation with Heart Failure

When managing atrial fibrillation in heart failure patients:

1. For HFrEF patients with AF:

   • Beta-blockers are the first-line rate control medication
   • Digoxin can be used as an adjunctive medication
   • Avoid diltiazem 1

2. For HFpEF patients with AF:

   • Diltiazem can be used with caution
   • Avoid combining diltiazem with beta-blockers 1

3. For emergency situations:

   • In patients with hemodynamic instability, emergent cardioversion is recommended rather than medication 1
   • For patients with volume overload, intravenous digoxin is preferred over diltiazem 1

Recent Research Findings

While older small studies from the 1980s suggested potential hemodynamic benefits of diltiazem in some heart failure patients 5, 6, more recent and robust evidence contradicts these findings:

• A 2024 study showed increased clinical deterioration in HFrEF patients who received diltiazem despite warnings from clinical decision support systems 4
• A 2024 observational study found that worsening heart failure occurred in 17% of patients with reduced EF who received IV diltiazem for atrial fibrillation management, compared to only 4.8% in those with preserved EF (p=0.005) 7

Practical Recommendations

1. For rate control in AF with heart failure:

   • HFrEF: Use beta-blockers and/or digoxin
   • HFpEF: Diltiazem may be used cautiously, but monitor for signs of worsening heart failure

2. When considering diltiazem in any heart failure patient:

   • Check ejection fraction before administration
   • Implement clinical decision support systems to prevent inappropriate use
   • Monitor closely for signs of clinical deterioration if used in HFpEF

3. Alternative rate control strategies for HFrEF patients:

   • Beta-blockers (metoprolol, carvedilol, bisoprolol)
   • Digoxin
   • Amiodarone in selected cases
   • Consider catheter ablation in refractory cases

Conclusion

The evidence strongly supports avoiding diltiazem in patients with HFrEF due to increased risk of clinical deterioration. While diltiazem may be used with caution in HFpEF patients, alternative rate control strategies should be considered first, especially in patients with any signs of decompensation.