Can Cardizem (Diltiazem) be given to a patient with atrial fibrillation (AFib) with rapid ventricular response (RVR), undergoing hemodialysis, and having congestive heart failure (CHF)?

From the Guidelines

Cardizem (diltiazem) should be used with caution in patients with atrial fibrillation with rapid ventricular response (RVR) who have congestive heart failure (CHF) and are on hemodialysis, as it may worsen heart failure due to its negative inotropic effects, as noted in the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation 1. For these patients, beta-blockers like metoprolol are generally preferred as first-line rate control agents. If diltiazem is used, it should be at reduced doses (starting at 5-10 mg/hr IV or 120 mg daily oral dose) with careful monitoring of blood pressure and heart function. Diltiazem requires dose adjustment in renal failure as it is partially eliminated by the kidneys, and hemodialysis does not significantly remove the drug. More importantly, diltiazem has negative inotropic effects that can worsen heart failure, particularly in patients with reduced ejection fraction. If diltiazem is deemed necessary, close monitoring of vital signs, volume status, and cardiac function is essential. Alternative rate control strategies such as amiodarone or digoxin may be considered in this complex patient population when beta-blockers are contraindicated or ineffective, as suggested by the 2019 ACC/AHA versus ESC guidelines on heart failure 1. Key considerations include:

• The potential for diltiazem to exacerbate heart failure due to its negative inotropic effects
• The need for dose adjustment in patients with renal failure
• The importance of close monitoring of patients on diltiazem, especially those with reduced ejection fraction
• The consideration of alternative rate control strategies when beta-blockers are not suitable. The most recent and highest quality study, the 2019 ACC/AHA versus ESC guidelines on heart failure 1, supports the use of beta-blockers as the first-line rate-control medication, with digoxin as an adjunctive medication, and recommends caution with the use of non-dihydropyridine calcium antagonists such as diltiazem in patients with heart failure with reduced ejection fraction (HFrEF).

From the FDA Drug Label

Diltiazem slows the ventricular rate in patients with a rapid ventricular response during atrial fibrillation or atrial flutter The use of diltiazem hydrochloride injection or diltiazem hydrochloride for injection should be undertaken with caution when the patient is compromised hemodynamically or is taking other drugs that decrease any or all of the following: peripheral resistance, myocardial filling, myocardial contractility, or electrical impulse propagation in the myocardium In patients with cardiovascular disease, diltiazem hydrochloride injection administered intravenously in single bolus doses, followed in some cases by a continuous infusion, reduced blood pressure, systemic vascular resistance, the rate-pressure product, and coronary vascular resistance and increased coronary blood flow In a limited number of studies of patients with compromised myocardium (severe congestive heart failure, acute myocardial infarction, hypertrophic cardiomyopathy), administration of intravenous diltiazem produced no significant effect on contractility, left ventricular end diastolic pressure, or pulmonary capillary wedge pressure

Key Considerations:

• Atrial Fibrillation with RVR: Diltiazem can be used to slow the ventricular rate in patients with atrial fibrillation or atrial flutter.
• Hemodialysis: There is no direct information in the provided drug labels regarding the use of diltiazem in patients undergoing hemodialysis.
• CHF: Diltiazem should be used with caution in patients with compromised hemodynamics, including those with congestive heart failure (CHF).
• Clinical Decision: Given the presence of CHF, caution should be exercised when administering diltiazem to a patient with atrial fibrillation and rapid ventricular response (RVR) who is also undergoing hemodialysis. The patient's hemodynamic status should be closely monitored. 2 2

From the Research

Patient Considerations

• The patient has atrial fibrillation (AFib) with rapid ventricular response (RVR) and is undergoing hemodialysis with congestive heart failure (CHF).
• The question is whether Cardizem (diltiazem) can be given to this patient.

Medication Considerations

• Diltiazem is a calcium channel blocker that can be used for rate control in AFib with RVR 3, 4, 5, 6, 7.
• However, in patients with CHF, diltiazem may have negative inotropic effects, which could worsen heart failure symptoms 5, 6.

Study Findings

• A study comparing metoprolol and diltiazem for AFib with RVR found that metoprolol was associated with a lower risk of adverse events, but diltiazem was more effective in reducing heart rate 3.
• Another study found that prehospital administration of diltiazem for AFib with RVR was safe and effective when strict protocols were followed 4.
• A study comparing diltiazem and metoprolol in patients with AFib and CHF found that diltiazem reduced heart rate more quickly and effectively, but with no difference in safety outcomes 5.
• However, another study found that diltiazem was associated with a higher incidence of worsening heart failure symptoms in patients with CHF and AFib 6.

Key Points

• Diltiazem can be used for rate control in AFib with RVR, but its use in patients with CHF requires caution due to potential negative inotropic effects.
• The decision to use diltiazem in this patient should be made on a case-by-case basis, taking into account the patient's individual characteristics and medical history.
• Close monitoring of the patient's heart rate, blood pressure, and heart failure symptoms is necessary when using diltiazem in this context.