Will Cardene (Nicardipine) Drip Lower Heart Rate?
No, Cardene (nicardipine) drip will not lower heart rate—it typically increases heart rate as a reflex response to vasodilation and blood pressure reduction. 1
Mechanism and Hemodynamic Effects
Nicardipine is a dihydropyridine calcium channel blocker that works by selectively relaxing vascular smooth muscle, producing significant decreases in systemic vascular resistance without directly affecting cardiac conduction or contractility 1. The drug's effects are more selective to vascular smooth muscle than cardiac muscle 1.
The increase in heart rate is a normal physiological response to vasodilation and decreased blood pressure 1. When nicardipine causes peripheral vasodilation and blood pressure drops, the body's baroreceptor reflex triggers compensatory tachycardia to maintain cardiac output 2.
Expected Heart Rate Changes
In placebo-controlled trials, nicardipine produced mean heart rate increases of:
While nicardipine may increase heart rate acutely, some studies suggest that tachycardia does not persist during long-term oral therapy 2. However, for IV infusions used in acute settings, the reflex tachycardia remains a consistent finding 3.
Clinical Implications for Cardiovascular Patients
In Coronary Artery Disease
In patients with coronary disease, it is prudent to avoid tachycardia when lowering blood pressure 4. The European Society of Cardiology guidelines emphasize that blood pressure should be lowered gradually in coronary patients and tachycardia should be avoided 4.
Nicardipine's tendency to increase heart rate may be problematic in patients with:
- Active coronary ischemia (increased myocardial oxygen demand) 4
- Recent myocardial infarction 4
- Unstable angina 4
Combination with Beta-Blockers
The combined use of nicardipine with beta-blockers may be beneficial, as beta-blockers can prevent the reflex tachycardia induced by nicardipine's vasodilation, while nicardipine prevents the increase in peripheral vascular resistance that occurs during beta blockade 2.
Electrophysiologic Properties
Nicardipine has no negative effect on cardiac conduction at therapeutic doses 1. During acute electrophysiologic studies, nicardipine:
- Increased heart rate 1
- Prolonged the corrected QT interval to a minor degree 1
- Did not affect sinus node recovery or SA conduction times 1
- Did not prolong AV nodal conduction time 1
This distinguishes nicardipine from non-dihydropyridine calcium channel blockers (verapamil, diltiazem), which do slow heart rate and can cause bradyarrhythmias 4.
Practical Considerations
When Heart Rate Control is Needed
If heart rate reduction is a therapeutic goal (such as in atrial fibrillation, supraventricular tachycardia, or acute coronary syndromes), nicardipine is not the appropriate agent 4. Instead, consider:
- Beta-blockers (esmolol for acute IV control) 4
- Non-dihydropyridine calcium channel blockers (diltiazem or verapamil) 4
Monitoring During Nicardipine Infusion
Continuous heart rate monitoring is essential during nicardipine infusion 5, 6. Watch for:
- Pronounced tachycardia (some patients may develop marked increases) 1
- Signs of myocardial ischemia if heart rate increases significantly in patients with coronary disease 5
- Palpitations (a commonly reported adverse effect) 4
Special Populations
In patients with heart failure and preserved systolic function, nicardipine increased cardiac output and improved left ventricular function, but the heart rate increase was still observed 7. The drug should be used with caution in patients with severe left ventricular dysfunction, as it may have a negative inotropic effect 1.