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Evolving role of calcium channel blockers in heart failure
1Division of Pharmacy Practice, School of Pharmacy, University of North Carolina, Chapel Hill 27599-7360, USA.
Insights
Calcium channel blockers show mixed results in heart failure treatment. While newer agents like amlodipine improve outcomes, older ones can worsen heart function and increase cardiac events.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Calcium channel blockers (CCBs) are theoretically beneficial for chronic systolic heart failure due to vasodilation, anti-ischemic effects, and improved diastolic function.
- However, first-generation CCBs (nifedipine, verapamil, diltiazem) can cause adverse hemodynamic effects and clinical deterioration in heart failure patients.
Purpose of the Study:
- To evaluate the efficacy and safety of different generations of calcium channel blockers in treating chronic systolic heart failure.
- To assess the impact of CCBs on cardiac events, left ventricular function, and neurohormonal systems.
Main Methods:
- Review of existing studies on first- and second-generation CCBs in patients with heart failure.
- Analysis of hemodynamic effects, clinical outcomes, exercise capacity, and mortality associated with CCB use.
Main Results:
- First-generation CCBs were associated with negative inotropic effects, neurohormonal activation, and increased cardiac events.
- Second-generation CCBs like felodipine showed no sympathetic or renin-angiotensin system activation but lacked significant clinical benefit.
- Amlodipine demonstrated improvements in exercise tolerance, reduced symptoms, and decreased norepinephrine levels, and reduced morbidity/mortality in specific heart failure populations.
Conclusions:
- First-generation CCBs are generally contraindicated in heart failure due to adverse effects.
- Amlodipine shows promise as a safe and effective treatment option for certain types of heart failure, including dilated cardiomyopathy.
Abstract:
Calcium channel blockers are theoretically effective in the treatment of chronic systolic heart failure because of their actions as arteriolar dilators, antiischemic agents, and relaxants of diastolic left ventricular function, and because they may prevent progression of myocardial dysfunction. The first-generation calcium channel blockers nifedipine, verapamil, and diltiazem cause hemodynamic and clinical deterioration and may increase the frequency of cardiac events in postmyocardial infarction patients with heart failure. These drugs depress left ventricular contractility in the short term, and can activate neurohormonal systems due to their hypotensive effects. The second-generation calcium channel blocker felodipine does not activate the sympathetic nervous and renin-angiotensin systems, but has no effect on exercise capacity or mortality. Amlodipine increases exercise time and reduces symptoms and plasma norepinephrine concentration in heart failure. It also reduces morbidity and mortality in New York Heart Association class i.v. patients with nonischemic dilated cardiomyopathy, and appears to be effective as primary therapy for patients with dilated cardiomyopathy.