Heart failure treatment involves a range of medications beyond standard therapies. These adjunct drugs target different aspects of cardiac function, offering additional benefits for patients. From digoxin to vericiguat, each medication plays a unique role in managing heart failure symptoms and improving outcomes.

Understanding these adjunct therapies is crucial for nurses. They need to know how these drugs work, their side effects, and important nursing considerations. This knowledge enables better patient care, from monitoring vital signs to educating patients about their medications and potential complications.

Adjunct Medications in Heart Failure Treatment

Key adjunct medications for heart failure

• Digoxin
  • Cardiac glycoside medication used to treat heart failure and atrial fibrillation
  • Increases cardiac contractility by inhibiting the sodium-potassium ATPase pump, leading to increased intracellular calcium levels
  • Reduces heart rate through vagal stimulation, decreasing the workload on the heart (ivabradine)
• Hydralazine and isosorbide dinitrate combination
  • Vasodilator medications that work together to reduce cardiac workload and improve cardiac output
  • Hydralazine acts as an arterial vasodilator, reducing afterload on the heart (amlodipine)
  • Isosorbide dinitrate functions as a venous vasodilator, reducing preload on the heart (nitroglycerin)
• Ivabradine
  • Selective sinus node inhibitor that reduces heart rate without affecting cardiac contractility
  • Blocks hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in the sinoatrial node, slowing the heart rate
  • Useful in patients with heart failure who have elevated heart rates despite optimal beta-blocker therapy
• Vericiguat
  • Soluble guanylate cyclase stimulator that improves cardiac function and reduces the risk of hospitalization in heart failure patients
  • Enhances the production of cyclic guanosine monophosphate (cGMP), leading to vasodilation and reduced cardiac remodeling
  • Helps to alleviate symptoms and improve exercise tolerance in patients with worsening chronic heart failure (sacubitril/valsartan)

Additional key medications for heart failure

• Angiotensin-converting enzyme (ACE) inhibitors
  • Reduce the production of angiotensin II, leading to vasodilation and decreased workload on the heart
  • Improve survival and reduce hospitalizations in heart failure patients
• Beta-blockers
  • Slow heart rate and reduce the heart's workload, improving left ventricular function over time
  • Particularly beneficial in patients with reduced ejection fraction
• Diuretics
  • Help manage fluid overload by increasing urine output and reducing congestion
  • Improve symptoms such as shortness of breath and edema
• Aldosterone antagonists
  • Block the effects of aldosterone, reducing fluid retention and improving cardiac remodeling
  • Particularly useful in patients with severe heart failure or post-myocardial infarction
• Natriuretic peptides
  • Used as biomarkers to diagnose and monitor heart failure progression
  • Elevated levels indicate increased cardiac stress and may guide treatment decisions

Mechanisms of adjunct heart failure drugs

• Digoxin
  • Inhibits the sodium-potassium ATPase pump, leading to increased intracellular sodium and calcium levels
  • Higher intracellular calcium concentrations enhance cardiac contractility by facilitating stronger myocardial contractions
  • Vagal stimulation by digoxin slows the heart rate, reducing the metabolic demands on the heart
• Hydralazine and isosorbide dinitrate
  • Hydralazine dilates arteries by relaxing smooth muscle cells, reducing peripheral resistance and afterload on the heart
  • Isosorbide dinitrate dilates veins by releasing nitric oxide, increasing venous capacitance and reducing preload on the heart
  • The combination of reduced preload and afterload improves cardiac output and decreases the workload on the failing heart
• Ivabradine
  • Blocks HCN channels in the sinoatrial node, which are responsible for the spontaneous depolarization of pacemaker cells
  • Selective reduction of heart rate without affecting cardiac contractility or blood pressure
  • Particularly beneficial in heart failure patients with elevated heart rates who cannot tolerate higher doses of beta-blockers
• Vericiguat
  • Stimulates soluble guanylate cyclase, an enzyme that catalyzes the conversion of guanosine triphosphate (GTP) to cGMP
  • Increased cGMP levels promote vasodilation, reduce vascular resistance, and decrease cardiac remodeling
  • Improves cardiac function, reduces symptoms, and decreases the risk of hospitalization in patients with worsening chronic heart failure

Side effects of adjunct heart failure medications

• Digoxin
  • Nausea, vomiting, and loss of appetite due to gastrointestinal irritation
  • Visual disturbances, such as blurred vision or yellow-green halos around objects
  • Arrhythmias, particularly in the setting of digoxin toxicity or electrolyte imbalances (hypokalemia)
  • Confusion, disorientation, and delirium, especially in older patients or those with renal impairment
• Hydralazine and isosorbide dinitrate
  • Headache, dizziness, and lightheadedness due to vasodilation and potential hypotension
  • Tachycardia as a compensatory response to reduced blood pressure
  • Flushing, skin rash, and itching as a result of histamine release
• Ivabradine
  • Bradycardia, particularly in patients with pre-existing conduction disorders or those taking other heart rate-lowering medications
  • Visual disturbances, such as luminous phenomena (phosphenes) or blurred vision
  • Atrial fibrillation, which may paradoxically increase heart rate and reduce the effectiveness of ivabradine
• Vericiguat
  • Hypotension, especially when combined with other vasodilators or antihypertensive medications
  • Headache and dizziness related to vasodilation and reduced blood pressure
  • Anemia due to the potential for decreased erythropoiesis and hemoglobin levels

Nursing considerations for adjunct therapies

• Digoxin
  • Monitor serum digoxin levels regularly to ensure therapeutic concentrations and avoid toxicity
  • Assess electrolyte levels, particularly potassium, as hypokalemia can increase the risk of digoxin toxicity
  • Educate patients on the signs and symptoms of digoxin toxicity and the importance of regular follow-up visits
• Hydralazine and isosorbide dinitrate
  • Monitor blood pressure and heart rate closely, especially during dose titration and when combining with other vasodilators
  • Educate patients on proper medication administration, including taking isosorbide dinitrate on an empty stomach and avoiding abrupt discontinuation
  • Instruct patients to report any persistent or severe side effects, such as headache or dizziness
• Ivabradine
  • Assess heart rate and rhythm regularly, particularly in patients with a history of conduction disorders or bradycardia
  • Educate patients on the importance of reporting any visual disturbances or signs of excessive bradycardia
  • Monitor for the development of atrial fibrillation, which may require additional treatment or modification of ivabradine therapy
• Vericiguat
  • Monitor blood pressure closely, especially when initiating therapy or adjusting doses
  • Assess hemoglobin levels periodically to detect and manage potential anemia
  • Educate patients on the signs and symptoms of hypotension and anemia, and encourage them to report any concerns
• General considerations for all adjunct therapies
  • Assess medication adherence and provide strategies to improve compliance, such as pill organizers or reminder systems
  • Encourage lifestyle modifications, including salt restriction, physical activity, and stress management, to optimize heart failure management
  • Reinforce the importance of regular follow-up appointments and prompt reporting of any changes in symptoms or overall health status
  • Regularly assess the patient's New York Heart Association (NYHA) functional classification to monitor disease progression and guide treatment adjustments