Heart Failure V: Medical Management

Medical Management of Acute Decompensated Heart Failure (ADHF)

The primary goals of therapy for patients hospitalized with acute decompensated heart failure (ADHF) include:

• Relieving symptoms
• Optimizing volume status
• Supporting oxygenation and ventilation
• Maintaining cardiac output (CO) and end-organ perfusion
• Identifying and addressing the cause of ADHF
• Preventing complications
• Providing patient education on factors precipitating HF exacerbation
• Planning for discharge

Ongoing monitoring and assessment are crucial. Stable patients may be treated in the emergency department or admitted to a telemetry unit, assessed at least every four hours. For dyspnea relief, positioning the patient in a high-Fowler's position helps. Also, the body weight, intake, and output should be monitored. Unstable patients require intensive care unit (ICU) admission, where continuous electrocardiogram (ECG) and oxygen (O2) saturation monitoring, along with hourly assessments of vital signs and urine output, are necessary. Hemodynamic monitoring may be employed to adjust therapies to maximize CO and reduce pulmonary artery wedge pressure (PAWP), including arterial blood pressure and pulmonary artery pressures.

Supplemental oxygen is provided to increase the partial pressure of oxygen (PaO2). Noninvasive positive pressure ventilation (e.g., bilevel positive airway pressure [BiPAP]) or mechanical ventilation may be necessary for severe pulmonary edema.

Pharmacological Management:

• Diuretics are first-line treatments for volume overload, reducing preload and improving left ventricular (LV) function. Examples include intravenous (IV) loop diuretics like furosemide.
• Vasodilators: Intravenous (IV) nitroglycerin and sodium nitroprusside help reduce pre- and afterload.
• Morphine: Morphine relaxes pulmonary and systemic blood vessels, reducing preload and afterload. It is administered in small IV boluses to relieve dyspnea, with close monitoring for respiratory depression.
• Positive Inotropes: Beta (β)-agonists (e.g., dopamine, dobutamine) and phosphodiesterase inhibitors (milrinone) increase myocardial contractility and are used in patients with low cardiac output.

Interprofessional Care: Chronic Heart Failure

Chronic heart failure (HF) therapies are tailored to the patient's co-morbid conditions, aiming to manage symptoms, reduce mortality and morbidity, and minimize side effects. These therapies address the underlying cause, enhance cardiac output (CO), improve ventricular function and quality of life (QOL), and preserve organ function.

Supplemental Oxygen: In HF, reduced blood oxygenation can decrease oxygen saturation (O2). Supplemental oxygen improves saturation, meets tissue oxygen needs, and alleviates dyspnea and fatigue. Ongoing pulse oximetry assesses the need for and effectiveness of oxygen therapy.

Physical and Emotional Rest: Conserves energy and reduces oxygen demand.

Angiotensin-converting enzyme (ACE) Inhibitors: ACE inhibitors are the recommended first-line medications for treating heart failure with reduced ejection fraction (HFrEF). They reduce symptoms by inhibiting the conversion of angiotensin I into angiotensin II, reducing afterload and systemic vascular resistance (SVR), and slowing ventricular remodeling.

Angiotensin II Receptor Blockers (ARBs): These are recommended for patients intolerant to ACE inhibitors. They prevent the effects of angiotensin II, promoting afterload reduction and vasodilation.

Neprilysin-Angiotensin Receptor Inhibitors: Sacubitril/valsartan (Entresto) combines neprilysin inhibition and ARB effects, reducing SVR, afterload, and central venous pressure (CVP) while increasing natriuresis and diuresis.

Aldosterone Antagonists: Spironolactone (Aldactone) and eplerenone (Inspra) are potassium-sparing diuretics that inhibit aldosterone, providing a mild diuretic effect.

Ivabradine: Selectively inhibits the sodium or potassium current in the sinoatrial (SA) node, reducing heart rate. It is beneficial for patients with HFrEF who are in sinus rhythm with a heart rate of at least 70 beats per minute (bpm) and have persistent symptoms despite other medications.

Hydralazine/Isosorbide Dinitrate Combination (Bidil): Effective in patients with HFrEF, combining two vasodilators for those already on optimal doses of other medications.

Digitalis (Digoxin) is a weak positive inotrope that acts as a neurohormonal modulator, reducing the renin secretion and the effects on the sympathetic nervous system.

Dapagliflozin (Farxiga) is a sodium-glucose co-transporter 2 (SGLT-2) inhibitor that lowers the risk of cardiovascular (CV) death and hospitalization in patients with HFrEF.

Diuretics: These drugs reduce fluid overload symptoms in both types of heart failure, such as HFrEF and HFpEF, by promoting sodium and water excretion. Loop diuretics (for example, furosemide and bumetanide) act on the ascending loop of Henle to facilitate this excretion, reducing edema, pulmonary venous pressure, and preload.