Clayton's Basic Pharmacology

Heart Failure Flashcards

Heart Failure (HF)

A condition where the heart cannot pump enough blood to meet the body's needs, leading to decreased tissue perfusion and fluid overload.

HFrEF

Heart Failure with Reduced Ejection Fraction

HFpEF

Heart Failure with Preserved Ejection Fraction

Causes of HFrEF

Myocardial damage (e.g., MI), cardiomyopathy, dysrhythmias.

Causes of HFpEF

Left ventricle becomes stiff and fails to relax, reducing ventricular filling. Causes include hypertension, aortic stenosis, and hypertrophy.

Three main compensatory mechanisms in heart failure

Sympathetic Nervous System, RAAS Activation, Vasopressin Release

Role of natriuretic peptides (BNP, ANP) in HF

They counteract volume overload by promoting diuresis and vasodilation.

SIX Cardinal sign of heart failure

dyspnea, chest pain, fatigue,edema,syncope,palptations

Lab findings suggest HF

BNP > 100 pg/mL, NT-proBNP > 300 pg/mL, Hyponatremia (<130 mEq/L), Elevated serum creatinine

ACCF/AHA Stage classifications

Patient has structural heart disease with past or current symptoms of HF.

A	At risk for heart failure, but no structural disease or symptoms	- Hypertension, diabetes, obesity, metabolic syndrome, family history of cardiomyopathy - No current structural changes or symptoms
B	Structural heart disease but no symptoms of HF	- Previous MI, LV remodeling (e.g., LV hypertrophy or low EF) - Valvular disease, but no signs/symptoms of HF
C	Structural heart disease with prior or current symptoms of HF	- Shortness of breath, fatigue, reduced exercise tolerance - Known structural heart abnormalities like decreased EF
D	Refractory (end-stage) HF requiring specialized interventions	- Symptoms at rest - Recurrent hospitalizations - Requires advanced therapies (e.g., heart transplant, mechanical support)

The ACCF/AHA Stage classifications of heart failure categorize patients based on the presence of symptoms and structural heart disease. They range from Stage A, where patients are at risk without structural disease, to Stage D, which indicates refractory heart failure necessitating specialized interventions.

NYHA Classifications

Marked limitation of physical activity; symptoms occur with less-than-ordinary activity, but patient is comfortable at rest.

Class	Description	Functional Capacity
Class I	No limitation of physical activity	- Ordinary activity does not cause fatigue, palpitation, dyspnea
Class II	Slight limitation of physical activity	- Comfortable at rest - Ordinary activity causes fatigue, dyspnea, etc.
Class III	Marked limitation of physical activity	- Comfortable at rest - Less-than-ordinary activity causes symptoms
Class IV	Unable to carry on any physical activity without discomfort	- Symptoms may be present even at rest - Any activity increases discomfort

The New York Heart Association (NYHA) classifications assess the impact of heart failure on physical activity levels. They include four classes ranging from Class I, which indicates no limitations, to Class IV, indicating severe limitations with symptoms at rest.

Main action of digoxin in HF

Increases myocardial contraction (positive inotropy) and slows heart rate (negative chronotropy) -> improves cardiac output.

How ACE inhibitors work in HF

Reduce preload and afterload by inhibiting vasoconstriction and aldosterone secretion -> improves cardiac output and tissue perfusion.

Entresto (valsartan-sacubitril)

Combines ARB and neprilysin inhibitor to reduce afterload/preload, increase natriuretic peptides -> improves cardiac output and lowers mortality.

Role of beta blockers in HF

Inhibit sympathetic activity, reduce HR and renin release -> lower morbidity and mortality.

Main benefit of nitrates in HF

Vasodilation -> reduces preload and afterload, relieving congestion and improving tissue perfusion.

Early signs of digoxin toxicity

Anorexia, nausea, visual disturbances, fatigue, bradycardia

Factors increasing risk for digoxin toxicity

Hypokalemia, renal impairment, elderly patients

Antidote for severe digoxin toxicity

Digoxin immune fab (Digibind)

What to assess before giving digoxin

Apical pulse for 1 minute - Hold if <60 bpm; check potassium level.

Why daily weights are important in HF

Best indicator of fluid gain/loss; a gain of 2 lbs in 2 days should be reported.

Patient education for HF self-care

Monitor weight and symptoms, adhere to medications, follow a low-sodium diet, know when to seek help.

Nurse's role in managing fluid restrictions

Divide fluids through the day, encourage tracking intake, and teach patient strategies to stay within limits.

Effects of the Sympathetic Nervous System in HF

Increased heart rate, vasoconstriction

Effects of RAAS activation in HF

Increased sodium and water retention