Agents for treating HF Flashcards
(139 cards)
What is Afterload?
The resistance from the arteries when the heart is trying to pump blood through them
What is Cardiac Output?
The amount of blood that is being pumped out by the heart.
What is Cardiomegaly
Enlarged heart
What is Cardiomyopathy?
A group of heart conditions that can lead to Cardiomegaly, Muscle failure or death
What is Dyspnea?
Difficulty breathing, usually paired with anxiety
What is Heart Failure?
When the heart has poor cardiac output. May be caused by various factors.
What is Hemoptysis?
Coughing up blood
What is Nocturia?
Needing to urinate during the night. In HF this is usually caused by gravity depending edema
What is Orthopnea?
Difficulty breathing when laying down. Patient usually needs to be propped up to a 45 degree angle, but this varies from person to person.
What is Positive inotropic?
Drugs that causes a strong muscle contraction.
What is Preload?
Blood that come back to the heart to be circulated again.
What is Pulmonary edema?
Fluid buildup in the lungs.
What is Tachypnea?
Fast shallow respirations.
Explain the 4 stages of congestive heart failure
Stage A. High risk of HF but no structural heart disease or symptoms.
Stage B. Structural heart disease but no signs or symptoms of heart failure (heart starts to enlarge)
Stage C. Structural heart disease with prior or current symptoms of HF. (heart is enlarged and patient is starting to experience fatigue, shortness of breath and/or fluid retention)
Stage D. Refractory HF requiring specialized interventions.(patient have all the above symptoms and symptoms are no longer responsive to treatment)
Explain the 4 classifications of heart failure
Class 1. No limitation of physical activity (able to function as normal).
Class 2. Slight limitation of physical activity ( start to have symptoms with average physical activity).
Class 3. Marked limitation of physical activity (comfortable at rest, but normal activities makes them experience symptoms).
Class 4. Unable to perform any physical activity without symptoms or symptoms at rest (having symptoms whether they are resting or not and any physical activity makes them feel short of breath or fatigued).
What are some causes of Congestive Heart Failure?
Coronary artery disease : There is plaque and cholesterol buildup in the heart, which inhibits enough blood and oxygen to the heart and the heart isn’t operating well. May lead to an MI.
Cardiomyopathy : structural muscular changes and less effective pumping of the heart.
Hypertension : Will lead to cardiomegaly if left untreated because the heart works against pressure.
Valvular Heart Disease : Valves may leak and then the heart is working twice as hard to pump the blood through.
What do we look for in the blood when we suspect that someone has had a heart attack?
Troponin. This is a substance that the heart muscles release when they are damaged due to lack of oxygen and a buildup of toxins.
Name 3 ways the body compensates for decreased cardiac output.
By sympathetic stimulation
Positive inotropic effect (heart beats harder) and by the release of renin.
What are the long term effects of the compensation mechanisms of decreased cardiac output?
Over time, compensation mechanisms increase the hearts workload and the muscles of the heart may stretch and/or thicken. This results in the chambers not being able to effectively pump blood which leads to increased heart failure.
When does compensation start?
When the heart begins to be less effective at getting the blood where it needs to go. This may be caused by conditions such as hypertension or coronary heart disease.
What happens when there is decreased blood flow to the kidneys?
The RAAS is activated. This increases blood pressure, output and aldosterone levels.
Aldosterone increases sodium reabsorption which will increase fluid volume in the body and excrete more potassium. Increased fluid volume will increase BP.
All of this is hard on our hearts.
What are some symptoms of CHF?
- Fluid retention : Pitting edema, tachypnea, jugular vein distension, splenomegaly and nocturia.
- Long term compensation will cause cardiomegaly, S3 sounds and tachycardia. Distal pulses may become weaker and hypoxic and patients may feel weak and fatigued.
What are the drug catergories used for treatment for CHF?
****Cardiotonic (inotropic) drugs: **
Cardiac glycosides -Digoxin
Phosphodiesterase Inhibitors - Milrinone
HCN Blocker - Hyperpolarization-activated cyclic nucleotide-gated - Ivabrandine
Combination drugs ( work on both the inotropic and the RAAS) :
*Angiotensin Receptor Neurolysin Inhibitor (ARNI) - Sacubitril/Valsartan
What lifespan considerations should be taken into account when it comes to Cardiotonic agents in children?
Digoxin may be given. but NOT Phosphodiesterase inhibitors due to unknown severity risk and high potential for adverse effects in children. HCN blockers may be used for stable heart failure in children 6 months +
Dosage should always be double checked by another nurse.
Signs of toxicity is nausea, vomiting, confusion, visual disturbance and arrythmias.