Heart Failure: A Case Study

1. What are the compensatory mechanisms that occur when a patient has heart failure?

Sympathetic nervous stimulation: This compensatory mechanism is the first one. Epinephrine (adrenaline) and norepinephrine (noradrenaline) are released which causes an increase in BP and the heart to pump faster and more powerfully. They also increase cardiac output in this way it temporally helps compensate for the hearts reduced ability to pump blood. This is not good long term as it increased the amount of oxygen the myocardium needs.

Renin angiotensin system activation: Because of decreased blood flow to the kidneys the compensatory mechanisms activate to hold on to sodium and water. When the Blood flow is decreased Angiotensin II is released causing vasoconstriction

and aldosterone secretion causes the kidneys to hold on to sodium and water which increases preload and afterload. It causes the blood pressure and heart rate to increase temporally helping the heart pump better, long term can cause contractile dysfunction due to ventricular remodeling.

Other chemical responses: due to low cardiac output the pituitary gland releases antidiuretic hormone (ADH) this hormone results in vasoconstriction and retention of fluid which temporally helps, but soon leads to worsening of heart failure due to fluid overload and rapid heart rate.

Myocardial hypertrophy: Because the heart is trying to pump blood more efficiently (overuse of the muscle) the walls of the heart thicken in order to make more muscle mass this causes more forceful muscle contraction which increases cardiac output.

This also caused an increase in demand of oxygen to the cardiac muscle so it’s not a good thing (Ignatavicius &Workman, 2013, p. 747).

2. What are 3 things that can worsen heart failure and why?

High sodium diet: Too much sodium causes fluid retention which increases the workload of the heart. The reason sodium causes water retention is because water moves from low concentrations to high concentrations. Water follows salt so when too much salt is consumed it draws the water from the blood into the tissue.

Not taking the prescribed medication: Medications are prescribed to decrease the workload of the heart, prevent fluid retention and decrease the amount of harmful hormones that are released. When the patient fails to comply with prescribed medications all these things are not managed.

Not staying active: Because it has been proven that activity can help with weight loss, lower blood pressure, reduce LDL cholesterol and increase HDL cholesterol, all of these can decrease the workload of the

heart.

3. Give 2 arrhythmias that could occur with heart failure, why do they occur and what is the treatment?
Atrium fibrillation (AF): Can occur if rapid, disorganized electrical signals cause the atria to contract too fast and irregularly. This can happen in heart failure patients because of damage to the heart. During AF blood pools in the atria it isn’t properly pumped into the ventricle As a result the chambers don't work together as they should. Since these patients are at risk for thromboembolisms they are put on an anticoagulant such as heparin or Lovonox to prevent it. Calcium channel blockers to slow the heart rate such as Diltiazem or Amiodarone. Beta blockers such as metoprolol or esmolol may be used to slow ventricular response. Digoxin may also be given. When drugs are not working cardioversion is performed (Ignatavicius &Workman, p. 722, 727).

Ventricular tachycardia (VT): is defined as a pulse of more than 100 beats per minute and at least three irregular beats in a row.

It occurs because of repetitive electrical activity. This can occur in a patient with early or late heart failure, because there is damage to the heart tissue and the heart beats faster to try to supply the body with blood. Recommended treatment is elective cardioversion. Drugs used include an antidysrhythmic such as Mexitil or Sotalol (Ignatavicius &Workman, p. 728-729).

4. What are the primary assessments for a patient in heart failure?

A cardiac assessment: Listen to heart sounds listening for extra heart sounds, fast heartbeat, and monitor EKG looking for dysthymias. Assess vitals especially BP, BP should be kept low in heart failure patients to put less stress on the heart. Assess the patient for edema as a result of fluid retention. Listen for crackles in the lungs due to fluid built up. Watch I&O’s and weight the patient to assess for edema, ask about activity intolerance. Assess for changes in mental status, cool extremities, pale or cyanotic, fatigue, and JVD (Indications of poor perfusion) (Ignatavicius &Workman, p.756).

5. What is the primary nursing diagnosis for this

patient
Decreased cardiac output r/t impaired cardiac function