Chronic Heart Failure (CHF) Flashcards
(66 cards)
Define heart failure
Syndrome that occurs when the heart is unable to pump sufficient blood to meet the metabolic demands of the body
Characterized by dyspnea and abnormal retention of water and sodium
What changes can cause heart failure?
- Preload
- Afterload
- Contractility
- Heart rate
Define preload
- Stretching of muscle fibers in (L) ventricle @ end of diastole
- Affected by systemic BP & rate of venous return
Define Afterload
- Amount of pressure (L) ventricle must work against to pump blood into circulation
Define contractility
Ability of muscle cells to contract after depolarization
Define EDV
- Volume in ventricle during diastole
2. Approx 110-120 ml
Define stroke volume
- Volume of blood that empties out of ventricle during systole
- Approx 70 ml
Define ESV
- Remaining volume in each ventricle after systole
2. Approx 40-50 ml
Define Ejection fraction
- End diastolic volume that is ejected
2. Approx 60%
What demographic group has heart failure?
Primarily a disease of elderly
75% of cases occur in pts > 65 yrs of age
What is the etiology of CHF?
1. Abnormal cardiac function A. MI B. Cardiomyopathy C. Cardiac arrhythmia 2. Abnormal left ventricular volume A. Diseases with high metabolic rate -Anemia -Hyperthyroidism - Pregnancy 3. Abnormal ventricular pressure A. HTN B. Pulmonary HTN C. COPD D. Aortic or pulmonic valve stenosis 4. Abnormal ventricular filling A. Mitral / tricuspid stenosis B. Atrial fibrillation C. HTN
Define Class I heart failure
Patients withcardiac disease butresulting in no limitation of physical activity. Ordinary physical activity does not cause undue fatigue, palpitation, dyspnea or anginal pain.
Define Class II heart failure
Patients with cardiac disease resulting in slight limitation of physical activity. They are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnea or anginal pain.
Define Class III heart failure
Patients with cardiac disease resulting in marked limitation of physical activity. They are comfortable at rest. Less than ordinary activity causes fatigue, palpitation, dyspnea or anginal pain. t
Define Class IV heart failure
Patients with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms of heart failure or the anginal syndrome may be present even at rest. If any physical activity is undertaken, discomfort increases.
Hwo can heart failure be classified?
Sides or cardiac cycle involved
Define right sided heart failure
Right sided heart failure (Cor Pulmonale)
Usually 2° to left sided heart failure
Also occurs 2° to COPD & Pulm HTN
What is the most common cause of systolic heart failure?
Most common cause is ischemic heart disease
What is the most common cause of diastolic heart failure?
Most common cause is HTN
What is Stage A of heart failure?
- No objective evidence of CV disease. No symptoms and no limitation in ordinary physical activity.
- High risk for HF but without structural heart disease or sx’s of HF
A. HTN, Ischemic heart disease
What is stage B of Heart failure?
- Objective evidence of minimal cardiovascular disease. Mild symptoms and slight limitation during ordinary activity. Comfortable at rest.
- Structural heart disease but without signs/sx’s of HF
A. Previous MI, LVH, asymptomatic valvular disease
What is stage c of Heart failure?
- Objective evidence of moderately severe cardiovascular disease. Marked limitation in activity due to symptoms, even during less-than-ordinary activity. Comfortable only at rest.
- Structural heart disease with prior or current sx’s of HF
What is stage D of heart failure?
- Objective evidence of severe cardiovascular disease. Severe limitations. Experiences symptoms even while at rest.
- Refractory HF requiring specialized interventions
What is the pathophys of left sided heart failure?
- ↓ Contractility of left ventricle
2. Leads to dec CO -> blood backs up into left atrium and then into lungs -> Pulmonary edema