Congestive Heart Failure Flashcards
What is congestive heart failure?
What are the two main causes of congestive heart failure?
Inadequate pumping and/or filling of the heart caused by interference with the normal mechanisms regulating cardiac output
Two main causes:
- Hypertension
- Coronary Artery Disease
What are the risk factors for congestive heart failure?
Diabetes
Smoking
Obesity
Age
High cholesterol
What affects cardiac output?
Preload - The volume of blood in the ventricles at the end of diastole
Afterload - The peripheral resistance which the ventricle has to pump against
Myocardial contractility - The contraction of the ventricles resulting in ejection of blood
Heart rate - The rate at which the heart is contracting
What is systolic failure?
The inability of the heart to contract and pump blood effectively, caused by impaired contractility of the left ventricle
What is diastolic failure?
The inability of the ventricles to relax and fill during diastole (e.g. in atrial fibrillation)
How does the sympathetic nervous system compensate for a failing heart?
SNS senses low cardiac output and increases contractility, heart rate and peripheral vasoconstriction
How does the endocrine system compensate for a failing heart?
Low cardiac output triggers the RAAS, increasing cardiac workload, myocardial dysfunction and ventricular remodelling
What is ventricular dilation?
Stretching of the ventricle in response to high blood pressure. This temporarily increases cardiac output but over time the stretched ventricle results in a decreased contractile force and cardiac output
What is ventricular hypertrophy?
Thickening of myocardium triggered by overwork and strain, resulting in reduced stroke volume due to thickening of the myocardium
What are the symptoms of congestive heart failure?
Fatigue - Trouble perfusing body
Shortness of breath - Especially in left-sided heart failure, due to a backlog of fluid in the lungs
Arrhythmia - Stretching of the conduction system in the heart
Cyanosis - Poor oxygenation of tissues due to a backlog of fluid in the lungs
Peripheral oedema - Especially in right-sided heart failure, due to a backlog of fluid in the body
Nocturia - Bloodflow distributed to other areas of the body during the day and only to kidneys mainly at night
Weight gain - Fluid retention, kg/day, due to inadequate pumping
Orthopnea - Difficulty breathing while lying flat due to fluid pooling in the lungs
What are some diagnostic tests for congestive heart failure?
Physical assessment
X-Ray
- Detect fluid in lungs
- Heart should be 1/3 size of chest
Echocardiogram
- Differentiate ventricular hypertrophy and dilatation
Blood tests (not necessarily needed if X-ray and/or echocardiogram are done)
What are the goals for the management of congestive heart failure?
Improving heart function
Improving exercise tolerance
Symptom relief
Reduce hospital admissions
What are some strategies for the management of congestive heart failure?
Fluid balance monitoring/restriction
Daily weighs
Low sodium diet
Health promotion
- Medication adherence
- Promoting increasing exercise tolerance
What are some medications/surgical interventions to manage/treat congestive heart failure?
Diuretics - decrease peripheral and pleural oedema
ACE-inhibitors - Recuce remodelling and hypertension and inhibit RAAS
Beta-blockers - Reduce workload on the heart by reducing heart rate & hypertension
Antiarrhythmics
Anticoagulants
Positive inotropes - Improve contractility
LVAD - A surgically implanted mechanical device to pump the blood
Heart transplant - The only “cure” for congestive heart failure
