Heart Failure Flashcards
(44 cards)
What is heart failure?
A complex clinical syndrome caused by a structural or functional abnormality in the cardiac muscle that impairs its ability to function as a pump and meet the metabolic needs of the body.
What happens when the body senses inadequate organ perfusion in heart failure?
It activates multiple systemic neuro-hormonal pathways which initially compensate by redistributing blood flow to vital organs but later exacerbate symptoms and lead to clinical deterioration.
How does the incidence of congestive heart failure (CCF) change with age?
The incidence of CCF increases with age. More common in > 60yrs
How can heart failure be classified anatomically?
Into right sided heart failure, left sided heart failure, and biventricular heart failure.
How can heart failure be classified functionally? By ejection fraction
Into heart failure with reduced ejection fraction (systolic heart failure), EF <40%
heart failure with preserved ejection fraction (diastolic heart failure) =>50%, and
Mildly reduced EF 41-49%
What are the most common causes of heart failure?
- Ischemic heart disease (35-40%)
- Cardiomyopathies (Dilated) (30-34%)
- Hypertensive heart disease (15-20%)
Others:
Hypertrophic and restrictive cardiomyopathies
* Valvular heart lesions (mitral, aortic, tricuspid)
* Congenital heart disease (ASD, VSD)
* Alcohol and drugs (chemotherapy- doxorubicin)
* Hyperdynamic state (anemia, thyrotoxicosis, hemochromatosis, Paget’s disease)
* Right ventricular heart failure (RV infarct, pulmonary hypertension, pulmonary embolism, COPD)
* Tricuspid incompetence
* Pericardial disease (constrictive pericarditis, pericardial effusions)
What defines heart failure with reduced ejection fraction (HFrEF)?
Left ventricular ejection fraction <40%.
Also known as Systolic sheart failure or left ventricular systolic dysfunction (LVSD).
What are common causes of heart failure with reduced ejection fraction?
- Ischemic heart disease (IHD)/Myocardial infarction
- Hypertension
- Diabetes usually via IHD
- Valve disease
- Arrhythmias
- Drugs or alcohol
What characterizes systolic heart failure?
There is reduced cardiac contractility.
What are manifestations of systolic heart failure?
- Weakness
- Fatigue
- Reduced exercise tolerance
- Symptoms of hypoperfusion
What defines heart failure with preserved ejection fraction (HFpEF)?
Left ventricular relaxation failure leads to inadequate filling, decreasing stroke volume but maintaining normal ejection fraction (≥50%).
Also known as Diastolics heart failure.
What are common causes of heart failure with preserved ejection fraction?
- Hypertension
- Diabetes
- Constrictive pericarditis
- Cardiac tamponade
- Restrictive cardiomyopathy
Which gender is more affected by heart failure with preserved ejection fraction?
Much more common in women than men, especially elderly women with hypertension.
What is a common cause of right ventricular systolic dysfunction?
Cor pulmonale: primary lung disease (e.g COPD) causing vasoconstriction in poorly ventilated lung tissue to correct the decreased V/Q (ventilation perfusion ratio) leading to pulmonary hypertension and RVF
LVF due to pulmonary HTN causing RVF
Pulmonary valve stenosis
Pulmonary embolism
What defines high output heart failure?
Normal heart but increased needs due to conditions such as anemia, beri beri, large AV fistula, pregnancy, and hyperthyroidism.
What are precipitating causes of heart failure?
- H-Hypertension (systemic)
- E-Endocarditis (infection)
- A-Anemia
- R-Rheumatic fever and myocarditis
- T-Thyrotoxicosis and pregnancy
- F-Fevers (infections)
- A-Arrhythmias
- I-Infarction (myocardial)
- L-Lung infection
- E-Embolism (pulmonary)
- S-Stress (emotional, physical, environment, dietary, fluid excess)
What compensatory mechanisms does the heart depend on to maintain its pumping function ?
- Intrinsic mechanism
1. Frank-Starling mechanism: An increase in venous return or end-diastolic volume results in an increase in stroke volume and cardiac output.
2. myocardial hypertrophy: increase in muscle mass helps maintain cardiac performance - Extrinsic mechanism
1. baroreceptor reflex : increases release of catechcolamines, activation of RAAS and other neurohormonal adjustments
2. renin-angiotensin-aldosterone system : It is activated to correct poor perfusion to the kidneys due to decreased cardiac output.
What happens to the sympathetic nervous system in heart failure?
Its activity is elevated to compensate for decreased cardiac output.
What is the effect of vasoconstriction in heart failure?
It increases afterload, which reduces ejection fraction and cardiac output.
What triggers myocardial remodeling in heart failure?
Increased stress on the ventricular chamber walls.
What is the New York Heart Association classification for heart failure?
Class I - No limitation in physical activity. Normal physical exercise does not cause fatigue, dyspnea or palpitations.
Class II - Mild limitation of physical activity. Comfortable at rest but normal physical activity produces fatigue, shortness of breath, or palpitations.
Class III - Marked limitation of activity. Comfortable at rest but gentle exertion causes marked symptoms of heart failure.
Class IV - Symptoms of heart failure occur at rest and are exacerbated by any physical activity
What are common signs and symptoms of congestive heart failure?
- Exertional dyspnea
- Orthopnea
- Paroxysmal nocturnal dyspnea
- Fatigue
- Signs: cardiomegaly, S3 & S4 heart sounds, elevated JVP, tachycardia, hypotension, bi-basal crepitations, pleural effusion, peripheral ankle edema, ascites, tender hepatomegaly
What is used to diagnose heart failure?
- Blood
- FBC : anemia may mimic or exacerbate symptoms
- U/E and LFTs
- thyroid function tests : thurotoxicosis can cause high output failure while hypothyroidism may cause symptoms of fatigue and edema
Troponin - Imaging
* Chest X-ray
* Echocardiography
* ECG
What are criteria for validating congestive heart failure according to Framingham criteria?
MAJOR
* Paroxysmal nocturnal dyspnea or orthopnea
* Elevated JVP
* Pulmonary rales
* S3
* Cardiomegaly on chest X-ray
MINOR
- Peripheral edema
- Nighttime cough
- Dyspnea on exertion (DOE)
- Pleural effusions
- HR > 120
- Weight loss > 4.5 kg in 5 days with diuresis
