Heart Failure Flashcards
Define Heart Failure
Inability of the heart to pump or supply enough blood. Either a SYSTOLIC (pump problem) or DIASTOLIC (filling problem) failure. Not a diagnosis, but a syndrome.
Define systolic heart failure
Contractility of the left ventricle is reduced, causing reduced stroke volume and reduced ejection fraction and high end diastolic pressure/volume
What is normal LVEF
> 50%
CO = HR X SV (~5L/min)
What are common causes of systolic heart failure?
Anything that causes poor contractility, such as:
- Ischemia (most common)
- Long standing hypertension
- Dilated cardiomyopathy (e.g. from alcohol, haemochromotosis)
Define diastolic heart failure
LV has reduced compliance so less blood returns to the heart, and end diastolic pressure is increased. However, ejection fraction is normal
What are the causes of diastolic heart failure?
Anything that reduces ventricular compliance or causes hypertrophy such as:
- Hypertension
- Aortic stenosis or other valvular disease
- Inherited hypertrophic cardiomyopathy
- Restrictive cardiomyopathies
- Left to right cardiac shunt (ASD/VSD)
- Tachycardias (e.g. AF, aneamia, thyrotoxicosis, steroid induced)
What are the common causes of RHF?
- Most commonly, LHF
- PAH
- Right to left cardiac shunt
- Pulmonary causes “Cor Pulmonale” such as COPD, emphysema, PE
What are the common symptoms of RHF ?
Venous congestion is the main issue causing peripheral odema, ascites, nausea and anorexia and facial engorgement.
What are the common symptoms of LHF?
Pulmonary odema is the main issue, and causes dyspnea (especially with exertion), poor exercise tolerance, orthopnea and PND. In advanced disease patients can have resting tachycardia, cool and pale extremities and unexplained fatigue due to poor tissue perfusion
What is cardiorenal syndrome?
- Reduced CO activates RAAS due to reduced blood flow to kidneys
- RASS causes retention of Na+ and H20 to help increase BV and increase end diastolic volume
- This leads to worsening pulmonary odema and peripheral pitting odema
What are some common exam findings in LEFT heart failure?
- Coarse crackles bibasally (not cleared by coughing)
- Peripheral odema
- Third heart sound S3 (“ventricular gallop”)
- In severe cases can develop pulsus alternans (alternating pulse pressures)
- Narrow pulse pressure
- Displaced apex beat
What are the common exam findings of RIGHT heart failure?
- Raised JVP
- Spleno/Hepatomegaly (from congestion)
- Pitting odema or ascites
What medications should be considered in HF patients?
TREAT UNDERLYING CAUSE FIRST! ACEi, ARB and aldosterone receptor antagonists (e.g. spironolactone) reduce mortality. Beta-blockers should be USED WITH CAUTION if decompensated as they are a negative ionotrope. Thiazide or loop diuretics only treat symptoms! Vasodilators (isosorbide) or inotropes (digoxin) used in severe cases.
What is the use of BNP in CHF?
- Hormone released from myocardium in response to stretch
- Diagnostic “rule out test” if <30pg/mL; very likely if >145pmol/L
- Can be used to assess response to treatment
What are the NYHA classifications?
Class 1: symptoms (SOB/angina/fatigue) with extreme exertion; does not limit physical activity
Class 2: symptoms with moderate exertion
Class 3: symptoms with minimal exertion
Class 4: symptoms at rest; greatly restricts physical activity