Cardiac failure (acute and chronic) Flashcards
What is the generic defintion of cardiac failure?
The Failure of the heart to maintain the cardiac output (CO) needed to meet the body’s requirements
CO = HR x SV
What is chronic HF?
Chronic Heart Failure: A long-term condition in which the heart fails to maintain an adequate circulation for the needs of the body.
What are some features of chronic HF?
Ø Develops and progresses slowly
Ø Can have periods of acute decompensation
What is acute HF?
Rapid onset or worsening of symptoms & signs of HF, requiring urgent Tx and evaluation.
What is low output HF?
CO is ↓ and fails to increase normally with exertion
What is high output HF?
CO is normal but you have ↑ needs (e.g. hyperthyroidism, pregnancy).
Heart failure occurs when the heart fails to meet those increased needs (the heart is overworked).
What is congestive HF?
When LHF and RHF occur simultaneously
What is the major sign of congestive HF?
- breathless (sign of LVF) &
- oedema (sign of RHF)
due to abnormal salt and water retention
What are the 3 major causes & examples of LHF?
1)Valvular:
- ØAortic stenosis,
- ØAortic Regurgitation
- ØMitral Regurgitation
2) Heart Muscle:
- ØIschaemic Heart Disease
- Cardiomyopathy
- Myocarditis
- Arrhythmias (AF)
3) Systemic:
- Ø Hypertension,
- Ø Amyloidosis
- Ø Drugs (e.g. cocaine, alcohol, BBs*, chemotherapeutics - eg doxorubicin)
Why does aortic stenosis cause LHF?
causes excessive afterload.
Basically the ventricle has to push harder to eject blood from a stenosed aortic valve.
(NB: afterload = the pressure the heart must work against to eject blood during systole)
Why does aortic regurgitation cause LHF?
There is increased pressure in the LV due to the regurgitant blood form the aorta to the LV
(the LV in addition to having to pump the normal volume of blood, has to pump the regurgitant blood as well).
These changes lead to cardiac remodeling (dilatation, hypertrophy) leading to heart failure.
Why does mitral regurgitation cause LHF?
If significant (moderate to severe) MR is present, the Left Ventricle must work harder to keep up with the body’s demands for oxygenated blood.
Over time, the heart muscle and circulatory system undergo a series of changes to maintain this increased demand – due to mechanical overload the LV overtime can become, hypertrophied, fibrotic, dilated and scarred, ending up with an impaired myocardial function.
This can lead to LHF (mitral regurgitation increases preload)
Why does HTN cause LHF?
increases afterload.
LV has to push harder in order to push blood against high systemic pressures.
This over time puts strain in the LV leading to LHF.
Why does amyloidosis cause LHF?
In amyloidosis, an abnormal protein called amyloid builds-up in tissues and organs.
If amyloid gets deposited in the heart, the heart becomes increasingly stiff and eventually the pumping function deteriorates.
Give examples of drugs that can cause LHF
- cocaine
- alcohol,
- chemo,
- betablockers (negative chrono & ino tropic effect)
As beta blockers used to be contraindicated in HF, which ones are now recommended?
- metoprolol succinate
- bisoprolol,
- carvedilol
What are the most serious cardiac side effects of beta blockers?
- symptomatic hypotension
- unacceptable fatigue
- exacerbation of heart failure in patients with acute decompensated heart failure
What are some non-cardiac side effects of beta blockers?
- depression
- fatigue
- dizziness
- bradycardia
- sexual dysfunction
What are the 3 main causes & examples of RHF?
1) LHF
2) Lungs:
- Ø Pulmonary HTN (can lead to cor pulmonale)
- Ø PE
- ØChronic Lung Disease (interstitial lung disease, pulmonary fibrosis, cystic fibrosis)
3) Heart valves:
- ØTR
- Ø Pulmonary valve Disease e.g. Pulmonary stenosis or Pulmonary regurg.
What is cor pulmonale?
Enlargement and failure of RV due to increased pressure in the lungs/vascular resistance
Why does pulmonary HTN cause RHF?
heart cannot pump to the stiffened pulmonary arterial vessels. So RV needs to work harder, becomes enlarged and weakened
Why does chronic lung disease cause RHF?
can result in chronic hypoxia:
- The pulmonary vasculature results to chronic hypoxia by vasoconstriction.
- This increases vascular resistance and and results in increased pulmonary arterial pressure.
- The right heart reacts to this by remodeling (hypertrophy and dilatation).
- Over time it can lead to RHF.
Why does tricuspid regurgitation cause
Why does TR cause RHF?
increases preload –>
mechanical overload the RV can become, hypertrophied, fibrotic, dilated and scarred, ending up with an impaired myocardial function.
This can lead to LHF (mitral regurgitation increases preload)
Why does pulmonary stenosis cause LHF?
causes excessive afterload.
the ventricle has to push harder to eject blood from a stenosed pulmonary valve.
(NB: afterload = the pressure the heart must work against to eject blood during systole)
Why does pulmonary regurgitation RHF?
There is increased pressure in the RV due to the regurgitant blood from the pulmonary artery to the RV (the RV in addition to having to pump the normal volume of blood, has to pump the regurgitant blood as well).
These changes lead to cardiac remodeling (dilatation, hypertrophy) leading to heart failure.
What is the acronym for the causes of high output HF & what does it stand for?
NAP MEALS
- Nutritional (B1: thiamine)
- Anaemia
- Pregnancy
- Malignancy (multiple myeloma)
- Endocrine (hyperthyroidism)
- AV malformations
- Liver cirrhosis
- Sepsis
Symptoms of which type of LH presents first in high output HF?
RHF symptoms & signs, then LHF
What are the group of symtoms seen in LHF?
respiratory symptoms due to fluid accumulation in the lungs
e.g. pulmonary oedema
What is the cause of symptoms seen in RHF, and what is it complicated by?
Symptoms of fluid congestion in the system (esp. periphery) due to the backpressure in the venous system
Complicated by:
- salt & water retention due to activation of RAS by renal hypoperfusion and SNS activation.
- Initially RAS and SNS activation initially improve CO, by increasing water retention,
- but later on they propagate the heart failure syndrome.
Nme the symptoms of LHF
- ØExertional dyspnea
- ØOrthopnoea (SOB when lying flat)
- ØParoxysmal nocturnal dyspnea – PND (attacks of SOB at night)
- ØFatigue
- ØNocturnal Cough (+/- pink frothy
- sputum)
- ØWheeze
Explain the NYHA stages of dyspnoea
Class I: no symptoms
Class II: Symptoms on exertion
Class III: symptoms on minimal exertion
Class IV: symptoms at rest
What are the signs of LHF?
Heart
- ↑HR, ↑RR
- Irregularly Irregular heart beat
- Pulsus alternans
- Displaced apex beat
- S3 Gallop rhythm
- S4 in severe HF
- Murmur (AS, MR, AR)
Lungs
- Fine end-inspiratory crackles at lung bases (bibasilar) (pulmonary oedema)
- Wheeze (cardiac asthma)
What is cardiac asthma?
medical diagnosis of wheezing, coughing or shortness of breath due to congestive heart failure.
It is known as cardiac asthma because the symptoms mimic ordinary asthma (bronchial asthma)
What is the cause of S3 in LHF?
S3: is due to rapid ventricular filling and volume overload –so it makes sense to have that in HF. S3 in general is an indication of ventricular dysfunction
What is the cause of S4 in LHF?
S4: due to poor compliance of the ventricle – compliance against a stiff ventricle
Name the symptoms of RHF
- Swelling (ankles, facial engorgement, ascites)
- Weight gain (due to oedema)
- Fatigue
- Reduced exercise tolerance
- Anorexia
- Nausea
- Nocturia
What is the cause of nocturia in RHF?
as fluid returns from the legs when patient lies down
Name the signs of RHF
- Face: face swelling
- Neck: ↑JVP
- Heart/Chest: TR murmur, ↑HR, ↑RR
- Abdomen: Ascites, hepatomegaly
- Other: pitting oedema in ankles & sacrum
Name 3 causes of a raised JVP
1) RHF
2) Tricuspid regurg
3) Constrictive pericarditis
A 70 years old lady presents with dyspnoea, which has becoming worse over the last months. She also reports cough, productive of pink frothy sputum. On examination her pulse is irregularly irregular, and she has a high respiratory and heart rate. What is the most likely diagnosis?
A.Acute Coronary Syndrome
B.Aortic stenosis
C.Congestive Heart Failure
D.Right Heart Failure
E.Left Heart Failure
E.Left Heart Failure
What are some possible
a) Bedside
b) Bloods
c) Imaging
investigations for ?HF
a) bedside: ECG
b) Bloods: FBC, U&Es, LFTs, TFTs, BNP (sensitive but non-specific)
c) Imaging: CXT, TTE
What is BNP?
- BNP (=Brain natriuretic peptide) is a a hormone secreted by cardiomyocytes in the heart muscles in response to stretching caused by increased ventricular volume.
- Its physiologic effects include reduction in renal sodium reabsorption, which in turn lead to reduction in circulating blood volume.
What is a disadvantage of BNP?
What is the main use of BNP?
Not sensitive, can be raised in a variety of conditions e.g. PE, COPD
Main use = to exclude HF (if negative)
Why is
a) FBC
b) LFT
c) TFT
conducted for ?HF
FBC: anaemia and high lymphocyte counts are strong RF and prognostic factors of poor survival.
LFTs: check for abdo congestion
TFTs: check for hypo/hyperthyroidism
If BNP was raised in a ?HF pt, what is the nect step?
TTE
Transthoracic echocardiogram coupled with doppler
(diagnostic)
What is the use of a TTE?
- May indicate cause (MI, valvular disease)
- Can calculate ejection fraction (EF) = % of the blood present in the LV which is pumped during systole (Normal EF= 50-70%)
i. e. helps to differentiate between HFrEF and HFpEF
What is the definition of HFrEF?
EF < 40%: HF with reduced ejection fraction
Indicates inability of the ventricle to contract normally
What is the definition of HFpEF?
EF >50%: HF with preserved ejection fraction
Indicates inability of the ventricle to relax and fill normally
Name some features of HF on an CXR
-
Alveolar oedema
- batwing appearance (this is fluid inside the interstitium of the lung)
-
B-lines (kerley)
- due to interstitial oedema- accumulation of fluid along interlobular septa
-
Cardiomegaly
- cardiothoracic ration > 50%)
-
Dilated upper lobe vessels
- indicate pulmonary venous HTN. It is thought to be bc perivascular oedema causes increased resistance at the lung bases and inverts the normal perfusion gradient such that upper lobe blood flow exceeds lower lobe flow.
-
Effusion (pleural, transudative)
- (indicated by blunting of the costophrenic angle) – this is fluid outside the lung (cf pulm oedema) and happens after pulmonary oedema (fluid first accumulates inside the lungs and then moves outside)
a) What is the Framingham criteria?
b) name some of the major & minor criteria
a) set of criteria required for a clinical diagnosis of HF, requires 2+ major, OR 1 major and 2 minor
b) see image
What is the conservative management of HF?
- smoking cessation,
- weight management (exercise),
- diet (reduce salt intake )
What is the available medical Tx for HF?
- ACE inhibitors (enalapril): should be given to ALL pts with LV dysfunction as it improves survival and slows down progression.
- BBs (carvedilol, bisoprolol): reduce O2 demand on the heart. All patients with CHF should receive a BB once established on an ACEi – improve survival & synergistic effects with ACEi.
- Diuretics (furosemide, chlorothiazide, spironolactone): use if evidence of fluid retention, monitor electrolytes (spironolactone can cause hyperkalaemia)
- Digoxin: +inotrope (increases heart contractility), helps improve symptoms but does NOT increase overall survival.
- Other: hydralazine nitrate, cardiac resynchronization, implantable cardiac defibrillator TREAT THE CAUSE
If there is evidence of fluid retention, why are loop diuretics preferred over dieuretics?
Loop dieretics e.g. frusemide act more proximally and are hence more effective
What is the most common cause of new onset acute HF?
acute coronary syndrome
What are some common causes of acute HF?
1) Decompensation of previous chronic HF
2) Acute Coronary Syndrome
Name some factors that contribute to acute decompensation (causing acute HF)
- MI
- Arrhythmias
- Infection
- Hypo/hyperthyroidism
- Uncontrolled HTN
What symptoms/signs would be seen on a Hx for ?acute HF
- ØDyspnoea
- ØCough
- ØWheeze
- ØPink frothy sputum
- ØSwelling of the legs
- ØSymptoms of the underlying condition
What signs would be seen o/e for ?acute HF
Ø↑HR, ↑RR
ØPulsus alternans
ØCyanosis
ØPeripheral shutdown
ØS3 gallop rhythm
ØFine end inspiratory crackles
Explain the management of acute HF
1st secure ABC
- Sit patient up
- High-glow Oxygen via non rebreathe mask (Target SpO2 = 94-98%)
- Furosemide 40-80mg IV (then monitor U&Es as can cause hypokalaemia)
- (GTN infusion evidence of pulmonary oedema AND SBP > 90mmHg)
- Consider CPAP (if sats are dropping)
- Treat cardiogenic shock if BP < 90mmHg with positive inotropes (e.g. dobutamine)
Name some complications of HF
ØPleural effusion
ØRenal failure (long standing HF can lead to hypoperfusion)
ØAcute exacerbations
ØDeath
A 67-year-old woman presents to her GP complaining of increasing shortness of breath, which becomes worse when trying to sleep. She has a history of hypertension and hyperlipidaemia. On examination, her blood pressure is 148/83 mmHg and heart rate is 126 beats per minute. There is an audible S3 gallop and the jugular venous pressure is elevated 3 cm above normal.
Which investigation would be best to confirm the diagnosis?
A.ECG
B.Brain natriuretic peptide (BNP)
C.Endothelin levels
D.Echocardiogram
E.CXR
D: echo
A 62 year old man, 3 months after an MI presents with increasing shortness of breath. He is currently on aspirin, atenolol and simvastatin. An echocardiogram shows an ejection fraction of 30% in the left ventricle. What additional medication should he be given?
A.Carvedilol
B.Furosemide
C.Digoxin
D.Enalapril
E.Morphine
D.Enalapril
