Heart Failure, Oedema and Infective Endocarditis Flashcards
What is heart failure?
A condition caused by cardiac dysfunction and resulting in dyspnoea, fatigue and the inability to do exercise
How can heart failure diagnosis be made with confidence?
Clinical history/exam
+ evidence of cardiac dysfunction
(+ response to diuretics)
What examinations should be carried out to assess cardiac dysfunction in heart failure?
Echocardiogram
Ventriculogram
Cardiac MRI
Radionuclide imaging
What are some potential causes of heart failure?
Many severe structural diseases: LV systolic/diastolic dysfunction RV failure Valve disease Myocarditis Pericardial restriction Restrictive cardiomyopathy Arrhythmias
What tests should be done to screen for heart failure?
12 lead ECG
Blood test for BNP levels
With that investigations can LV dysfunction be diagnosed?
Thorough history ECG CXR Echo CT/coronary angiogram Blood tests (FBC, U&E, glucose, BNP)
What can cause LV systolic dysfunction?
Dilated cardiomyopathy
Infarction (MI)
Severe valve disease
bacterial/viral infections Toxins IVDA Systemic diseases Hypertension
What is the prognosis for heart failure?
Poor, only 58% are alive within 5 years.
30-40% mortality at 1 year
How is heart failure classified?
Depending on severity of symptoms. Worse prognosis for worse stage
What is the common treatment for heart failure?
Diuretics
ACE inhibitors (or ARB’s)
Beta blockers
Aldosterone receptor blockers
What are some common symptoms of heart failure?
Shortness of breath (rest/exertion) Fatigue Inability to do exercise Leg swelling Orthopnea/PND
What are some signs of heart failure?
Tachycardia Raised JVP Crackles on auscultation Displaced apex beat Third heart sound
What is the prevalence of heart failure?
Affects 1-2% of the population in the UK
Are heart failure patients likely to be readmitted after an emergency admission?
Yes, most likely in the first 3 months
What is Sympson’s biplane rule?
A measure for calculating LV ejection fraction from an echocardiogram
How can LVEF be measured in heart failure patients?
Echocardiogram
MUGA (ventriculogram)
Cardiac MRI
What are the main risk factors for heart failure?
Hypertension IHD (coronary disease) Alcohol Diabetes Valve disease Congenital defects Viral infections
What is the main system involved in heart failure, and what are its implications?
RAAS system
It’s activated by the reduction in LV ejection fraction causing lower cardiac output
This causes water/salt retention to increase BP and blood volume, which in turn puts more strain on the heart
What is the number one risk factor for heart failure?
Hypertension
What are the aims of heart failure treatment?
Improve survival
Reduce symptoms
What are the main therapeutic options in heart failure to reduce detrimental neurohormonal effects (RAAS activation)?
ACEi (ramipril)
ARB (valsartan)
Beta blockers (bisoprolol)
What are the main therapeutic options in heart failure to improve beneficial neurohormonal effects (ANP/BNP)?
ARNI’s (valsartan+sacubitril)
Neprolysin (sacubitril)
Why should ANP/BNP be stimulated in heart failure?
Because it promotes water and salt excretion and vasodilation
Opposite effect of RAAS
Why should the RAAS be inhibited in heart failure?
Because it causes a reaction to the reduced cardiac output which causes higher blood volume (higher preload) and puts even more strain on the heart
What are the main therapeutic options in heart failure to reduce symptoms?
Diuretics (furosemide +/- thiazides)
What are the main therapeutic options in heart failure to improve the contractility of the heart?
Positive inotropes: Digoxin
Isorbate mononitrate or dinitrate
Ivabradine: slows heart rate (only give if BPM>70)
When should beta blockers be given to a patient with heart failure?
Once/if they are stable. Don’t give in acute circumstances as their sympathetic drive is the only thing keeping them alive
What are some disadvantages of using diuretics in heart failure?
Can cause: hypotension Low K+ and Na+ Dehydration Gout Increased levels of other drugs in the body (toxicity)
What types drugs should be closely monitored when putting a patient with heart failure on diuretics? Give some examples
Narrow therapeutic index drugs: Gentamicin/vancomycin Lithium NSAIDs Digoxin
What are some disadvantages of ACEi in heart failure?
Doesn’t block alternative angiotensin pathways
Can cause: First dose hypotension Angioedema (afrocaribbeans) Cough Hypotension Kidney damage
What drug-drug interaction is important when giving elderly patients ACEi?
NSAIDs
What other way can angiotensin I be converted into angiotensin II?
Chymase pathway
Which receptor is blocked by angiotensin receptor blockers?
AT1
What are the main three physiological aims of heart failure treatment?
Decrease RAAS activation
Increase ANP/BNP action
Improve cardiac function
What is the combined action of ARNIs in heart failure?
Valsartan - stops angiotensin II conversion
Sacubitril - prevents ANP/BNP breakdown
Why would warfarin be given to heart failure patients?
To prevent clots forming in dilated LV from the ineffective pumping of blood out of the heart
What are risk factors for native valve Infective endocarditis (IE)?
Rheumatic heart disease Mitral valve disease (prolapse) Degenerative heart disease Congenital heart disease Indwelling medical devices Alcoholism Diabetes IVDA Immunocompromised
What are the mechanisms of infection in IE?
Through mechanical damage -> exposure of extra cellular proteins -> inflammation (NBTE)
Inflammation -> integrins which bind to fibronectin on organism -> organism adheres to inflamed area
How would bacteria enter the bloodstream to adhere to the inflamed endocardium in IE?
Medical procedures
Dental procedures
Extra cardiac infections
Poor dental hygiene
What are some common symptoms of IE?
Fever
Weight loss, malaise, fatigue
Headache, arthalgia, weakness
What are some common signs of IE?
Skin lesions: Janeway lesions, Olsen nodes, cutaneous infarcts, petechial rash, septic emboli
Eyes: Roth spots
Nails: splinter haemorrhages
Neurological/meningeal signs
What investigations should be done to diagnose IE?
Blood cultures (3x, 30 mins apart) Blood test: FBC, CRP, ESR, U&E CXR Urinalysis echocardiogram PET or SPECT Cardiac MRI
What criteria are used for diagnosing IE?
Modified Duke criteria
What are the major criteria for IE diagnosis?
- Positive blood cultures (>2, 12 hours apart, causative organisms)
- Abnormal imaging tests
What are some of the causative agents for IE?
Strep viridans Strep bovis Enterococci Staph aureus Coxiella Burnetii Fungi HACEK gram -ve group
What is the treatment of IE?
IV antibiotics
Ampicillin/flucloxacillin
Gentamicin/vancomycin
Rifampicin
What complications could arise from IE and may call for surgery?
Heart failure
Uncontrolled infection
Risk of systemic embolisation (PE, CVA)
What are possible prevention methods for IE?
- Prophylactic antibiotics for high risk patients during high risk procedures
- Effective dental hygiene/check ups
- infection control
- aseptic techniques
What are the minor Duke criteria for IE diagnosis?
- Predisposing factors
- Fever
- Vascular signs
- Immunological signs
- Microbiological evidence
What is the prevalence of IE?
3-10 in 100,000 people
Men > women
Women worse prognosis
