Heart Failure as a drug target Flashcards
What is heart failure and how is it different from a heart attack or cardiac arrest?
Heart failure is the inability of the heart to pump blood effectively around the body. It is not a heart attack, cardiac arrest, or a sign of imminent death. Many people live for years with heart failure.
What is the typical prevalence of heart failure in the UK and at what age is it commonly diagnosed?
The prevalence of heart failure in the UK is 2%, and it is correlated with age. The average age at diagnosis is 77.
What are the common causes of heart failure?
Common causes of heart failure include ischaemic heart disease, hypertension, valve disease (where the heart valves don’t fully open or close), cardiomyopathy (disease of the heart muscle), and arrhythmias (problems with heart rhythm).
What is the difference between right-sided heart failure and left-sided heart failure?
Right Sided Heart Failure: Results in fluid buildup in the body, especially in the legs (peripheral oedema), causing swelling, pain, difficulty walking, skin infections, tiredness, light-headedness, and fainting.
Left Sided Heart Failure: Results in fluid buildup in the lungs (pulmonary oedema), causing crackly breathing, breathlessness (especially on exertion or lying flat), cough with pink sputum, tiredness, light-headedness, and fainting.
What is congestive cardiac failure?
Congestive cardiac failure is the failure of both sides of the heart. When one side fails, the other side takes on more work, eventually leading to failure of both sides.
What investigations are commonly used to measure heart failure?
Important investigations include:
Brain Natriuretic Peptide (BNP): A hormone secreted by heart muscle cells in response to stretching, correlated with increased blood volume.
Echocardiogram: An ultrasound of the heart to assess structure, size, function, and ejection fraction.
Symptom Burden: Measured using the New York Heart Association (NYHA) classification.
What factors influence the prognosis of heart failure?
Prognosis is based on factors such as demographics, symptoms, comorbidities (e.g., hypertension), objective clinical parameters (e.g., ejection fraction, BNP levels), and the NYHA classification. Only 65% of patients in NYHA class 4 survive after a mean follow-up of 17 months.
How does preload relate to heart failure and how can it be managed?
Preload refers to the amount of stretch on cardiac muscle after diastole, or the volume of blood in the ventricle. It can be reduced using loop diuretics like furosemide and aldosterone antagonists like spironolactone. These medications reduce fluid buildup but come with risks like acute kidney injury and electrolyte imbalances.
What is afterload and how can it be reduced in heart failure?
Afterload is the pressure the heart must pump against, often represented by blood pressure in the aorta. It can be reduced using ACE inhibitors like ramipril, which lower blood pressure and reduce the heart’s workload, improving symptoms and survival.
How do beta blockers help in heart failure management?
Beta blockers (e.g., bisoprolol) reduce heart rate and help the heart pump more effectively. They improve long-term symptoms and survival but may worsen symptoms in the acute setting, especially if there is fluid overload.
What is the role of SGLT2 inhibitors in heart failure treatment?
SGLT2 inhibitors, like dapagliflozin, improve glycemic control, reduce blood pressure, and promote weight loss. They may also provide benefits in heart failure through mechanisms like natriuresis, improved renal function, and cardiac remodelling. However, risks include hypoglycemia, urinary tract infections, and polyuria.
What is the difference between prognostic and symptomatic benefits in heart failure treatment?
Prognostic Benefit: Improves survival and reduces mortality (e.g., ACE inhibitors, beta blockers, mineralocorticoid antagonists).
Symptomatic Benefit: Improves symptoms such as peripheral oedema and breathlessness (e.g., loop diuretics, digoxin).
How is heart failure with preserved ejection fraction (HFpEF) treated?
There is no evidence that treatments improve mortality or morbidity in HFpEF. Treatment focuses on managing comorbidities like hypertension, coronary artery disease, diabetes, and hypercholesterolemia, as well as alleviating symptoms using loop diuretics, weight loss, and improving exercise capability.
What are the potential risks of using loop diuretics, like furosemide, to treat heart failure?
The potential risks of using loop diuretics include acute kidney injury and hypokalaemia (low potassium levels).
What is the primary role of aldosterone antagonists, such as spironolactone, in the treatment of heart failure?
Aldosterone antagonists, like spironolactone, reduce sodium reabsorption, improve symptoms, and help reduce hospitalizations and mortality in heart failure. However, they also carry the risks of acute kidney injury and hyperkalaemia (high potassium levels).
Why are ACE inhibitors, like ramipril, commonly used in heart failure treatment?
ACE inhibitors, such as ramipril, are used to reduce afterload by inhibiting the conversion of angiotensin I to angiotensin II, a vasoconstrictor. This improves symptoms, reduces hospitalizations, and lowers mortality in heart failure patients. They should be uptitrated to the maximally tolerated dose but carry risks like acute kidney injury and hyperkalaemia.
How does beta-blocker therapy affect heart failure symptoms in the long term versus the acute setting?
In the long term, beta-blockers (e.g., bisoprolol) improve heart failure symptoms and mortality by reducing heart rate and improving the heart’s pumping efficiency. However, in the acute setting, beta-blockers can worsen symptoms, particularly if there is fluid overload.
What is the role of digoxin in heart failure, and when might it be used?
Digoxin is used to improve the efficiency of the heart in cases of atrial fibrillation or other conduction problems. It is also used in conjunction with anticoagulation to manage atrial fibrillation, improving cardiac function.
What is the significance of BNP (Brain Natriuretic Peptide) levels in heart failure diagnosis?
BNP is a hormone secreted by cardiomyocytes in response to ventricular stretching, and its levels correlate with increased ventricular blood volume. Elevated BNP levels are often used as a biomarker to diagnose heart failure and assess its severity.
What are the common treatments for coronary artery disease in heart failure patients?
Treatments for coronary artery disease in heart failure patients include the use of stents and coronary artery bypass surgery (CABG) to improve blood flow to the heart muscle and alleviate symptoms.
