Cardiology Flashcards
What is heart failure?
The heart is unable to pump enough blood to meet the demands of the body
How do you calculate cardiac output?
HEART RATE x STROKE VOLUME = CARDIAC OUTPUT
What types of heart failure are there?
- Systolic
- Diastolic
What is meant by systolic heart failure?
Inability of the heart muscle to contract forcefully enough during systole
Reduced ejection fraction (< 40%)
What is meant by diastolic heart failure?
Inability of the heart muscle to fill with blood adequately during diastole
Normal ejection fraction
What are the causes of systolic heart failure?
- Ischaemic heart disease
- Cardiomyocyte damage/death due to ischaemia means heart muscle cannot contract as forcefully. - Long-standing hypertension:
- LV has to contract more forcefully against a higher pressure, which results in LV hypertrophy. LV hypertrophy increases number of cardiomyocytes (increasing oxygen demand) and squeezes the coronary arteries (reducing oxygen supply). Increased demand for oxygen and reduced supply means that the heart muscle cannot contract as forcefully. - Dilated cardiomyopathy:
- LV wall is thinner so cannot contract as forcefully. - Congenital heart disease, e.g. ASD, VSD
- This will cause a left to right shunt, which increases the blood volume in the RV. RV contracts more forcefully, causing RV hypertrophy and right-sided HF (explanation - see number 2)
What are the causes of diastolic heart failure?
- Long-standing hypertension:
- LV has to contract more forcefully against a higher pressure, which results in LV hypertrophy. LV hypertrophy means there is less space in chamber to fill with blood. - Aortic stenosis:
- LV has to contract more forcefully against a higher pressure, which results in LV hypertrophy. LV hypertrophy means there is less space in chamber to fill with blood. - Hypertrophic/restrictive cardiomyopathy:
- Hypertrophy cardiomyopathy causes LV hypertrophy. LV hypertrophy means there is less space in chamber to fill with blood.
- Restrictive cardiomyopathy = ventricular wall is stiffer and less compliant, so cannot stretch/allow ventricle to fill with blood adequately. - Congenital heart disease, e.g. ASD, VSD
- This will cause a left to right shunt, which increases the blood volume in the RV. RV contracts more forcefully, causing RV hypertrophy and right-sided HF as there is less space in the chamber to fill with blood.
What is the main complication of left-sided heart failure? What are the symptoms and signs of this complication?
Give some other signs of left-sided heart failure.
Pulmonary oedema:
- Symptoms: dyspnoea, orthopnoea, paroxysmal nocturnal dyspnoea, fatigue
- Signs: crepitations
Other signs:
- Cardiomegaly (displaced apex beat)
- 3rd and 4th heart sounds
What is cor pulmonale?
Cor pulmonale is right-sided heart failure caused by chronic lung disease, e.g. COPD.
In chronic lung disease, there is hypoxaemia which results in pulmonary vasoconstriction. This vasoconstriction increases pulmonary BP. Increased pulmonary BP means that the RV must contract more forcefully against a higher pressure, which causes RV hypertrophy and right-sided heart failure (systolic and diastolic).
What is the main complication of right-sided heart failure?
What are the signs of this complication?
Systemic congestion/oedema:
- Jugular venous distension
- Ascites
- Hepatosplenomegaly
- Sacral/pedal oedema
Describe the investigation of heart failure
CXR: characteristic changes! A - alveolar oedema B - Kerley B lines C - cardiomegaly D - dilated, prominent upper lobe vessels E - pleural Effusion
Bloods:
- B type natriuretic peptide
- FBC (anaemia exacerbates HF), LFTs (check for damage due to hepatomegaly/cirrhosis), U&Es (as a baseline before starting pharmacological therapy)
ECG:
- May show underlying cause, e.g. ischaemia, LV hypertrophy
Echo:
- To assess ventricular systolic and diastolic function
Describe the pharmacological management of heart failure
ABCD:
A - ACE-i / ARB (if ACE-i is contraindicated)
B - Beta blocker
C - CCB
D - Diuretics (loop diuretic, aldosterone antagonist)
a) In clinic, what blood pressure reading is indicative of hypertension?
b) Which follow up investigation should be carried out to confirm the diagnosis of hypertension? How are the results of this investigation interpreted?
c) What other investigations should be performed once hypertension has been diagnosed?
a) BP > 140/90 mmHg is INDICATIVE of hypertension
b) Follow up investigation: ABPM (ambulatory blood pressure monitoring) or HBPM (home blood pressure monitoring)
A diagnosis of hypertension is made in patients with:
- A clinic BP reading of > 140/90 mmHg AND
- A HBPM/ABPM reading of > 135/85 mmHg
c) Checking for end-organ damage:
- Urine analysis, e.g. checking kidney function
- Fundoscopy, e.g. checking for hypertensive retinopathy
- ECG, e.g. checking for LV hypertrophy
It is also important to do a QRISK2 assessment
What are the causes of hypertension?
Primary (essential) hypertension
Secondary hypertension
Give some risk factors for developing primary (essential) hypertension
- Smoking
- Obesity
- Sedentary lifestyle
- Diet high in salt
- High alcohol intake
- High demand, low control jobs (stress)
- Genetics
- Age
Give some causes of secondary hypertension
- Renal disease, e.g. CKD
- Endocrine conditions, e.g. acromegaly, Conn’s syndrome
- Pregnancy
Describe the conservative management of hypertension
- Smoking cessation
- Weight control
- Encourage exercise
- Reduce salt/alcohol intake
Describe the pharmacological management of hypertension
Over 55 years old / Afro-Caribbean?
If answer is NO…
- A
- A + C
- A + C + D
- A+ B + C + D
if answer is YES…
- C
- A + C
- A + C + D
- A + B+ C + D
Key: A = ACE-i / ARB (if ACEi is contraindicated) B = beta blocker C = calcium channel blocker D = thiazide diuretic
Give 2 examples of an ACE inhibitor
Ramipril
Lisinopril
Give 2 examples of an ARB
Losartan
Candesartan
Give 3 examples of beta blockers
Atenolol
Bisoprolol
Propanolol
Give 2 examples of calcium channel blockers
Amlodipine
Nifedipine
Give an example of a loop diuretic
Furosemide
Give an example of a thiazide-like diuretic
Bendroflumethiazide
Give an example of an aldosterone antagonist
Spironolactone
What are the symptoms of stable angina?
CHEST PAIN
- Central, crushing, retrosternal chest pain
- Exacerbated by exercise
- Relived by rest
- Pain may radiate to left arm, neck or jaw
Other symptoms:
- Dyspnoea
- Palpitations
- Sweating
- Nausea
Describe the investigation of stable angina
ECG:
- Usually normal
- May show ST depression/T wave inversion
CXR:
Checking heart size and pulmonary vessels
CT angiography is diagnostic - coronary artery stenosis
Describe the conservative management of stable angina
- Smoking cessation
- Weight loss
- Exercise
- Monitor diet
Describe the pharmacological management of stable angina
Symptomatic relief for angina attacks:
- GTN spray
Preventing angina attacks:
- Beta blocker or CCB
Secondary prevention of CVD (4 A’s):
- Aspirin (and clopidogrel)
- Atorvastatin (statin)
- ACE inhibitor
- Atenolol (beta blocker) - if not already on one
Describe the interventional management of angina
- PCI (percutaneous coronary intervention)
- CABG (coronary artery bypass graft)
What is meant by the term ‘acute coronary syndromes’?
Umbrella term:
- Unstable angina
- STEMI
- NSTEMI
What is unstable angina?
Chest pain occurring on minimal exertion/at rest
Give an example of a rare type of angina and describe its pathology
Prinzmetal’s angina - transient ischaemia caused by coronary artery spasm
What is the difference between a STEMI and an NSTEMI? Describe their pathophysiology.
STEMI: is complete occlusion of a MAJOR coronary artery by a thrombus, causing full thickness damage of the heart muscle
NSTEMI: is complete occlusion of a MINOR coronary artery or partial occlusion of a MAJOR coronary artery, causing partial-thickness damage to the heart muscle
Describe the common pathology of all ACS
- Rupture of fibrous cap of atheroma
- Platelet aggregation, adhesion and local thrombus formation
- Distal thrombus embolisation in coronary artery
Describe the symptoms of ACS
CHEST PAIN:
- Central, crushing, retrosternal chest pain
- Pain may radiate to left arm, jaw or neck
- Pain not relieved by GTN spray/rest
Other symptoms:
- Dyspnoea
- Palpitations
- Sweating
- Nausea
Describe the initial investigations/management of a patient presenting to A+E with suspected ACS
Initial Ix:
- Bloods: Troponin T (to be measured again 12 hours after onset of symptoms)
- ECG
Initial management: MOAN
- Morphine
- Oxygen
- Aspirin 300 mg and clopidogrel
- Nitrates - GTN spray
How would the results of the initial investigations allow you to differentiate between STEMI/NSTEMI/unstable angina?
STEMI: ECG shows persistent ST elevation and troponin will show a significant RISE or FALL after 12 hours
NSTEMI: ECG may be normal or may show some ST depression/T wave inversion, and troponin T will show either a significant RISE or FALL after 12 hours
Unstable angina: ECG may be normal or may show some ST depression/T wave inversion, but troponin T levels will be NORMAL
Following the initial management for a patient presenting with a suspected ACS, describe the definitive management if ECG shows features associated with STEMI.
If patient has presented within 90 MINUTES of onset of symptoms: reperfusion therapy (percutaneous coronary intervention - PCI)
If patient has presented more than 90 minutes after the onset of symptoms: thrombolysis (IV alteplase)
Describe the pharmacological and interventional management of a NSTEMI/unstable angina
Pharmacological - 4A’s (secondary prevention of CVD):
- Aspirin (and clopidogrel)
- Atorvastatin (statin)
- ACE inhibitor/ARB
- Atenolol (beta blocker)
Interventional:
- PCI or CABG
What is meant by coarctation of the aorta?
Narrowing of the aorta at the site of the ductus arteriosus
