Cardiology Flashcards
What are the most common valves which need replacing?
The most common valves which need replacing are the aortic and mitral valve.
What are the two options for valve replacement?
Biological (Bioprosthetic) and mechanical
Biological is usually bovine or porcine in origin
What are the advantages and disadvantages of biological valves?
Major disadvantage is structural deterioration and calcification over time. Most older patients ( > 65 years for aortic valves and > 70 years for mitral valves) receive a bioprosthetic valve
Long-term anticoagulation not usually needed. Warfarin may be given for the first 3 months depending on patient factors. Low-dose aspirin is given long-term.
What are the advantages and disadvantages of mechanical valves?
Mechanical valves have a low failure rate
Major disadvantage is the increased risk of thrombosis meaning long-term anticoagulation is needed.
What ongoing anticoagulation management is used in mechanical valves?
Warfarin
Asprin- if ischaemic heart disease
Warfarin is still used in preference to DOACs for patients with mechanical heart valves
Following the 2017 European Society of Cardiology guidelines, aspirin is only normally given in addition if there is an additional indication, e.g. ischaemic heart disease.
Target INR
aortic: 3.0
mitral: 3.5
What ongoing anticoagulation management is used in biological valves?
Long-term anticoagulation not usually needed. Warfarin may be given for the first 3 months depending on patient factors. Low-dose aspirin is given long-term.
What are Mechanical valves - target INR?
Mechanical valves - target INR:
aortic: 3.0
mitral: 3.5
NICE guidelines (2021) suggest which patients with AF should not have rate control as first-line?
1.A reversible cause for their AF
2.New onset atrial fibrillation (within the last 48 hours)
3.Heart failure caused by atrial fibrillation
4.Symptoms despite being effectively rate controlled
What are the two scenarios where cardioversion may be used in atrial fibrillation?
- electrical cardioversion as an emergency if the patient is haemodynamically unstable
- electrical or pharmacological cardioversion as an elective procedure where a rhythm control strategy is preferred.
What are the principles for AF management?
Rheumatic fever develops following infection with what?
Streptococcus pyogenes.
What is the diagnosis of rheumatic fever based on?
Diagnosis is based on evidence of recent streptococcal infection accompanied by:
2 major criteria
1 major with 2 minor criteria
What is the major and minor criteria of the diagnosis of rheumatic fever?
Major criteria
erythema marginatum
Sydenham’s chorea: this is often a late feature
polyarthritis
carditis and valvulitis (eg, pancarditis)
The latest iteration of the Jones criteria (published in 2015) state that rheumatic carditis cannot be based on pericarditis or myocarditis alone and that there must be evidence of endocarditis (the clinical correlate of which is valvulitis which manifests as a regurgitant murmur)
subcutaneous nodules
Minor criteria
raised ESR or CRP
pyrexia
arthralgia (not if arthritis a major criteria)
prolonged PR interval
What is the evidence of recent streptococcal infection
Evidence of recent streptococcal infection
raised or rising streptococci antibodies,
positive throat swab
positive rapid group A streptococcal antigen test
What is the management of rheumatic fever?
Management
Outline of management
antibiotics: oral penicillin V
anti-inflammatories: NSAIDs are first-line
treatment of any complications that develop e.g. heart failure
What is the management of SVTs?
Management of supraventricular tachycardia in patients without life-threatening features involves a stepwise approach, trying each step to see whether it works before moving on.
Step 1: Vagal manoeuvres
Step 2: Adenosine
Step 3: Verapamil or a beta blocker
Step 4: Synchronised DC cardioversion
Patients with life-threatening features, such as loss of consciousness (syncope), heart muscle ischaemia (e.g., chest pain), shock or severe heart failure, are treated with synchronised DC cardioversion under sedation or general anaesthesia. Intravenous amiodarone is added if initial DC shocks are unsuccessful.
Acute management
vagal manoeuvres:
Valsalva manoeuvre: e.g. trying to blow into an empty plastic syringe
carotid sinus massage
intravenous adenosine
rapid IV bolus of 6mg → if unsuccessful give 12 mg → if unsuccessful give further 18 mg
contraindicated in asthmatics - verapamil is a preferable option
electrical cardioversion
Prevention of episodes
beta-blockers
radio-frequency ablation
What is Wolff-Parkinson White (WPW) syndrome?
Wolff-Parkinson White (WPW) syndrome is caused by a congenital accessory conducting pathway between the atria and ventricles leading to atrioventricular re-entry tachycardia (AVRT). As the accessory pathway does not slow conduction AF can degenerate rapidly to VF.
What are the ECG features of WPW?
Possible ECG features include:
short PR interval
wide QRS complexes with a slurred upstroke - ‘delta wave’
left axis deviation if right-sided accessory pathway
in the majority of cases, or in a question without qualification, Wolff-Parkinson-White syndrome is associated with left axis deviation
right axis deviation if left-sided accessory pathway
Differentiating between type A and type B
type A (left-sided pathway): dominant R wave in V1
type B (right-sided pathway): no dominant R wave in V1
What are other conditons asscoiated with WPW?
Associations of WPW
HOCM
mitral valve prolapse
Ebstein’s anomaly
thyrotoxicosis
secundum ASD
What is the management of WPW?
Management
definitive treatment: radiofrequency ablation of the accessory pathway
medical therapy: sotalol***, amiodarone, flecainide
sotalol should be avoided if there is coexistent atrial fibrillation as prolonging the refractory period at the AV node may increase the rate of transmission through the accessory pathway, increasing the ventricular rate and potentially deteriorating into ventricular fibrillation
Patients with Wolff-Parkinson-White syndrome (pre-excitation syndrome) with possible atrial arrhythmias (e.g., atrial fibrillation or atrial flutter) should not have adenosine, verapamil or a beta blocker, as these block the atrioventricular node, promoting conduction of the atrial rhythm through the accessory pathway into the ventricles, causing potentially life-threatening ventricular rhythms. Sometimes it can be difficult to distinguish this from SVT, so the involvement of experienced seniors is essential. In this scenario, the usual management is procainamide (which does not block the AV node) or electrical cardioversion (if unstable).
What are the complications of MI?
DREAD
D – Death- cardiac arrest due to VF
R – Rupture of the heart septum or papillary muscles
E – “oEdema” (heart failure)
A – Arrhythmia and Aneurysm
D – Dressler’s Syndrome
Cardiogenic shock
If a large part of the ventricular myocardium is damaged in the infarction the ejection fraction of the heart may decrease to the point that the patient develops cardiogenic shock
Chronic heart failure
As described above, if the patient survives the acute phase their ventricular myocardium may be dysfunctional resulting in chronic heart failure. Loop diuretics such as furosemide will decrease fluid overload. Both ACE-inhibitors and beta-blockers have been shown to improve the long-term prognosis of patients with chronic heart failure.
Tachyarrhythmias
Ventricular fibrillation, as mentioned above, is the most common cause of death following a MI. Other common arrhythmias including ventricular tachycardia.
Bradyarrhythmias
Atrioventricular block is more common following inferior myocardial infarctions.
Pericarditis
Pericarditis in the first 48 hours following a transmural MI is common (c. 10% of patients). The pain is typical for pericarditis (worse on lying flat etc), a pericardial rub may be heard and a pericardial effusion may be demonstrated with an echocardiogram.
Dressler’s syndrome tends to occur around 2-6 weeks following a MI. The underlying pathophysiology is thought to be an autoimmune reaction against antigenic proteins formed as the myocardium recovers. It is characterised by a combination of fever, pleuritic pain, pericardial effusion and a raised ESR. It is treated with NSAIDs.
Left ventricular aneurysm
The ischaemic damage sustained may weaken the myocardium resulting in aneurysm formation. This is typically associated with persistent ST elevation and left ventricular failure. Thrombus may form within the aneurysm increasing the risk of stroke. Patients are therefore anticoagulated.
Left ventricular free wall rupture
This is seen in around 3% of MIs and occurs around 1-2 weeks afterwards. Patients present with acute heart failure secondary to cardiac tamponade (raised JVP, pulsus paradoxus, diminished heart sounds). Urgent pericardiocentesis and thoracotomy are required.
Ventricular septal defect
Rupture of the interventricular septum usually occurs in the first week and is seen in around 1-2% of patients. Features: acute heart failure associated with a pan-systolic murmur. An echocardiogram is diagnostic and will exclude acute mitral regurgitation which presents in a similar fashion. Urgent surgical correction is needed.
Acute mitral regurgitation
More common with infero-posterior infarction and may be due to ischaemia or rupture of the papillary muscle. Acute hypotension and pulmonary oedema may occur. An early-to-mid systolic murmur is typically heard. Patients are treated with vasodilator therapy but often require emergency surgical repair.
What is Dresslers syndrome?
Dressler’s syndrome is also called post-myocardial infarction syndrome. It usually occurs around 2 – 3 weeks after an acute myocardial infarction. It is caused by a localised immune response that results in inflammation of the pericardium, the membrane that surrounds the heart (pericarditis).
Presentation, Diagnosis, management of dresslers syndrome
It presents with pleuritic chest pain, low-grade fever and a pericardial rub on auscultation. A pericardial rub is a rubbing, scratching sound that occurs alongside the heart sounds. It can cause a pericardial effusion and rarely a pericardial tamponade (where the fluid constricts the heart and inhibits function).
A diagnosis can be made with an ECG (global ST elevation and T wave inversion), echocardiogram (pericardial effusion) and raised inflammatory markers (CRP and ESR).
Management is with NSAIDs (e.g., aspirin or ibuprofen) and, in more severe cases, steroids (e.g., prednisolone). Pericardiocentesis may be required to remove fluid from around the heart, if there is a significant pericardial effusion.
what is acute pericarditis?
Acute pericarditis is a condition referring to inflammation of the pericardial sac, lasting for less than 4-6 weeks.
What are the causes of pericarditis?
Idiopathic (no underlying cause)
Infection (e.g., tuberculosis, HIV, coxsackievirus, Epstein–Barr virus and other viruses)
Autoimmune and inflammatory conditions (e.g., systemic lupus erythematosus and rheumatoid arthritis)
Injury to the pericardium (e.g., after myocardial infarction, open heart surgery or trauma)
Uraemia (raised urea) secondary to renal impairment
Cancer (lung cancer, breast cancer)
Medications (e.g., methotrexate)
hypothyroidism
radiotherapy
Presentation of pericarditis
Two key presenting features should make you think of pericarditis:
Chest pain
Low-grade fever
The chest pain is:
Sharp
Central/anterior
Worse with inspiration (pleuritic)
Worse on lying down
Better on sitting forward
Pericardial friction rub on auscultation is a key examination finding. A pericardial rub is a rubbing, scratching sound that occurs alongside the heart sounds.
other symptoms include a non-productive cough, dyspnoea and flu-like symptoms
What are the investigations for pericarditis and ECG changes?
Investigations
Blood tests show raised inflammatory markers (white blood cells, CRP and ESR).
ECG changes include:
Saddle-shaped ST-elevation
PR depression
Echocardiogram can be used to diagnose a pericardial effusion.
all patients with suspected acute pericarditis should have transthoracic echocardiography
Management of pericarditis
Management
-Non-steroidal anti-inflammatory drugs (NSAIDs) are the mainstay of treatment (e.g., aspirin or ibuprofen)
-Colchicine (taken longer-term, e.g., 3 months, to reduce the risk of recurrence)
Steroids may be used second-line, in recurrent cases or associated with inflammatory conditions (e.g., rheumatoid arthritis)
Underlying causes, such as tuberculosis and renal failure, should be treated appropriately.
Pericardiocentesis may be required to remove fluid from around the heart if there is a significant pericardial effusion or tamponade.
the majority of patients can be managed as outpatients
patients who have high-risk features such as fever > 38°C or elevated troponin should be managed as an inpatient
treat any underlying cause
most patients however will have pericarditis secondary to viral infection, meaning no specific treatment is indicated
strenuous physical activity should be avoided until symptom resolution and normalisation of inflammatory markers
a combination of NSAIDs and colchicine is now generally used for first-line for patients with acute idiopathic or viral pericarditis
until symptom resolution and normalisation of inflammatory markers (usually 1-2 weeks) followed by tapering of dose recommended over
Principles of diagnosing PE
The NICE guidelines (2021) recommend for anticoagulation in AF
The NICE guidelines (2021) recommend for anticoagulation:
Direct-acting oral anticoagulants (DOACs) first-line
Warfarin second-line, if DOACs are contraindicated
CHA2DS2-VASc is a tool for assessing whether a patient with atrial fibrillation should start anticoagulation. It is a list of risk factors that increase the likelihood of a stroke. The higher the score, the higher the risk of developing a stroke or TIA.
CHA2DS2-VASc is a mnemonic for the factors that score a point:
C – Congestive heart failure
H – Hypertension
A2 – Age above 75 (scores 2)
D – Diabetes
S2 – Stroke or TIA previously (scores 2)
V – Vascular disease
A – Age 65 – 74
S – Sex (female)
NICE (2021) recommends, based on the CHA2DS2-VASc score:
0 – no anticoagulation
1 – consider anticoagulation in men (women automatically score 1)
2 or more – offer anticoagulation
Aspirin alone is not used for stroke prevention in atrial fibrillation
What is the first line treatment for VT?
IV amiodarone
what is the treatment for Polymorphic ventricular tachycardia, such as torsades de pointes?
IV magnesium
Ejection systolic murmur is classically seen in?
Aortic stenosis
Describe the murmur in aortic stenosis
Aortic stenosis causes an ejection-systolic, high-pitched murmur due to the high blood flow velocity through the aortic valve. This has a crescendo-decrescendo character due to the speed of blood flow across the value during the different periods of systole. Flow during systole is slowest at the start and end and fastest in the middle.
The murmur radiates to the carotids as the turbulence continues into the neck.
What are the clinical signs and features of aortic stenosis?
Clinical features of symptomatic disease
chest pain
dyspnoea
syncope / presyncope (e.g. exertional dizziness)
murmur
an ejection systolic murmur (ESM) is classically seen in aortic stenosis
classically radiates to the carotids
this is decreased following the Valsalva manoeuvre
Other signs of aortic stenosis:
Thrill in the aortic area on palpation
Slow rising pulse
Narrow pulse pressure (the difference between systolic and diastolic blood pressure)
Exertional syncope (lightheadedness and fainting when exercising) due to difficulty maintaining a good flow of blood to the brain
Features of severe aortic stenosis
narrow pulse pressure
slow rising pulse
delayed ESM
soft/absent S2
S4
thrill
duration of murmur
left ventricular hypertrophy or failure
Causes of aortic stenosis
Causes of aortic stenosis
degenerative calcification (most common cause in older patients > 65 years)
bicuspid aortic valve (most common cause in younger patients < 65 years)
William’s syndrome (supravalvular aortic stenosis)
post-rheumatic disease
subvalvular: HOCM
Management of aortic stenosis
Management
if asymptomatic then observe the patient is a general rule
if symptomatic then valve replacement
if asymptomatic but valvular gradient > 40 mmHg and with features such as left ventricular systolic dysfunction then consider surgery
options for aortic valve replacement (AVR) include:
surgical AVR is the treatment of choice for young, low/medium operative risk patients. Cardiovascular disease may coexist. For this reason, an angiogram is often done prior to surgery so that the procedures can be combined
transcatheter AVR (TAVR) is used for patients with a high operative risk
balloon valvuloplasty
may be used in children with no aortic valve calcification
in adults limited to patients with critical aortic stenosis who are not fit for valve replacement
What is acute coronary syndrome?
Acute coronary syndrome (ACS) is usually the result of a thrombus from an atherosclerotic plaque blocking a coronary artery. When a thrombus forms in a fast-flowing artery, it is formed mainly of platelets. This is why antiplatelet medications such as aspirin, clopidogrel and ticagrelor are the mainstay of treatment.
What is the classification/types of acute coronary syndrome
ST-elevation myocardial infarction (STEMI): ST-segment elevation + elevated biomarkers of myocardial damage
non ST-elevation myocardial infarction (NSTEMI): ECG changes but no ST-segment elevation + elevated biomarkers of myocardial damage
unstable angina
What is the presentation of ACS?
Acute coronary syndrome typically presents with central, constricting chest pain.
The chest pain is often associated with:
Pain radiating to the jaw or arms
Nausea and vomiting
Sweating and clamminess
A feeling of impending doom
Shortness of breath
Palpitations
Who is at risk of silent MI?
Diabetics
What is the initial management of ACS?
MONA
Morphine
Oxygen
Nitrates
Aspirn
Common management of all patients with ACS
Initial drug therapy
aspirin 300mg
oxygen should only be given if the patient has oxygen saturations < 94% in keeping with British Thoracic Society oxygen therapy guidelines
morphine should only be given for patients with severe pain
previously IV morphine was given routinely
evidence, however, suggests that this may be associated with adverse outcomes
nitrates
can be given either sublingually or intravenously
useful if the patient has ongoing chest pain or hypertension
should be used in caution if patient hypotensive
What is the management of STEMI?
what Further antiplatelet prior to PCI is given
this is termed ‘dual antiplatelet therapy’, i.e. aspirin + another drug
if the patient is not taking an oral anticoagulant: prasugrel
if taking an oral anticoagulant: clopidogrel
What is the drug therapy given during PCI?
Drug therapy during PCI
patients undergoing PCI with radial access:
unfractionated heparin with bailout glycoprotein IIb/IIIa inhibitor (GPI) - this is the action of using a GPI during the procedure when it was not intended from the outset, e.g. because of worsening or persistent thrombus
patients undergoing PCI with femoral access:
bivalirudin with bailout GPI
When should ECG be repeated after Fibrinolysis for STEMI
An ECG should be repeated after 60-90 minutes to see if the ECG changes have resolved. If patients have persistent myocardial ischaemia following fibrinolysis then PCI should be considered.
What is the management of NSTEMI
What are the medications for secondary prevention of MI?
Medication for secondary prevention can be remembered with the “6 A’s” mnemonic:
Aspirin 75mg once daily indefinitely
Another Antiplatelet (e.g., ticagrelor or clopidogrel) for 12 months
Atorvastatin 80mg once daily
ACE inhibitors (e.g. ramipril) titrated as high as tolerated
Atenolol (or another beta blocker – usually bisoprolol) titrated as high as tolerated
Aldosterone antagonist for those with clinical heart failure (i.e. eplerenone titrated to 50mg once daily)
How is blood pressure classified?
How is hypertension diagnosed?
what should be given to patients who are in VF/pulseless VT after 3 shocks have been administered?
amiodarone 300 mg should be given to patients who are in VF/pulseless VT after 3 shocks have been administered.
a further dose of amiodarone 150 mg should be given to patients who are in VF/pulseless VT after 5 shocks have been administered
lidocaine used as an alternative if amiodarone is not available or a local decision has been made to use lidocaine instead
Infective endocarditis in intravenous drug users most commonly affects which valve?
Tricuspid valve
What is the most commonly affected valve overall?
Mitral valve
Early diastolic murmur is classically seen in
Aortic regurgitation
What are the causes of aortic regurgitation
It can be caused either by disease of the aortic valve or by distortion or dilation of the aortic root and ascending aorta.