Cardiovascular Flashcards
What are the reversible causes of cardiac arrest?
4 Hs: Hypovolaemia, hypoxia, hypothermia, hypo/hyperkalaemia (and other metabolic disturbances)
4 Ts: Thrombosis (coronary or pulmonary), Tension pneumothorax, Tamponade - cardiac, toxins
What are the ‘shockable rhythms’ in cardiac arrest for which a defibrillator can be used?
Ventricular fibrillation
Pulseless ventricular tachycardia
In the shockable rhythms, when should shocks be administered via the defibrillator?
As soon as it’s recognised that the rhythm is shockable and then every after every 2-minute cycle of CPR (as long as the rhythm remains to be VF/pulseless VT
How often should adrenaline be administered in cardiac arrest with shockable rhythms?
After the 3rd shock then after every alternate cycle (i.e. every 3-5 mins thereafter)
How often should adrenaline be administered in cardiac arrest with non-shockable rhythms?
Adrenaline 1mg 1:10000 should be given as soon as possible. Should be treated with 2 minutes of CPR prior to reassessment of the rhythm
What additional drug can be given in shockable rhythm cardiac arrest?
Amiodarone 300mg iv after the 3rd shock
STEMI is diagnosable based on ECG changes (and confirmed with troponin results), what ECG changes are diagnostic of STEMI?
ST elevation in at least 2 anatomically contiguous leads or new Left bundle branch block
Regarding coronary artery occlusion, how does STEMI differ from NSTEMI or unstable angina?
STEMI - indicates complete occlusion of an artery
NSTEMI/unstable angina - indicates partial occlusion
Which 3 patient groups are most likely to have a ‘silent MI’ - MI without chest pain?
The elderly
Women
Diabetics
What will an ECG show in NSTEMI?
Non-specific changes T-wave inversion Hyper-acute T waves ST depression (these changes can also be seen in unstable angina but more likely that the ECG will be normal)
How is unstable angina distinguishable from NSTEMI?
Only through troponin results which will be negative in unstable angina but raised in NSTEMI
Changes in which ECG leads indicate a blockage in the right coronary artery supplying the inferior part of the heart?
Leads II, III, aVF
Changes in which ECG leads indicate a blockage in the left anterior descending artery supplying the anterior part of the heart?
Leads V1-V4
Changes in which ECG leads indicate a blockage in the left circumflex artery supplying the lateral part of the heart?
Leads I, aVL, V5, V6
What is the acute management of ACS?
M - morphine 5-10mg iv and metaclopramide 10mg iv
O - oxygen (if sats <94%)
N - Nitrates (GTN spray sublingually)
A - Aspirin 300mg po
T - Ticagrelor 180mg stat dose (clopidogrel 300mg is an alternative)
A LMWH may also be given, particularly in NSTEMI
What are the definitive management options for STEMI?
Contact local coronary care unit for:
Percutaneous coronary intervention (PCI) - if available within 2 hours
Thrombolysis - with e.g. tenecteplase if PCI not available within 2 hours
What scoring system can be used to calculate whether a patient with NSTEMI should receive PCI?
Grace score.
If > 5%, PCI advised
What 5 drugs form the secondary prevenatative pharmacological measures in ACS?
B - Beta-blocker e.g. bisoprolol 10mg A - Aspirin 75mg S - Statin e.g. atorvastatin 80mg I - Inhibitor of ACE e.g. ramipril 10mg C - Clopidogrel 75mg or ticagrelor 60mg bd
What are the complications of MI?
D – Death/cardiac arrest R – Rupture of the heart septum or papillary muscles E – “Edema” (Heart Failure) A – Arrhythmia and Aneurysm D – Dressler’s Syndrome
What is Dressler’s syndrome?
An autoimmune reaction against antigenic proteins formed as the myocardium recovers after MI, causing pericarditis that typically occurs around 2-6 weeks after an MI. It is characterised by a combination of fever, pleuritic pain, pericardial effusion and a raised ESR. It is treated with NSAIDs.
How does stable angina (aka angina pectoris) differ from ACS?
Stable angina is usually brought on by exertion as opposed to coming on at rest in ACS, and in stable angina, symptoms are usually relieved after resting for up to 5 mins or with GTN spray - this is not the case in ACS.
What is the Gold Standard diagnostic investigation for angina pectoris?
CT coronary angiogram - highlights any stenosis of the coronary arteries
What percentage narrowing of a coronary artery diameter is considered significant?
> 70%
How is stable angina managed?
GTN spray to be used PRN when chest pain comes on.
Aspirin and atorvastatin.
Beta-blocker or rate-limiting calcium channel blocker if B-blocker not tolerated/contraindicated. If Sx not controlled with monotherapy and intolerant of other drug, consider adding a long acting nitrates (e.g. isosorbide mononitrate)/Ivabradine/Nicorandil/Ranolazine
If necessary, consider procedural/surgical intervention with PCI or CABG.
What is the classical appearance on ECG of atrial flutter?
‘Sawtooth’ appearance
How is atrial flutter managed?
Rate/rhythm control with beta blockers or cardioversion.
Treat the reversible underlying condition (e.g. hypertension or thyrotoxicosis).
Radiofrequency ablation of the re-entrant rhythm - curative for most patients.
Anticoagulation based on CHA2DS2VASc score.
What may be seen on an X-ray of someone with pulmonary oedema (as a result of heart failure)?
A - alveolar oedema (bat wing opacities) B - Kerley B lines C - cardiomegaly D - dilated upper lobe vessels E - pleural effusion
Heart failure is the end-stage of nearly all cardiovascular diseases, therefore identifying its cause and slowing the progression of the disease process is important. What are some causes of heart failure?
IHD and HTN (most common causes).
Valvular diseaes (e.g. mitral regurg, aortic stenosis, tricuspid regurg, ASD/VSD).
Arrhythmias.
Others: Pericardial effusion/pericarditis. Drugs (B-blockers/CCBs/alcohol/cocaine) Cardiomyopathies. Severe anaemia. Pulmonary hypertenison.
What additional heart sound may be heard in someone with heart failure?
‘Gallop’ S3
What are the cut offs for NT-proBNP for referring someone with suspected heart failure for echocardiogram, which will confirm the diagnosis?
> 2,000 – require urgent referral to cardiology for an echocardiogram (<2 weeks)
400 – 2,000 – require referral to cardiology for an echocardiogram (<6 weeks)
<400 – heart failure is unlikely and consider an alternative diagnosis
What classification system is commonly used to categorise severity of heart failure?
New York Heart Association [NYHA] Classification of Heart Failure. Class I (no limitation of function) to class IV (severe limitation, Sx may be present at rest)
What is the cut off for left ventricular ejection fraction (LVEF) for having heart failure with reduced ejection fraction (HFrEF)?
LVEF less than 40%.
LVEF is at least 40% in heart failure with preserved ejection fraction (HFpEF).
40-49% is classed as heart failure with mid-range ejection fraction (HFmrEF). 50+% is considered normal.
What is the management of heart failure?
Lifestyle measures: smoking cessation, lose weight if overweight, meditteranean diet, salt restriction, restricted fluid intake, reduce alcohol, cardiac rehab exercise.
Pharmacological: ACE-i and beta-blocker. Diuretic (furosemide commonly used). Consider adding Spironolactone if ACE-i and beta-blocker ineffective at controlling Sx.
Other: annual flu and pneumococcal vaccine, depression screen, treat other co-morbidities.
Surgery: may be required in cases of severe aortic stenosis or mitral regurgitation.
What is classed as stage 1 HTN?
BP in surgery/clinic is ≥140/90 mm Hg and ambulatory blood pressure monitoring (ABPM) or home blood pressure monitoring (HBPM) ranges from 135/85 mm Hg to 149/94 mm Hg.