1 - ACS and Hypertension Flashcards
/What is ACS and what is the aetiology of this?
STEMI/NSTEMI/Unstable Angina
Due to either plaque rupture, thrombosis or inflammation
What are the signs and symptoms of ACS?
Signs: distress, anxiety, pallor, sweatiness, low grade fever, signs of heart failure (raised JVP, basal crepitations, 3rd heart sound)
Symptoms: acute central crushing chest pain lasting >20 minutes, nausea, sweating, dyspnoea, palpitations
What is a silent ACS and what patients does this occur in?
ACS without the chest pain. May have syncope, pulmonary oedema, epigastric pain, bomiting, post op hypotension, oliguria, diabetic hyperglycaemia
Seen in the elderly and diabetics often
What are some risk factors for ACS?
Non-Modifiable
- Age
- Male
- FHx
Modifiable
- Smoking
- Hypertension
- DM
- Hyperlipidaemia
- Obesity
- Cocaine use
How are each of the three acute coronary syndromes diagnosed based on their investigation findings?
Triad of symptoms, ECG changes and hs-TnI levels
All will have cardiac sounding chest pain
STEMI:
- ST elevation (>1mm in limb leads and 2mm in chest leads) or new LBBB
- hs-TNI >100ng/L
- CK often raised over 400
NSTEMI
- ST depression, T-wave inversion or normal
- hs-TnI>100ng/L
Unstable Angina
- ST depression, T wave inversion or normal
- hs-TnI is normal
What are the cardiac biomarkers used for a suspected MI and why?
- Trop I as high sensitivity as released from cardiomyocytes on necrosis.
- Begins to rise 3-4 hours after myocardial damage and remains high for 2 weeks
- Also check CK levels
- Need to see if falling, static or rising so take Trop I on admission then again in 3 hours to assess trend. Only need one result if onset of symptoms >3hours before presentation
What can cause false positive elevation of hs-TnI, meaning the patient is not having an MI?
Common: advanced renal failure, PE, CPR, ablation therapy
Less common: severe congestive heart failure, myocarditis, prolonged tachyarrhythmia
Rare: aortic dissection, aortic stenosis, hypertrophic cardiomyopathy, malignancy, stroke, severe sepsis
ALWAYS TAKE SERIAL MEASUREMENTS AND LOOK AT THE TREND NOT THE VALUE OF TEST
What ECG leads correspond to each area of the heart e.g anterior, septal etc?
VERY IMPORTANT
- Lateral: circumflex artery
- Septal: LAD
- Inferior: right coronary artery
- Posterior (V7-V9): circumflex artery
What are the immediate ECG changes in a STEMI? (excluding a posterior STEMI)
- ST elevation in 2 or more leads from the same zone e.g II, III, aVF.
- ST elevation >1mm in limb leads, >2mm in chest leads
- Presence of LBBB
- May have hyperacute tall T waves
What are the sequential ECG changes following an MI?
Within hours: ST elevation and hyperacute T waves or LBBB
24 hrs: T wave inversion, ST normal
Few days: pathological Q waves that persist
How does a posterior MI present on a 12 lead ECG, why is this and what should you do next?
IMPORTANT
- ST depression in leads V1-V4
- Reciprocal changes (upside down) due to looking at ischaemic myocardium from the other side
- Need to do 15 lead ECG (V7-V9 and RV4) in all STEMI patients, especially those with inferior STEMI or ST depression in V1-V4
What are the ECG changes in an NSTEMI or unstable angina?
- ST depression or elevation
- T wave inversion (reperfusion waves) or flattening
- T wave pseudonormalisation
- Previously established ECG changes e.g old MI, LV hypertrophy
- Normal ECG
What is T wave pseudonormalisation?
NSTEMIs often have T wave inversion that represents reperfusion of the area
On repeat ECG T waves may appear back to normal after firstly being inverted but this just means the artery is reoccluded
Apart from an ECG and cardiac enzymes, what other investigations should you carry out for a patient who presents with cardiac chest pain ?MI?
CXR: look for cardiomegaly, pleural effusion, widened mediastinum
Bloods: FBC, U+Es, random glucose, lipid profile, HbA1c, cardiac enzymes (2 tests 3 hours apart)
ECHO: regional wall abnormalities
What are some conditions that can mimic a STEMI on ECG?
- Early repolarisaition: usually leads V1 or V2, often in younger athletic patients and sometimes Afro-Caribbeans
- Pericarditis: widespread ST elevation
- Brugada Syndrome (sudden death): looks like anterior STEMI
- Takotsubo Cardiomyopathy: emotionial stress reaction in middle aged females that is temporary
What are some differential diagnoses for ACS?
- Stable angina
- Pericarditis
- Myocarditis
- Takotsubo cardiomyopathy
- Pneumothorax
- PE
- Oesophageal spasm/reflux
- MSK pain
What is the immediate management of an acute STEMI when a patient arrives at A+E?
- Brief history and exam with ECG (take bloods and CXR)
- Gain IV access
- Morphine with antiemetic e.g metoclopramide or cyclizine
- Aspirin 300mg if not already given
- Oxygen if hypoxic, keep >94%
- Anticoagulate (see next flashcard)
- Restore coronary perfusion if <12h since onset
Patients are given a loading dose of aspirin when they are having a STEMI. They also need to be further anticoagulated before reperfusion therapy, which drugs are used for this?
Prasugrel 60mg (inhibits ADP receptors)
If undergoing PPCI and are under 75 and weight more than 60kg and have not had prior TIA or stroke
Clopidogrel 600mg (inhibits ADP receptors)
If do not fufill criteria for prasugrel
Ticagrelor 180mg
If cannot have prasugrel or first line NSTEMI. Do not use if high bleeding risk
How do doctors choose which reperfusion therapy to offer to a patient with an acute STEMI?
PPCI
- Used if <12h since onset and can be given PPCI within 120 minutes of first medical contact
Thrombolysis
- Used if <12h since onset but cannot get PPCI within 120 minutes. Given infusion (e.g alteplase TPA) then transferred to PCI centre
No reperfusion
- If presenting >12h, just given fondaparinux or enoxaparin
What are some contraindications for treating a STEMI with thrombolysis?
- Previous intracranial haemorraghe
- Ischaemic stroke <6months ago
- Recent major head trauma/surgery
- Known bleeding disorders
- Liver biopsy or LP in past 24 hours
- Pregnancy
- GI bleeding
- Cerebral malignancy
What blood tests are essential for a patient with a STEMI?
- Cardiac enzymes (TropI)
- FBC
- Lipid profile
- Random blood glucose
- HbA1c
What medications are patients started on after an MI and for how long?
- Aspirin 75mg for life
- Ticagrelor (or another antiplatelet e.g Clopidogrel/Prasugrel) for 12 months
- ACEi or ARB for hypertension (checking renal function)
- Beta-blocker to lower heart rate (e.g Bisoprolol)
- Statin (e.g atorvastatin 80mg or rosuvastatin 5mg). Use ezetimibe if all statins have side effects
ATABS (also consider PPI for gastric protection with antiplatlets)
How much do you want LDL cholesterol to be lowered by with a statin?
40% reduction in non-HDL cholesterol. Total cholesterol should be below 4
After initial management of a STEMI and starting them on some cardioprotective medications, what are some other management principles you need to do for the patient?
CONTROL RISK FACTORS AND MANAGE ANY COMPLICATIONS
- Smoking cessation
- Control diabetes <7.5% Type 2 and <7% Type 1
- Control hyoertension
- Encourage daily exercise with cardiac rehabilitation programme
- Advise diet low in saturated fats
If a patient is being anticoagulated for AF then has a STEMI and needs two more anticoagulants, what should you consider giving them?
Limit time on the drugs and give them a PPI
What are some complications of a STEMI and how are they managed?
- Heart failure: diuretics e.g Epleronone
- Cardiogenic shock: need inotropes and balloon pumps]
- Valve damage e.g Mitral Regurg: may present with pulmonary oedema, needs valve replacement
- Ventricular Septal Defect: pansystolic murmur that is diagnosed on ECHO and needs surgery
- Pericarditis: give NSAIDs
How long after an MI can a patient return to work and driving?
Driving: 1 week after successful angioplasty or 4 weeks after unsuccessfil angioplasty
Work: depends on clinical progress and nature of work. Should be encourage to modify work activities
How is an NSTEMI/Unstable angina managed immediately?
- Pain relief with morphine
- Aspirin 300mg
- Start LMWH (Enoxaparin for 48h based on weight and creatinine)
- Repeat ECG
- Calculate if low or high risk with GRACE score
- If high risk >3% give Ticagrelor and offer angiography
- Consider antianginals whilst waiting for angiography e.g nitrates, ranolazine, CCBs
What is the GRACE score?
Score that risk stratifies a patients 6 month mortality with ACS. If >3% then high risk
Looks at age, heart rate, systolic BP, creatinine, abnormal cardiac enzymes, ST segment abnormalities
What medications should patients be placed on after an NSTEMI?
Same as with a STEMI, ATABS!!!!!
- Dual antiplatelet
- ACEi
- Beta blocker
- Statin
Make sure you address modifiable risk factors e.g hyperlipidaemia, diabetes, ACEi, statin
What is angina and how does it present?
Symptomatic reversible myocardial ischaemia causing chest discomfort
- Constricting/heavy discomfort to chest, jaw, shoulders or arms
- Symptoms brought on by exertion
- Symptoms relieved within 5 mins of rest or with GTN
What are some associated symptoms with angina if it is severe, and what symptoms make the diagnosis of angina less likely?
Associated symptoms: fear, sweating, nausea, dyspnea
Less likely to be angina: pain that is continuous, pleuritic or worse with swallowing, palpitations, dizziness, tingling
Angina can be difficult to distinguish from other differentials e.g GORD, MSK pain, pulmonary disease. What makes a diagnosis of angina more likely?
Two or more risk factors for coronary artery disease means the chest pain is more likely to be due to angina:
- Smoking
- Hypertension
- Valvular heart disease
Apart from exercise, what are some other things that can precipitate angina?
- Emotion
- Cold weather
- Heavy meals
Angina is usually due to atheromas in the coronary arteries (coronary artery disease). What are some other conditions that can cause symptoms of angina in the absence of coronary artery disease?
- Aortic syenois
- Hypertensive heart disease
- Hypertrophic cardiomyopathy
What is decubitus angina and variant (Prinzmetal) angina?
Decubitus: precipitated by laying flat
Variant: caused by coronary artery spasm, occurs at rest
What questions are important to answer in the history of a patient with suspected stable angina?
What are some things you should look at on examination of a patient with suspected angina?
- Height and weight for BMI
- Blood pressure
- Presences of murmurs (particularly aortic stenosis)
- Evidence of hyperlipidaemia
- Evidence of peripheral vascular diease or carotid bruits
What are some tests you should do as standard for all patients with suspected angina
- FBC, U+Es, TFTs HbA1c, Gluocose
- Full lipid profile
- Resting 12 lead ECG
- Consider ECHO and CXR
Patients who have angina like pain are scored based on their estimated likelihood of CAD. What investigations should you offer for different likelihood scores?
- 61-90%: Invasive coronary angiography
- 30-60%: Functional imaging e.g stress MRI, echo or myoview
- 10-29%: CT calcium scoring. If zero likelihood is minimal. If 1-400 consider CTCA or stress perfusion imaging. If >400 CTCA