Vascular Medicine (week 7) Flashcards
What is the definition of atherosclerosis?
A disease of the arteries characterized by the deposition of fatty material on their inner walls.
Presentation of atherosclerosis depends largely on which arteries are affected. How will it manifest in the coronary arteries?
Angina
MI
Microvascular disease
Presentation of atherosclerosis depends largely on which arteries are affected. How will it manifest in the carotid arteries?
Stroke
TIA (via thrombus)
Presentation of atherosclerosis depends largely on which arteries are affected. How will it manifest in the peripheral arteries?
Exertional leg pain (claudication)
Critical limb ishaemia
Presentation of atherosclerosis depends largely on which arteries are affected. How will it manifest in the Renal arteries?
CKD
Reno-vascular HTN
Why does atherosclerosis increase risk of ACS, stroke and critical limb ischaemia?
Presence of endothelial dysfunction after established atherosclerosis; this leads to Vasoconstriction and decreased perfusion ischaemia but also an increased risk of plaques rupturing and forming a thrombus.
In combination these increase the risk of ACS, STROKE & CRITICAL LIMB ISCHAEMIA
What are the symptoms of peripheral arterial disease?
Most cases are asymptomatic.
In symptomatic patients:
- Most have atypical exertional leg pain.
- 10-30% present with classic intermittent claudication.
- Rest pain or ischaemic ulcers are signs of critical limb ishaemia.
What are the signs of peripheral arterial disease?
The 6 Ps
Pain, Pallor, Pulselessness, Poikilothermia (“coldness”), Paralysis, Paresthesia
How do we diagnose peripheral arterial disease? What are the parameters?
Ankle-brachial index (ABI).
ABI is the ratio of ankle SBP to brachial SBP
(measured at the ankle by Doppler USS)
- Ankle-Brachial Index Severity
- > 1.30 Noncompressible
- 0.91-1.30 Normal
- 0.71-0.90 Mild
- 0.41-0.70 Moderate
- 0-0.40 Severe
When do you usually get symptoms of atherosclerosis in coronary artery disease?
Atherosclerosis is usually asymptomatic until vessels narrow severely or are totally blocked.
This is usually down to an ACUTE event - like a THROMBUS (ruptured plaque)
What is the most common precipitating event to cause symptoms in patients with coronary artery disease?
ACUTE event - like a THROMBUS (ruptured plaque)
What are the most common symptoms of coronary artery disease?
- Chest pain
- Dyspnoea
- Palpitations
- Syncope
- Fatigue
- Peripheral oedema – this will happen if there is left ventricular damage due to MI and then develop heart failure.
How do we categorise CV risk factors (give 3 examples or each)?
Modifiable
• Smoking
• Hyperlipidemia – higher LDLs = higher risk.
• Hypertension – single biggest risk factor for having a recurrent stroke having had a single TIA.
• Diabetes Mellitus
Fixed
• Older age
• Male Sex
• FHx – especially stuff like familial hypercholesterolaemia – 50% chance if FHx positive.
• 1st degree relative who develops CVD at an early age (male below 55yrs, women below 65yrs)
• Ethnicity – Indian subcontinent at higher risk.
• Previous CVD
What is the single biggest risk factor for having a recurrent stroke having had a single TIA?
Hypertension
What is the metabolic syndrome?
Insulin resistance, associated with a cluster of risk factors
o Insulin resistance and hyper-insulinaemia
o Central obesity
o Hypertension
o Dyslipidaemia (Increased Triglycerides, decreased HDL-Cholesterol)
o Impaired glucose tolerance
What is angina?
A pain or discomfort in the chest or adjacent areas (caused by insufficient blood flow to the heart muscle)
What is the typical type of pain associated with angina?
Angina pains are typically central crushing chest pains and patients can describe it as having a heavy weight in the middle of your chest.
What is the typical location of pain associated with angina?
- Usually retrosternal, but radiation to the neck, jaw, epigastrium, or arms is not uncommon
- Pain above the mandible, below the epigastrium, or localized to a small area over the left lateral chest wall is rarely angina
What is the typical duration of pain associated with angina?
- Typically minutes in duration
- Fleeting discomfort or a dull ache lasting for hours is rarely angina
What are the common precipitating factors of angina?
Exertion – most important factor to consider.
Others = Emotion, Eating, Extreme weather
What is the difference between stable and unstable angina?
Unstable Angina = Angina pains which are rapidly worsening (on minimal/no exertion), or not relieved by rest.
Stable is relieved by rest
What are the non-organic differentials of chest pain?
Anxiety (very big one, especially if you start to hyperventilate) If they haven’t got angina this is one of your next big differentials.
What are the pulmonary differentials of chest pain? How do you differentiate?
- PE – sudden, sharp and severe
- Pleurisy – Inflammation of pleura, varies with respiration.
- Pneumothorax
What are the MSK differentials of chest pain? How do you differentiate?
Chostochondritis (sternal pain) or trauma
What are the GI differentials of chest pain? How do you differentiate?
Ulcer/reflux (worse after eating),
Gallstones,
Pancreatitis - back pain
What are the cardiac differentials of chest pain? How do you differentiate?
- Angina – shorter duration
- MI – Symptoms that are lasting longer than 15 mins, nausea, pale, etc.
- Pericarditis – Pain that varies with respiration and position (worse if you sit up)
- Aortic Dissection – tearing feeling, radiates to back.
What are the 2 categories that ACS is split into (from ECG)?
Give examples of each
No ST Elevation
a. NSTEMI
b. Unstable Angina – troponin is not elevated (this means no myocardial damage has been done)
ST Elevation
a. NQMI (non- Q wave MI) likely to have T wave changes
b. QwMI (Q wave MI) this implies the whole thickness of the myocardium had been infarcted to cause the Q-wave
Why do we split ACS into STEMI and NSTEMI?
We split NSTEMI and STEMI because treatment is so different.
o STEMI – straight to cath lab and get coronary arteries opened up
o NSTEMI – there is no evidence that acute management will make a significant difference to the long-term prognosis.
How does thrombus characteristics effect the presentation of an ACS?
o If the artery occludes completely, will lead to an MI (likely STEMI).
o If artery is sub-occlusive or occludes and then reopens, you will get unstable angina/NSTEMI
What is the ECG change that caries the highest 6 month mortality?
o T-wave inversion
o ST elevation
o ST depression
ACS mortality at 6 months (%)
o T-wave inversion – 3.4%
o ST elevation – 6.8%
o ST depression – 8.9%
What are the 3 factors that contribute to the diagnosis of ACS? (need 2 to diagnose ACS)
Chest Pain (clinical manifestation) o ECG changes consistent with ischaemia or necrosis. (perform immediately) o Elevation of cardiac markers
What is the classical clinical presentation of ACS?
- Chest pain associated with MI lasting longer than 20 minutes and not relieved by rest or nitroglycerin (GTN).
- May be accompanied by dyspnoea, nausea, vomiting, fatigue, diaphoresis, and palpitations
Atypical presentations (more common in diabetics/elderly) • Breathlessness, tachycardia, N&V, sweating and clamminess
When should you take the ECG of a patient with suspected ACS?
- Perform immediately
- If ECG is normal or non diagnostic in a patient with continuing symptoms repeat after 30mins
- If symptoms resolve repeat ECG after 2 hours – changes can occur late
- Repeat ECG if pain persists
Which factors of the ECG at the time of chest pain dictate risk of death or MI at 30 days?
• ST depression 10%
• T-wave inversion 5%
• No ECG changes 1-2%
The risk of death or MI at 30 days is strongly related to the ECG at the time of chest pain
• ST depression 10%
• T-wave inversion 5%
• No ECG changes 1-2%
Name 3 cardiac markers…
cardiac-specific troponins
creatine kinase (serum CK and CK-MB)
myoglobin
Which leads correlate to the Anterior/Septal region of the heart? Which artery is likely to be occluded?
V1, V2, V3 & V4
LAD
Which leads correlate to the Inferior region of the heart? Which artery is likely to be occluded?
II, III, aVF
RCA (&/or LCx)
Which leads correlate to the Lateral region of the heart? Which artery is likely to be occluded?
I, aVL, V5, V6
LCx or Diagonal of LAD
What does ST depression on an ECG suggest?
Ischaemia
What does T wave inversion on an ECG suggest?
Past MI/Ischaemic event
When is Troponin detectable, when do you measure it? When does it peak?
Detectable very early, within 3 hours.
Current ESC recommendations are to measure troponin on admission and 6-9 hours later,
Peaks at about 18 hours.
Apart from MI, when else can troponin be elevated?
PE, sepsis, AF, LVF and post-op
What Troponin measurements are required for a diagnosis of acute MI?
Current ESC recommendations are to measure troponin on admission and 6-9 hours later, a troponin result >99th centile (TnT > 14) and a rise or fall of >20% on the second sample required for diagnosis of AMI.
What score is used to stratify risk of ACS?
GRACE score
What does the GRACE score measure?
Gives you risk of death and death + MI, in hospital and after 6 months
What are the therapeutic goals of ACS treatments?
Reduce myocardial ischaemia
Control of symptoms
Prevention of MI and death
What categories of medications are used in the treatment of ACS?
o Anti-ischaemic agents
o Anti-platelet agents
o Anti-thrombin agents (Fibrinolytics)
o Coronary revascularisation
What are the drug therapies in NSTE-ACS?
o Aspirin o Clopidogrel / Ticagrelor o Fondaparinux o GPIIb/IIIa receptor antagonists (high risk pts only) o Beta blockers o Nitrates (if ongoing pain/LVD) o Statins (very good acutely and long term.) o ACE inhibitors
What is a common side effect of ACEi?
Dry cough
What is the post hospital discharge care in ACS?
o A Antiplatelets and ACE-I o B Beta blockers and Blood Pressure o C Cholesterol and Cigarettes o D Diet and Diabetes o E Education and Exercise
What is the most significant modifiable risk factor in CV and renal disease?
HTN
Risk of cardiovascular disease doubles for every 20/10 mmHg increase in BP
What is the most common cause of HTN?
Essential HTN (80% of cases)
What is the single highest stroke risk factor after a single TIA?
HTN
What are the renal causes of HTN?
- Glomerulonephritis
- Polycystic kidneys (autosomal dominant inheritance)
- Diabetes
- Reno vascular disease
What are the endocrine causes of HTN?
Steroid excess
hyperaldosteronism (Conn’s)
Which drugs can commonly cause HTN?
- Sympathomimetic amines (cold and flu remedies)
- Amphetamines - increase HR and BP
- Cocaine
- Oestrogens (e.g. OCP)
- Cyclosporin
- Erythropoetin
What vascular disease’s commonly cause HTN?
- Renal artery stenosis
- Fibromuscular disease in younger women – stent will cure
- Atheroma in middle age older smokers
- Coarctation