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  • Prolonged neurological sequelae after syncope: points to neurological cause
    • Elderly - significant small vessel disease (vascular dementia) --> hypotension due to primary cardiac cause results in slow neurological recovery (so the neurological sequelae may occur even without a neurological cause). Vasodilator medications can also make recovery more slow
  • Very important - get witness' recount of events: may use specific questions to get information on the event: but memory is a faulty tool
    • History may not be absolutely what happened
  • This history is very superficial - e.g. look for cardiac features when talking about chest tightness. E.g. SOCRATES
  • Hemodynamic stability
    • Need to know their baseline, need recent change. Need time to watch them
  • Need to take postural blood pressure (postural hypotension is very common in the elderly)
    • What is a significant change in BP: 20mmHg drop in systolic between lying down (after time to lie around) and then standing up (after 30 seconds) - there will be compensatory tachycardia that should stop the BP falling too far (baroreceptor reflex)
  • Aortic stenosis: very common in the elderly (calcific degeneration, goes with atherosclerosis (same process that causes atherosclerosis))
    • Look for narrow pulse pressure (NB: elderly often have a very wide pulse pressure)
      • Narrow pulse pressure is sensitive (not specific - all sorts of things might be responsible for a narrow pulse pressure). Slow rising. Feel it at the carotid. Very slow and irregularly rising, doesn't rise very high (anacrotic)
        • NB: collapsing pulse would be best felt at the radial artery with the arm raised
      • Aortic stenosis normally has crescendo-decrescendo (doesn't indicate severity)
      • A2 will be delayed in severe aortic stenosis (very hard to hear; even cardiologists)
      • Most reliable sound - very late peak in the crescendo-decrescendo murmur = very severe aortic stenosis (highly dependent on heart rate)
  • Want to take a history that becomes more and more focussed through questioning (refine differential diagnosis as you go)
  • Severe aortic stenosis can result in significant fall in CO --> syncope; due to increased demand (e.g. vasodilation/exertion)
    • This is a marker of critical aortic stenosis

ECG

  • Palpitations
  • Think about medications as a cause for ANY elderly presentation
  • Left axis deviation: positive lead 1, negative in lead 2 and aVF
  • Wide QRS = some ventricular block (>3 large squares)
  • Left anterior hemiblock = left axis deviation + Initial R wave in 2, 3, aVF (the inferior leads)
  • First degree heart block: PR >0.2 = 1 big square. Poor conduction between the AV node. Not significant in everyone
  • V1 RSR' + wide QRS = right bundle branch block
  • So in this patient, there is only communication from A to V through left posterior fascicle
  • He has trifascicular block at rest
    • Loses one more fascicle = complete heart block = Ventricular rate is much lower than sinus rhythm
  • Transient complete heart block - ischaemia (i.e. intermittent chest tightness). Transient ischaemia of the last bundle = complete heart block
    • Causes: stenosis, embolic, thrombotic
  • DDx: aortic stenosis, complete heart block, ischaemic heart disease, medications

Blood test results

  • Troponin did not rise
  • Electrolytes, urea and creatinine normal
  • Elevated cholesterol
  • Normal range: +/- 2SD = 95% of population
    • Each laboratory has to generate their own normal range (from a healthy sample population) - the healthy population will have a normal distribution
  • Pre-test probability: if someone from the healthy population (no risk factors etc) has a test, they'll have a low pretest probability, so that if they test positive, it could just be that they're in the 1/20 outside the range 5-95%.
    • Can have have healthy normals: 2.5% are above normal range, 2.5% are below
    • Normal healthy person will have 1 in 20 tests outside the normal range
  • Pre-test probability high and then a positive test = much more significant than positive test in someone with no other risk factors
  • LVH: past hypertension; aortic stenosis (high afterload)
  • Aortic valve: calcified and thickened
  • Gradient across valve should be 0; his is 60 (e.g. 180mmHg inside ventricle, 120 outside ventricle)
    • Cardiac catheter is better than Echo in determining gradient across valve (has transducer in there)
  • Echo calculates it with valve area and velocity of flow across the valve
    • Estimates it based on the valve being round (but it's actually irregular)
  • Echo and cardiac catheter lab let you know the severity of the AS: see here - http://www.uptodate.com/contents/aortic-valve-area-in-aortic-stenosis

ECG 2

  • Normal PR interval (has lost RSR' what). First degree heart block can come and go, not RBBB
  • Ventricular ectopics = abnormal site of conduction in the ventricle; normally occur not in runs, and come from all different places in the ventricle
  • Rate is 150+ beats/min in the ventricular ectopic
  • This is ventricular tachycardia (broad QRS, rapid rate, in a run)
  • Can degenerate into ventricular fibrillation - with no diastolic filling time
  • SVT would have had a normal QRS - so this isn't SVT (abnormal depolarisation of the ventricles)
    • Atrial flutter/atrial fibrillation can cause this
  • An SVT that looks like VT will have a weird conduction pathway (could be an atrial tachycardia with an abnormal conduction pathway) - really rapid SVT can preferentially use an aberrant pathway
    • It's important
    • To differentiate between the two: look at the rhythm (AF = irregularly irregular) - line up the QRSs and mark them on a piece of paper, and move them somewhere else to see whether it's regular or not
    • VT is typically absolutely regular
  • This case might actually be atrial fibrillation which is always irregular

Management

  • Should we
    • put in an implantable defibrillator (it can have huge psychological distress - people know they'd die without it when it went off)
    • replace aortic valve
    • treat heart block
    • pacemaker (for complete heart block)
    • electrophysiological studies (identify abnormal pathway and ablate it with laser/heat)
  • Severe AS has a predictable prognostic pathway --> follow them with echocardiography and symptoms
  • Holter monitor for a 24 hour ECG monitor. Patient can indicate if they have symptoms with the ECG; or implantable monitors
  • Government subsidy = 1/3 of private health insurance (public money goes into it), also Medicare copayments
    • So the public pays ~50% of private costs
      • So private health insurance is not an excuse to management: it really shouldn't make any difference to management
  • Anti-arrhythmic agents: they're actually pro-arrhythmic: so it's a sadface, don't give these (induces arrhythmias in unstable myocardium)