cv middle tier Flashcards
bradycardia
- put a speed on it
- symptoms
- who is it normal for
- Less than 60bpm daytime and 50bpm night
- Usually asymptomatic
- Normal in athletes due to increased vagal tone and so increased parasympathetic activity
tachycardia
- put a speed on it
- two types
- More than 100bpm
- Supraventricular tachycardias - arise from atrium / AV junction — Atrial fibrillation/ atrial flutter
- Ventricular tachycardias - arise from ventricles
atrial fibrilation
- irregular?
- put a speed on it
- what is happening
- irregularly irregular - chaotic, atrial spasm
- 300-600bpm
- rapid activation of atria by multiple meandering re-entry wavelets. AV node responds intermittently , only a portion of impulses conducted on→ irregular ventricular rate
atrial fibrillation
- persistent
- permanent
- paroxysmal
- recurrent
- acute
- Persistent = continuous for 7days+, not self terminating
- Permanent = long term
- paroxysmal = self-terminating within 7 days
- Recurrent: two + episodes
- Acute = onset on last 48h
atrial fibrillation
- gender
- commonness
- age
- m>f
- most common arrythmia
- old
atrial fibrillation risk factors
- 60y+
- Diabetes
- Hypertension
- Coronary artery disease
- Previous MI
- Structural heart disease (valve/congenital defects)
atrial fibrillation causes/ risk factors
cardiac
- Increased atrial pressure, increased atrial mass, atrial fibrosis/ inflammation/ infiltration
- Hypertension
- Heart failure
- MI
- Coronary artery disease
- structural heart disease inc Valvular
- Cardiac surgery
- Cardiomyopathy
- Rheumatic heart disease
non cardiac
- Acute excess alcohol intoxication, exposure to caffeine tobacco etc
- hyperthyroidism
- chest infection
- age
- DM
atrial fibrillation symptoms
- None at all /
- Dizziness
- Palpitations
- Syncope
- Chest pain
- Heart failure
- Fatigue
atrial fibrillation ecg
- Rapid, irregular QRS,
- Absent p waves - jaggedy
- No steady isoelectric baseline
atrial fibrillation/ flutter treatment
treat precipitating cause
control ventricular rate
- beta blockers
- CCB
- digoxin
- amiodraone
- lidocaine
restore sinus rhythm
- cardioversion (electricla DC shock)- defibrillator
catheter based therapy – ablate/ destroy cells
do CHADVASC (Stroke risk) to see if anticoagulation medication needed
why is verapamil (phenylalinine CCB) more effective than amlopifine (dihydropiridine CCB)?
dont act on calcium channels at rest
which beta blocker is best for post MI arrythmias and why
propanolol
additional quality of blocking sodium channels
cardioversion is associated with what risk
so what is given alongside
risk of thromboembolism, so need to give LMW heparin
lidocaine action
blocks the inactivation gate of Na channels so prolongs inactivation meaning higher depolarization threshold and early action potentials less likely to get through
for arrythmias (vent trach)
digoxin action
Slows HR
Increases contractility
atrial fibrillation complications
Sudden death Syncope (fainting) Heart failure Chest pain Dizziness Palpitations Stroke
atrial flutter
- irregularity
- put a speed on it
- what is happening
- regularly irregular, organised but rapid
- 250-350bpm
- Due to re-entry circuit in RA from AV back to sinus
atrial flutter ecg
“saw tooth” ECG
Narrow tachycardia
Flutter waves
.
.
atrial flutter symptoms
Dizziness breathlessness Palpitations Syncope Chest pain Heart failure Fatigue
heart block
- brady/tachy
- what is happening
- which part of ecg is changed (what is normal)
- brady
- Conduction issue- signals not properly propogated from SAN to AVN to His-Purkinje system
- PR interval. normal is 120-200ms. heart block= greater
first degree heart block symptoms
asymptomatic
second degree mobitz type 1 symptoms
lots asymptomatic
light headed
dizzy
syncope
second degree mobitz type 2 symptoms
less likely to be asymptomatic light headed dizzy syncope chest pain SOB postural hypertension