Syncope in Elderly
- Syncope = decrease in brain perfusion leading to loss of postural tone
- Neurally mediated (neurocardiogenic syncope, carotid hypersensitivity)
- Orthostasis (PD c/b ANS dysfcn, multi-system atrophy, drugs, DM)
- Arrhythmia (Afib, AV block, SSS, VT)
- CV/structural (MI, AS, PE)
Posted 11/07/16 09:14:15 AM by Matthew Cummings
Characteristics of Complete Heart Block
- More P waves than QRS complexes exist and no relationship (AV dissociation) exists between them.
- Escape rhythm may arise within the AV node (resulting in a narrow QRS complex), or lower in the conduction system (producing a wide QRS complex).
- The ventricular rate varies from 30–40 beats/min.
- Atrial rate is faster than the ventricular rate (60–100 beats/min) presumably in response to the hemodynamic consequences of the block (relative hypotension).
Posted 11/07/16 09:21:07 AM by Matthew Cummings
Accelerated junctional rhythm
- Rate of an AV junctional pacemaker exceeds >> rate of sinus node due to increased automaticity in AV node + decreased automaticity in sinus node.
- Narrow complex (QRS < 120ms), ventricular rate ~60 – 100 bpm
- Retrograde P waves may be present (inverted in the inferior leads, upright in aVR + V1).
- AV dissociation may be present with the ventricular rate usually greater than the atrial rate.
- Junctional Escape Rhythm: 40-60 bpm
- Accelerated Junctional Rhythm: 60-100 bpm
- Junctional Tachycardia: > 100 bpm
- Causes of junctional rhythms
- Digoxin toxicity
- Myocardial ischaemia
- Cardiac surgery (classically mitral valve)
Posted 11/07/16 09:28:09 AM by Matthew Cummings
When to consider PPM?
- Symptomatic bradycardia that cannot be reversed (meds, electrolytes, etc)
- Mobitz II or CHB even if asymptomatic (ventricular/junctional escape = unreliable = high-risk for hemodynamic collapse)
- Formal indications below
Posted 11/07/16 09:43:53 AM by Matthew Cummings
For further reading...
Posted 11/07/16 09:46:33 AM by Matthew Cummings
Created by Christopher Kelly
Know a hypochondriac? Get them the best-selling book 'AM I DYING?!: A Complete Guide to Your Symptoms, and What to Do Next'
The information on the website does not constitute official guidelines except where explicitly stated.
It is not meant to replace the advice of a health professional.