Ventricular Rhythms (DM)

When do ventricular rhythms form

sinoatrial (SA) node or the AV junctional tissues fails to generate an impulse

the VENTRICLES will assume the role of pacing the heart

ventricular rhythms

Rhythms that are initiated in the area of the ventricular

What is the least efficient pacemaker of the heart

Ventricules

How are atria depolarized in ventricular

Retrograde depolarizaation

What are common charateristics of ventricular rhythms

QRS are wide (> 0.12 sec) and bizarree

P waves are absent as they get hidden or buried in QRS

Premature Ventricular Complexes (PVC)

Single ectopic (out-of-place) complex that occurs earlier then the next expected complex

PVCs

What are the suggestive indicators of PVCs

Compensatory Pause

Wide, Bizarre, Premature QRS Complex

Where do PVCs come from

irritable site in the ventricles

PVCs are usually followed by

Compensatory Pause

Interpolated Bear

A PVC that fall between two sinus beats without interfering with the rhythm

What is the shape of the PVC base don

Site of Origin

Ventricular Bigeminey

PVC every other bear

Ventricular trigeminey

PVC every 3rd beat

Ventricular quadrigemeny

PVC every 4th beat

Couplet or Repetiteve PVC

Two PVC occuring together without complex in between

Runs of Ventricular Tachycardia

Three or more PVCs in a row

Characteristics of PVCs (5-Step)

1. Rate dependent on underlying rhythm and number of PVCs

2. Rhythm is occasionally irregular, regular if interpolated PVC

3. No P wave with PVC | P waves of underlying rhythms

4. PR interval not seen with PVC

5. QRS of PVC is wide and bizarre (> 0.12 sec)

Unifocal PVCs

Multifocal PVCs

Salvos

Runs of Ventricular Tachycardia (3+ PVCs)

PVCs often indicate

Myocardial irritability

Ventricular Bigemey + Couplet PVC

Ventricular Bigemny

Ventricula Trigeminy

Salvo / Run of V-tach

Salvo / Run of VT

Salvo / Run of VT

Idioventricular Rhythms / ventricular escape rhythms

Means SA node and AV node have failed

Rate usually less than 40 BPM, and cardiac output is usually compromised

Agonal Rhythm

idioventricular rhythm falls below 20 BPM

When is agonal rhythm usually seen

either resuscitation is unsuccessful or after successful defibrillation

Causes of Idioventricular Rhythms

extensive myocardial damage

secondary to acute myocardial infarction

failure of higher pacemakers

Idioventricular Rhythm

Characterisitics of Idioventricular Rhythms

1. Rate is 20-40 bpm

2. Atrial rhythm is not distinguishable | Ventricular is regular

3. No P waves

4. No PR interval

5. QRS are biazzare and wide ( > 0.12 sec)

Accelerated Idioventricular Rhythm

occur when the rate of the ectopic pacemaker exceeds 40 BPM

Accelarated Idioventricular Rhythm

What separates Accelarted Idioventricular from V-tach

Idio is < 100 bpm so it is not a tach

Ventricular Tachycardia Rhythms

three or more PVCs arise in sequence at a rate greater than 100 BPM

Sustained Ventricular Tachycardia

Lasts longer than 30 secs

Nonsustained Ventricular Tachycardia

Last less than 30 sec (Salvo / Run of V tach)

Ventricular Tachycardia

How do we subdivde V-tach

Pulseless or Pulse

Pulseless V-tach should always recieve

Immediate defib

Treatment of Unstable V-tach with Pulse

Immediate cardioversion

Treatment of Stable V-tach with Pulse

Drug intervention

Causes of V-tach

Myocardial ischemia,

hypoxia,

electrolyte imbalances

, increased anxiety or physical exertion,

underlying heart disease

Characterisitics of V-tach

1. Rate = 100-250 bpm

2. Atrial rhythm is not seen | Ventricular is regular

3. P wave may be seen but usually absent

4. No PR

   1. QRS is uniform, bizaare, and wide

Torsades De Pointes

Morphology of QRS complexes shows variations in width and shape

Resembles a turning about or twisting motion along base line

Causes of Torsades De Pointes

Hypokalemia

Hypomagnesemia

TCA OD

Use of Antidysryhtmia

Combination

Torsades De Pointes

Treatment of Choice for Torsades De Pointes

Magnesium

most frequent initial rhythm occurrence in sudden cardiac arrest

Ventricular Fibrillation

Ventricular Fibrillation

a result of multiple weak ectopic foci in the ventricles

appear to quiver rather than depolarize normally

What is not present with V-fib

Atrial contraction

Ventricular contractions

Palpable Pusle

How is waveforms for V-fib

disorganized, rapid, irregular waves whose morphology varies vastly

Fine ventricular fibrillation

Ventricular fibrillation waves less than 3 mm of amplitude

Coarse ventricular fibrillation

Ventricular fibrillation waves with amplitudes greater than 3 mm

What is critical to determine if monitor shows V-fob

artifact, or loose leads

Causes of V-fib

Acute MI

Ischemia

Drug Tox or OD

Hypoxia

Characteristics of V-fib

1. Rate is not discerned

2. Rhythm is rapid and unorganized

3. No P

4. No PR

5. No QRS

Fine V-fib

Coarse V-fib

Ventricular Asystole / Standstill / Asystole

The absence of all ventricular activity

How does asystole look

flat line, and is the absence of all cardiac electrical activity

How is asystole determined from fine V-fib

Check two different leads

Causes of Ventricular Asystole

Massive MI

Cardiac trauma

Ventricular Aneurysm

Complete Heart Block

Characteristics of Ventricular Asystole

1. No rate

2. No rhythm

3. No P

4. No PR

5. No QRS

Asystole

Pulseless Electrical Activity

absence of a palpable pulse and myocardial muscle activity with presence of organized electrical activity on the cardiac monitor

What rhythm was formerly electromechanical dissociation, or EMD

Pulseless Electrical Activity

Causes PEA

Profound hypovolemia

Massive myocardial damage

Ventricular Rupture

PE

Acidosis

Cardiac Tamponade

Hypo/Hyperthermia

Drug OD

Hypo/Hyperkalemia

Tension Pneumo

What has shown assocaited to PVCs

Caffeine Intake

Stress

Giving what may cause PVCs to dissapear

O2

What is important to determine when assessing many ventricular rhythms

Perfusion status

What causes CO to compromise in V-tach

rapid heart rate, ventricles do not have time to empty and refill

The presence of fine V-fib indicates

The rhythm has been present for extended perioid