Cardio

9/24/99

 

• Ischemia—inverted T wave, the ventricles are having trouble repolarizing—having trouble getting blood to the ventricles
• Hypothyroidism can lead to inverted T wave
• Ischemia can lead to inverted to –PVC, right atrial enlargement

 

Ventricular Ectopic Rhythms

• Sympathetics innervate the ventricles—would want to adjust the thoracic
• Multi-focal PVC's are life threatening
• Ventricular bigeminy—pairs of things happening (SA node fire then a PVC)

 

Leads

• A view
• A perspective where an electrode is and watches the signal coming towards and going away
• Have a 12 lead system
• Electrodes do not equal a lead
• Only have 10 wires to a pt, and receive 12 views
• By changing the polarity of the wires, get the different views
• Get 6 which are standard leads—limb leads
• 4 electrodes on the limbs
• get 6 views

I.  –aVR –from R to L in a horizontal plane across the heart

II.  –Standard rhythm strip—aVF –from R to L on a down diagonal across the heart—follows the way a normal heart is to depolarize

III.               –aVL –from L to R on a down diagonal with LA (-)

§         R=right

§         L=left

§         F=foot

§         Paste on shoulders and umbilicus area

§         In all of these leads, QRS should be positive (above the line)

§         Positive means that the signal is moving toward the leads

§         0-90° is normal for the QRS axis

§         Ventricular hypertrophy ®  the current of depolarization is heading towards the ®

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