Bipolar electrocardiography

María Carolina Rodríguez Burgos 

Diego Alejandro Morales Gil
Angie Tatiana Sandoval Patiño 

GLOSSARY

PHYSIOLOGY

ELECTROCARDIOGRAM (ECG) WITH THREE LEAD

The ecg apart from taking the electrical activity of the heart with each of its waves, we can also observe the different derivations that is like a shot of the same electrical record but seen from another angle, there are different types of derivations: bipolar, unipolar and precordial.

The bipolar derivatives which were proposed by Einthoven, which said that the human body as conductor of electricity and the heart as a generator of current, could be made a triangle in an imaginary way, between members where the electric forces generated by the heart.

Since the heart is not located in the center of the chest if not to the left side and the legs as the most distal part of the body, in such a way the triangle is constructed from arm to right to left arm, ending in the left leg.

In the right arm is the negative part of the derivations, meaning closer to the heart and the left leg become positive poles.

This registers the potential differential between the electrodes connected to the body in different specific parts.

There are three types of bipolar leads:

D1: potential difference between the right arm and left arm

D2: potential difference between right arm and left leg

D3: potential difference between left arm and left leg

limb and einthoven triangle leads

These derivatives are important to determine the heart rate, the position 

of the heart, measurements of the waves, spaces and segments, diagnosis 

and differential of arrhythmias and heart rate.Eithoven proposed 

a law that postulates D2 = D1 + D3

To find these dereivations we can use the unipolar derivations which are 

AVR (amplification-vector-right) AVL (amplification-vector-left) AVF 

(amplification-vector-feet)

D1 = VL - VR

D2 = VF - VR

D3 = VF - VL

In the EKG, it can be observed how



Each of the derivations represents a part of the heart in such a way that
the high lateral branches I and aVL obtain registration of the high 
lateral wall and the lower leads II, III and aVF of the inferior wall.

Through the derivation D1 together with aVF, diseases can be determined 
by making an observation in the form of the P wave if it is negative,positive, 
flat, wide and its voltage. Similarly, you can also visualize the Q wave 
where its value should

 be less than 30ms, with a voltage of 0.1 mV 

and the T wave in D1 and D3 are normally positive.

·         Diseases that can be found in bipolar leads:

·         • Right and left atrial hypertrophy: displayed in D1

·         • Binaural hypertrophy: it is visualized in D2

·         • branch locks

·         • ventricular hypertrophy: visualized in D2 and D3

·         • patterns of overload of the right ventricle: it is visualized 

         in D2 and D3

·         • left ventricular overload patterns: displayed in D1

·         acute infarctions: it is visualized in D1



DESIGN



Our design is composed of LF353N, this will be connected to our 

patient and take the signals. We also have an AD620 that is an

 instrumentation amplifier where we can observe the signals 

and finally we have a band pass filter and a notch that 

will allow us to see the signals without noise.











CONCLUSION


-         
The bipolar ECG is a good technic to evaluate de
electrical conduction in the heart, in where I could found 

      anomalities and give an objective diagnostic and a possible 

     treatment.

-         
The bipolar ECG allow us see and analize different
leads of our heart, this generates different 

      alternatives to see the sides of the heart and compare

      with another leads, to get exactly information for the health
professional.

-         
When you will make and electrical circuit from ecg its
important has different points, the first one is make a protection 

     to the patient, this one isolating the ground of the circuit and the 

      ground of your patient, this for protect against the current of the 

      feeding source. Then you must have and instrumentation stage with 

     an amplification stage in each output, finally you must have a 

      filtering stage to guarantee a good signal, its necessary two kind 

      o filters, pass band filter and notch filter, the pass band filter is
recommended from 0.05Hz until 40Hz, because its necessary take 

      the ultra low frecuencys and pass band until 40Hz, if you make 

      until 40Hz you guarantee that your filter don’t takes the high 

      frecuencys. Finally the notch filter is for clean your signal,

      this filter is from 60 Hz, cause this filter clean your
signal from the noise that provides de feeding source.









BIBLIOGRAPHY






uribe arango, w., duque ramírez, m., & medina durango, e. 

electrocardiography and arrhythmias. (2015) retrieved from: 

 http://www.siacardio.com/wp-content/uploads/2015/01/libro-ekg-y-arritmias-wu.pdf







lamb,p . ecg del corazón (ecg) que muestra los principales intervalos. 

retrieved from: 

 https://es.123rf.com/photo_33249896_ecg-del-coraz%c3%b3n-ecg-que-muestra-los-principales-intervalos-.html