ECG

PHYSIOLO

GY

&

LOCALISATION OF MI

LUIGI GALVANI

PLAN

1 RECALL THE GREAT WORK

OF LEGENDS

2 REVISE THE PRESENT

3 APPLY TO SAVE LIVES

..

1 HISTORY AND GROUND BREAKING ADVANCES

2 BRIEF REVIEW ON HEART AND ELECTRICITY AND MECHANICS

3 LEADS APPLICATION

4 ECG READING

5 MI PPATHOPHYSIOLOGY

6 ECG IN MI

Luigi galvani

While working in lab ,he noticed

contraction of leg muscles when

scalpel touched the nerve.

Proposed mechanism-Animal

electricity

This formed the basis of

ELECTRICITY AND CONTRACTION

OF HEART

1780- Luigi galvani

SIR HANS

CHRISTIAN

OERSTED…

PLATINUM WIRE HEATING WITH ELECTRICITY

CAUSED MOVEMENT OF COMPASS NEEDLE.

JOHANN

SCHWEIGGER

Proposed that current carrying

wire produces magnetic field.

he invented GALVANOMETER

.

CARLO MATEUCCI

EMIL DUBOIS –REYMOND

made further improvements to

the galvanometer by

increasing turns of the wire on

the coil to 24,000 ( 5 km wire )

1872 –capillary

electrometer

by GABRIAL

LIPPMANN

Open the chest

,expose the heart

and connect

electrodes and

measure the rise

/fall of potential

AUGUSTUS DESIRE

WALLER -electrogram

1ST person to attempt non

invasive measuring of heart s

electricity.

As the voltage in heart is <1

mv he tried a new technique.

He shone a light through

meniscus and projected on to

a moving photographic plate

Waller s

OBSERVATIONS

ECF surrounding heart acts as

a continuous conducting

medium between hearta and

skin.

Postulated that spread of

electricity is from apex to atria

ORIENTATION OF

HEART

EINTHOVEN

ENHANCED ELECTROMETER

DEFLECTIONS NAMING AS P,Q

,R,S,T – FOLLOWED RENE

DISCARTES, MATHEMATICIAN

AND METAPHYSICIST OF 17 TH

CENTURY WHO REPRESENTED

MATHEMATIC DEPECTIONS

WITH P ,Q, …..

Einthoven triangle

Based on various permutaitons

and combinations of placing

electrodes,einthoven finally

used 3 leads – LIMB LEADS

1,2,3

LEAD3 EQUALS DIFFERENCE

BETWEEN LEAD 2 AND 1

Nobel prize 1924

For contributions in

medicine

Wilson terminal

Wilson s central

terminal

Wilson incorporated 5 k ohms resistance to each electrode and combined 3 electrodes to form wilsons central termina

Leads-

VR-R arm paired with average of left arm and left foot

VF-left foot paired with average of right and left arms

VL-left arm paired with average of left foot and right arm

Goldberger s

augmented leads

He increased the voltages by

50 percent by increasing

resistance

V=IR

Avr,……

.

1912- James B Herrick reported clinico –pathological correlation of sudden coronary artery occlusion.

Dr .fred smith –described typical ecg patterns in 60 dogs .

He opened chests and tied each coronary arteries with strong linen , closed the chest and recorded ecg ,observed different pattern in each artery……

.

1938-AMERICAN HEART

ASSOCIATION – defined

standard positions of

precordial leads