ecg: interpreting asmi

PROF DR.MAGESHKUMAR’S UNITDR.S.GEETHALAKSHMI

35 Yr old MR. JAYAKUMAR Came with

• c/o retrosternal compressing chest pain• 2 hrs duration , Radiating to left arm• Associated diaphoresis & palpitations +nt• Smoker 15 yrs• Alcoholic 10 yrs• Not a k/c/o SHT / DM / CAD pt• Examn fairly normal• Vitals stable with a BP of 140 / 90 mm Hg

I

II

III

SHOWS

• RATE 100/min• RHYTHM normal sinus rhythm• P WAVE present with normal morphology• PR INTERVAL 0.16 secs• QRS DURATION normal• QT INTERVAL 0.32 secs• ST SEGMENT ELEVATION V1 – V4

DIAGNOSIS• ANTERIOR WALL MI

what more from what more from ecg ?ecg ?

• Localize CULPRIT CORONARY VESSELTo assess the size of ischemic area To be prepared for EXPECTED COMPLICATIONS• PROGNOSIS – ST segment score(> 15 )• Grading of ischaemia I – tall peaked symmetric R waves ii – ST elevation iii – distortion of terminal QRS

CORONARY VASCULAR ANATOMY

Sites of occlusionProximal l a d

Septal

Diagonal

Distal l a d

ECG CHANGES LOOK AT

PROXIMAL L A D

MID L A D

DISTAL L A D

V 1-4 ST ST ST

II , III , AVF ST ST (III esp.)

ST isoelectric or

AVR ,

ST ST ST

V 5 , 6 ST

AVL ST

CONDUCTION DEFECTS

RBBBLAFB

PROXIMAL L A D OCCLUSION

PROXIMAL L A D

ST ELEVATION AVR

ST DEPRESSION IN INFERIOR LEADS , V5,6

DISTAL L A D OCCLUSION

DISTAL L A D

ST DEPRESSION AVR

ST ISOELECTRIC OR ELEVATED IN INFERIOR LEADS

PROXIMAL TO SEPTAL BR.

PROXIMAL TO SEPTAL BR.

ST ELEVATED IN INFERIOR LEADS (ESP III) & AVR

ST DEPRESSED IN AVL

COMPLICATIONS

Involvement of the distal AV conduction right bundle branch block (RBBB) Left fascicular block, Heart failure and Ventricular tachycardia and fibrillation <subacute phase>

To summarize……..

A SIMPLE CARRY HOME MESSAGE ASMI ST elevation in V 1-4 reciprocal ST depression in ii ,iii , aVF

Present absent DISTAL L A D

ST elevation in V1 , a VR

Present absent ST elevation avr > V1

+ RBBB , LAFB PROXIMAL MID L A D LT MAIN BR.

DISTAL TO SEPTAL BR.

DISTAL TO SEPTAL