ecg

1. ECG OF THE WEEK
M6 UNIT CHIEF : DR. RAJENDRAN MD
ASSISTANT PROFESSORS: DR. SENTHIL KUMAR MD
DR. T.M.PRABHU MD

2. HISTORY
• A 51 yr old male Mr Ramesh came with c/o
sudden onset of palpitation
giddiness
h/o sweating
No h/o chest pain , breathlessness
N/K/C/O DM , HTN , CAD , epilepsy , TB

3. EXAMINATION
GENERAL EXAMINATION
• Consious , oriented
• obese
• Afebrile
• No pallor/ cyanosis /clubbing/ pedal edema
• JVP not elevated
• VITALS
• Bp – 100 / 70 mm Hg
• PR – 180/ min regular Tachycardia

4. SYSTEMIC EXAMINATION
• CVS – S1 S2 heard
no murmur
• RS – NVBS heard
no added sound
• P/A – soft , no organomegaly
• CNS - NFND

6. ECG

9. FINDINGS
• HR – 180/ min
• Narrow QRS complex
• Regular tachycardia with retrograde P waves
• Short RP interval
• A case of TYPICAL AVNRT

11. AVNRT
• Most common type of Rentrant tachycardia
• Most common in females
• 3 or 4th decade
• This reentrant rhythm requires functional
dissociation of AV node into two pathways
with Anterograde conduction down the slow
pathway and retrograde conduction up the
fast pathway

12. TYPES
• Typical – slow- fast pathway (alpha) 95%
• Atypical – fast – slow pathay 5%
• Slow slow pathway 2%
• Slow accessory pathway rare

13. • Slow pathway has short refractory period and
slow conduction
• Fast pathway has fast conduction and long
refractory period
• Rentry occurs when 2 pathways are with
different conduction properties and there
should be unidirectional block

14. TYPICAL AVNRT
• Short RP interval
• Sometimes atrial activation can occur at the
terminal portion of QRS to create PSEUDO r’
(v1) or pseudo-s’ (lead 2)

15. ATYPICAL AVNRT
• Less common
• Anterograde conduction proceeds down the
fast pathway with retrograde conduction up
the slow AV pathway, leading to long RP
interval
• ECG : Retograde p wave is well inscribed after
QRS complex in the second half of RR interval

16. MECHANISM OF PSVT
• BASED ON RP INTERVAL
Short RP interval Tachycardia
RP interval < 50% of RR interval
1. AVNRT typical
2. o-AVRT
3. Junctional tachycardia
4. Ectopic atrial tachycardia with 1st degree
block

21. • Long RP interval tachycardia
RP interval > 50 % RR interval
1. Atypical AVNRT
2. sinus tachycardia or ectopic atrial
tachycardia with normal PR Interval
3. EAT
4. O-AVRT with slow conduction via bypass
tract

22. CLINICAL FEATURES
• Occurs in patients with no structral heart
disease
• Palpitation , nervousness , syncope , heart
failure or shock
• Prognosis of patient without heart disease is
good

25. TREATMENT
• Sedation , Reassurance , vagal maneuvers
• 1. carotid sinus massage
• 2. gag reflex
• 3.Valsalva maneuvers
• 4.Coughing
• 5. immersion of face into cold water

26. DRUGS
• ADENOSINE – 6 mg intially then 12 mg followed
by 12 mg pushing with 20 ml NS flush
• VERAPAMIL – 5 -10 mg IV
• DILTIAZEM – 0.25 to 0.35 mg / kg in 2 minutes
• DIGITALIS – slow onset of action and has longer
effect
0.5 mg every 24 hrs
total dose < 1.5 mg per 24 hrs

27. • In cardiac decompensation – DC shock (50J)
• RADIOFREQENCY ABLATION : More than 95%
effective

28. • THANK YOU