心脏电生理及射频消融基础

What is the rate? Both atrial and ventricular if they are not the same. Is the rhythm regular or irregular? Do the P waves all look the same? Is there a P wave for every QRS and conversely a QRS for every P wave? Are all the complexes withe rhythm and any abnormalities.
• Embolic risk may be less than in fibrillation, but same recommendations apply
Electrophysiology II – Supraventricular Arrhythmias
Ventricular rate 150 bpm
Train your eyes for Rhythm:



Train your eyes for Axis:


Train your eyes for Intervals:


Train your eyes

Train your eyes for LVH:

Look at…in order

AVNRT
Atrial flutter – sawtooth or picket fence
Atrial flutter with rapid response
Arrhythmias: SA Block
P QRS T
Arrhythmias: Atrial Flutter
Steps to reading ECGs
Rate



Look at complexes in a 6-second strip and count the complexes; that will give you a rough estimate of rate Count the number of large boxes between two complexes and divide into 300 Count the number of small boxes between two complexes and divide into 1500 Estimate rate by sequence of numbers (see next slide)
• Occurs over a small reentrant circuit located near the AV node • The circuit consists of a fast and slow pathway connected by a common top and bottom pathway
Bundle branch blocks Look at the QRS morphology in V1 and V6
AVNRT


Acute treatment ATP or Verapamil Cardioversion if BP Long term Drugs, verapamil or bblocker EPS and RFA
Wolff-Parkinson-White Syndrome
• Relatively common cause of paroxysmal SVT in children and young adults • Due to an “extra” muscular bridge that connects the atrium and ventricle and allows the ventricle to be “excited” before the signal passing through the AV Node
Electrophysiology II – Supraventricular Arrhythmias
Retrograde p waves Rate of 145 bpm RP = 60 msec
AV Node Reentry Tachycardia (Short RP tachycardia)
Electrophysiology II – Supraventricular Arrhythmias
Differential Diagnosis of NCT

Short RP


Long RP


P buried in QRS

AVRT AT Slow-Slow AVNRT

AT Atypical AVNRT PJRT
Typical AVNRT AT JET
SUMMARY
15-71
Brugada Algorithm
Short RP’
AVNRT (S/F)
ART (orthodromic)
(-) p II, III, F
AVNR (F/S)
PJRT
Long RP’
(+) p II, III, F
ST
SNRT
Supraventricular Tachycardia

Obtain a 12 lead ECG. The location of the P wave will dictate the differential diagnosis If hemodynamically unstable (chest pain, heart failure, hypotension)- CARDIOVERSION If hemodynamically stable -AV NODAL AGENT Long term therapy depends on mechanism and can be conservative, pharmacologic or invasive EP study often needed for definitive characterization of mechanism and can cure most SVTs with 90% success rate

Arrhythmias
Ventricular fibrillation
• rapid, uncoordinated depolarization of ventricles
Tachycardia
• rapid heartbeat
Atrial flutter
• rapid rate of atrial depolarization
Sinus Node
SA Junction
Atrium (P wave)
Non-visible process on the EKG
AV node
“Slow zone”
IVC
Lead II
SUMMARY
Mechanisms of SVT
SP
FP
Atrial Tachycardia
AVNRT
AVRT
Electrophysiology II – Supraventricular Arrhythmias
P waves
Rate = 160 bpm
RP = 220 msec
Atrial tachycardia (Long RP tachycardia)
Electrophysiology II – Supraventricular Arrhythmias
Accessory Pathway Mediated Tachycardias (AV Reentry)
AV Node RT 95% of adults
AV RT (ORT) 95% of infants
AVNRT
AVRT (WPW)
Manolis, Ann IM, 1994
Heart Disease
Electrophysiology II – Supraventricular Arrhythmias
Atrial Flutter
“Typical isthmus dependent atrial flutter” is due to a macro reentrant circuit around the tricuspid valve • This rhythm can be stopped by pacing and cured with ablation
Train your eyes

Train your eyes for Rate:

Check the computer Check the rhythm strip Check I, II, avF Check I, II PR: check II QT: check the computer QRS: check I, V1
电生理相关资料
Cardiac vein stenosis
PTCA with 3.5 mm balloon
Final result
Modified Seldinger technique for percutaneous catheter sheath introduction
Sequence of P Wave Generation
Arrhythmias
= abnormal heart rhythms. Bradycardia = slower Tachycardia = faster (exercise!) Flutter: extremely rapid Fibrillation: