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 within normal time limits Name the rhythm and any abnormalities.
AVRT
WPW or concealed accessory pathway acute and chronic treatment similar to AVNRT avoid b-blocker and verapamil in known WPW
Atrial Flutter
Marcoreentrant circuit in RA terminate by cardioversion with high success rate poorly controlled by medical therapy EPS + RFA
Retrograde p waves
RP = 60 msec
Ectopic Atrial Tachycardia Long RP tachycardia
Uncommon cause of paroxysmal SVT in the young adult < 5% Occurs in a small region of either the right or left atrium
P waves
RP = 220 msec
Atrial tachycardia
Long RP tachycardia
Electrophysiology II – Supraventricular Arrhythmias
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
AV Node Reentry Tachycardia
Rate of 145 bpm
Short RP tachycardia
Electrophysiology II – Supraventricular Arrhythmias
PJRT
ST
Nodal Reentrant Tachycardia AV Node Reentry or AVNRT
Most common cause of paroxysmal SVT in the young adult 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
Atrial Tachycardia
AVNRT
AVRT
FP
SP
Differential Diagnosis of NCT
Short RP AVRT AT Slow-Slow AVNRT
Long RP AT Atypical AVNRT PJRT
P buried in QRS Typical AVNRT AT JET
SUMMARY
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
Train your eyes
Train your eyes for Rate: Check the computer Train your eyes for Rhythm: Check the rhythm strip Check I II avF Train your eyes for Axis: Check I II Train your eyes for Intervals: PR: check II QT: check the computer QRS: check I V1
AVNRT
Manolis Ann IM 1994
AVRT WPW
Heart Disease
Arrhythmias = abnormal heart rhythms. Bradycardia = slower Tachycardia = faster exercise Flutter: extremely rapid Fibrillation: Contractions of different groups of myocardial cells at different times. Ventricular fibrillation is life-threatening.
Electrophysiology II – Supraventricular Arrhythmias
Atrial Flutter
Ventricular rate 150 bpm
Saw tooth p waves
Atrial Flutter
Electrophysiology II – Supraventricular Arrhythmias
15-71
Brugada Algorithm
Supraventricular Tachycardia
Short RP’
Long RP’
AVNRT (S/F)
ART (orthodromic)
(-) p II, III, F
(+) p II, III, F
Variable p axis
AVNR (F/S)
Electrophysiology II – Supraventricular Arrhythmias
Accessory Pathway Mediated Tachycardias AV Reentry
AV RT (ORT)
AV Node RT
95% of infants
95% of adults
Excellent handout training template
心脏电生理及射频消融基础
Cardiac vein stenosis
PTCA with 3.5 mm balloon
Final result
Modified Seldinger technique for percutaneous catheter sheath introduction
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
Arrhythmias
Ventricular fibrillation rapid uncoordinated depolarization of ventricles
Tachycardia rapid heartbeat
Atrial flutter rapid rate of atrial depolarization
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 b-blocker EPS and RFA
Train your eyes
Train your eyes for LVH: Look at…in order avL V3 V1 V5V6 Check your cheat sheet Read the computer Train your eyes for MI: Look at all T waves Look at all ST segments Check for Q waves Check for R waves in V1-2
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
Sequence of P Wave Generation
Sinus Node
SA Junction
Atrium
P wave
Non-visible process on the EKG
AV node
“Slow zone”
IVC
Lead II
SUMMARY Mechanisms of SVT
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 Embolic risk may be less than in fibrillation but same recommendations apply
Electrophysiology II – Supraventricular Arrhythmias
Frequently due to an automatic mechanism making it difficult to reproduce in EP Lab
Rate = 160 bpm