RIGHT BUNDLE BRANCH RIGHT BUNDLE BRANCH BLOCKBLOCK

Different Different presentations of presentations of RBBB in ECG RBBB in ECG illustrationsillustrations

DR. SHAZIADR. SHAZIA

Normal Ventricular Normal Ventricular ConductionConduction

Normal ConductionNormal Conduction fibers of LBB begin conductionfibers of LBB begin conduction impulse travels across impulse travels across

interventricular septum from interventricular septum from left to rightleft to right

towards + electrode creates towards + electrode creates small r wavesmall r wave

travels across ventricles travels across ventricles causing depolarization of both causing depolarization of both simultaneouslysimultaneously

LV contributes most to LV contributes most to complexcomplex

impulse travels away from + impulse travels away from + electrode creates primarily electrode creates primarily negative complexnegative complex

RBBBRBBB

RBBB in V1RBBB in V1 no change in initial no change in initial

impulse travelimpulse travel small r wavesmall r wave

impulse depolarizes LV by impulse depolarizes LV by itself since RBBBitself since RBBB

RV depolarized by impulse RV depolarized by impulse thru musclethru muscle

it now contributes to it now contributes to complex complex

travels toward + electrode travels toward + electrode creating positive creating positive deflectiondeflection

Right Bundle Branch BlockRight Bundle Branch BlockCriteriaCriteria

QRS duration QRS duration ≥≥ 110ms 110ms rSR’ pattern or notched R wave in VrSR’ pattern or notched R wave in V11

Wide and slurred S wave in I and VWide and slurred S wave in I and V66

R-R Pattern in RBBB and LBBBR-R Pattern in RBBB and LBBB

DIFFERENCE BETWEEN RBBB AND DIFFERENCE BETWEEN RBBB AND LBBBLBBB

BBB RecognitionBBB Recognition

Use V1Use V1 Find Terminal forceFind Terminal force Identify direction of terminal forceIdentify direction of terminal force

Downward Downward LBBB LBBB Upward Upward RBBB RBBB

Picture a Steering WheelPicture a Steering Wheel Right turn Right turn turn signal goes up turn signal goes up Left turn Left turn turn signal goes down turn signal goes down

BBB RecognitionBBB Recognition

Terminal Force in V1Terminal Force in V1 direction of deflection prior to J pointdirection of deflection prior to J point

J point

ECG ILLUSTERATIONSECG ILLUSTERATIONS

COMPLETE RBBBCOMPLETE RBBB

INCOMPLETE RBBB; rSR pattern with normal INCOMPLETE RBBB; rSR pattern with normal QRS durationQRS duration

INTERMITTANT RBBB WITH SINUS INTERMITTANT RBBB WITH SINUS RHYTHMRHYTHM

RBBB and LAFBRBBB and LAFB

IDENTIFY QUESTIONSIDENTIFY QUESTIONS

ANS:COMPLETE RBBBANS:COMPLETE RBBB

ANS: RBBB with left anterior fascicular blockANS: RBBB with left anterior fascicular block

ANS. INCOMPLETE RBBBANS. INCOMPLETE RBBB

ANS: INTERMITTENT RBBBANS: INTERMITTENT RBBB