Bundle Branch Block LBBB

Left bundle branch block (LBBB) is characteristic of poisoning and is defined by Zimetbaum et al. (2004) as QRS > 0.12 s with delayed intrinsicoid deflection in the Vi, V5, and Vs leads greater than 0.05 s. The risk of arrhythmia is greatest when QRS is >0.11 s. Right bundle branch block (RBBB) greater than 0.12 s is a fairly good predictor of arrhythmic death. 

The FTT meta-analysis confirmed that it is only patients exhibiting ST segment elevation or a left bundle branch block (LBBB) on the ECG when they present with symptoms of AMI who consistently benefit... 

The thresholds of right and left ventricular pacing leads can be difficult to assess in ICDs that do not have separate programmability for each output. This is because the morphology change of the QRS complex on a single surface ECG rhythm strip can be very subtle when capture is lost in a ventricular chamber. Also, since many of the patients for which a CRT device has been implanted have a native left bundle branch block (LBBB) pattern on their surface ECG, the RV capture and native QRS complexes can look remarkably similar. 

Left Bundle Branch Block (LBBB) and Chest Pain. 157... 

Refers to a block in the electrical impulse down one of the bundle branches, knovm either as a left or right Bundle Branch Block (LBBB/RBBB). The principle characteristic of a Bundle Branch Block is a widened QRS complex. This occurs because the impulse cannot travel down the fast conduction pathway due to the blockage (Fig. 7.1). The impulse takes an alternative route through the myocardium resulting in delayed ventricular depolarisation and the characteristic widened QRS complex (Fig. 7.2). A normal QRS complex has a width of 0.06-0.10 s (1.5-2.5 small... 

Abbreviations DM, diabetes mellitus HR, heart rate HTN, hypertension LBBB, left bundle branch block SBP, systolic blood pressure STEMl, ST-segment elevation myocardial infarction. ... 

Figure 3.41 Symmetric negative T wave (see leads I and V5) in a patient with hypertension and intermittent complete left bundle branch block, who presents symmetric T wave when the LBBB disappears after a...

Posterior/inferior (leads II, III, AVF) Summarize Q/ST itmes for use in PREDICT point computation Q/ST Score Add scores to got Q/ST score (enter 0-15) — Circle any bundle branch block (BBB) for use in PREDICT point Computation Right BBB MN code 7.2.1 RBBB Left BBB MN code 7.1.1 LBBB Intraventricular MN code 7.4 IVB PREDICT point computation 1 ... 

AF atrial fibrillation CHF congestive heart failure ICD implantable cardioverter defibrillator LBBB left bundle branch block LVEDD left ventricular end diastolic dimension LVEF left ventricular ejection fraction 6MHWD 6-minute hall walk distance NSR normal sinus rhythm QoL quality of life TDI tissue Doppler imaging. 

An incomplete Bundle Branch Block has the same appearance as either a LBBB or a RBBB with the exception of the QRS duration. The QRS width does not fit the requirement for a true Bundle Branch Block but the other features are present. 

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