Left bundle branch block

ST-segment elevation of at least 1 mm in height in two or more contiguous leads, or new or presumed new left bundle-branch block... 

Hypersensitivity or idiosyncrasy to quinidine or other cinchona derivatives manifested by thrombocytopenia, skin eruption or febrile reactions myasthenia gravis history of thrombocytopenic purpura associated with quinidine administration digitalis intoxication manifested by arrhythmias or AV conduction disorders complete heart block left bundle branch block or other severe intraventricular conduction defects exhibiting marked QRS widening or bizarre complexes complete AV block with an AV nodal or idioventricular pacemaker aberrant ectopic impulses and abnormal rhythms due to escape mechanisms history of drug-induced torsade de pointes history of long QT syndrome. 

Baldasseroni S, Opasich C, Gorini M, et al. Left bundle-branch block is associated with increased 1-year sudden and total mortality rate in 5517 outpatients with congestive heart failure a report from the Italian network on congestive heart failure. Am. Heart J. 2002 143 398-405. 

Stenestrand U, Tabriz F, Lindback J, England A, Rosenqvist M, Wallentin L. Comorbidity and myocardial dysfunction are the main explanations for the higher 1-year mortality in acute myocardial infarction with left bundle-branch block. Circulation 2004 110 1896-902. 

Xiao HB, Lee CH, Gibson DG. Effect of left bundle branch block on diastolic function in dilated cardiomyopathy. Br. Heart J. 1991 66 443-7. 

Sade LE, Kanzaki H, Severyn D, Dohi K, Gorcsan J, III. Quantification of radial mechanical dyssynchrony in patients with left bundle branch block and idiopathic dilated cardiomyopathy without conduction delay by tissue displacement imaging. Am. J. Cardiol. 2004 94 514-8. 

Nelson GS, Berger RD, Fetics BJ, et al. Left ventricular or biventricular pacing improves cardiac function at diminished energy cost in patients with dilated cardiomyopathy and left bundle-branch block, [erratum appears in Circulation 2001 Jan 23 103 (3) 476]. Circulation 2000 102 3053-9. 

In contrast, intravenous fibrinolytic therapy is harmful without acute ST-segment elevation, a true posterior MI or a presumed new left bundle-branch block. 

Antman developed a thrombosis in myocardial infarction (TIMI) risk score based on a database of 15,078 patients with STEMI or new onset of complete left bundle branch block (8), The score was validated in the TIMI 9 data set. Ten characteristics of these patients accounted for 97% of the predictive capacity of their multivariate model. These are included in the risk score (Table I). Points were given for difference parameters as listed in Table I. The risk score had a strong association with 30-day mortality. There was a greater >40-fold increase in mortality from TIMI risk score 0 to >8 at 30 days (Table I) (8), The TIMI risk score is easy to apply and can be done at the bedside. 

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

These data support an earlier study on the important predictive value of BNP (29). The BNP levels predicted the risk of death and nonfatal cardiac events across the spectrum of ACS. The BNP levels were supportive of other high risk factors age greater than 75 years Killip class two, three, or four ST-segment deviation greater than 1.0 mm new complete left bundle branch block troponin I, greater than 1.5 ng/mL (29). 

Other risk factors for complete heart block were left bundle branch block, first degree atrioventricular block, female gender, volume of alcohol, and number of septal perforators treated (27-29). 

A 31-year-old man developed generalized discomfort after injecting four doses of amfetamine and metamfetamine over 48 hours, but no chest pain or tightness or shortness of breath. Electrocardiography showed inverted T-waves and left bundle branch block. Echocardiography showed reduced anterior wall motion. 

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. 

A 75-year-old man who had had coronary bypass surgery was given an intravenous infusion of adenosine for stress testing (25). After 1 minute he developed a three-beat run of wide-complex tachycardia, followed by a 20-second run of a regular wide-complex tachycardia at a rate of 115/minute. There was left bundle branch block, and the tachycardia ended spontaneously. Adenosine infusion was continued and some ventricular extra beats with the same configuration occurred. In this case there was impaired perfusion of the left ventricle. 

Singh RB, Agrawal BV, Somani PN. Left bundle branch block a rare manifestation of digitalis intoxication. Acta Cardiol 1976 31(2) 175-9. 

In a 72-year-old woman cibenzoline was associated with left bundle branch block and heart failure (11). Excess cibenzoline accumulation was suspected, because of reduced renal function, but plasma cibenzoline concentrations were not reported. 

Paelinck BP, De Raedt H, Conraads V. Blurred vision, left bundle-branch block and cardiac failure. Acta Cardiol 2001 56(1) 39. ... 

A 35-year-old woman taking disopyramide phosphate modified-release capsules 150 mg qds was given azithromycin 500 mg initially and 250mg/day thereafter (36). In 11 days she developed malaise, light-headedness, and urinary retention. After the insertion of a urinary catheter she developed a monomorphic ventricular tachycardia with left bundle branch block. She was successfully cardioverted and the electrocardiogram... 

A 28-year-old man with severe hjrpertension and end-stage renal disease was given two intravenous doses of labetalol 20 mg 1 hour apart for malignant hypertension. The serum potassium concentration before treatment was 6.2 mmol/1, but 8 hours after labetalol it rose to 9.9 mmol/1 and he developed left bundle branch block, ventricular tachycardia, and hjrpotension. He was given intravenous calcium gluconate, sodium bicarbonate, and lidocaine and reverted to sinus rhythm. The potassium... 

Sinus bradycardia has been seen after a bolus injection of 50 mg, atrioventricular block after a dose of 800 mg given over 12 hours, and left bundle branch block after a mere subconjunctival injection of 2% hdocaine. 

Intracardiac conduction disturbances should not be considered as absolute contraindications to epidural anesthesia there were only nine cases of sinus bradycardia, easily reversed with atropine sulfate, in 66 patients (123). However, rare cases of complete heart block and complete left bundle branch block have occurred (SEDA-21, 132) (124). 

A man developed a hjq)ertensive crisis and transient left bundle branch block with QT interval prolongation after taking moxifloxacin (16). 

Conduction disturbances are common with propafenone and can result in sinus bradycardia, sinoatrial block, sinus arrest, any degree of atrioventricular block, and right or left bundle-branch block (SEDA-10,151) (SEDA-15,179). 

Intermittent left bundle branch block (Figure 3.34)... 

Figure 3.34 Patient with an advanced but intermittent left bundle branch block. A negative T wave is observed in the complexes that do not present left bundle branch block pattern. It is explained by cardiac memory phenomenon due to the disappearance of the pattern of left bundle...

Figure 3.40 (A) Acute phase of an infarction in a patient symmetrical T wave in III (mixed pattern of repolarisation with complete left bundle branch block. Note the clear abnormality) leads to the suspicion of associated...

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...

Heart diseases cardiomyopathy, valvular heart disease, pericarditis, hypertension, ECG alterations (left bundle branch block, WPW, repolarisation alterations, etc). 

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