History

Fact Explanation
Palpitations In LBBB, the impulse of ventricular activation is not transmitted through the left bundle of main trunk of His fibers. So the left ventricle is activated later when compared to the right ventricle. The impulse to the left ventricle comes through the interventricular septum from the activated right ventricle. This prolonged ventricular systole is responsible for the prolonged QRS duration in ECG. [8]
Asymptomatic [1] In some patients left bundle branch block (LBBB) can be asymptomatic. [3]
History of congenital heart disease [3] Ostium primum atrial septal defect, atrio-ventricular septal defects and tricuspid atresia are recognized congenital heart diseases that are seen in association with LBBB.
History of cardiac surgery Corrective surgery for tetrology of Fallot and ventricular septal defects, septal myectomy and subvalvar aortic resection carry significant risk of LBBB. [6,7]
Dyspnea on exertion Patients complain of dyspnea on exertion and marked exercise intolerance. They may also complain of fatigue. [3]
Pre-syncope or syncope [4,5] Patients may complain of presyncope or syncope due to reduced cardiac output and bradycardia.
History of certain cardiac diseases Patients with myocarditis, cardiomyopathy, myocardial infarction, rheumatic heart disease and aortic valve endocarditis are at risk of acquired LBBB. [2]
References
  1. FRANCIA PIETRO, BALLA CRISTINA, PANENI FRANCESCO, VOLPE MASSIMO. Left bundle-branch block—pathophysiology, prognosis, and clinical management. Clin Cardiol [online] December, 30(3):110-115 [viewed 28 June 2014] Available from: doi:10.1002/clc.20034
  2. ROTMAN M., TRIEBWASSER J. H.. A clinical and follow-up study of right and left bundle branch block. Circulation [online] 1975 March, 51(3):477-484 [viewed 28 June 2014] Available from: doi:10.1161/01.CIR.51.3.477
  3. BREITHARDT G, BREITHARDT OA. Left Bundle Branch Block, an Old-New Entity J Cardiovasc Transl Res [online] 2012 Apr, 5(2):107-116 [viewed 28 June 2014] Available from: doi:10.1007/s12265-011-9344-5
  4. AZOCAR DAMIáN, RUIZ-GRANELL RICARDO, FERRERO ANGEL, MARTíNEZ–BROTONS ÁNGEL, IZQUIERDO MAITE, DOMíNGUEZ ELOY, PALAU PATRICIA, MORELL SALVADOR, GARCíA–CIVERA ROBERTO. Syncope and Bundle Branch Block. Diagnostic Yield of a Stepped Use of Electrophysiology Study and Implantable Loop Recorders. Revista Española de Cardiología (English Edition) [online] 2011 March, 64(3):213-219 [viewed 28 June 2014] Available from: doi:10.1016/j.rec.2010.10.017
  5. BRIGNOLE M., MENOZZI C., MOYA A., GARCIA-CIVERA R., MONT L., ALVAREZ M., ERRAZQUIN F., BEIRAS J., BOTTONI N., DONATEO P.. Mechanism of Syncope in Patients With Bundle Branch Block and Negative Electrophysiological Test. Circulation [online] 2001 October, 104(17):2045-2050 [viewed 28 June 2014] Available from: doi:10.1161/​hc4201.097837
  6. GODMAN M. J., ROBERTS N. K., IZUKAWA T.. Late Postoperative Conduction Disturbances After Repair of Ventricular Septal Defect and Tetralogy of Fallot: Analysis by His Bundle Recordings. Circulation [online] 1974 February, 49(2):214-221 [viewed 28 June 2014] Available from: doi:10.1161/01.CIR.49.2.214
  7. GABRIEL HARALD M, HEGER MARIA, INNERHOFER PETRA, ZEHETGRUBER MANFRED, MUNDIGLER GERALD, WIMMER MARIA, MAURER GERALD, BAUMGARTNER HELMUT. Long-term outcome of patients with ventricular septal defect considered not to require surgical closure during childhood. Journal of the American College of Cardiology [online] 2002 March, 39(6):1066-1071 [viewed 28 June 2014] Available from: doi:10.1016/S0735-1097(02)01706-0
  8. VASSALLO J. A., CASSIDY D. M., MARCHLINSKI F. E., BUXTON A. E., WAXMAN H. L., DOHERTY J. U., JOSEPHSON M. E.. Endocardial activation of left bundle branch block. Circulation [online] 1984 May, 69(5):914-923 [viewed 30 June 2014] Available from: doi:10.1161/01.CIR.69.5.914

Examination

Fact Explanation
Bradycardia Bradycardia is seen in some patients with LBBB. [3]
Abnormal first heart sound First heart sound can be either absent or diminished. [1]
Reversed splitting of the second heart sound In left bundle branch block the second heart sound splits during expiration and it is heard as a single sound during inspiration. [2]
References
  1. GRINES C. L., BASHORE T. M., BOUDOULAS H., OLSON S., SHAFER P., WOOLEY C. F.. Functional abnormalities in isolated left bundle branch block. The effect of interventricular asynchrony. Circulation [online] 1989 April, 79(4):845-853 [viewed 28 June 2014] Available from: doi:10.1161/01.CIR.79.4.845
  2. ORAVETZ J., WISSNER S., ARGANO B., LUISADA A. A.. Dynamic Analysis of Heart Sounds in Right and Left Bundle-Branch Blocks. Circulation [online] 1967 August, 36(2):275-283 [viewed 28 June 2014] Available from: doi:10.1161/01.CIR.36.2.275
  3. ANDERSON NATHAN S., RAMIREZ ALEXIES, SLIM AHMAD, MALIK JAMIL. Exercise Induced Left Bundle Branch Block Treated with Cardiac Rehabilitation: A Case Report and a Review of the Literature. Case Reports in Vascular Medicine [online] 2014 December, 2014:1-4 [viewed 28 June 2014] Available from: doi:10.1155/2014/204805

Differential Diagnoses

Fact Explanation
Right bundle branch block Right bundle branch can be diagnosed with ECG. The S wave is wide in the left lateral leads. QRS duration is more than 120 milliseconds in right bundle branch block as for the LBBB. [4,5]
Wolf-Parkinson White syndrome In Wolf-Parkinson White syndrome, there is an aberrant conduction pathway connecting the right atrium and the ventricle. Presence of a delta wave (a positive deflection just before the R wave) is characteristic. [6]
Myocardial infarction A newly diagnosed LBBB indicates a possibility of a myocardial infarction. [1,2]
Lenegre disease Lenegre disease is an inherited disease of the heart which results in cardiac conduction abnormalities. [3]
References
  1. FRANCIA PIETRO, BALLA CRISTINA, PANENI FRANCESCO, VOLPE MASSIMO. Left bundle-branch block—pathophysiology, prognosis, and clinical management. Clin Cardiol [online] December, 30(3):110-115 [viewed 28 June 2014] Available from: doi:10.1002/clc.20034
  2. NEELAND IAN J., KONTOS MICHAEL C., DE LEMOS JAMES A.. Evolving Considerations in the Management of Patients With Left Bundle Branch Block and Suspected Myocardial Infarction. Journal of the American College of Cardiology [online] 2012 July, 60(2):96-105 [viewed 28 June 2014] Available from: doi:10.1016/j.jacc.2012.02.054
  3. SMITS J, VELDKAMP M, WILDE A. Mechanisms of inherited cardiac conduction disease. Europace [online] 2005 March, 7(2):122-137 [viewed 28 June 2014] Available from: doi:10.1016/j.eupc.2004.11.004
  4. CORRADO D., BASSO C., BUJA G., NAVA A., ROSSI L., THIENE G.. Right Bundle Branch Block, Right Precordial ST-Segment Elevation, and Sudden Death in Young People. Circulation [online] 2001 February, 103(5):710-717 [viewed 28 June 2014] Available from: doi:10.1161/​01.CIR.103.5.710
  5. BUSSINK B. E., HOLST A. G., JESPERSEN L., DECKERS J. W., JENSEN G. B., PRESCOTT E.. Right bundle branch block: prevalence, risk factors, and outcome in the general population: results from the Copenhagen City Heart Study. European Heart Journal [online] December, 34(2):138-146 [viewed 28 June 2014] Available from: doi:10.1093/eurheartj/ehs291
  6. KULIG J., KOPLAN B. A.. Wolff-Parkinson-White Syndrome and Accessory Pathways. Circulation [online] December, 122(15):e480-e483 [viewed 28 June 2014] Available from: doi:10.1161/​CIRCULATIONAHA.109.929372

Investigations - for Diagnosis

Fact Explanation
ECG The QRS duration of 120 milliseconds or more. This is one of the most important diagnostic criteria. R wave in leads I, aVL, V5, and V6 are broad and notched which is a classic finding in ECG. In leads I, V5, and V6 the Q wave is absent. QRS complex and the T waves are directed opposite to each other. rS pattern can be detected in V1 to V2 leads. [1,2,3]
Echocardiogram [1] Abnormal posterior motion of the interventricular septum is seen in LBBB. [3]
Holter monitoring [1] Holter monitoring is helpful in detecting transient LBBB.
Chest X-ray Cardiothoracic ratio is increased in chest X-ray. [3]
Exercise ECG [1] Detects exercise induced LBBB. [4]
References
  1. RAUTAHARJU P. M., SURAWICZ B., GETTES L. S.. AHA/ACCF/HRS Recommendations for the Standardization and Interpretation of the Electrocardiogram: Part IV: The ST Segment, T and U Waves, and the QT Interval: A Scientific Statement From the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society: Endorsed by the International Society for Computerized Electrocardiology. Circulation [online] 2009 March, 119(10):e241-e250 [viewed 28 June 2014] Available from: doi:10.1161/​CIRCULATIONAHA.108.191096
  2. FRANCIA PIETRO, BALLA CRISTINA, PANENI FRANCESCO, VOLPE MASSIMO. Left bundle-branch block—pathophysiology, prognosis, and clinical management. Clin Cardiol [online] December, 30(3):110-115 [viewed 28 June 2014] Available from: doi:10.1002/clc.20034
  3. BREITHARDT G, BREITHARDT OA. Left Bundle Branch Block, an Old-New Entity J Cardiovasc Transl Res [online] 2012 Apr, 5(2):107-116 [viewed 28 June 2014] Available from: doi:10.1007/s12265-011-9344-5
  4. SAID SA, BULTJE-PETERS M, NIJHUIS RL. Exercise-induced left bundle branch block: an infrequent phenomenon: Report of two cases World J Cardiol [online] 2013 Sep 26, 5(9):359-363 [viewed 28 June 2014] Available from: doi:10.4330/wjc.v5.i9.359

Management - Specific Treatments

Fact Explanation
Conservative management Asymptomatic patients may not require any treatment. [1]
Pacemaker implantation Patients who complain of presyncope or syncope are better treated with a pacemaker implantation. [3] Presence of left anterior hemiblock should also be considered as a risk factor for sudden cardiac death and definitive treatment should be prescribed. [4] Patients with symptomatic bifascicular block should also be treated with pacemaker implantation. [5]
Cardiac resynchronization therapy (CRT) Patients with symptomatic heart failure benefit from cardiac resynchronization therapy. [2]
References
  1. FRANCIA PIETRO, BALLA CRISTINA, PANENI FRANCESCO, VOLPE MASSIMO. Left bundle-branch block—pathophysiology, prognosis, and clinical management. Clin Cardiol [online] December, 30(3):110-115 [viewed 28 June 2014] Available from: doi:10.1002/clc.20034
  2. BREITHARDT G, BREITHARDT OA. Left Bundle Branch Block, an Old-New Entity J Cardiovasc Transl Res [online] 2012 Apr, 5(2):107-116 [viewed 28 June 2014] Available from: doi:10.1007/s12265-011-9344-5
  3. MADDALI MADANMOHAN. Cardiac pacing in left bundle branch/ bifascicular block patients. Ann Card Anaesth [online] 2010 December [viewed 28 June 2014] Available from: doi:10.4103/0971-9784.58828
  4. BIAGINI E, ELHENDY A, SCHINKEL AF, NELWAN S, RIZZELLO V, VAN DOMBURG RT, RAPEZZI C, ROCCHI G, SIMOONS ML, BAX JJ, POLDERMANS D. Prognostic significance of left anterior hemiblock in patients with suspected coronary artery disease. J Am Coll Cardiol [online] 2005 Sep 6, 46(5):858-63 [viewed 30 June 2014] Available from: doi:10.1016/j.jacc.2005.05.059
  5. CAPPATO R.. The case of chronic bifascicular block: still a worrying ECG finding?. Europace [online] December, 11(9):1140-1141 [viewed 30 June 2014] Available from: doi:10.1093/europace/eup245