Significance of Left Bundle Branch Block In Presence of Acute Myocardial Infarction
Acute myocardial interaction (commonly known as heart attack) is a heart condition that results from partial or total occlusion of one or coronary arteries, therefore reducing the significant continuous blood supply to cardiac muscles (Hamm et al, 2011) Ischemia to the heart muscles will cause hypoxia and finally damage and death of cells. Acute myocardial infraction causes permanent damage to an area of the heart its etiology is attributed to factors such as: thromboembolism, hypertension, ageing, diabetes mellitus, poor dietary practices, smoking obesity and family history of cardiovascular diseases
Left bundle branch block is where there is a delay or obstruction along the pathway that electrical impulses travel to the left side of the heart (Stevenson et al2012). The condition results from delayed conduction in the left ventricle which makes the left ventricle contract rather than the right ventricle. Left bundle branch block is a heart condition whose abnormality is seen in the electrocardiogram and sometimes makes it difficult for the heart to pump blood efficiently in the circulatory system. The condition id predominantly experienced on the left side of the heart at the location of the left atrium and ventricle. The condition is mainly diagnosed via an ECG.
Discussion
AMI and LBBB are very serious medical condition since they interfere with electrical impulses and also cause cardiac arrhythmias. However, these conditions are independent of each other and the question of whether or not left bundle branch block results to acute myocardial infarction depend on the LBBB history of the patient. Understanding the role of left bundle branch block in presence of can definitely assist medical professionals in analyzing cardiac conditions of patients
Electrocardiographic diagnosis of Left bundle branch block implies that patients are at a higher risk of acute myocardial infraction, congestive heart failure and death compared to patients without left bundle branch block. There is link between acute myocardial infraction and left bundle branch where LBBB can be significantly used as a tool for diagnosis of AMI.
LBBB alter ventricular activation, which has an impact on ventricular depolarization thereby affecting, QRS, ST-segment and T wave of the electrocardiogram. Therefore, in presence of acute myocardial infraction, left bundle branch will obscure the changes to conduction abnormality. Studies show that prevalence of LBBB and other conduction abnormalities become more with age. Consequently, occurrence of LBBB is linked to a variety of advanced cardiac diseases thereby making it a marker for both age and severe cardiac malfunction but not exclusively acute myocardial infarction (Friesinger, 2000).
Alterations in acute myocardial infra8ction may be hidden by the presence of left bundle branch block on the electrocardiogram thereby delaying its detection and remedy. Even though LBBB is used as an early sign of ruling out myocardial infraction, its presence is not necessarily linked to it. Patient with suspected acute myocardial infraction and left bubble branch block present an exceptional diagnostic and therapeutic challenge to medical personnel (Sgarbossa,1996) . Despite the chronicity of LBBB Neeland et al (2012) suggests that only a small number of patients with LBBB are diagnosed with myocardial infraction
Conclusion
According Thomas et al (2013) to there is no significant relationship between chronicity of left bundle branch block in acute myocar0dial infraction. Consequently, only minor cases of acute myocardial infraction occurred in presence of left bundle branch block. Looking at the data from a variety of researchers, it’s vivid that the presence of left bundle branch block in most situations can play very significant role in the diagnosis of acute myocardial infarction. However, LBBB might also undermine the diagnosis of AMI because a convectional type of ECG is not appropriate to identify the distinction between symptoms of LBBB and AMI.
Reference
Friesinger, G.C. & Smith, R. F.(2000). Old Age. Left bundle branch block and acute myocardial infarction:Vexing and lethal combination. Am Coll Cardiol. 2000;36(3):713-716
Hamm CW, Bassand JP, Agewall S, et al. (2011). “ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation: The Task Force for the management of acute coronary syndromes (ACS) in patients presenting without persistent ST-segment elevation of the European Society of Cardiology (ESC)”. Eur. Heart J. 32 (23): 2999–3054
Neeland, I. J.(2012). Evolving Considerations in the Management of Patients With Left Bundle Branch Block and Suspected Myocardial Infarction. J Am Coll Cardiol. 2012;60(2):96-105
Sgarbossa, E. B. et al (1996) Electrocardiographic Diagnosis of Evolving Acute Myocardial Infarction in the Presence of Left Bundle-Branch Block. N Engl J Med 1996; 334:481-48
Stevenson WG, Hernaddez AF, Carson PE, et al(2012) Indications for cardiac resynchronization therapy: 2011 update from the Heart Failure Society of America guideline committee. J Card Fail 2012; 18:94-106
Thomas K. et al(2013). Left bundle brach block and suspect myocardial infarction: does chronicity of th branch block matter?European Journal of acut cardipovascular care 5(2) 670-689
